Blood bank ASCP MLT medialab exams

Once Fresh Frozen Plasma (FFP) has been thawed, it should be stored at what temperature? - 1 - 6 ºC - 30 - 37 ºC - 20 - 24º C - 45 - 56º C

- 1 - 6 ºC Thawed FFP is stored at 1 - 6oC and should be transfused within 24 hours of thawing. FFP is thawed in a 30 - 37o C water bath prior to administration but is not stored at this temperature. Platelets are stored at 20 - 24º C. Currently, no blood components are stored at 45 - 56º C.

Whole blood or red blood cell units will be shipped from the American Red Cross to the transfusion facility. At what temperature should the units be kept during transportation? - 1-4 °C - 1-10 °C - 2-6 °C - 2-8 °C

- 1-10 °C Whole blood or red blood cell units must be maintained between 1 and 10 °C during transportation. Blood in storage should be kept between 1 and 6 °C. All other answer choices have temperature ranges that are too restrictive.

From the IgG molecule illustration, which region is the heavy chain? - A - B - C - D

- A A = Heavy chain B = Light chain C = Antigen binding site D = Variable region

Which of the following is considered a high-incidence antigen? - K (big K) - C (big C) - c (little c) - k (little k)

- k (little k) The correct answer is k (liitle k). It occurs in approximately 98.8% of white donors and almost 100% of black donors. A high-incidence antigen is one that appears in 98% or more of the population. K (big K) appears in approximately 9% of white donors and is rare in black donors. C (big C) appears in approximately 68% of white donors and 27% in black donors. c (little c) appears in approximately 80% of white donors and approximately 97% of black donors.

Frozen red cells that have been prepared with high glycerol methods (40% glycerol) can be stored up to 10 years if held at which of the following temperatures? - - 65o C or lower - - 20o C or lower - - 10o C or lower - 0o C or lower

- - 65o C or lower Frozen red cells that are prepared using the high-glycerol technique (40%) can be stored up to 10 years at - 65o degrees Celsius or lower. Freezing red blood cells at a higher temperatures, including -20, -10, or 0 degrees Celsius is not performed.

After frozen RBC's have been thawed and washed, they must be used within how many hours? - 6 - 12 - 24 - 48

- 24 Thawed and washed units of red blood cells must be used within 24 hours. Frozen red blood cells must be washed to remove the glycerol that is added to protect the cells during the freezing process. This process requires that the unit becomes an open system and therefore it has a 24 hour expiration.

Which of the following is the proper storage temperature for fresh frozen plasma (FFP)? - 37 degrees Celsius - 4 degrees Celsius - - 20 degrees Celsius - - 10 degrees Celsius

- - 20 degrees Celsius FFP must be separated from RBCs and frozen solid at less than or equal to -18 degrees Celsius within 8 hours of collection. All of the other temperatures listed are too high for FFP storage.

When collecting routine blood product donations, the venipuncture site is first cleaned with: - 70% Isopropyl alcohol - 50% Iodine - 0.7% Iodophor compound - 2% Chlorhexidine

- 0.7% Iodophor compound A 0.7% iodophor compound is used as the first disinfectant method as it removes surface debris and bacteria and can begin the initial germicidal action on resident skin bacteria. 70% isopropyl alcohol is sufficient to be used in routine venipuncture procedures, but extra germicidal action is needed for resident skin bacteria when collecting blood donations to prevent contamination. 70% isopropyl alcohol should not be used alone or as the first step when preparing a venipuncture site for blood donations. 50% Iodine is not used as an antiseptic as it commonly causes skin irritation. A 10% povidone-iodine solution is used as a secondary antiseptic for blood donation venipunctures, following 0.7% iodophor compound. 2% Chlorhexidine may be used to cleanse the skin in venipunctures for blood donors who are sensitive to the iodophor and povidone-iodine solutions. Venipuncture sites for individuals who are sensitive to iodine-based compounds should then be cleaned with 70% isopropyl alcohol. This process is not typically used as it takes longer to clean the skin and has demonstrated improved germicidal action when compared to the iodophor and povidone-iodine procedure.

The concentration of sodium chloride in an isotonic solution is: - 8.5 % - 0.85 % - 0.08 % - 85%

- 0.85 % Isotonic, or physiologic, saline is a 0.85 % solution of sodium chloride in water. This concentration provides an environment in which the fluid exchange between red blood cells and the saline is equivalent, so that red cells do not lyse or crenate. A higher concentration of saline, such as 8.5% or 85%, creates a hypertonic solution. This means that there is a greater concentration of solutes outside of the cell than inside. This imbalance will cause the fluid inside the cell to move to the extracellular space, crenating the cell. A lower concentration of saline outside the cell, such as 0.08%, creates a hypotonic solution. In a hypotonic solution, the fluid outside of the cell will move into the cell, causing the cell to lyse.

In the Kleihauer-Betke test, a maternal blood smear is treated with acid and then stained with counterstain. The fetal cells contain fetal hemoglobin, which is resistant to acid and will remain pink. Since the calculated volume of fetomaternal hemorrhage is an estimate, how many additional RhIg vials need to be added for the dose? - 1 - 1.5 - 2 - 3

- 1 After 2000 cells are counted, the percentage of fetal cells is determined, and the volume of fetal hemorrhage is calculated by the formula: number of fetal cells X maternal blood volume / number of maternal cells = volume of fetomaternal hemorrhage. Because the Kleihauer-Betke is an estimate, one vial is added to the calculated answer.

What is the acceptable temperature range for maintaining red blood cell components during transport? - 1 - 6ºC - 1 - 10ºC - 10 - 15ºC - 20 - 24ºC

- 1 - 10ºC Red blood cell components must be maintained between 1 - 10°C during shipping. Red blood cell components (with the exception of frozen RBC units) are stored refrigerated between 1 - 6ºC. Platelets must be transported in a temperature range between 20 - 24ºC or as closely as possible. The temperature range of 10 - 15ºC is not approved for storage or transport of blood components.

At many hospitals, patients with sickle cell disease are given phenotypically matched units of blood. This policy is often used to help prevent alloimmunization to common RBC antigens in patients who are regularly transfused. A patient who regularly comes to your hospital demonstrates the following phenotype on her RBCs: C antigen positive; E antigen-negative; K antigen positive. The patient's doctor requests a single unit of crossmatched packed RBCs. Based on the antigen prevalence indicated below, how many units of ABO compatible packed RBCs will you phenotype to find one to transfuse to this patient? Antigen frequencies C antigen positive: 68% E antigen positive: 22% K antigen positive: 9% - 7 units - 77 units - 4 units - 1 unit

- 1 unit Since the patient is negative for E antigen, the patient is only capable of producing anti-E. Thus, you need to provide units that are negative only for the E antigen. You do not have to provide units that are negative for the C and K antigens. STEP 1: Since 22% of donors are positive for E antigen, 78% are negative for E antigen. 78% expressed as a decimal is 0.78 STEP 2: The reciprocal of 0.78 is calculated as follows (1/0.78) = 1.3 1.3 compatible units should be antigen typed to find a single unit negative for E antigen. Rounding to the closest whole number gives you the correct answer choice of 1. An alternate method to determine the number of units to antigen type is to solve for x using a ratio. In this case the ratio would be: 78/100 = 1/x 78x = 100 x = 1.28 or approximately 1 unit

Tube-based agglutination reactions in the blood bank are graded from negative (0) to 4+. A reaction that has numerous small clumps in a cloudy, red background is: - 1+ - 2+ - 3+ - 4+

- 1+ The correct answer is 1+. A 1+ reaction has numerous small clumps and cloudy red supernatant. A 2+ has many medium-sized clumps and clear supernatant. A 3+ has several large clumps and clear supernatant. A 4+ has one solid clump, no free cells, and clear supernatant.

In blood banking, the Direct Antiglobulin Test (DAT) is used in the investigation of which of the following clinical conditions? 1. Hemolytic Disease of the Fetus and Newborn (HDFN) 2. IgA deficiency 3. Hemolytic Transfusion Reaction (HTR) 4. Zika virus infection - 1, 2, 3 - 1, 3 - 2, 4 - 2, 3, 4

- 1, 3 The DAT test is used to detect in vivo sensitization of RBCs, so it is most useful in detecting conditions in which antigen-antibody interactions occur in a patient's body. HDFN and HTR are two such conditions. Investigation of IgA deficiency would not usually include performing a DAT on the patient unless symptoms specifically warranted this test. Zika virus testing is performed on donated units, but infection with this virus would not normally include performing a DAT on the patient.

At what temperature should whole blood be stored? - < -65 C - < -18 C - 1-6 C - 20-24 C

- 1-6 C Whole blood must be stored at 1-6 C to maintain viability of the red blood cells. Red blood cells that are frozen without glycerolization, such as whole blood, will lyse. Temperatures < - 18 C and < -65 C would not produce viable red blood cells. Whole blood storage at room temperature increases the storage lesion effects caused by biochemical reactions within the unit and also increases the chance of bacterial contamination.

What is the shelf-life of whole blood collected in CPDA-1? - 21 days - 28 days - 35 days - 48 days

- 35 days Whole blood collected with CPDA-1, or citrate-phosphate-dextrose-adenine, has a storage (shelf) life of 35 days from the date of collection. Whole blood collected with CPD (citrate-phosphate-dextrose), CP2D (citrate-phosphate-dextrose-dextrose), or ACD (acid-citrate-dextrose) has a storage (shelf) life of 21 days from the date of collection.

A unit of red blood cells that was collected on 15 June 2009 and frozen with glycerol at -80° C on 20 June 2009 will expire on what date? -14 June 2010 - 15 June 2010 - 20 June 2019 - 15 June 2019

- 15 June 2019 The correct answer is June 15, 2019; 10 years from collecting date. Blood is sometimes frozen to maintain an inventory of rare units or extend the expiration date of autologous units. Currently, the FDA licenses frozen RBCs for a period of 10 years following collection date. Glycerol is the most commonly used agent and is added to RBCs within 6 days of collection. The recommended interval between removing the RBC unit from refrigeration and placing the glycerolized cells in the freezer should not exceed 4 hours. So, based on this information, the correct answer should be 10 years from the date of collection, which in our case is June 15, 2019; 10 years from collection date. When the blood is needed, it is thawed and deglycerolized and the expiration date is changed to 24 hours from the time of thawing.

How many doses of RhIG should be administered if the calculated amount of fetal whole blood volume in maternal circulation was 28 mL? - 1 dose - 2 doses - 3 doses - 4 doses

- 2 doses When calculating RhIG dosage, facilities always add one extra dose to the calculated dose for an added margin of safety. Each dose is effective in treating 30 mL fetal whole blood. Therefore, 28 mL fetal whole blood would require one dose, plus one additional dose.

An Rh negative mother has just given birth to an Rh positive baby. Her physician suspects that she has experienced a fetal-maternal hemmorhage since her rosette test was positive. Upon performing the Kleihauer-Betke stain procedure, the percentage of fetal cells is found to be 0.85%. The mother's total blood volume is 4,565 mL. What dose of Rh Immune Globulin (RhIG or RhoGam) should be administered to the mother? - 1 vial - 2 vials - 3 vials - 4 vials

- 2 vials Rh immune globulin, also known as RhIG or RhoGam, is used to help prevent an Rh negative mother from becoming sensitized to the D antigen from an Rh positive baby. To do this, vials of Rh Ig must be administered correctly. One full dose vial (300µg or equivalent) per 30 ml of D positive whole blood (15 ml D positive packed RBCs).To calculate how many vials are needed, the following formula can be employed: KB% x blood volume = volume of baby blood In this case: 0.85% (0.0085) x 4,565mL= 38.8 mL baby blood in maternal circulation 38.8mL / 30 mL per Rh Ig vial = 1.29 vials 1.29 vials can be rounded to 1 vial. In addition, an extra vial is always added. Therefore, 2 vials is the correct answer.

Rejuvenation solutions for donated red blood cell units may be used to improve what factor that is affected by storage lesion? - Hemoglobin - Potassium - 2,3 DPG - Sodium

- 2,3 DPG A rejuvenation solution may be added to red cell units to restore 2,3-DPG and ATP levels, which decrease during storage. A red blood cells age and lyse during storage, hemolysis will increase. Rejuvenation solutions are not able to prevent this increase in hemolysis. As red blood cells hemolyze during storage, they release potassium, which is typically present in the highest concentrations within the red cell. This results in an increase in plasma potassium levels. A rejuvenation solution cannot correct this. As red blood cells hemolyze during storage, the release of the cell intracellular fluid (ICF) dilutes the extracellular fluid (ECF) analytes. Levels of sodium, which is predominantly found in the extracellular fluid, are diluted, resulting in decreased plasma sodium levels. A rejuvenation solution cannot correct this.

The proper storage requirements for granulocyte concentrates is: - 1 - 6 degrees Celsius,12 hours - - 20 degrees Celsius, 48 hours - 1 - 6 degrees Celsius, 24 hours - 20 - 24 degrees Celsius, 24 hours

- 20 - 24 degrees Celsius, 24 hours Granulocytes are used as treatment for patients that are severely neutropenic (neutrophil count less than 500/µL) who have the following: Documented infection (24-48 hours) that is nonresponsive to antibiotic or antifungal treatment, myeloid hyperplasia demonstrated by bone marrow biopsy, and a chance of bone marrow recovery. Granulocytes are most often collected by apheresis to achieve a higher yield than those collected from whole blood. Storage is 20-24 degrees Celsius for up to 24 hours, but should be transfused as soon as possible. The other storage conditions above all have temperatures lower than what is optimal for granulocytes.

What is the required storage temperature for thawed cryoprecipitate? - 4 - 8 ºC. - 20 - 24 ºC. - 35 - 37 ºC. - -20 ºC or colder

- 20 - 24 ºC. Once thawed, cryoprecipitate must be kept at room temperature (20 - 24oC) and used within 6 hours after thawing. If pooled using an open system, cryoprecipitate must be used within 4 hours of thawing (storage temperature 20 - 24oC). All other temperatures listed are outside of the acceptable range.

Platelets should be stored at what temperature? - 1-6 degrees Celsius - Less than -18 degrees Celsius - 20-24 degrees Celsius - 34-37 degrees Celsius

- 20-24 degrees Celsius Platelets should be stored at 20-24 degrees Celsius with continuous gentle agitation. They should be infused within 4 hours after the seal on a platelet unit is broken. Red cells are stored at 1-6 degrees Celsius. Frozen plasma and cryoprecipitated AHF are stored at <-18 degrees Celsius. Frozen plasma and cryoprecipitated AHF are thawed at 34-37 degrees Celsius.

In which of the following sections of CFR Title 21, Good manufacturing practices, would you find requirements for quality control testing of donor units of platelets? - 21 CFR 211.22 Responsibilities of a Quality Control Unit - 21 CFR 211.80 Control of Components, Drug Product Containers and Closures - 21 CFR 606.140 Laboratory Controls - 21 CFR 640.25 Platelets - General Requirements

- 21 CFR 640.25 Platelets - General Requirements The correct answer is 21 CFR 640.25. This section contains the requirement to test a minimum of 4 units per month. The pH must be at least 6.2 at the end of the dating period. The plasma volume and the platelet count must also be measured. The minimum platelet count in a whole blood derived Platelet is 5.5 x 1010 in 75% of the units tested. There are no quality control requirements for platelets in 21 CFR 211.22; 21 CFR 211.80; or 21 CFR 606.140.

Red blood cell units that contain CPD (citrate-phosphate-dextrose) can be stored for up to how many days? - 21 days - 28 days - 35 days - 42 days

- 21 days Red blood cell units that contain CPD or CP2D may be stored for up to 21 days. Irradiated red cell units may be stored for up to 28 days or the original expiration date, whichever occurs first. Red cell units that contain CPDA-1 may be stored for up to 35 days. Red cell units that contain an additive solution may be stored up to 42 days.

When transporting donated platelet units, what is the maximum amount of time that agitation of platelets can be stopped for? - 1 hour - 12 hours - 24 hours - 3 days

- 24 hours Agitation of donated platelet products is necessary for proper gas exchange and to prevent platelet aggregation. This agitation can be periodically discontinued during transportation, but the cessation of agitation cannot exceed 24 hours. Platelet agitation may be ceased for 1 or 12 hours, but neither is the maximum amount of time that cessation may occur. Platelets would not be viable for transfusion if agitation ceased for 3 days.

FFP that has been thawed at 30 - 37°C and maintained at 1 - 6°C must be transfused within ___________ after it has been thawed. - 24 hours - 8 hours - 12 hours - 5 days

- 24 hours FFP that has been thawed at 30-37°C and maintained at 1-6°C must be transfused within 24 hours. After the initial 24 hours have elapsed, thawed FFP and PF24 may be re-labeled as "Thawed Plasma" and stored at 1-6°C for up to 4 more days (not to exceed 5 days). Thawed plasma contains stable coagulation factors (i.e. fibrinogen, prothrombin) but reduced amounts of the following coagulation factors: factor V, VII, VIII, and X. FFP prepared from whole blood units (CPD, CPDA-1, CD2D) must be frozen with 8 hours from collection. PF24 must be frozen within 8-24 hours of collection. The 12-hour time period is not applicable to FFP transfusion practices.

How soon must granulocyte concentrates be administered after donation? - 12 hours - 24 hours - 3 days - 30 days

- 24 hours Granulocyte concentrates deteriorate rapidly and should be transfused as soon as possible and always within 24 hours of collection. Granulocyte concentrates are used only in conditions where the patient has neutropenia and current bacterial or fungal infection(s) that are not responsive to antibiotics or other treatment.

Frozen red blood cells that have been thawed, deglycerolized and reconstituted in an open system must be used within _______. - 1 hour - 24 hours - 14 days - 7 days

- 24 hours The correct answer is 24 hours. Frozen red blood cells that have been thawed, deglycerolized and reconstituted in an open system must be used within 24 hours. 1 hour is an unreasonable amount of time for a unit to be used. If prepared in a functionally closed, FDA-approved system, post-thaw storage would be allowed up to 14 days, but this statement indicates that an open system was used. 7 days is inappropriate since the cells were prepared in an open system.

Unless an alternative has been approved by the FDA, what is the expiration and storage temperature of rejuvenated (non-frozen) RBC's? - 24 hours; 1 °C to 6 °C - 48 hours; 1 °C to 10 °C - 72 hours; 1 °C to 6 °C - 24 hours; Room temperature

- 24 hours; 1 °C to 6 °C The correct expiration date/time after rejuvenation is 24 hours, although rejuvenated RBCs can also be frozen and maintained at -65 °C. If the product is not frozen, it should be stored like other packed RBCs at 1 °C up to 6 °C. In cases where the rejuvenated cells are frozen, the expiration date is 10 years if collected in CPD or CPDA-1. If rejuvenated cells are frozen and collected with AS-1, the expiration date is 3 years.

Antenatal Rh Immune Globulin (RhIG) is typically given at how many weeks gestation? - 20 - 24 - 28 - 32

- 28 Rh Immune Globulin (RhIG) is used to help prevent pregnant women from becoming actively immunized to the D antigen. During pregnancy and delivery, fetal blood can enter maternal circulation. This exposure to the D antigen puts the mother at risk for becoming sensitized and making an anti-D. Rh-negative women carrying an Rh-positive fetus now receive RhIG at 28 weeks (antenatal) and at delivery (within 72 hours of delivery) to clear fetal red blood cells from the maternal circulation. The RhIG can attach to fetal red blood cells, which are then cleared by macrophages. RhIG does not pose a risk to the fetus when given antenatally, but it may cause a positive antibody screen for the mother and a positive DAT for the newborn.

What is the maximum interval during which a recipient sample may be used for compatibility testing if the patient has recently been transfused or was pregnant within the past 3 months? - 24 hours - 3 days - One week - Two weeks

- 3 days If the patient has been recently transfused or pregnant within the past 3 months, then the maximum interval during which a recipient sample may be used for crossmatching is 3 days within the scheduled transfusion. Additionally, the maximum testing interval for compatibility testing is 3 days in cases when relevant medical and/or transfusion history is unknown. Donor and recipient samples are stored for a minimum of 7 days (or one week) following transfusion. Both 24 hours and two-week time intervals are not included in compatibility testing protocols.

Antibody identification interpretations would be considered correct 95% of the time or have a P value of 0.05 (5% probability that the result is due to chance) if you have: - 2 positive reactions to rule in an antibody and 2 negative reactions to rule out an antibody - 1 positive reaction to rule in an antibody and 3 negative reactions to rule out an antibody - 3 positive reactions to rule in an antibody and 3 negative reactions to rule out an antibody - 3 positive reactions to rule in an antibody and 1 negative reaction to rule out an antibody

- 3 positive reactions to rule in an antibody and 3 negative reactions to rule out an antibody A P value is used to statistically determine the probability that a certain set of events or results will happen by random chance. A P value of 0.05 means that there is a 5% chance that the pattern of reactivity is due to something other than the suspected antibody. This can also be interpreted as the data will be correct 95% of the time. Using 3 cells to rule in and 3 cells to rule out gives the highest probability of the above listed answers (P value of 0.05). By comparing the patterns of reactivity and non-reactivity, we can more safely assume that an observed pattern is not the result of chance alone.

What is the expected life span of a normal red blood cell? - 3-4 months - 1-2 months - 3-6 weeks - 1-3 weeks

- 3-4 months The life span of normal red blood cells in the circulation is approximately 120 days (about 4 months). Aging red blood cells are removed primarily via extravascular catabolism. Conditions that cause destruction of red blood cells decreases the normal life span.

Which of the following is the proper temperature to use when crossmatching in the presence of a cold antibody? - 37º C - 25º C - 15º C - 4º C

- 37º C Most antibodies that are inactive at 37º C and active only below 37º C (i.e. cold reactive antibodies) are of little clinical significance. If a nonspecific cold antibody or cold agglutinin is suspected, warm the sample and testing reagents, including saline, to 37º C. Only do reaction readings at AHG; bypassing the optimum reaction temperature prevents activation and binding of the cold antibody.

Delayed hemolytic transfusion reactions (DHTR) usually occur within which time period? - 1 hour after transfusion - 24 hours after transfusion - 3-7 days after transfusion - One year after transfusion

- 3-7 days after transfusion The correct answer is 3 - 7 days after transfusion. Delayed hemolytic transfusion reactions (DHTR) are usually caused by a secondary (anamnestic) response. It takes about 3-7 days from the time of transfusion for enough antibody to be produced to cause clinical symptoms. A hemolytic reaction 1 hour after transfusion would be considered an immediate hemolytic transfusion reaction (IHTR). A transfusion reaction 24 hours after transfusion would likely be a nonhemolytic transfusion reaction (ex. febrile nonhemolytic transfusion reaction). Hemolysis one year after transfusion would most likely be due to something other than the transfusion.

The appropriate dosage of Rh immune globulin (RhIg) to administer post-delivery to an Rh-negative mother delivering an Rh-positive child is calculated based on the estimated volume of fetal bleed. What is the value of x in the formula given below that is used to calculate RhIg dosage? Number of vials of 300 µg RhIg = volume of fetal bleed/x mL - 10 - 30 - 100 - 300

- 30 A 300 µg vial of RhIg can prevent immunization to a fetomaternal hemorrhage (FMH) of 30 mL of D positive whole blood. Using the estimated volume of fetal bleed determined by the Kleihauer-Betke test or flow cytometry, the number of vials of RhIg (300 µg) to inject is calculated as follows:The number of vials of 300 µg RhIg = volume of fetal bleed/30 mL. In the interests of safety some American organizations recommend the following to deal with decimal points:If the number to the right of the decimal point is <5, round down and add 1 vial (e.g., 1.4 = 1 +1 = 2 vials)If the number to the right of the decimal point is greater than or equal to 5, round up and add 1 vial (e.g., 1.7 = 2 +1 = 3 vials).

How many milliliters of Rh positive whole blood is one dose of Rh immune globulin capable of neutralizing? - 15 - 30 - 45 - 450

- 30 One dose of Rh immune globulin, also known as RhoGAM, can neutralize approximately 30 mL of Rh positive fetal whole blood (or 15 mL of Rh positive blood cells). Additional doses may be necessary if the amount of Rh positive whole blood exposure is determined to be greater than 30 mL.

A 300 µg dose of RhIg can suppress immunization up to a maximum of _____ mL of D-positive whole blood. - 15 mL - 20 mL - 25 mL - 30 mL

- 30 mL A 300 µg dose of RhIG can suppress immunization of up to approximately 30 mL of D-positive whole blood or 15 mL of D+ red cells. One vial would be sufficient for fetomaternal bleeds less than 30 mL whole blood as well, including 15 mL, 20 mL, and 25 mL.

One standard 300 µg vial of RhIg contains enough anti-D to protect against what amount of whole blood exposure? - 15 mL - 30 mL - 1 L - 5 mL

- 30 mL The correct answer is 30 mL. A regular dose vial will provide sufficient anti-D to protect against 30 mL of whole blood. A regular dose vial will provide sufficient anti-D to protect against 15 mL of packed RBCs. A microdose of RhIg will provide sufficient anti-D to protect against a loss of pregnancy before the 12th week when total fetal blood volume is estimated to be less than 5 mL.

Rh Immune Globulin (RhIG) is used to prevent the active immunization to the D antigen in women who are Rh negative carrying an Rh positive fetus. One dose of RhIG (equal to 300 µg of World Health Organization reference material) contains enough anti-D to protect against: - 50 mL of whole blood - 50 mL of packed red cells - 30 mL of whole blood - 20 mL of packed red cells

- 30 mL of whole blood Rh Immune Globulin is used to help prevent pregnant women from becoming actively immunized to the D antigen. During pregnancy and delivery fetal blood can enter maternal circulation. This exposure to the D antigen puts the mother at risk for becoming sensitized and making an anti-D. Women who are Rh negative carrying an Rh positive fetus now receive RhIG at 28 weeks and at delivery (within 72 hours of delivery) to clear fetal red blood cells from maternal circulation. The RhIG can attach to fetal red blood cells which are then cleared by macrophages. RhIG has also been used to remove Rh positive red blood cells from Rh negative patients who may have received the Rh positive unit by mistake. This patients are at risk for developing an anti-D and the use of RhIG removes the Rh positive red blood cells from their circulation. One dose of RhIG can protect against 30 mL of whole blood or 15 mL of packed red cells. All other options listed above would require more than 1 unit of RhIG.

Severe blood loss causing circulatory collapse and shock usually first occurs when what percentage of blood is lost? - 5 to 10% - 20% - 30 to 40% - 60%

- 30 to 40% According to McKenzie and Williams (2015), severe blood loss of 30 to 40% of total blood volume leads to circulatory collapse and shock. Acute blood loss of 20% or less, in many cases, doesn't cause clinical symptoms at rest. Because of this 5 to 10% and 20% are not the correct answers. Acute blood loss of 50% or more is not compatible with life, therefore, 60% is not the correct answer. When blood is lost over a longer period of time, the body can develop compensatory mechanisms to accommodate for the loss. Because of this, circulatory collapse and shock may not develop when 30 to 40% of blood is lost over an extended period of time.

What is the increase in the risk for developing antibodies against red cell antigens (RBC alloimmunization) for patients who are characterized as chronically transfused patients? - 1% - 4% - 2% - 8% - 5% - 10% - 30% or greater

- 30% or greater In chronically transfused patients, such as those with thalassemia, autoimmune hemolytic anemia, and sickle cell disease, the risk of developing antibodies against red cell antigens (RBC alloimmunization) increases by 30% or more.

Red cells units containing CPDA-1 as an anticoagulant-preservative may be stored for how long prior to transfusion? - 5 days - 15 days - 25 days - 35 days

- 35 days Red cell units containing CPDA-1 may be stored at 1-6oC for up to 35 days. None of the other choices are associated with storage limits according to current regulations. Red cell units containing CPD or CP2D may be stored for 21 days prior to transfusion. Additive solutions such as AS-1, AS-3, and AS-7 increase the storage limit of red cell units to 42 days.

Donated red blood cells that contain the anticoagulant CPDA-1 (citrate-phosphate-dextrose-adenine) may be stored up to how many days? - 21 days - 28 days - 35 days - 42 days

- 35 days The addition of adenine to the anticoagulant-preservative solution allows the red blood cell unit to be stored for up to 35 days rather than 21 days. CPD or CP2D blood can be stored for up to 21 days. Irradiated red blood cells expire either after 28 days from irradiation or on the original expiration date, based on which date occurs first. Additive solutions increase the shelf life of donated blood products to 42 days.

A potential apheresis platelet donor must be deferred for how long following the use of aspirin? - 4 weeks - 2 weeks - 48 hours - No deferral - can donate immediately given they meet all other requirements.

- 48 hours The correct answer is 48 hours. Because aspirin inhibits platelet function, a potential apheresis platelet donor must be deferred for a minimum of 48 hours after taking aspirin. An apheresis unit of platelets is usually the sole source of platelets when transfused to a patient.4 weeks is incorrect. Certain vaccinations may be cause for a 4-week deferral from donating whole blood and/or other blood products.2 weeks is incorrect. The use of certain antiplatelet function medications such as clopidogrel and ticlopidine may be cause for a 2-week deferral from donating apheresis platelets. When donating a unit of whole blood, there is no restriction due to aspirin ingestion.

In a closed system, thawed FFP and PF24 blood components may be labeled as "Thawed Plasma" 24 hours after the original thaw time and given a shelf life of? - 5 days - 60 minutes - 24 hours - 2 days

- 5 days Thawed FFP and PF24 components expire within 24 hours from the date and time thawed. After 24 hours have elapsed from the date of thawing, thawed FFP and PF24 components may be labeled as "Thawed Plasma" and allowed a 5-day shelf life. One full day is the equivalent of 24 hours from date/time of thawing and the 60 minute time-frame is not applicable to this component type.

What is the maximum number of white blood cells allowed in a leukocyte-reduced unit of red blood cells? - 5 x 10 6 - 1 x 10 10 - 5.5 x 10 10 - 3 x 10 11

- 5 x 10 6 A unit of leukocyte-reduced red blood cells cannot contain more than 5.0 x 106 white blood cells. A unit of apheresis granulocytes must contain at least 1.0 x 1010 white blood cells. A unit of platelets must contain at least 5.5 x 1010 platelets. Leukocyte-reduced apheresis platelets must contain at least 3.0 x 1011 platelets in at least 90% of the units tested.

What is the maximum number of white blood cells that may be present in 95% apheresis platelet units that have been leukocyte-reduced? - 1.0 x 10 10 - 3.0 x 10 11 - 5.0 x 10 6 - 5.5 x 10 10

- 5.0 x 10 6 95% of apheresis platelets tested must contain a maximum of 5.0 x 106 residual white blood cells to meet the quality control requirement. Apheresis granulocyte units must contain at least 1.0 x 1010 or more white blood cells. A unit of apheresis platelets must contain at least 3.0 x 1011 or more platelets in 90% of the units tested. A unit of platelets must contain at least 5.5 x 1010 platelets or more in 90% of the units tested.

If parents have the blood group genotypes AA and BO, what is the possibility of having a child with a blood type of A? - 25% - 50% - 75% - 100%

- 50% The parents will each give one of their ABO genes, so the possibilities are as follows: AB, AO, AB, AO = 50% chance of A (AO genotype) blood type and 50% chance of AB blood type. B O A AB AO A AB AO

In order to prevent a loss of viability in platelet concentrates during storage, the pH must be maintained at or above what level? - 7.5 - 6.2 - 5.0 - 4.5

- 6.2 The correct answer is 6.2. The proper pH for a unit of platelets must be at or above 6.2. 7.5 is incorrect because all of the pH values between 6.2 - 7.5 are also acceptable. 5.0 and 4.5 are incorrect because they are values below the lower cutoff of 6.2.

A standard blood donation of 450-500 mL requires a minimum anticoagulant-preservative solution volume of: - 57 mL - 63 mL - 70 mL - 82 mL

- 63 mL The minimum volume of 63 mL of anticoagulant-preservative ensures that the donated blood product contains an appropriate anticoagulant-to-blood ratio. 57 mL of anticoagulant-preservative will not allow the donated blood unit to have enough anticoagulant to ensure a proper anticoagulant-to-blood ratio. 70 mL of anticoagulant-preservative is the maximum volume allowed to ensure proper anticoagulant-to-blood ratio. 82 mL of anticoagulant-preservative is too high and will result in an improper anticoagulant-to-blood ratio.

Donor and recipient blood samples must be kept for at least how long after transfusion? - 10 days - 7 days - 3 days - 24 hours

- 7 days The correct answer is 7 days. Donor and recipient samples must be available to investigate a transfusion reaction, if necessary. Samples used for antibody screening and serological crossmatches must be less than 72 hours (3 days) old, but the sample must be kept the full 7 days. 5 days is not long enough to retain a sample in case of a transfusion reaction workup. 10 days is in excess of the required retention time of 7 days.

If possible, what is the recommended time interval for Rh immune globulin administration to the Rh negative mother following the delivery of an Rh positive or weak-D positive infant? - 72 hours - One week - Two weeks - Prior to another pregnancy

- 72 hours The Rh negative nonimmunized mother should receive RhIg soon after delivery of an Rh positive baby. Based on experiments conducted many years ago, the recommended interval is within 72 hours after delivery. Even if more than 72 hours have elapsed, RhIg should still be given, as it may be effective and is not contraindicated.

The A1 subgroup represents approximately what percentage of group A individuals? - 25 - 30% - 50 - 60% - 75 - 80% - 95 - 98%

- 75 - 80% The A1 phenotype exists in about 80% of all group A individuals. The A2 phenotype constitutes about 20% of group A individuals. All the other subgroups consist of less than 1% of all group A individuals.

Platelets that are not collected by an apheresis method must be prepared within ________ of the collection of whole blood. - 30 minutes - 8 hours - 24 hours - 48 hours

- 8 hours Platelets that are not collected by an apheresis method must be prepared within 8 hours of the collection of whole blood (WB). The WB must not be cooled below 20oC prior to the preparation of platelets. The other time frames listed are not in line with current platelet preparation practices from units of WB. Apheresis platelets would be prepared according to the apheresis instrument manufacturer's instructions. Both WB and apheresis-derived platelets are stored at 20 -24oC.

The accepted interval between whole blood donations is: - 2 days - 4 weeks - 8 weeks - 16 weeks

- 8 weeks The mandatory waiting period between whole blood donations is 56 days, or eight weeks. Donors must wait at least two days between plasmapheresis, plateletpheresis, or leukopheresis. Infrequent plasmapheresis has a waiting period of four weeks between donations. The waiting period for double, or two-unit, donations of red cells is 16 weeks.

Which of the following represents the approximate percentage of the Caucasian population that is Rh-positive? - 35 % - 65 % - 85 % - 95 %

- 85 % Rh-positive and Rh-negative refer to the presence or absence of the D antigen on an individual's red blood cells. The D antigen is very immunogenic (most immunogenic outside of ABO antigens) and is therefore clinically significant (causes transfusion reactions and hemolytic disease of the fetus and newborn). Approximately 85% of Caucasian individuals are Rh-positive, while approximately 15% of Caucasian individuals are Rh-negative. In the African American population, approximately 92% of individuals are Rh-positive and 8% are Rh-negative.

A unit of leukocyte-reduced red blood cells must retain at least what percentage of red blood cells following leukoreduction? - 65% - 75% - 85% - 95%

- 85% The American Association of Blood Banks (AABB) standards state that a unit of leukocyte-reduced red blood cells must contain at least 85% of the red cells as the original unit. Units containing 65% or 75% of red blood cells would not meet this standard of quality. Units containing 95% of red blood cells exceed the minimum standard, not the minimum percentage required for red blood cells following leukoreduction.

If an average-weight adult male patient with a 7 g/dL hemoglobin is given two units of packed cells, what would be the approximate new hemoglobin value (assuming there is no active bleeding or other predisposing factors that would shorten the survival of the blood cells)? - 7.5 g/dL - 8.0 g/dL - 9.0 g/dL - 11.0 g/dL

- 9.0 g/dL One unit of Red Blood Cells increases the hemoglobin level by approximately 1g/dL in an adult who is not actively bleeding and has no other predisposing factors that would shorten the survival of the transfused blood cells. In this question, the patient was given 2 units of packed cells, so the expected increase in hemoglobin would be 2g/dL.

What is the minimum volume (milliliters) of Rh positive red blood cells that would be needed to produce anti-D in an Rh negative individual? - < 0.1 mL - 1 mL - 5 mL - > 10 mL

- < 0.1 mL Rh antigens are highly immunogenic; the D antigen is the most potent. Exposure to less than 0.1 mL of Rh positive red blood cells can stimulate antibody production in a Rh negative person.

Following a major trauma event, a family of four walks into your donor center hoping to donate blood. Which one of the following individuals may donate blood today? - A 14-year-old girl who received an ear piercing 6 weeks ago. - A 53-year-old man who worked and resided in the United Kingdom from 1983-1989. - A 49-year-old woman who donated whoe blood 5 weeks ago. - A 22-year-old woman using oral contraceptives.

- A 22-year-old woman using oral contraceptives. The 22-year-old female is the only one who may donate blood based on the information provided because there are no restrictions on women using oral contraceptives or other birth control methods. The 14-year-old girl cannot donate blood because an individual must be at least 16 years of age to donate blood. Additionally, there is a 12 month waiting period to donate blood following a body piercing, unless she has donated within the past 12 months and the piercing was administered with single-use equipment. The 53-year-old man may not donate blood because residing in the UK for > 3 months from 1980 to 1996 is considered a risk factor for Creutzfeldt-Jakob disease. The 49-year-old woman may not donate blood because an individual must wait 8 weeks between whole blood donations.

A rosette test to screen for fetomaternal hemorrhage (FMH) is indicated in all of the following situations, EXCEPT: - A weak D-positive infant - A D-positive infant - A D-positive mother - A D-negative mother

- A D-positive mother The correct answer is a D-positive mother. The mother should be D-negative and the infant should be D-positive or weak-D positive.

Which best describes an A1 individual? - A antigens on RBCs and anti-B antibodies in serum, which may also contain anti-A1 antibodies. - A, A1, and B antigens on RBCs and no antibodies in serum. - B antigens on RBCs and anti-A antibodies in serum. - A and A1 antigens on RBCs and anti-B antibodies in serum.

- A and A1 antigens on RBCs and anti-B antibodies in serum. Group A1 has A1 and A antigens on the red blood cells and anti-B in the serum. Group A2 has A antigens on the red blood cells with anti-B and possibly anti-A1 antibodies in the serum. Group A1B has A and B antigens on the red blood cells with neither anti-A nor anti-B in the serum. Group B has B antigens on the red blood cells and anti-A in the serum.

If the parents are group A and B respectively, what are the possible blood groups of their children? - A and B only - A and B and AB only - A and B and O only - A and B and AB and O

- A and B and AB and O If the parents are phenotypes A and B, then their possible allele combinations are genotypes AA or AO and type BB or BO. The following blood types are possible when one allele from each parent is passed to the child: AO and BO parents = possibility of phenotypes (and genotypes) AB (AB), A (AO), B(BO), or O(OO) children AO and BB parents = possibility of phenotypes (and genotypes) AB(AB) or B(BO) children AA and BO parents = possibility of phenotypes (and genotypes) AB(AB) or A(AO) children AA and BB parents = possibility of phenotypes (and genotypes) AB(AB) only children Since we do not know the parents' allele combination, the best answer choice is A and B and AB and O.

Your screen cells are 3+ at immediate spin and weak (W)+ at AHG. Your autocontrol is negative for both phases. Some of your antibody panel cells are 3+ at immediate spin and negative at AHG. What should you suspect? - A warm autoantibody is present - A cold antibody may be present - Bad specimen draw - A warm reacting alloantibody

- A cold antibody may be present If your reactions are strong at immediate spin (3+) and then get weaker at AHG (w+), it could mean the presence of a strong cold antibody. Cold antibodies tend to be IgM and their optimum phase for reactivity is immediate spin. Incubation and washing of the sample may cause the agglutination that occurred at room temperature to break down. This would appear as a weaker reaction at AHG. If the reaction strengths varied in each panel cell then that could be an indication that there are multiple antibodies present or dosage (stronger reaction with homozygous cells compared to heterozygous cells) occurring. The autocontrol is negative at all phases so the presence of an autoantibody is unlikely. The reaction strength decreases as the temperature increases (immediate spin stronger than AHG) suggests that the antibody present in not a warm reacting antibody. Lastly, based on the given results there is no indication that the specimen draw was compromised.

Which one of these physical exam results would cause a donor to be deferred? - A hemoglobin of 13.0 g/dL. - A pulse of 75 - A diastolic blood pressure of 110 mm Hg - A temperature of 99.3 ºF

- A diastolic blood pressure of 110 mm Hg The correct answer is a diastolic blood pressure of 110 mm Hg. Donors must have a diastolic blood pressure must be less than 100 mm Hg. Donors must have a hemoglobin greater than or equal to 12.5 g/dL. Donors must have a pulse between 50-100 beats per minute. Donors must have a temperature at or below 37.5°C (99.5°F).

All of the following steps should be taken in the IMMEDIATE investigation of a potential hemolytic transfusion reaction EXCEPT: - DAT on the post-transfusion patient sample. - Check for clerical errors. - Visual examination of the post-reaction and pre-reaction plasma for hemolysis. - A gram-stain on the patient's plasma.

- A gram-stain on the patient's plasma. For the investigation of a hemolytic transfusion reaction, a clerical check, visual check for hemolysis, and a DAT are indicated. If any of these yields a discrepancy or evidence of hemolysis/serologic incompatibility, further testing will be performed. A gram-stain on the patient's plasma is not indicated. If sepsis is suspected, a gram-stain and culture of the donor unit may be performed.

A patient is group AB with one copy of the Se gene. What antigens will they have in their secretions? - A, B, & H - Only B & H - Only A & H - Only H

- A, B, & H A, B, and H antigens are found on red blood cells, but they can also be found in secretions if the individual has at least one copy of a secretor gene (Se). The Se gene codes for a transferase that modifies type I precursors in secretions to form H. Once H is formed, immunodominant sugars can be added to produce A and B antigens in secretions. In this question, AB patients who are secretors will have A, B, and H substances secreted. Group B patients who are secretors will have both B and H substances secreted. Group A patients who are secretors will have both A and H substances secreted. Group O secretors will only secrete H substance.

A 47-year old man is hemorrhaging severely. He is group AB, Rh (D) negative. Ten units of packed red blood cells are requested STAT. One group-specific unit is available. Which other units that are available in the blood bank would be most appropriate to choose for crossmatching? - B, Rh(D) - positive - A, Rh(D) - negative - A, Rh (D) - positive - O, Rh (D) - positive

- A, Rh(D) - negative Rh-negative recipients should receive Rh-negative Red Blood Cells. A group AB patient can receive Group AB, A, B, or O blood. If AB negative blood is not available, the next units selected should be A negative because A is the second most common ABO blood type. The second choice should be B negative. O negative should be used last because it is the only blood type available for an O negative recipient and is used as the 'emergency' blood type. Therefore, the best choice would be units that are A negative. Transfusion of Rh-positive blood to Rh-negative male patients is possible IF the patient has NO preformed anti-D in their serum. Nearly 80% of Rh-negative patients transfused with 200 mL or more of Rh-positive blood will produce anti-D. This should only occur when Rh-negative units are not available, and the risk of not transfusing is greater than the risk of transfusing.

Which one of the following blood groups usually reacts LEAST strongly with anti-H? - 0 - B - A2 - A1

- A1 The amount of H antigen found on red cells is at its greatest amount on O cells, followed by A2, B, A2B, A1, and A1B. Of the blood groups that are listed, A1 has the least amount of H antigen and therefore would react least strongly with anti-H.

Which of the following is the most common subgroup of A? - A1 - A2 - A3 - Ax

- A1 The group A phenotype is classified into two major subgroups: A1 and A2. The A1 phenotype exists in about 80% of group A individuals. The A2 phenotype exists in about 20% of group A individuals. Although more infrequent than A1 and A2, other subgroups that collectively have a frequency of less than 1% include Aint, A3, Ax, Am, Aend, Ael, and Abantu.

The plant lectin obtained from the Dolichos biflorus plant will agglutinate which of the following? - B cells - O cells - A2 cells - A1 cells

- A1 cells Anti-A1 lectin is extracted from the seeds of Dolichos biflorus. This reagent will agglutinate A1 cells and A1B cells but not A2 cells. Anti-B lectin is extracted from the plan Bandeiraea simplicifolia. This reagent would agglutinate any blood type with the B antigen.

Which of the following blood groups reacts least strongly with anti-H? - O - A2 - A1 - A1B

- A1B The amount of H antigen present on red cells varies by blood group: O > A2 > B > A2B > A1 > A1B. Therefore, the A1B would have the weakest of the reactions with anti-H since it has the least amount of H antigen.

Which of the following statements regarding the ABO phenotype A2 is true? - A2 cells contain more antigens per RBC than A1 cells. - A2 antigens are linear while A1 antigens are branched. - A2 RBCs will agglutinate with anti-A1 lectin (Dolichos biflorus). - A2 cells will not agglutinate with anti-A antisera used for ABO blood typing.

- A2 antigens are linear while A1 antigens are branched. A2 antigens are linear versus A1 antigens are branched. Because of this, A1 cells have more antigens on the surface of their RBC's (approximately 4x more).A2 cells do NOT agglutinate when mixed with anti-A1 lectin (Dolichos bifluros). A1 cells will agglutinate with anti-A1 lectin.Both A1 and A2 RBCs will agglutinate with anti-A antisera used for ABO blood typing.

The serum of which of the following individuals may agglutinate group A1 cells? - A2 individual - A1B individual - A1individual - Newborn

- A2 individual Approximately 4% of individuals with A2 blood type will have Anti-A1 antibodies in their serum. Individuals with some rarer A subgroups may also have Anti-A1 in their serum. Agglutination will occur if the serum from any of these individuals is mixed with A1 red cells. An A1B or an A1 individual would not be expected to produce anti-A1. A newborn would not typically have yet formed any naturally occurring ABO antibodies.

Units of A-negative, B-negative, and O-negative red blood cells are shipped to your transfusion service. What testing MUST be performed by your facility before placing these units into your inventory? - ABO - ABO and Rh - ABO, Rh and antibody screen - ABO, Rh and Weak D to confirm negative status

- ABO and Rh All donor Red Blood Cell units must have the ABO group re-confirmed. Units that are labeled as "Rh-negative" must also be tested and re-confirmed for Rh negativity. Antibody screen testing is not performed on donor units upon receipt to inventory. Tests for weak D are not required upon unit type reconfirmation/receipt to inventory.

What is the correct blood group for the patient based on the reactions below? Forward (Cell) Typing Anti-A = 4+ Anti-B = 4+ Reverse (Serum) Typing A1 Cells = 0 B Cells = 0 - AB - O - A - B

- AB Group AB patients will have both the A antigens (which reacts with anti-A reagent) and B antigens (which reacts with anti-B reagent) on their red blood cells. These patients will NOT have anti-A (which reacts with A1 cells) or anti-B (which reacts with B cells) in their serum because those antibodies will go against their own red blood cell antigens. Group O patients will not have A or B antigens on their cells and will have negative reactions with anti-A or anti-B, but they will have anti-A and anti-B in their serum, which will give positive results with A1 cells and B cells. Group A patients will have A antigens but not B antigens on their cells and will have a positive reaction with anti-A, but not anti-B. They will not have anti-A in their serum, but they will have anti-B in their serum, which will give negative results with A1 cells and positive results with B cells. Group B patients will not have A antigens but will have B antigens on their cells and will have no reaction with anti-A but a positive reaction with anti-B. They will have anti-A in their serum, but they will not have anti-B in their serum, which will give positive results with A1 cells and negative results B cells. This is expected results for Group AB

What are the possible ABO genotypes of offspring of parents whose genotype is AA and BB? - AB - AO - BO - OO

- AB In this case, the only blood type inheritance possible is AB, as one parent (AA) has given the A gene, and the other parent (BB) is giving the B gene. There isn't an "O" available from either parent, so none of the other genotypes are possible.

Using the information provided in the table below, interpret the correct ABO blood type. Red Cells Tested With Known Antisera: Anti-A Anti-B Anti-A,B 4+ 4+ 4+ Serum Tested With Known Red Cells: A1 Cells B Cells 0 0 Interpretation of ABO Group: ? - A1 - O - AB - Results are inconclusive; re-testing required.

- AB In this case, the patient's red blood cells reacted with anti-A, anti-B, and anti-A,B antisera. Based on the patients' forward type, the results lead to an interpretation of the blood type, AB. The reverse type confirms the forward type as neither anti-A or anti-B antibodies were detected in the patient's serum with the known red cells. The final interpretation for this patient is blood group AB. Type A (A1) blood would have a strong positive reaction with Anti-A and Anti-A,B, but a negative reaction with Anti-B. The reverse reaction would have a negative reaction with A1 cells and a positive reaction with B cells. Type O blood would have negative reactions with Anti-A, Anti-B, and Anti-A,B on the forward typing and positive reactions with A1 and B cells on the reverse typing.

What ABO phenotype will exist in an individual that inherits an A gene from one parent and a B gene from the other? - A - B - AB - O

- AB The majority of blood group antigens are inherited in an autosomal codominant manner. In this pattern of inheritance, the phenotype of each allele will be present. Since the individual inherited an A allele and a B allele, the individual's phenotype will be AB. The individual will not only demonstrate an A allele as the A and B are codominant. The individual will not only demonstrate a B allele as the A and B are codominant. A and B are both dominant over O. Therefore, in order for an individual to have an O phenotype, the O gene must be inherited from both parents.

Anti-A= 4+ Anti-B= 4+ A1 cell= NT B cell= NT Interpretation of ABO group= ? Given the above results, what is the newborn's ABO group? (NT = not tested) - O - A - AB - Invalid because the reverse testing was not performed.

- AB The newborn has a forward ABO blood group testing result of Group AB. The newborn's ABO blood group is valid. Most laboratories will not do reverse testing on newborn samples because newborns do not produce ABO antibodies until 4 to 6 months and any antibodies present are likely to be of maternal origin.

Which of the following fresh frozen plasma ABO types would be suitable for transfusion to an AB negative patient? - AB negative only. - O negative only. - AB negative and AB positive only. - O negative and O positive only.

- AB negative and AB positive only. FFP should be ABO compatible with the patient's red blood cells. It can be given without regard to Rh type because it does not contain cells with the D antigen for the recipient to react to. Additionally, donors are screened for clinically significant antibodies, so Rh-negative donors should not have anti-D in their plasma. In this case, the recipient is group AB, so they have both A and B antigens on their red cells. The only ABO group without naturally occurring antibodies to the A or B antigen is group AB. This patient can receive AB positive and AB negative fresh frozen plasma. AB negative plasma can be given to this patient, but this answer is incorrect since AB positive plasma can be given as well. Group O plasma (Rh positive and Rh negative) cannot be given since group O plasma has anti-A, anti-B, and anti-A,B. These naturally occurring ABO antibodies would cause an acute hemolytic transfusion reaction in this patient.

Which genotype(s) is/are possible for a mating of an AB mother and an AB father? - AB only - AA and BB - AB, AA, and BB - All genotypes are possible

- AB, AA, and BB The mother will give either an A gene or a B gene to the offspring. The father will give either an A gene of a B gene to the offspring. The only combinations will be AB, AA, and BB and all three are possible. All genotypes would not occur because the O gene was not available from either parent. Also, for each mating there are only 4 combinations that can occur and there are 6 possible genotypes (AA, AO, BB, BO, AB, OO).

The direct antiglobulin test (DAT) is most unreliable when diagnosing hemolytic disease of the fetus and newborn due to which blood group system? - ABO - Duffy - Rh - Kidd

- ABO The correct answer is ABO. In ABO HDFN, the DAT result is neither strongly nor consistently positive. The DAT is usually reliable for antibodies in the Duffy, Rh and Kidd antibody systems.

When processing umbilical cord blood samples for hematopoietic progenitor cells (HPC), what tests are performed on both the mother's blood and cord blood? - ABO & Rh - HIV-1 & HIV-2 - HBV & HCV - HTLV-I & HTLV-II

- ABO & Rh Umbilical cord blood requires special processing. Both the mother's blood sample and the cord blood are tested for ABO and Rh. The maternal sample will have an antibody screen performed along with testing for HIV-1 & HIV-2, HBV & HCV, and HTLV-I & HTLV-II. Also, HBsAg, anti-HBc, and syphilis status is determined. The cord blood is cultured for cytomegalovirus.

Cold agglutinin disease (CAD) is most often associated with which antibody? - Anti-D - Anti-M - Autoanti-I - Autoanti-i

- Autoanti-I In CAD, patients may have a history of mild anemia, Mycoplasma pneumoniae infection, or infectious mononucleosis. The autoantibody specificity in CAD is most often autoanti-I and less commonly autoanti-i.

Which of the following is the most important factor in determining the immediate outcomes of kidney transplants? - ABO compatibility - HLA compatibility - Rh compatibility - Other blood group system compatibility (Kell, Kidd, and Duffy)

- ABO compatibility When determining the immediate outcomes of kidney transplants, ABO compatibility is the most important factor. Transplanted ABO-incompatible tissue comes into continuous contact with the recipient's ABO antibodies. Kidney transplants are not routinely HLA matched. Unless the patient has developed anti-D, Rh compatibility would not be an important factor determining kidney transplant outcomes. Other blood group system compatibility would not be considered the most important factor when determining immediate outcomes of kidney transplants.

What is the cause of MOST severe acute hemolytic transfusions reactions? - Rh incompatibility - ABO incompatibility - Cold agglutinins - Delayed hypersensitivity

- ABO incompatibility ABO incompatibility is the likely cause of an acute hemolytic transfusion reaction. Incompatibility in blood groups other than ABO may also cause acute hemolysis, but the reactions are rare and not usually as severe. Most cold agglutinins do not cause hemolysis, aside from the very rare occurrence of a pathologic cold hemagglutinin disease. By nature, a delayed hypersensitivity reaction is not acute, and cause less-severe extravascular RBC destruction.

If the unit is going to be transfused within the collection facility, autologous blood must always be tested for which of the following before transfusion? - ABO, Rh - ABO, Rh, HBsAg - ABO, Rh, HIV - ABO, Rh, HBsAg, HIV

- ABO, Rh Autologous units must have ABO and Rh grouping determined by the collection facility. Additional testing (unexpected antibodies and infectious disease testing) are not required if the unit is going to be transfused within the collection facility. If the unit gets shipped outside of the collection facility the additional testing will be required. In this question the HBsAg and HIV tests will only be required if the unit is being used outside of the collection facility.

A false-negative reaction while performing the DAT technique may be the result of: - Red cell/AHG tube is over centrifuged - Blood collected in tube containing silicone gel - Saline used for wash stored in glass or metal container - AHG addition delayed for 40 or more minutes

- AHG addition delayed for 40 or more minutes AHG must be added immediately after washing to prevent the possibility of a false negative; a false negative can occur in this situation because previously bound globulins may dissociate from red cells, leaving insufficient antibody coating on the red cells to produce a reaction, or free antibody may directly neutralize antiglobulin reagent. Overcentrifugation, use of tubes containing silicone gel, and use of saline stored in glass or metal container can all result in false-positive results.

Which of the following is a possible type for an offspring from the mating of an O and an AB (non-cis) individual? - AB - AO - BB - OO

- AO AO and BO genotypes are the only possible types for the offspring. In this case, the parents' genotypes are OO and AB, therefore one parent can only pass on the O gene and the other parent can either pass the A or the B gene, but not both. This is illustrated below with the use of the Punnett square. Thus, the heterozygous genotype AB is not possible and the homozygous BB and OO genotypes are not possible. OO x AB O O A AO AO B BO BO

If a child's phenotype is Group O, the phenotype of the mother of the child is Group A and the phenotype of the father is group B, what are the possible genotypes of both parents? - AA and BO - AO and BB - AO and BO - AA and BB

- AO and BO The only mating genotypes that would produce a phenotype of O are AO and BO if the mother is phenotype A and the father is phenotype B. A O B AB BO O AO OO

Which group of conditions increases the risk of HbS polymerization? - Acid pH, dehydration, decreased level of 2,3-DPG - Alkaline pH, dehydration, increased level of 2,3-DPG - Acid pH, dehydration, increased level of 2,3-DPG - Alkaline pH, dehydration, decreased level of 2,3-DPG

- Acid pH, dehydration, increased level of 2,3-DPG The risk of HbS polymerization is enhanced by a low (acid) pH, a state of dehydration, and increased levels of 2,3-DPG. Increased temperature (above 37°C) also adds to the risk.

The AABB Standards for Blood Banks and Transfusion Services requires a control system for antiglobulin tests interpreted as negative. What is done for this control system? - Running tests in duplicate. - Adding an extra incubation. - Adding IgG sensitized red cells. - Performing a minimum of 3 extra washes.

- Adding IgG sensitized red cells. The addition of IgG sensitized red cells to negative AHG (anti-human globulin) tests is required for antibody detection and crossmatch procedures. IgG sensitized red cells were designed as an additive system for negative antiglobulin tests to control the possibility of false negative results. On addition to a negative AHG test, the IgG sensitized red cells should react with the AHG reagent and show agglutination.

A 54-year-old woman has just braved a winter snow storm in North Dakota to see her doctor for a general checkup. She indicates no complaints but does mention how difficult the cold weather is for her. The doctor notices bluish coloring of her ears and fingers. She states that this has been happening for years whenever it is cold and that the problem subsides during the warm summer months. What abnormal test results might be noted in this patient's blood tests? Choose the BEST answer. - Negative Donath-Landsteiner test - Agglutination on blood smear - Positive direct antiglobulin test (DAT) - Agglutination on blood smear and positive DAT

- Agglutination on blood smear and positive DAT The patient demonstrates symptoms of cold agglutinin disease (CAD), which is associated with the presence of a cold autoantibody. The cold autoantibody is typically autoanti-I, and it agglutinates red cells in peripheral areas of the body exposed to cold temperatures. The problem will thus occur seasonally. The mechanism is as follows: When blood reaches the periphery and cools, the autoantibody attaches to RBCs (thus the positive DAT result). This also causes agglutination of RBCs and complement fixation (leading to a mild degree of hemolysis). The patient typically remains stable as this is a chronic condition. The Donath-Landsteiner test helps to diagnose Paroxysmal Cold Hemoglobinuria, which causes symptoms like those noted in this patient. However, note that while the question asks for the "abnormal test results", the answer choice indicates a Negative Donath-Landsteiner test, which is normal.

When preparing platelet concentrates from whole blood, after the second spin and excess plasma has been expressed from the platelets, what is the next step in platelet preparation? - Allow the platelets to rest for 1-2 hours at 20-24°C. - Agitate the platelets vigorously for 1-2 hours at 20-24°C. - Pool several platelet concentrates together immediately and irradiate. - Freeze the platelet concentrate immediately at < 18°C.

- Allow the platelets to rest for 1-2 hours at 20-24°C. After the second spin in the preparation of platelets, the excess plasma is expressed, leaving approximately 50-70 mL of plasma on the packed platelet concentrate. The platelet bag should be allowed to rest at 20-24°C for 1 - 2 hours. After resting, the platelet component can be gently massaged if needed to resuspend the platelets, and the bag is placed on a rotator for gentle agitation. Platelet concentrates should never be vigorously agitated. Platelet concentrates have to be processed as above, and all testing completed before they can be pooled together for transfusion and may/may not need to be irradiated depending upon the recipient's needs. Platelet concentrates are not frozen.

Which of the following individuals is a candidate to receive RhIg? - An Rh positive mother upon delivery of her 3rd child. - An Rh negative mother upon delivery of her first child. - An Rh negative mother who had previously developed anti-D. - An Rh positive mother who miscarried after 2 months.

- An Rh negative mother upon delivery of her first child. Rh-negative mothers are candidates to receive RhIg to prevent the formation of immune anti-D. Administration of RhIg should be done both antepartum and post-partum of first and all subsequent pregnancies. Rh-negative individuals who have already produced immune anti-D are not candidates to receive RhIg. Rh-positive individuals are not candidates to receive RhIg.

A febrile nonhemolytic transfusion reaction is characterized by which of the following? - An increase in temperature of >1oC above 37oC during transfusion - Appearance of hives - Fever above 37oC which develops 24 hours later - A decrease in temperature of < 2oC below 37oC following transfusion

- An increase in temperature of >1oC above 37oC during transfusion One of the febrile nonhemolytic transfusion reactions (FNHTR) symptoms is a >1oC rise in temperature above 37oC, associated with transfusion. Other symptoms include chills, rigors, headaches and vomiting. In allergic transfusion reactions, one of the symptoms is hives and itching within 15-20 minutes of transfusion. In delayed hemolytic transfusion reaction, the symptoms can occur >24 hours to 28 days. Since it is a febrile reaction, there would not be a decrease in temperature.

All of the following are cause for donor deferral EXCEPT? - An individual weighs 115 pounds at the time of donor screening. - Potential donor is currently pregnant in her second trimester. - Donated a whole blood product within the last 30 days. - He/she lived in the United Kingdom (UK) for a consecutive 12-month period between 1980 - 1996.

- An individual weighs 115 pounds at the time of donor screening. Physical examination requirements include weighing donors prior to donation. To donate a standard unit of blood, an individual must weigh at least 100 pounds. A current pregnancy and recent blood donation within the last 30 days may be deemed as temporary deferrals. An individual that has resided in the United Kingdom (UK) between 1980 through 1996 for more than 3 months (consecutively) may be deferred indefinitely.

If a patient is determined to have type B blood, what antibody would be found in his/her serum? - Anti-A - Anti-B - Anti-A and Anti-B - Anti-O

- Anti-A Individuals who are type B, will have anti-A and will not have anti-B. The reverse is true for type A individuals. In type O patients, both anti-A and anti-B will be present since the patient does not have A or B antigens on their red cells. Finally, type AB individuals will have neither anti-A or anti-B in their plasma. There is no such thing as an Anti-O antibody.

Which of the following has the correct interpretation for the ABO group based on the forward and reverse testing? - Anti-A & Anti-B = negative; A1 cells & B cells = positive; interpretation = group AB - Anti-A = positive & Anti-B = negative; A1 cells = negative & B cells = positive; interpretation = group A - Anti-A = negative & Anti-B = positive; A1 cells = positive & B cells = negative; interpretation = group A - Anti-A & Anti-B = positive; A1 cells & B cells = negative; interpretation = group O

- Anti-A = positive & Anti-B = negative; A1 cells = negative & B cells = positive; interpretation = group A Group A patients will have A antigens, but not B antigens on their cells and will have a positive reaction with anti-A, but not anti-B. They will not have anti-A in their serum, but they will have anti-B in their serum, which will give negative results with A1 cells and positive results with B cells. Group O patients will not have A or B antigens on their cells and will have negative reactions with anti-A or anti-B, but they will have anti-A and anti-B in their serum, which will give positive results with A1 cells and B cells. Group B patients will not have A antigens, but will have B antigens on their cells and will have no reaction with anti-A, but a positive reaction with anti-B. They will have anti-A in their serum, but they will not have anti-B in their serum, which will give positive results with A1 cells and negative results B cells. Group AB patients will have both the A antigens (which reacts with anti-A reagent) and B antigens (which reacts with anti-B reagent) on their red blood cells. These patients will NOT have anti-A (which reacts with A1 cells) or anti-B (which reacts with B cells) in their serum because those antibodies will go against their own red blood cell antigens.

Which of the following is the cause of the most severe life-threatening hemolytic transfusion reactions? - Anti-D - Anti-M - Anti-A, Anti-B, Anti-A, B - Anti-Fya

- Anti-A, Anti-B, Anti-A, B Incompatibility involving the ABO blood group system can cause the most severe type of transfusion reaction (acute, hemolytic). Incompatibility due to non-ABO blood group system antibodies can cause transfusion reactions (delayed) but not typically of the immediate, severe type.

If a patient is determined to have type A blood, what antibody would be found in his/her serum? - Anti-A - Anti-B - Anti-A and Anti-B - Anti-O

- Anti-B Individuals who are type A, will have anti-B and will not have anti-A. The reverse is true for type B individuals. In type O patients, both anti-A and anti-B will be present since the patient does not have A or B antigens on their red cells. Finally, type AB individuals will have neither anti-A or anti-B in their plasma. There is no such thing as an Anti-O antibody.

The following results were obtained at delivery for a pregnant woman who received antenatal RhIg. ABO and Rh typing ABO Forward Group ABO Reverse Group Rh anti-A anti-B A1 cells B cells anti-D* 0 0 4+ 4+ 0 Antibody screen Cells Gel IAT* Screen cell l (R1R1) w+ Screen cell ll (R2R2) 1+ Screen cell lll (rr) 0 * IAT = indirect antiglobulin test Which of the following are possible causes of the positive antibody screen? - Anti-D (passive, from RhIg administration) or an antibody other than anti-D - Anti-D (immune) or Anti-D (passive, from RhIg administration) - Antibody other than anti-D - Anti-D (immune) or Anti-D (passive, from RhIg administration) or an antibody other than anti-D

- Anti-D (immune) or Anti-D (passive, from RhIg administration) or an antibody other than anti-D All causes are possible, although given the history of antenatal RhIg administration, passive anti-D alone is the most likely cause. The screening cells I & II are D positive and screening cell III is D negative, so it could be anti-D (either passive or immune). However, there are other antigens present on the both screening cells I & II, and the corresponding antibodies could give the same results.

Which of the following statements are true about anti-H? - Anti-H does not react with group O cells - Anti-H reacts more strongly with A1 cells than with O cells - Anti-H never reacts with group A cells - Anti-H reacts more strongly with group A2 cells than with group A1 cells

- Anti-H reacts more strongly with group A2 cells than with group A1 cells The H antigen is the precursor for A and B antigens on red blood cells. Transferases add immunodominant sugars to H precursors converting them to A or B antigens. The levels of H vary based on the ABO grouping of an individual due to differences in transferase concentration. The following is the relative amount of H present on the red blood cells based on ABO grouping: O>A2>B>A2B>A1>A1B (O has the most H and A1B has the least) Based of the above relative concentrations the correct answer is that anti-H reacts more strongly with group A2 cells than group A1 cells since A2 cells have more of the H antigen. Group O cells have the highest amount of H so anti-H would react and it would react stronger with the O cells when compared to A1 (due to more H on group O). Lastly, anti-H would react with A cells. A2 cells have the second highest relative concentration of H and would therefore react strongly with anti-H.

Which antibody identified in prenatal specimens is never a cause of hemolytic disease of the fetus and newborn? - Anti-D - Anti-c - Anti-E - Anti-I

- Anti-I Anti-I is a common autoantibody that can be found in virtually all sera. It is benign (not associated with in vivo red blood cell destruction). It is usually a weak, naturally occurring, saline-reactive IgM agglutinin. Rh antibodies are primarily IgG and Rh antigens are well developed early in fetal life. While the D antigen is the most immunogenic, c antigen is the next most likely Rh antigen to elicit an immune response, followed by E, C, and e. Rh antibodies formed by the Rh negative pregnant women coat the fetal red blood cells that carry the corresponding antigens. The coated fetal cells are removed from the fetal circulation (hemolytic disease of the fetus and newborn).

Which antibody is associated with Mycoplasma pneumoniae infection and cold hemagglutinin disease? - Anti-P - Anti-I - Anti-M - Anti-i

- Anti-I M. pneumoniae carries an antigen that resembles the I antigen. Thus, when the body develops an immune response against this antigen, the antibodies may cross-react with the I antigen on red blood cells. Anti-I is also associated with cold hemagglutinin disease. Anti-P may be associated with paroxysmal cold hemoglobinuria. Anti-M can occur naturally and often reacts at room temperature but is not associated with a specific disease. Anti-i is associated with infectious mononucleosis, lymphoproliferative disease, and sometimes with cold hemagglutinin disease.

Which of the following antibodies is most often implicated as a cause of a delayed hemolytic transfusion reaction (DHTR)? - Anti-S - Anti-M - Anti-Fya - Anti-Jka

- Anti-Jka Of the antibodies that are listed, anti-Jka is most often reported as the cause of DHTR. Anti-Jkb is also well documented as a cause of DHTR. The antibody titer of these two antibodies commonly decreases rapidly in vivo, which contributes to the higher incidence of DHTRs. Anti-S has been implicated in severe Hemolytic Transfusion Reactions (HTRs) but less often in DHTRs. Anti-M is more commonly an IgM antibody and even when it reacts at 37°C it rarely causes HTRs. Antibodies that are also implicated in a DHTR include Kell, Rh, and Duffy system antibodies.

Which of the following antibodies usually show enhanced agglutination with the use of proteolytic enzymes? - Anti-M,-N, and -S - Anti-Jka, -Jkb, -C, and -E - Anti-Fya and -Fyb - Anti-K

- Anti-Jka, -Jkb, -C, and -E Enzyme techniques are particularly useful in the identification of antibodies in the Rh system (e.g., anti-C and -E) and in the Kidd system (e.g., anti-Jka and -Jkb). Enzymes destroy some antigens, such as M, N, S, Fya, and Fyb. Therefore the corresponding antibodies would not be detected. Enzymes do not affect the K antigen or antibodies against the K antigen.

In providing crossmatch-compatible blood units, all of the following antibodies are most often clinically insignificant EXCEPT: - Anti-Jkb - Anti-P1 - Anti-M - Anti-Lea

- Anti-Jkb Anti-Jkb is considered a clinically significant antibody. Typically, anti-Jkb presents as an IgG antibody and optimally reacts at 37°C in the IAT phase. Anti-P1 and anti-M (IgM agglutinins) optimally react at 4°C and are not associated with HDFN. Anti-Lea, an IgM antibody, is detected in the immediate spin phase (room temperature) and rarely known to cause HTR or HDN. Crossmatch-compatible units that test negative at 37°C and negative through the antiglobulin phase are considered acceptable for transfusion.

Which one of the following antibodies has been implicated in hemolytic disease of the fetus and newborn (HDFN)? - Anti-I - Anti-K - Anti-Lea - Anti-Leb

- Anti-K Only IgG antibody can cross the placental barrier and enter the fetal circulation to attach to the specific antigen on the fetal red cells resulting in HDFN. IgM antibodies, which are larger than IgG, do not cross the placenta and therefore would not be implicated in HDFN. Of the non-Rh system antibodies, anti-K is considered the most clinically significant in its ability to cause HDFN. Anti-I is a common autoantibody, a saline-reactive IgM agglutinin, and is not associated with in vivo red blood cell destruction. Lewis antibodies (Anti-Lea and Anti-Leb) are generally IgM and do not cross the placenta.

Which of the following is NOT considered a characteristic of paroxysmal cold hemoglobinuria (PCH)? - Patient population: children and young adults - Pathogenesis: following viral infection - Site of hemolysis: intravascular - Autoantibody class: IgM

- Autoantibody class: IgM Characteristics or factors associated with PCH include: - autoantibody class = IgG - patient population = children and young adults - pathogenesis = following viral infection - site of hemolysis = intravascular

If detected in antibody screen testing, which of the following antibodies is NOT considered clinically significant in prenatal patients? - Anti-M - Anti-N - Anti-Leb - Anti-Fya

- Anti-Leb Anti-Leb may be detected in antibody screen testing of prenatal patients; however, this antibody is considered clinically insignificant. It is not indicated in causing hemolytic disease of the fetus and newborn (HDFN). Although rarely seen, both anti-M and anti-N can potentially cause mild to moderate HDFN. The most common clinically significant antibodies noted in prenatal patients include the following: anti-Fya, anti-K, anti-D, anti-E, anti-e, anti-C, and anti-c. These IgG antibodies have been determined to cause moderate to severe HDFN.

A 27-year-old female presents to her physician after suffering a spontaneous abortion. Though rare, which antibody may be the etiological agent? - Anti-P1 - Anti-P - Anti-PP1Pk - Anti-P2

- Anti-P Individuals with the P1k phenotype only express the P and Pk antigens, so they may form an anti-P antibody. This antibody is clinically significant as it can cause spontaneous abortion, but it is a rare phenotype to possess. The Anti-P1 antibody is a cold-reacting antibody that is not clinically significant. Null-type individuals have the P phenotype. The corresponding Anti-PP1Pk can be clinically significant, but it causes hemolysis. The P1 and P2 phenotypes are similar to A1 and A2. Anti-P2 does not naturally exist.

The serum from a patient of African-American descent is reactive with all screening and panel cells. Which antibody directed to a high incidence antigen is most likely to be present? - Anti-Lub - Anti-Jk3 - Anti-U - Anti-Ku

- Anti-U The U antigen is located on glycophorin B, a glycoprotein that carries the S, s, and U antigens in the MNS blood group system. Individuals who are U-negative are also S-s- and are of black descent. This phenotype is never found in the white population. The U antigen is present in more than 99% of the population. Anti-Lub is rarely seen because of the high prevalence of the antigen. The presence of anti-Lub is not associated with a specific ethnicity. Individuals who are Jk(a-b-) can make anti-Jk3. The Jk(a-b-) phenotype is most commonly seen in individuals of Polynesian, Filipino, or Chinese descent. Anti-Ku may be found in immunized individuals who have the Kell null (K0) phenotype. The K0 phenotype is not associated with a specific ethnicity.

The Direct Antiglobulin Test (DAT) is used to detect: - Antibodies sensitizing red cells - Antibodies in the plasma - Antigens coating red cells - Antigens in the plasma

- Antibodies sensitizing red cells The DAT, or direct antiglobulin test, is used to detect antibodies sensitizing RBC's in vivo. Antibodies in the plasma are primarily detected by IAT (Indirect antiglobulin test) methods. Antigens are typically found on the red cells and are detected using specific anti-sera testing.

What do the two and/or three reagent cells used for antibody screening detect? - Antibodies to most white cell antigens - Antibodies to red cell A and B antigens - Antibodies to common alloantigens - Antibodies to most private (low incidence) red cell antigens

- Antibodies to common alloantigens Screening cells licensed by the FDA require an antigen profile capable of detecting most clinically significant red cell antibodies (common alloantibodies). Screening cells are for the detection of preformed red cell antibodies. Screening cells are group O, and will, of course not detect antibodies to A and B antigens. Private antigens are low incidence, and screening cells are unlikely to be positive for them. Blood group antigens required on the screening cells include D, C, E, c, e, M, N, S, s, P1, Lea, Leb, K, k, Fya, Fyb, Jka, and Jkb.

What is the most prudent step to follow to select units for crossmatch after recipient antibodies have been identified? - Perform DAT on patient serum and donor units - Antigen type patient cells and any donor cells to be crossmatched - Perform IAT on patient cells and donor units - Obtain a different sample for repeat antibody panel testing

- Antigen type patient cells and any donor cells to be crossmatched After any significant antibodies have been identified, the technologist must antigen type any blood cell units for the recipient along with a cross-match to prevent transfusion reactions. The DAT is for the detection of in vivo sensitization of red blood cells. The IAT was already performed on the patient's serum through the screen to detect unusual antibodies and the antibody identification panel. There is no need to repeat the antibody panel testing since the antibody has been identified.

Which of the following best describes a transfusion reaction: - Any adverse event associated with the transfusion of blood components - A fever associated with a transfusion - The destruction of transfused red cells - The development of a rash after transfusion

- Any adverse event associated with the transfusion of blood components A transfusion reaction can be defined as any adverse event occurring during or after the transfusion of blood components. This event may or may not include a fever, the destruction of transfused red cells, or the development of a rash.

How can a hematoma from venipuncture be prevented? - Apply pressure to venipuncture site immediately after drawing blood - Do not allow the needle to fully penetrate the upper wall of the vein - Leave on tourniquet until after removing the needle - Mix the tubes immediately after blood collection

- Apply pressure to venipuncture site immediately after drawing blood A hematoma can result from blood leaking into the surrounding tissue during a venipuncture. To help prevent this from occurring, pressure should be applied to the venipuncture site immediately after blood collection. The needle should penetrate the upper wall of the vein, but it should not completely penetrate the vein. Not penetrating the upper wall completely or penetrating both the upper and lower walls can allow blood to seep into the surrounding tissue, causing a hematoma. The tourniquet should be removed before the needle. Not doing so allows blood to pool from the vein into the surrounding tissue, causing a hematoma. Mixing the tubes after blood collection has no effect on the formation of a hematoma.

Leukocyte reduction may be performed at the same time as which step in blood component collection? - During the initial light spin - At the same time the additive solution is added - During the heavy spin - During the preparation of fresh frozen plasma

- At the same time the additive solution is added Leukocyte reduction can be performed at the same time as the additive solution is added if an additive solution is used. The light spin creates a platelet-rich plasma. White blood cells are denser than platelets, so they will migrate to the area below platelets during this preparation phase. The platelet-rich plasma aliquot is centrifuged at a heavy spin, not the red cell portion. Because the white blood cells would not be present in this aliquot, leukocyte reduction is not needed. The plasma is removed from the platelet-rich plasma bag, which does not contain white blood cells. Because of this leukocyte reduction is not needed.

A patient's serum reacts with all reagent red cell samples. The autocontrol is negative. An alloantibody to a high incidence antigen is suspected. Which of the following would most likely be a compatible donor? - Patient's parents - Patient's siblings - Patient's children - Autologous donation

- Autologous donation Patients with an alloantibody to a high incidence antigen are missing the corresponding high incidence antigen on their red cells. In most cases, this results from inheritance of the same rare blood group gene from both parents. Finding compatible blood for patients with an antibody to a high incidence antigen may be a challenge. Autologous donations should be encouraged. Other sources of antigen negative blood may include family members and the rare donor registry. Siblings are much more likely to have inherited two doses of this same gene than the random donor population. Parents and children of the patient will more likely only have a single dose of the rare blood group gene in question and are less likely to be a source of compatible blood.

Which of the following group B antigens is generally associated with a mixed field reaction? - B - B3 - Bm - Bx

- B3 B3 is characterized by a weaker than usual reaction with anti-B and by a mixed field reaction with the same reagent. B is characterized by a strong reaction with anti-B. Bm and Bx are characterized by a weaker than usual reaction with anti-B but no mixed field reactions.

What is the MOST common infective agent to be transmitted through blood transfusion that results in morbidity and mortality? - Bacteria - Human immunodeficiency virus (HIV) - Hepatitis A virus (HAV) - Malarial parasites

- Bacteria The most common infectious agent to be transmitted through blood transfusion is bacteria. The estimated risk of contamination of blood components with bacteria is 1 in 5,000 platelet units and 1 in 30,000 red blood cell (RBC) units. For this reason, the inspections of RBC units that are done upon receipt of blood from a supplier, immediately before use, and at defined intervals must include a check for abnormal appearance. Comparison of bag and segment color should be performed for RBC units to aid in detection of bacterially-contaminated units.Storing RBCs above 6oC may promote the growth of bacteria. Platelets that are stored at 20-24oC are a particular concern. It is a requirement that platelet components be tested to detect the presence of bacteria. The risk of transmission of HIV through blood transfusion is 1 in 2 million in the United States. The statistics from Canada and Europe show this risk to be about the same or less. HAV is normally transmitted through the feco-oral route, but rarely can be transmitted through blood. The FDA recommends that donors who have a history of malaria be deferred from donation for 3 years after becoming asymptomatic and for one year following return from an area where malaria is endemic. The initial interview of donors has made the transmission of malarial parasites through blood transfusion a rarity.

During routine inspection, a unit of unexpired blood was noticed to have a black color with numerous small clots. What is the likely cause for this observation? - The unit was frozen - Donor had DIC - Viral contamination - Bacterial contamination

- Bacterial contamination Bacterial contamination can manifest itself in several ways including: the presence of clots, darker purple-black color of blood unit, unit can appear cloudy, hemolysis may be present. A unit that was frozen inadvertently should be discarded and would be hemolyzed upon returning to normal storage temperature. A donor with DIC would not have been in adequate health to be an acceptable donor. Viral contamination of a unit would likely not demonstrate visible signs of compromise.

Glycine-HCL/EDTA treatment of red cells can destroy which of the following antigens, allowing for confirmation of a suspected antibody and detecting additional antibodies? - Kidd - Bg and Kell - Ss - Duffy

- Bg and Kell Glycine-HCL/EDTA treatment of red cells can destroy Bg and Kell system antigens. Glycine-HCL/EDTA treatment does NOT destroy Kidd, Ss, or Duffy system antigens.

Which of the following choices best describes the primary function of antibodies? - Protection of B-lymphocytes - Binds with antigen - Fixes complement - Stimulates the immune response

- Binds with antigen The primary function of an antibody is to bind with its specific antigen to facilitate clearance of that antigen. Antibodies are produced by B-lymphocytes as part of the humoral response, but they do not protect B-lymphocytes. The complement system may be activated through the formation of antigen-antibody complexes, but this is not the primary function of antibodies. Antigens stimulate an immune response; antibodies are produced when an immune response is initiated.

When a group O patient's serum is not compatible with donor O red blood cells and the auto control is negative, what is the MOST likely cause? - Warm autoantibodies - Cold autoantibodies - Bombay phenotype - A2 phenotype

- Bombay phenotype The Bombay phenotype occurs when two hh genes (or two inactive alleles of H or FUT1) are inherited at the H locus. These individuals cannot produce alpha-2-L-fucosyltransferase to produce H, A, or B antigens. Consequently, they produce anti-H, anti-A, and anti-B antibodies. Upon initial testing, Bombay red blood cells appear to be group O. However, their serum reacts with antibody screening cells and all normal group O cells due to the presence of anti-H.

Which is in the correct order from the lowest concentration of H antigen to the highest concentration of H antigen? - Bombay, A1B, A1, A2B, B, A2, O - A1, O, B, A2, Bombay, A1B, A2B - Bombay, O, A1B, A2, A1, B, A2B - A1B, A2B, A2, O, B, A1, Bombay

- Bombay, A1B, A1, A2B, B, A2, O The H antigen is an essential precursor to the ABO blood group antigens. Individuals with the rare Bombay phenotype (hh) do not express antigen H on their red blood cells; therefore, this type would contain the least amount of H antigen. Those which are type A1B would then have the second to least amount of H antigen since the precursor H antigens have been formed into A1 and B antigens instead. The remaining order of the H concentration from lowest to highest in the blood types given is: A1, A2B, B, A2, and O. O patients produce the most H antigen since they do not convert the H antigen into A or B antigens on their cell surface.

Which of the following would be a possible cause of a positive direct antiglobulin test (DAT)? - Transfusion reaction and warm autoimmune disease only - Warm autoimmune disease and clot tube stored at 4°C only - Clot tube stored at 4°C and transfusion reaction only - Clot tube stored at 4°C, transfusion reaction, and warm autoimmune disease.

- Clot tube stored at 4°C, transfusion reaction, and warm autoimmune disease. A positive DAT is associated with transfusion reactions, warm autoimmune disease, clot tube stored at 4oC, cold autoimmune disease, drug interactions, and hemolytic disease of the fetus and newborn.

Which of the following D variants has the best likelihood to receive D-positive RBCs without any adverse effects? - Del - Partial D - Partial weak D - C in Trans to RHD

- C in Trans to RHD Individuals with C in Trans to RHD possess complete D antigen structures. The allele that carries C is in trans (or opposite position) from the allele carrying RHD. As a result, the position of the C antigen in relationship to the D antigen interferes with the expression of the D antigen. This can be a weakened expression of D antigen; however, D antigen is still present. These patients can receive D-positive RBCs without the implication of an Rh-mediated transfusion reaction. In partial D and partial weak D individuals, they can produce Rh antibodies to the portion of the RhD gene that is missing. There is a risk for potential adverse effects to occur when these individuals are recipients of D-positive RBCs. Individuals with Del phenotype possess a low number of D antigen sites that can go undetected in routine serological testing. This testing discrepancy can lead to misclassification of Rh type for the recipient (i.e., classified RhD-negative but maybe RhD-positive). Molecular studies are needed to detect the mutant RHD gene responsible for altering the expression of the RhD protein.

Which cluster of differentiation (CD) is used for the quantification of hematopoietic progenitor cells (HPC) after an HPC-apheresis collection? - CD34 - CD4 - CD8 - CD2

- CD34 The correct answer is CD34. HPC's are CD34+ and after an HPC-apheresis collection, the number of CD34+ cells are quantified to ensure that there are sufficient cells for successful engraftment.CD4, CD8, and CD2 are all lymphocyte surface markers.

Which of the following genotypes is found with the highest frequency in the Caucasian population? - CDe/cDe - cDE/ce - cDE/cE - CDe/ce

- CDe/ce The genotype CDe/ce is found in 31% of the Caucasian population. The genotype CDe/cDe is found in 3% of the Caucasian population. The genotype cDE/ce is found in 10% of the Caucasian population. The genotype cDE/cE is found in less than 1% of the Caucasian population.

Persons who have received a dura mater transplant are not eligible to donate blood and are permanently deferred. This is due to an increased risk of which of the following? - HIV - Leishmaniasis - Chagas Disease - CJD or vCJD

- CJD or vCJD Persons who have received dura mater (brain lining) grafts are permanently deferred due to an increased risk of exposure to Creutzfeldt-Jakob (CJD) disease and variant CJD (vCJD).HIV is not correct. The full-length donor history questionnaire is designed to identify donors who are at increased risk for HIV. Leishmaniasis is caused by a parasite that is transmitted by the sand fly. They are endemic in tropical and subtropical areas of the world. Chagas disease is caused by the parasite Trypanosoma cruzi. It is endemic in parts of Central America, South America, and Mexico.

Which of the following consequences of severe hemolytic disease of the fetus and newborn (HDFN) is most associated with neonatal death before or shortly after birth? - Enlarged liver - Enlarged spleen - Cardiac failure - Hyperbilirubinemia

- Cardiac failure While the other consequences of HDFN can be severe in and of themselves, cardiac failure is the greatest threat to the fetus. In HDFN, the antibodies bind to the fetal antigens, which ends in red cell destruction by macrophages in the fetal liver and spleen. As red cell destruction continues, the fetus becomes increasingly anemic. The fetal liver and spleen enlarge as erythropoiesis increases to compensate for the red cell destruction. Hemoglobin is liberated from the damaged cells, metabolized to indirect bilirubin and is transported across the placenta where it is conjugated by the maternal liver and excreted. As the red cell destruction continues, cardiac failure resulting from uncompensated anemia will occur.

Which of the procedures listed below will increase the platelet concentration in the preparation of platelets? - Centrifuge the blood at a low speed, remove the plasma and spin the plasma again at a low speed. - Centrifuge the blood at a low speed, remove the plasma and spin the plasma again at a high speed. - Centrifuge the blood at a high speed, remove the plasma and spin the plasma again at a high speed. - Decrease the duration of rotation of the initial spin.

- Centrifuge the blood at a low speed, remove the plasma and spin the plasma again at a high speed. The preparation of platelets is a two-step process. The whole blood unit should be centrifuged at a low speed on the first spin. The platelets will then remain in the plasma portion of the bag (platelet-rich plasma). The platelet-rich plasma is then centrifuged again at a higher speed, forcing the platelets to the bottom of the container. By taking part of the plasma off the second spin, the platelets are at a higher concentration per unit volume. Centrifuging at low speed for both spins will not allow the platelets to concentrate in the sediment of the second spin. Centrifuging at high speed for both spins will actually make the first plasma platelet-poor. Decreasing the duration of the initial spin will increase the red blood cell contamination and decrease the overall platelet count.

What is the FIRST thing blood bank staff should do when investigating a transfusion reaction? - Perform an IAT on the post-transfusion sample and DAT on the patient sample. - Check for clerical errors in all steps of the pre- and post processes. - Repeat ABO and Rh typing of the patient and donor unit. - Perform an antibody screen on pre- and post-transfusion samples.

- Check for clerical errors in all steps of the pre- and post processes. The blood bank technologists must always check for clerical errors in all steps of the pre- and post-transfusion processes immediately after a transfusion reaction is reported. Check the information on the post-transfusion sample, transfusion documentation, and blood unit bag to ensure it all matches. Post-transfusion (or secondary) testing includes all of the following: Check for hemolysis on pre-transfusion sample. If hemolysis is not present, then repeat ABO, antibody screen, and crossmatch testing on the post-transfusion sample. Any positive results on repeat testing of the post-transfusion sample requires repeat testing on the pre-transfusion sample also. DAT on pre- and post-transfusion samples. Repeat ABO/Rh testing on the pre-transfusion sample.

What is the MOST common cause of acute hemolytic transfusion reactions? - Testing errors - Clerical errors - Donor IgG immune antibodies - Blood administration errors

- Clerical errors The correct answer is clerical errors. Improper patient identification at the time of sample collection or transfusion is the most common cause of an acute immune hemolytic transfusion reaction. Testing errors can cause acute hemolytic transfusion reactions, but they are not the most common cause. Donor IgG antibodies should not be transmitted to a patient, as patients with a positive antibody screen are generally deferred. Blood administration errors can cause acute hemolytic transfusion reactions, but they are not the most common cause.

Fresh frozen plasma should be used for which of the following? - Platelet replacement - Coagulation deficiencies - Volume replacement - Albumin replacement

- Coagulation deficiencies FFP, or fresh frozen plasma, should be used to treat coagulation deficiencies, although the levels of factors V and VIII are usually decreased in FFP units. FFP is not used for platelet replacement as there are virtually no platelets in FFP units. FFP should never be used as a volume expander unless traumatic bleeding is taking place. Finally, FFP is not used to replace albumin in recipients.

In the ABO blood group system, the A antigen is inherited in what relation to the B antigen? - Codominant - Dominant - Recessive - Amorphic

- Codominant In the ABO blood group system, the A and B antigens are inherited in a codominant fashion, meaning that a person who inherits the A antigen from one parent and the B antigen from the other will demonstrate both the A and B antigens. Both the A and B antigens are inherited in a dominant fashion over the O antigen. If a person inherits an A or B antigen from one parent and an O antigen from the other, the A or B antigen will be demonstrated. The O antigen is recessive to the A and B antigens. A person must inherit the O antigen in the homozygous form, OO, in order to demonstrate it phenotypically. The O antigen is amorphic, meaning that it does not produce any demonstrable antigen.

Which of the following methods are a non-invasive way to reliably predict anemia in the fetus? - Antibody titer - Color Doppler middle cerebral artery peak systolic velocity (MCA-PSV) - Cordocentesis - Aminocentesis

- Color Doppler middle cerebral artery peak systolic velocity (MCA-PSV) Color Doppler middle cerebral artery peak systolic velocity (MCA-PSV) is a non-invasive technique to predict anemia in the fetus reliably. Color Doppler ultrasound is used to indicate the direction of blood flow and locate the middle cerebral artery of the fetus (this artery is used due to ease of locating). The velocity of blood flow is measure as an indicator of blood viscosity. The reduced blood viscosity (due to low hematocrit) results in faster velocity. The peak systolic velocity can be plotted to determine if or when cordocentesis needs to be performed. A maternal antibody titer is used to determine if clinical fetal monitoring is warranted. However, it is an unreliable indicator of the severity of HDFN (titer can be low, and HDFN can be severe), and it does not predict anemia of the fetus. Cordocentesis is used to obtain a fetal sample from the umbilical vein. It is a reliable method to monitor anemia, but it is invasive. Amniocentesis is performed to obtain amniotic fluid, and it is a reliable method to monitor anemia, but it is also an invasive technique.

Which one of the following tests BEST correlates with the severity of hemolytic disease of the fetus and newborn (HDFN)? - Color Doppler ultrasonography - An antibody screen of mother's blood - Amniotic fluid bilirubin - Antibody titer of mother's blood

- Color Doppler ultrasonography Fetal anemia caused by hemolysis of red cells during pregnancy can be detected by color Doppler ultrasonography. This can determine the severity of fetal anemia. Before the development of this technology, the severity of HDFN was measured by amniocentesis. An antibody screen using separate screening cells to detect clinically significant IgG alloantibodies can be performed. If the antibody screen is positive, an identification panel should be performed. Laboratory testing for the corresponding paternal red blood cell antigens can predict the future risk of HDFN. Amniotic fluid bilirubin is increased in association with the severity of hemolytic diseases of the newborn. As red blood cells lyse during these conditions, bilirubin builds up as a byproduct of red cell destruction. As more red blood cells are destroyed in the baby, the bilirubin level will become more increased. However, this uses a graph to estimate the severity of the HDFN. Once the critical titer for the given antibody is met, assessments for the possibility of fetal anemia must be undertaken using amniocentesis or middle cerebral artery Doppler ultrasound.

Which procedure used to obtain a fetal blood sample to monitor severity of hemolytic disease of the fetus and newborn (HDFN) can also be used to deliver intrauterine transfusions? - Amniocentesis - Cordocentesis - Doppler sonography - Exchange transfusion via maternal circulation

- Cordocentesis While performing a cordocentesis, a spinal needle is inserted into the umbilical vein, and a sample of fetal blood is obtained. The fetal blood sample can then be tested for hemoglobin, hematocrit, bilirubin, blood type, direct antiglobulin test, and antigen phenotype and genotype. Intrauterine transfusion is performed by accessing the fetal umbilical vein (cordocentesis) and injecting donor red blood cells directly into the vein.

A person who lived in the United Kingdom between the years of 1980 and 1996 for 3 or more months is indefinitely deferred from donating blood or blood products based on an increased risk of which of the following? - Malaria - Leishmaniasis - Creutzfeldt-Jakob disease (CJD) and/or variant Creutzfeldt-Jakob disease (vCJD) - Chagas disease

- Creutzfeldt-Jakob disease (CJD) and/or variant Creutzfeldt-Jakob disease (vCJD) The correct answer is CJD and/or vCJD. If a potential blood donor spent more than 3 months in the United Kingdom between 1980 and 1996, or 5 or more years in France from 1980 to the present, they are indefinitely deferred due to an increased risk of CJD and/or vCJD. If they have ever been diagnosed with CJD or vCJD, they are permanently deferred. Persons with malaria or who have been infected with malaria are deferred for a period of 3 years after they are asymptomatic. The United Kingdom (UK) is not a malaria-endemic area and traveling to the UK in and of itself, would not be cause for deferral based on a potential malaria infection. Traveling to an area that is endemic for Leishmaniasis may be cause for a 12-month deferral from the time you left the area. The UK is not an Leishmaniasis endemic area. It is endemic in tropical and subtropical areas of the Middle East, Mediterranean, Africa, Central and South America, and Asia. Chagas disease is endemic in parts of Central and South America and Mexico. The UK is not an endemic area of Chagas disease. All potential donors are tested one time for Trypanosoma cruzi, the causative agent of Chagas disease. If the potential donor tests nonreactive for Chagas disease, the donor doesn't need to be retested. The rational for this is that most persons with Chagas disease have a chronic infection that was acquired while in a endemic area.

Which of the following antigens is classified as a Major Histocompatibility Complex Class II antigen (MHCII)? - HLA-A - HLA-B - HLA-C - HLA-DR

- HLA-DR HLA-DR is a class II MHC. HLA-DP and HLA-DQ are the other class II MHC antigens, found on antigen presenting cells. HLA-A, HLA-B, and HLA-C are all class I MHC, found on the surface of platelets, leukocytes, and most nucleated cells.

Which of the following blood components contains the most factor VIII concentration relative to the unit volume? - Whole Blood - Cryoprecipitated AHF - Fresh Frozen Plasma - Platelet Concentrate

- Cryoprecipitated AHF Cryoprecipitated AHF is the cold-insoluble portion of plasma that remains after Fresh Frozen Plasma has been thawed at 1 - 6oC. It is rich in von Willebrand factor, fibrinogen, factor VIII, fibronectin, and factor XII. Since many components are made from whole blood, factor VIII is present in this component, but concentration would be low relative to unit volume. Fresh Frozen Plasma contains all the coagulation factors, >but the concentration of factor VIII would be low relative to unit volume. While a small amount of plasma is present in platelets, the amount of factor VIII present would be negligible.

Which is the best component to treat a patient with fibrinogen deficiency? - Red Blood Cells - Platelet Concentrate - Fresh Whole Blood - Cryoprecipitated AHF

- Cryoprecipitated AHF Cryoprecipitated AHF is the only product that contains a concentrated amount of fibrinogen. Cryoprecipitate contains a minimum of 150 mg of fibrinogen in each unit. It is primarily used for fibrinogen replacement in patients diagnosed with a congenital fibrinogen deficiency. Red blood cells, platelet concentrate, and fresh whole blood do not contain enough concentrated fibrinogen to be adequate in treating patients with fibrinogen deficiency.

A 28 year old female patient is experiencing disseminated intravascular coagulation (DIC) following the delivery of her newborn. Her Complete Blood Count (CBC) results are normal. What would be the best blood product for this patient to receive? - Apheresis platelets - Leukocyte-reduced packed red blood cells - Cryoprecipitated antihemophilic factor - Fresh frozen plasma

- Cryoprecipitated antihemophilic factor Cryoprecipitated antihemophilic factor, often called cryo or cryo AHF, contains concentrated coagulation factors. Since the coagulation factors are concentrated in this blood product, its administration does not also add additional cells or volume, which minimizes the risk of transfusion-related conditions such as transfusion-associated circulatory overload (TACO). Platelets, whether pooled or apheresis, should only be administered in patients with a decreased platelet count or function. The patient had normal values on the complete blood count, which indicates that the platelet count was normal. There is no indicated need for the patient to receive red blood cells since the complete blood count results were normal, specifically the red blood cell, hemoglobin, hematocrit, and red blood cell indices. Administering red blood cells to patients with normal red blood cell values can lead to transfusion-associated circulatory overload or TACO. Though fresh frozen plasma contains coagulation factors, it is not the best option. The concentration of coagulation factors in fresh frozen plasma is not as high as in cryoprecipitated AHF, and the plasma itself could cause adverse reactions to the patient due to the fluid volume.

Which of the following is used as a source for irradiation of blood products? - Cs137 - I131 - C14 - P51

- Cs137 Irradiation is performed using cesium-137 or cobalt-60. To confirm a product was irradiated, a radiochromic film label is affixed to the component before it is placed into the metal canister of the irradiator. Darkening of the film confirms irradiation requirements.

A low-incidence antigen is one that occurs in less than 10% of the population. Which of the following is a low-incidence antigen? - D - c (little c) - Fyb - Cw

- Cw Of those listed, Cw is the only low-incidence antigen. - The D antigen occurs on approximately 85% of the population. Therefore, it is not a low-incidence antigen. - The c (little c) antigen occurs on approximately 80% of the white population and approximately 97% of the black population. It is not a low-incidence antigen. - The Fyb (Duffy b) antigen occurs in approximately 83% of the white population and approximately 23% of the black population. It is not a low-incidence antigen.

Leukocyte-reduced blood products may be administered to reduce the risk of febrile reactions and what disease or condition? - Graft-vs-host disease - Cytomegalovirus - Malaria - Bacteremia

- Cytomegalovirus Cytomegalovirus (CMV) is present in the cytoplasm of white blood cells. Reducing the number of white blood cells that are present in a donated red cell unit reduces the viral load of cytomegalovirus. Leukoreduction is not successful at preventing transfusion-associated graft-vs-host disease (TA-GVHD). However, this is an uncommon route for graft-vs-host disease as it is typically transmitted through allogenic bone marrow transplantation. Malaria is found extracellularly or in red blood cells, so leukoreduction would not affect any Plasmodium species that may be present in donated red blood cells. Bacteremia exists extracellularly, so leukoreduction would not affect any bacteria present in donated red cells. The filter used in leukocyte reduction cannot filter bacteria.

A D-positive mother with a D-negative fetus eliminates the possibility of HDFN due to the: - D antigen - ABO antigen system - Lewis antigen system - Rh antigen system

- D antigen The correct answer is the D antigen. In order to have HDFN due to the D antigen, the mother must be D-negative with a D-positive fetus. More information would be necessary to determine the impact of ABO antigens on HDFN. Lewis antigens do not cause HDFN. Other Rh antigens still have the capability of causing HDFN.

Which of the following patients is eligible for RhIG? - D-positive woman, 28 weeks gestation, no unexpected antibodies - D-negative woman, 28 weeks gestation, no unexpected antibodies - D-negative woman, 28 weeks gestation, immune anti-D present in serum - D-positive woman, 28 weeks gestation, anti-K present in serum

- D-negative woman, 28 weeks gestation, no unexpected antibodies A D-negative woman at 28 weeks gestation with no unexpected antibodies present in her serum is eligible for RhIG administration to help protect her from making immune anti-D if she is carrying a D-positive fetus. D-positive women cannot make immune anti-D and are not eligible for RhIG regardless of any other unexpected antibodies present. RhIG only prevents immunization to the D antigen. D-negative women who have already made immune anti-D would not be eligible for RhIG.

An antibody to which platelet antigen is most commonly encountered in blood bank? - HPA-1a - HPA-2a - HPA-3a - HPA-4a

- HPA-1a Currently, only 33 human platelet antigens have been identified. Antibodies to platelet antigens are not commonly found since there is low variability among the antigens. However, antibodies to the HPA-1a antigens are the most commonly found in blood bank tests. HPA-2a, HPA-3a, and HPA-4a are all platelet antigens, but patients do not typically produce antibodies against these antigens.

Post-natal RhIg is indicated for which of the following mother and neonate pairs? - D-negative neonate born to D-positive mother - D-negative neonate born to D-negative mother - D-positive neonate born to D-negative mother - D-positive neonate born to D-positive mother

- D-positive neonate born to D-negative mother The red cell antigens from a D-positive neonate born to a D-negative mother could stimulate the mother's immune system to synthesize anti-D. Administration of RhIg can be used to prevent this from happening. A D-negative neonate born to a D-positive mother is not a cause for concern as the mother has the D antigen and will not produce anti-D. A D-negative neonate born to a D-negative mother will not stimulate the mother's immune system to produce anti-D since the neonate does not have the D antigen. A D-positive neonate born to a D-positive mother will not stimulate the mother's immune system since the mother already has the D antigen and will not produce anti-D.

Storage lesion, or the biochemical changes in red blood cells during storage, will result in: - Decreased hemoglobin - Increased plasma sodium - Decreased plasma potassium - Decreased plasma pH

- Decreased plasma pH Storage lesion will cause a decrease in plasma pH levels as lactic acid levels increase during storage. The free hemoglobin levels will increase as red blood cells lyse. The plasma sodium levels will decrease as a dilutional effect of hemolysis. The plasma potassium levels will increase due to hemolysis within the unit.

What is the fundamental purpose of the full, pre-transfusion crossmatch? - Detect antibodies in recipient serum/plasma that react with donor red blood cells. - Discover HLA antibodies in graft-versus-host situations. - Verify that the donor and recipient are the same blood type. - Prevent hemolytic destruction of the recipient red blood cells.

- Detect antibodies in recipient serum/plasma that react with donor red blood cells. The purpose of performing a crossmatch is to determine whether or not donor RBCs are compatible for transfusion by testing the donors' RBCs against the recipient serum (or plasma) which may contain alloantibodies that can potentially react with these donor RBCs. The crossmatch is a final check of ABO compatibility between both donor and the recipient. The donor and recipient may not have the same blood type based on product selection and inventory.

What action should be taken if a large clot is noticed in a red blood cell unit while the product is being prepared for release to the patient? - Issue the product as you normally would but with a filter. - Issue the product, but note the presence of the clot in the computer records. - Filter the product prior to issue and record the process. - Do not issue the product.

- Do not issue the product. This integrity of this product is compromised. The unit cannot be used even with a filter and should be quarantined and returned to the blood supplier for investigation.

Which is NOT a requirement for information on the donor tag once the appropriate compatibility testing has been completed and the unit or units are suitable for transfusion? - Patient's full name and identification number - Name of the product and donor number - ABO & D phenotype of the unit - Doctor's name and patient room number

- Doctor's name and patient room number The doctor's name and the patient's room number are not required to be on the tag attached to the donor unit. When the appropriate compatibility testing has been completed, and the unit or units are suitable for transfusion, a tag is produced and attached to each donor unit. The donor unit tag must clearly state the patient's full name and identification number, name of the product, donor number, expiration date, ABO and D phenotype of the unit, interpretation of the crossmatching test (if performed), and identity of the person doing the testing or selection of the unit.

Which of the following is the most common reagent source for anti-A1? - Group A1 plasma - Dolichos biflorous seed extracts (lectins) - Bandeiraea simplicifolia seed extracts (lectins) - Ulex europaeus seed extracts (lectins)

- Dolichos biflorous seed extracts (lectins) Lectins are seed extracts that can be utilized in the laboratory to agglutinate red blood cells. The lectin from the seeds of Dolichos biflorus is commonly used as a source of anti-A1. The use of this lectin allows the blood bank laboratory to differentiate A1 individuals from A2 individuals. This is important because some A2 individuals can make anti-A1, causing an ABO discrepancy when doing reverse grouping (forward looks like group A, but reverse looks like group O). The use of Dolichos biflorus assists the blood banking laboratory in resolving this discrepancy so that the patient's ABO grouping can be determined. If the patient's red blood cells do not agglutinate with the lectin the patient may in fact be group A2 making an anti-A1. Group A1 individuals do not make anti-A1. See extracts from Bandeiraea simplicifolia serve as a source of Anti-B Seed extracts from Ulex europaeus serve as a source of anti-H.

What is considered the definition of allogeneic blood? - Donated by the donor for self-use - Donated by a donor for a recipient other than the donor to use - Blood salvaged during surgery - Blood collected through normovolemic hemodilution

- Donated by a donor for a recipient other than the donor to use A voluntary donation of blood for use by the general patient population is called allogeneic. Allogeneic blood is blood that is transfused to someone other than the blood donor. All the other choices are considered sources of autologous blood. Blood that is transfused to the person who donated the blood is referred to as autologous blood. If blood is salvaged during surgery, recycled, and transfused back to the donor during surgery, the term that is applied is perioperative blood collection. During normovolemic hemodilution, blood is collected at the beginning of surgery, and the volume is restored with crystalloid or colloid solutions. The blood will be transfused back to the patient during or at the end of the surgery.

For which of these reasons would a molecular method not be used? - Determine blood type when the DAT is positive - Complex Rh genotypes (weak D expression) - Donor antibody screening - Type fetal blood

- Donor antibody screening Applications of molecular testing in blood bank include donor antigen screening not donor antibody screening. Other applications include determining blood type when the DAT is positive, identifying complex Rh genotypes, and typing fetal blood.

All of the following cellular antigens are important to an immunohematologist EXCEPT: - Blood group antigens - Histocompatibility antigens - Haptens - Autoantigens

- Haptens The correct answer is haptens. Haptens are immunogens that have a molecular weight less than 10,000 daltons and usually do not elicit an immune response on their own, thus they are not considered clinically significant. Blood group antigens are important in compatibility testing for red blood cell transfusions. Histocompatibility antigens are important for compatibility testing involving nucleated cells. Autoantigens are important for all compatibility testing.

Which of the prospective donors below would be an acceptable blood donor? - Donor number 1: Blood pressure: 90/55 Pulse: 105 Temperature: 36.4ºC (97.6 ºF) - Donor number 2: Blood pressure: 200/90 Pulse: 72 Temperature: 37ºC (98.6 ºF) - Donor number 3: Blood pressure: 110/72 Pulse:66 Temperature: 37.2ºC (99.0 ºF) - Donor number 4: Blood pressure: 100/70 Pulse: 98 Temperature: 38.3 (101.0 ºF)

- Donor number 3: Blood pressure: 110/72 Pulse:66 Temperature: 37.2ºC (99.0 ºF) The correct answer is donor number 3. Systolic blood pressure must be less than or equal to 180; diastolic blood pressure must be less than or equal to 100; pulse must be within 50-100 beats per minute; temperature must be less than or equal to 37.5oC (99.5oF). Donor number 1 has a pulse above 100. Donor number 2 has a systolic blood pressure above 180. Donor number 4 has a temperature above 37.5oC (99.5oF).

The major crossmatch is performed using: - Donor's serum and recipient's red cells - Donor's serum and recipient's serum or plasma - Donor's red cells and recipient's serum or plasma - Donor's red cells and recipient's red cells

- Donor's red cells and recipient's serum or plasma Crossmatch procedures involve recipient serum or plasma, which contains all potential red cell antibodies, tested with donor red blood cells, which contain all antigens, to ensure compatibility of the cells prior to transfusion in an effort to prevent a potential transfusion reaction due to ABO incompatibility or donor mislabeling. Performing a crossmatch with donor serum and recipient red cells will not prevent a potential transfusion as it cannot predict a transfusion reaction that may occur in the recipient. Performing a crossmatch with donor and recipient serum will only combine all potential antibodies. Without the ability to combine the potential serum antibodies with red cell antigens, it is impossible to screen for a potential transfusion reaction. Performing a crossmatch with donor and recipient red cells will only combine red cell antigens. Without the ability to combine the serum antibodies with red cell antigens, it is impossible to screen for a potential transfusion reaction.

An error was made in a handwritten blood bank record. Which of the following methods is acceptable for correcting the error to remain in compliance with current good manufacturing practices requirements? - Use white correction fluid to completely cover the error. - Draw a single line through the error so that it can still be read and add your initials next to it. - Erase the error as much as possible and write the correction on top of the obliterated result. - Use black marker to black-out the incorrect text and write the correction on top of the obliterated text.

- Draw a single line through the error so that it can still be read and add your initials next to it. The correct answer is "Draw a single line through the error so that it can still be read and add your initials next to it". 21 CFR 600.12 requires records to be legible and indelible. Records cannot be covered up with correction fluid or tape, or be obliterated. Corrections to a record should be made in a manner that allows the error to still be read so that it can be reviewed. The correction should also include the date the correction was made and the person who made the correction.

A patient experiences a mild allergic reaction to a transfusion, including urticaria, erythema (skin redness), and itching. What is the most likely source of the allergen? - IgA on mast cells - Drugs or food consumed by the blood donor - Insoluble allergens - Donor red blood cells

- Drugs or food consumed by the blood donor Allergen substances may be drugs or food consumed by the blood donor. The blood recipient forms antibodies to these allergens bound to IgE on mast cells and causes the release of histamines. Mild allergic reactions result from a patient's hypersensitivity to soluble allergens in the plasma of the donor unit. Reactions against donor red blood cells would cause acute or delayed hemolytic transfusion reactions.

All of the following RBC antigens are high-frequency EXCEPT: - k (little k) - E (big E) - Lub - Kpb

- E (big E) Of the RBC antigens listed, only E is NOT a high-frequency antigen. A high-incidence antigen occurs in 98% or more of the population. E occurs in 29% of the white population and 22% of the black population. Little k (k), Lub, and Kpb all occur in approximately 99% or more of the population.

At what frequency should quality control testing be performed on each lot of anti-human globulin to be in compliance with the FDA's current good manufacturing practices requirements? - At the beginning of each work shift - Each day of use - Only at the time of receipt - By each new user

- Each day of use The correct answer is 'each day of use.' 21 CFR 606.65 requires that a sample from the lot in use be tested on each day of use. More frequent testing may be required by the facility, such as at the beginning of each work shift or by each new user, but the FDA minimum requirement is each day of use. While testing may be required when a reagent is received, it does not substitute for testing on the day of use. If the reactions with known specimens are used for quality control evaluation, both a positive and negative specimen must be used.

In which of the following cases should Rh Immune Globulin (RhIG) be given? - Ectopic pregnancy - Rh positive mother carrying an Rh negative fetus - Rh postive mother carrying an Rh positive fetus - Rh negative mother with anti-D formed from previous pregnancy

- Ectopic pregnancy Rh Immune Globulin (RhIG) is used to prevent active immunization to the D antigen in Rh negative females carrying an Rh positive fetus. Fetal cells can enter maternal circulation during pregnancy and during delivery. Administration of RhIG at 28 weeks (antenatal) and within 72 hours of delivery helps prevent the mother from being sensitized to the D antigen. When an ectopic pregnancy occurs, the blood type of the fetus can usually not be determined but it is possible for fetal blood to enter maternal circulation. Therefore, RhIG is given to protect the mother from forming an anti-D which could pose a risk to future pregnancies. This is also done in cases of abortions and stillbirths when the blood type of the fetus cannot be determined. A woman is only a candidate when she is Rh negative since Rh negative women are the population at risk of forming an anti-D. Additionally, the mother should not already have a circulating anti-D since the goal is to prevent sensitization. Anti-D in circulation would mean that sensitization has already occurred.

Persons with hemophilia A or hemophilia B that demonstrate inhibitors should be given which of the following products? - Factor VIII concentrates - Factor IX concentrates - Factor VIIa - Factor X

- Factor VIIa Factor VIIa is used for persons with hemophilia A or hemophilia B that demonstrate inhibitors. Factor VIII is used for persons with hemophilia A with no inhibitors. Factor IX is used for persons with hemophilia B with no inhibitors. Factor X could be used for persons demonstrating Factor X deficiency.

Hemolytic anemias are diagnosed by clinical findings and laboratory test results. All of the following are lab values that are relied on to help diagnose hemolytic anemia EXCEPT? - Hemoglobin and/or hematocrit - Retic count and RBC morphology - Bilirubin and haptoglobin - Fibrinogen and C-reactive protein

- Fibrinogen and C-reactive protein The correct answer is fibrinogen and C-reactive protein. While both of these analytes are acute phase reactants (proteins) and may be increased during hemolysis, they are NOT specifically related to hemolysis or hemolytic anemia. In hemolytic anemias, the hemoglobin and hematocrit would be decreased and would be useful in the diagnosis of hemolytic anemia. The retic count and RBC morphology would both be helpful in the assessment and diagnosis of hemolytic anemia. The retic count could indicate the bone marrows response and the RBC morphology may indicate whether the hemolysis is intravascular or extravascular. Both bilirubin and haptoglobin aid in the diagnosis and assessment of hemolytic anemia. Bilirubin levels would be increased and haptoglobin values would be decreased, particularly in intravascular hemolysis.

The Rh nomenclature which uses the letters DCE is found in which of the following genetic models? - Wiener - Shorthand - Fisher -Race - Rosenfield

- Fisher -Race Numerous genetic models have been proposed to describe the inheritance of the antigens within the Rh blood group system. Fisher and Race first proposed the existence of the three closely linked genes, and used the DCE terminology to describe their theory. They postulated that each gene produced an antigen expressed on the RBC surface. Wiener postulated that there was one gene present which produced an agglutinogen containing at least three antigens. Rh-Hr terminology is used to describe the Wiener theory. Shorthand refers to terminology that is used to describe Rh antigens inherited on one chromosome or haplotype. The use of shorthand allows clinical laboratory scientists to verbally communicate Rh antigens easier. An example is R1 which is used to represent the presence of DCe on one chromosome. Rosenfield is an alphanumeric terminology that assigns a number to antigens within different blood group systems. It was initiated due to the difficultly in assigning names to new antigens. In the Rh system Rh1 is D, Rh2 is C, Rh3 is E, Rh4 is c and Rh5 is e.

Which of these methods measures fetal hemoglobin or D positive red cells or both to evaluate fetomaternal hemorrhage? - Rosette test - Kleihauer-Betke test - Flow cytometry - AHG testing

- Flow cytometry Flow cytometry measures fetal hemoglobin or D positive red cells or both. In patients with a positive rosette test (a screening for fetomaternal hemorrhage), a quantitative test such as Kleihauer-Betke test or flow cytometry is performed to calculate the dose of Rh immune globulin. The Kleihauer-Betke acid elution is based on the fact that fetal hemoglobin is resistant to acid elution and adult hemoglobin is not resistant to it. Examples of polyclonal antiserum produced for blood bank testing are known as antihuman globulin (AHG) reagents. These products contain multiple antibody specificities.

Which of the following is the MOST likely discrepancy seen when a person demonstrates an "acquired B-antigen" phenomenon? - Forward typing appears to be B, but reverse group type is O. - Forward typing appears to be AB, but reverse group type is A. - Forward typing appears to be AB, but reverse group type is B. - Forward typing appears to be B, but reverse group type is AB.

- Forward typing appears to be AB, but reverse group type is A. The correct answer is forward typing appears to be AB, but reverse group type is A. Acquired B is seen only in a subpopulation of group A1 individuals. The individuals that demonstrate acquired B antigen still possess anti-B, but the anti-B does not react with the acquired B antigen; consequently, the auto control is negative. Since this phenomenon can only be seen in group A individuals and only affects the forward group, when a person exhibits the acquired B antigen, they must have an AB forward type and an A reverse type.

Which blood component is the most commonly used component for the replacement of multiple coagulation factor deficiencies in bleeding patients? - Fresh Frozen Plasma - Red Blood Cells - Cryoprecipitate - Whole Blood

- Fresh Frozen Plasma Fresh Frozen Plasma (FFP) is indicated for bleeding patients with multiple coagulation factor deficiencies due to inadequate production, as in liver disease; excessive consumption, as in disseminated intravascular coagulation (DIC); or dilution, as in massive transfusion, generally defined as the replacement of one or more blood volumes in a period of 24 hours or less. FFP is also indicated for non-bleeding patients with multiple deficiencies who are undergoing invasive procedures. FFP is also used to reverse warfarin therapy in bleeding patients and for patients with congenital factor deficiencies for which no concentrates are available. Cryoprecipitate contains concentrated sources of fibrinogen and Factor VIII but would not be indicated for multiple factor deficiencies. Red blood cells and whole blood do not contain coagulation factors.

Which of the following genotypes are known to be resistant to P. vivax (malaria) merozoites? - Fy(a+b+) - Fy(a-b-) - Jk(a-b-) - Jk(a+b+)

- Fy(a-b-) The correct answer is Fy(a-b-). In the mid-70s, it was observed that Duffy (Fy) (a-b-) RBCs resist infection by Plasmodium knowlesi and Plasmodium vivax. This provides an explanation for the high frequency of Fy(a-b-) persons originating from West Africa. All of the other genotypes (Fy(a+b+), Jk(a-b-), and Jk(a+b+)) are not known to cause this type of resistance.

Which of the following blood group antigens are most susceptible to destruction by the action of enzymes? - D - Jka - Lea - Fya

- Fya Duffy, or Fya and Fyb antigens, are most sensitive to enzyme treatment since they will be destroyed during this process. Enzyme panels can be helpful when multiple antibodies, including Duffy, are present in a patient sample. With the Duffy antigens destroyed, the panel can be performed to identify the remaining antibodies present. Other antigens that are sensitive to enzyme treatment include those of the MNS system and Xga. D, Jka, and Lea are enhanced by enzymes (Rh, Kidd, Lewis, P1, I, and ABO).

When testing for the quality of platelet concentrates, all of the following must be included EXCEPT? - pH - Platelet count - Bacterial detection - Gas production

- Gas production Gas production is the correct answer. While gas production may be used in one of the FDA approved methods to detect bacterial contamination, gas production, in and of itself, is not one of the mandatory quality testing methods. pH is incorrect, as it is one of the required items for testing platelet concentrate quality. The pH must be at 6.2 or greater. A platelet count is incorrect, as it is one of the required items for testing quality of a unit of platelets. Bacterial detection is incorrect, as it is one of the newer standards for testing the quality of platelet concentrates.

Many red blood cell (RBC) processes, such as binding, transporting, and releasing oxygen, do NOT require energy. Energy however, is required for cellular viability. How does the RBC obtain most of it's energy? - Glycolytic pathways - Hexose-monophosphate shunt - Rapoport-Luebering pathway - Methemoglobin reductase pathway

- Glycolytic pathways Most of the energy needed for RBC viability is obtained through the glycolytic pathway. About 90 to 95% of the cells' glucose is metabolized in this pathway, which in turn produces ATP. One glucose molecule produces a net gain of 2 moles of ATP via this pathway. The main function of the hexose-monophosphate shunt is to provide NADPH and glutathione to reduce oxidants, essentially minimizing the amount of oxyhemoglobin that would convert to methemoglobin. The Rapoport-Luebbering pathway controls the amount of 2,3-BPG that gets produced. The methemoglobin reductase pathway functions to protect hemoglobin from oxidation by NADH and methemoglobin reductase.

The parents' blood types are AB and O. What could be the only possible blood type(s) of their children? - Group A only - Group B only - Group O only - Group A or B only

- Group A or B only If the parents' have AB and O blood types, then the child could have only AO or BO inheritance patterns resulting in a group A or group B baby. A B O AO BO O AO BO

Which of the following types of whole blood is the only one to be transfused to a type AB patient? - Group O - Group A - Group B - Group AB

- Group AB The recommended whole blood to be given to an AB patient is from an AB donor. Group O whole blood contains both anti-A and anti-B, which could severely react with the recipient's RBCs. Group A whole blood has anti-B, and group B whole blood has anti-A, which react with the B and A antigens on the recipient's RBCs. Group AB individuals can receive all blood groups if the units are given as packed red blood cells, not as whole blood.

What blood group are the RBC screening cells that are used for antibody screens? - Group O - Group A - Group B - Group AB

- Group O Antibody screening cells are group O reagent red cells that are used to screen for blood group antibodies other than the ABO antibodies. The 2-cell screening cells are O positive. The 3-cell screening cells have one as an O negative. Group A blood cells could not be used for looking for unusual antibodies since they would react with people who have anti-A in their blood (group O and group B individuals would have positive results). Group B blood cells could not be used for looking for unusual antibodies since they would react with people who have anti-B in their blood (group O and group A individuals would have positive results). Group AB blood cells could not be used for looking for unusual antibodies since they would react with people who have anti-A and/or anti-B in their blood (group O, group A and group B individuals would have positive results).

Which of the following ABO blood groups has the highest number of H antigen sites on the RBC membrane? - Group A cells - Group B cells - Group O cells - Bombay phenotype

- Group O cells Group O cells contain only H antigen; therefore, blood group O cells have the highest concentration of H antigen in comparison to other blood groups. The other ABO blood groups contain varying amounts of H antigen in addition to their group specific antigen(s). Refer to the following list of blood types listed from the greatest amount of H antigen sites present to the least amount of H antigen sites present: O > A2 > B > A2B > A1 > A1B The classic Bombay phenotype is characterized by the absence of A, B, and H antigens.

In an extreme emergency, if the ABO and Rh type are unknown, which of the following should be given to the patient? - Group O, Rh positive blood - Group AB, Rh negative blood - Group O, Rh negative blood - Any blood type is OK

- Group O, Rh negative blood "Universal donor" is usually applied to group O, Rh negative blood. It lacks ABO and D antigens, so it can be transfused to any ABO and/or Rh type recipient. It does not guarantee complete compatibility due other potential allo-antiboidies in the recipient.

Which of the following contains all the possible phenotypes that could be the result of parents who are group O and group A? - Groups A or O only - Group A only - Group O only - All possible blood groups

- Groups A or O only The group O parent can only supply an O gene to the offspring (OO), but the A parent could provide only A (AA) or either an A or an O (AO). Therefore, the only two possible combinations are OO (group O) or AO (group A).

Which is the first marker (antigen or antibody) which will become positive after exposure to Hepatitis B? - HBsAg - Anti-HBs - Anti-HBe - IgG anti-HBc

- HBsAg HBsAg is detectable 2 to 12 weeks post-exposure during the acute stage and becomes undetectable in 12 to 20 weeks after the development of anti-HBsAg. HBeAg appears after the HBsAg and, in recovering patients, disappears before HBsAg. IgM anti-HBc is the first antibody to appear, and it persists for about 6 months.

What blood system is often tested to either establish or dispute paternity? - HLA - ABO - Rh - Duffy

- HLA Due to the highly polymorphic nature of HLA, or human leukocyte antigens, this system is often used to prove or disprove paternity cases. The ABO blood group is not very polymorphic and, though it can be used to correlate or predict blood types of parents and offspring, it cannot be used to establish paternity. The Rh blood group system is highly polymorphic but is not polymorphic enough to statistically prove or disprove paternity cases. The Duffy (Fy) system is not highly polymorphic and is not useful in establishing paternity.

In which system are DR antigens are found? - Kell system - HLA system - Duffy system - ABO system

- HLA system HLA-DR is an MHC class II(major histocompatibility complex) surface receptor on the cellular surface which is encoded by the human leukocyte antigen complex, or HLA. Kell, Duffy, and ABO antigens are red cell antigens that are inherited independently of the HLA antigens.

A patient presents with platelet refractoriness, or poor response to platelet transfusions. What can be performed to help ensure platelet transfusions will be therapeutic? - ABO matching - HLA typing - Transfusing the platelets with a warmer - Administering an antihistamine before the transfusion

- HLA typing Antibodies to human leukocyte antigens, or HLA, can often cause platelet refractoriness. To prevent this, HLA typing may be performed on the donor platelets to match them to the recipient. ABO matching is typically not performed on platelets. Transfusing the platelets with a warmer will not increase the viability of the platelets or decrease the potential for refractoriness. Using a warmer may be used in patients who have cold agglutinins or are receiving a massive transfusion. Administering an antihistamine may be done when the patient has a history of having mild allergic reactions to transfusions. This will not improve the refractoriness.

In order to avoid repeating pretransfusion testing on a neonate during one hospital admission, all of the following must be true, EXCEPT? - Received only ABO-compatible blood - Received only Rh-compatible blood - No unexpected antibodies in the serum or plasma - Has only received formula for nourishment

- Has only received formula for nourishment The correct answer is has only received formula for nourishment. The neonate's nutrition has no bearing on transfusion requirements. It is unnecessary to repeat pretransfusion testing during any one hospital admission, provided that the infant received only ABO-compatible and Rh-compatible transfusions and had no unexpected antibodies in the serum or plasma.

Based on the evaluation of hematocrit (Hct), blood pressure (BP), pulse, age, and gender, which of the following individuals represents an acceptable allogeneic donor? - Hct is 39%, BP is 160/105, Temp is 99.8, Pulse is 75, Age is 40, and Sex is female - Hct is 37%, BP is 135/85, Temp is 98.6, Pulse is 80, Age is 15, and Sex is male - Hct is 41%, BP is 110/80, Temp is 99.4, Pulse is 65, Age is 65, and Sex is male - Hct is 32%, BP is 120/80, Temp is 98.9, Pulse is 70, Age is 22, and Sex is female

- Hct is 41%, BP is 110/80, Temp is 99.4, Pulse is 65, Age is 65, and Sex is male With certain exceptions, allogeneic blood donors must be at least 17 years of age. The minimum hemoglobin/hematocrit levels for females are 12.5 g/dL or 39%; for males, 13.0 g/dL or 39%. The donor's blood pressure must be no greater than 180 mm Hg (systolic), and no greater than 100 mm Hg (diastolic). The donor's pulse must be regular and fall between 50 to100 beats per minute. Donor's body temperature must not exceed 99.5°F (37.5°C). Exceptions to these donor criteria should be evaluated by the blood bank physician on a case by case basis.

Marcus had a transfusion of packed RBC's 8 months ago following a surgery after a car accident. He is fully recovered and is otherwise healthy. How soon can Marcus donate a unit of blood? - He can never donate a unit of blood. - He can donate in 12 months. - He can donate in 4 months. - He can donate today.

- He can donate in 4 months. The correct answer is, "he can donate in 4 months". The total deferral time following a blood transfusion is 12 months, as long as the donor meets all of the other requirements. Given Marcus received his transfusion 8 months ago, he would need to wait an additional 4 months before he would be eligible to donate a unit of blood.

Which one of the physical examination results below may be cause to reject a donor from blood donation? - Hemoglobin of 12.0 g/dL - Pulse of 80 beats per minute - Temperature of 98.3ºF (36.8ºC) - Blood pressure of 100/75 mm Hg

- Hemoglobin of 12.0 g/dL The correct answer is hemoglobin of 12.0 g/dL. The hemoglobin level of a donor should be greater than or equal to 12.5 g/dL. The pulse of a donor should be between 50 to 100 beats per minute. The donors temperature must be less than or equal to 99.5ºF (37.5ºC). A donors blood pressure must be less than or equal to 180/110 mm Hg.

Which situation will cause a positive DAT (direct antiglobulin test) in the newborn? - Hemolytic disease of the fetus and newborn - Mother is group AB and newborn is group O - Mother is Rh positive and newborn is Rh positive - Mother is Rh positive and newborn in Rh negative

- Hemolytic disease of the fetus and newborn The DAT is ordered to detect IgG or complement proteins bound to patient cells. This can be from autoimmune hemolytic anemia, hemolytic disease of the fetus and newborn (HDFN), a drug-related mechanism, or an antibody reaction to transfused red cells. In HDFN, the fetal cells are coated with IgG that has crossed the placenta from the mother's circulation. With the mother being AB, there would not be any ABO antibodies present to cross the placenta. With the mother being Rh positive, there would not be any antibodies formed from exposure of the fetal red cells, whether the fetus is Rh positive or Rh negative.

Recombinant Factor IX is indicated for which of the following? - Hemophilia A - Hemophilia B - Hemophiliacs with inhibitors - Persons with acquired Factor VII deficiency

- Hemophilia B Persons with hemophilia B are lacking Factor IX. Recombinant Factor IX is used to treat patients with hemophilia B. Factor VIII concentrates are indicated for persons with hemophilia A and persons with von Willebrand's disease. Factor VIIa concentrates are indicated for persons demonstrating inhibitors with hemophilia A or B and for persons with Factor VII deficiency.

Which of the following statements about high-frequency antigens is correct? - High-frequency antigens are common and it is easy to identify their corresponding antibodies. - High-frequency antigens are common, but it is difficult to identify their corresponding antibodies. - High-frequency antigens are rare and it is difficult to identify their corresponding antibodies. - High-frequency antigens are rare, but it is east to identify their corresponding antibodies.

- High-frequency antigens are common, but it is difficult to identify their corresponding antibodies. The correct answer is high-frequency antigens are common, but it's difficult to identify their corresponding antibodies. High-frequency antigens are present in >98% of all individuals. Occurrence of an antibody to these antigens is rare because most individuals have these antigens on their red cells. Looking for antigen negative, compatible blood would be difficult because <2% of the population would be negative for the antigen. Identifying the antibody to a specific high-frequency antigen would be challenging due to the presence of other high-frequency antigens on the panel. All high-frequency antigens tend to be present on every panel cell. Trying to rule out each individual antigen would be difficult since there would be no negative panel cells.

Which blood group is most frequently associated with Cold Agglutinin Disease (CAD)? - Kell - Kidd - Duffy - I

- I Cold Agglutinin Disease (CAD) presents when red cells agglutinate at room temperature. In vivo, a cold autoantibody attaches to red cells in the colder extremities and activates the complement cascade. As the blood warms closer to the core of the body, the autoantibodies dissociate from the red cells, and more complement is activated. This is often associated with autoanti-I or autoanti-i. Kell is a warm antibody and does not activate complement. Kidd can bind complement but is not activated at colder temperatures. Duffy is a warm antibody and does not activate complement.

Which of the following criteria for donor RBC should be used for an exchange transfusion related to both HDFN due to anti-D and ABO HDFN? - Reconstituted with group O fresh frozen plasma - Negative for hemoglobin F - Reconstituted with cryoprecipitate - Irradiated

- Irradiated One of the criterium to consider when selecting blood for exchange transfusion would be the use of irradiated blood to prevent graft versus host disease. Other criteria include using red blood cells < 7 days old resuspended in group AB fresh frozen plasma, hemoglobin S negative blood, group O (or ABO compatible) Rh negative blood, CMV reduced risk products, blood that lacks antigens corresponding to maternal antibody, and compatible crossmatch with maternal serum.

Which class of antibody can agglutinate erythrocytes (RBCs) after anti-human globulin (AHG) is added to the test tube? - IgA - IgE - IgG - IgM

- IgG Some antibodies, such as IgG, do not directly agglutinate erythrocytes (RBCs). This incomplete or blocking type of antibody may be detected by an enhancement medium, such as anti-human globulin (AHG) reagent. If AHG is added, a second antibody binds to the antibody present on the erythrocytes. AHG is created to bind with IgG antibodies at the Fc portion of these antibodies. AHG will bind to both bound and unbound IgG antibodies. When IgG is bound to red blood cells, AHG produces visible agglutination in a test tube. IgA is the predominant immunoglobulin in secretions, such as tears and saliva. IgA forms a complex molecule termed secretory IgG, which is critical in protecting body surfaces against invading microorganisms because of its presence in seromucous secretions. IgE is unique in that it binds strongly to a receptor on mast cells and basophils. Together with antigen, IgE mediates the release of histamines and heparin from mast cells and basophils. IgM is a pentamer with multiple binding sites that enable higher avidity. IgM antibodies, such as anti-A and anti-B, readily agglutinate erythrocytes with the corresponding antigen, A or B, optimally at a colder temperature than IgG without any enhancement agent, such as anti-human globulin (AHG).

A secondary immune response is generally associated with which of the following antibodies? - IgG - IgA - IgM - IgD

- IgG The secondary or anamnestic response has a short lag phase, typically with higher titers than the primary immune response, and IgG predominates. IgA is the immunoglobulin class associated with mucosal immunity. IgM is the immunoglobulin class that predominates in a primary immune response. IgD is involved in the maturation process of B cells, which become immunoglobulin-secreting plasma cells.

Polyspecific antihuman globulin (AHG) reagent used in antiglobulin testing should react with which one of the following? - IgG and IgA - IgM and IgA - IgG and C3d - IgM and C3d

- IgG and C3d Polyspecific antihuman globulin (AHG) reagent contains both anti-IgG activity and anti-C3d activity. Most clinically significant antibodies detected during antibody screening (IAT) are IgG. Polyspecific antihuman AHG was developed for the detection of IgG antibodies, not IgA antibodies or clinically insignificant IgM antibodies.

Which of the following immunoglobulins are capable of fixing complement by the classical pathway? - IgG and IgA - IgM and IgA - IgG and IgM - IgG and IgD

- IgG and IgM The correct answer is IgG and IgM. IgG and IgM can fix complement via the classical pathway. IgA can fix complement via the alternative pathway. IgD is not able to fix complement.

What kind of immunoglobulins are predominantly found in Rh immune globulin? - IgM anti-D - IgG anti-D - IgM anti-A,B - IgG anti-A,B

- IgG anti-D Rh immune globulin is a solution of concentrated anti-D. It is prepared from pooled human plasma of patients who have been hyperimmunized and contains predominantly IgG anti-D. Because RhIg contains IgG anti-D, it can cross the placenta and sensitize fetal Rh positive red cells. Affected infants may be born with a weakly positive DAT, but significant hemolysis does not occur.

A primary immune response is generally associated with which antibody? - IgG - IgA - IgM - IgD

- IgM IgM is a pentamer which is the predominant antibody produced during the primary immune response. Secondary antibodies are usually IgG.

Which of the following is the predominant immunoglobulin class for anti-A and anti-B antibodies in group B and group A individuals? - IgM - IgG - IgA - IgE

- IgM Individuals normally produce antibodies directed against the A and/or B antigen(s) absent from their red blood cells (RBCs). These antibodies have been described as naturally occurring because they are produced without exposure to RBCs. The ABO antibodies are predominantly IgM, and they activate complement and react at room temperature or colder.

A primary immune response typically presents with which class of antibody? - IgG - IgM - IgA - IgD

- IgM The primary immune response typically presents with the greatest level of IgM antibody. Detection of increased IgM antibodies typically demonstrates an acute or early exposure. The secondary immune response presents with a higher titer of IgG antibodies as compared to the primary response. The secondary immune response may also present with greater levels of IgA or IgE. IgD antibodies are typically not tested in the clinical setting.

Which of the following is a common cause of febrile non-hemolytic transfusion reactions? - Bacterial contamination of the blood - Antibody to a platelet antigen - Reaction to plasma proteins - Immune response to leukocytes

- Immune response to leukocytes A febrile nonhemolytic transfusion reaction is an acute transfusion reaction defined as a 1 degree Celsius increase in body temperature within 24 hours of the transfusion (usually within 30 minutes). Other symptoms of febrile nonhemolytic transfusion reactions include chills, nausea, tachycardia, hypertension, and tachypnea. The etiology of febrile nonhemolytic transfusion reactions involves preformed recipient antibodies to leukocytes in the blood product being transfused. This causes the release of pyrogens which are responsible for the fever that is produced. Another mechanism involves cytokines released from leukocytes during platelet storage. These cytokines are able to produce a fever in the recipient when the platelets are transfused. The other listed options are not the cause of febrile nonhemolytic transfusion reactions. Contamination of a blood product can cause transfusion-associated sepsis. An antibody to a platelet antigen can cause post-transfusion purpura. Lastly, a reaction to plasma proteins has been involved in allergic and anaphylactic transfusion reactions.

One risk associated with patients that require chronic transfusions is: - Iron overload - Fear of needles - Transfusion associated graft-versus-host disease (TA-GVHD) - Increased antigen production

- Iron overload The correct answer is iron overload. A long-term complication of RBC transfusion is iron overload. Each unit of red cells contains 225 mg of iron, which puts these patients at risk for iron overload. Fear of needles is not induced by chronic transfusions. TA-GVHD is a rare complication that is more likely in certain populations, but not associated with patients that receive chronic transfusions. Increased antigen production is not something that can be associated with chronic transfusions, but increased antibody production would be.

Which of the following patients are at risk for transfusion-associated graft versus host disease (TA-GVHD) and require irradiated cellular blood products? - Immunocompromised patients including neonates less than 4 months of age and patients receiving chemotherapy. - Post-surgical recipients of pre-operatively donated autologous blood products. - Patients with chronic anemias who are frequently transfused cellular blood products. - Patients with a history of urticarial (allergic) reactions to transfused blood products.

- Immunocompromised patients including neonates less than 4 months of age and patients receiving chemotherapy. Certain recipients have increased risk for developing TA-GVHD. They are: - Neonates less than 4 months of age - Recipients with a congenital or acquired immunodeficiency, such as bone marrow or stem cell recipients, and patients receiving chemotherapy - Recipients of directed donor units from a blood relative - Recipients of HLA matched or crossmatched platelets or granulocytes Recipients of autologous donations are not at risk of TA-GVHD because they are receiving blood they donated for their own post-operative use. Patients who are frequently transfused with cellular blood products to treat chronic anemia are at higher risk of alloimmunization but do not typically require irradiated blood. Patients with a history of urticarial (allergic) reactions to transfusion typically require pre-medication prior to transfusion with antihistamine medications. More severe reactions such as anaphylaxis due to IgA deficiency may require transfusion of washed blood products or IgA deficient plasma products.

Which occurrence is a medical error? - Technologist drops and breaks a bottle of chemistry reagent - Patient is tested and diagnosed with acute leukemia - Analyzer malfunctions and test results are rejected as invalid - Incompatible blood is transfused into a patient during surgery

- Incompatible blood is transfused into a patient during surgery A medical error is a preventable adverse effect of care, whether intended or not, and whether it caused harm to the patient or not. Transfusing incompatible blood is a medical error because it is a mistake that can cause unintended injury to the recipient. If a technologist drops and breaks a bottle of chemistry reagent, this may cause physical damage to the laboratory surfaces, but it would not be a medical error. The reagent may even splash the employee, but it would not be considered a medical error because the technologist was not providing care when he or she dropped the reagent. Testing and diagnosing a patient with acute leukemia would not be a medical error unless the diagnosis was later determined to be incorrect. Analyzer malfunctions and test results being rejected as invalid would not be a medical error unless patient results were released from the instrument during the period of malfunctions and not communicated and corrected.

Red Cells Tested With Serum Tested With Interpretation of ABO Known Antisera Known Red Cells Group Anti-A 4+ A1 Cells 1+ Anti-B 4+ B Cells 0 ? Anti-A,B 4+ Using the information provided above, select the correct ABO group. - Group AB - Group O - Group B - Inconclusive; could be A2B with anti-A1in the serum; further testing is necessary.

- Inconclusive; could be A2B with anti-A1in the serum; further testing is necessary. The forward type in this case suggests group AB; however, there is an unexpected reaction with the A1 cells\in the reverse type. Group O is not the correct answer because the forward typing indicates the presence of A and B antigens on the red cells, and the reverse typing is not consistent with group O reactivity. While the reverse typing results are consistent with reactivity noted in group B people, the forward type indicates A antigen is present, so group B cannot be the correct answer. Because the forward and reverse typing results do not agree, more testing must be performed to identify why the A1 cells are reacting in the reverse type. One possible reason is the patient has a subgroup of A. In ABO typing, reactions with reagent antisera and red cells are generally strong (3 - 4+); weak reactions (less than 3+) should be investigated.

Transfusion-related acute lung injury (TRALI) is a serious blood transfusion complication that can be characterized by all of the following EXCEPT: - Respiratory distress - Pulmonary edema - Acute onset - Increased central venous pressure

- Increased central venous pressure TRALI is an acute, often life-threatening reaction characterized by respiratory distress, hypotension, and pulmonary edema that generally occurs within 2 hours of a transfusion. TRALI must be distinguished from anaphylactic transfusion reactions, transfusion-associated circulatory overload (TACO), and transfusion-related sepsis. Increased central venous pressure is a characteristic finding in TACO, not TRALI.

All of the following can be indications of anemia and the potential need for a transfusion of packed red cells EXCEPT? - Pulse rate greater than 100 beats per minute - Respiration rate greater than 30 breaths per minute - Hemoglobin of 7 g/dL or less - Increased haptoglobin

- Increased haptoglobin The correct answer is increased haptoglobin. A decreased haptoglobin is more likely to be associated with anemia, especially hemolytic anemias. An increased heart rate, an increased respiration rate, and low hemoglobin are all associated with anemia and the potential need for a transfusion of packed RBCs. Normal hemoglobin values are around 12 to 14 g/dL, depending on the sex of the patient. Most consensus groups say that a 7 g/dL hemoglobin is the "trigger value" for a transfusion, although for patients with heart disease, it may be 8 g/dL.

Which of the following choices is the basic technique used to detect unexpected antibodies with a commercial set of reagent cells? - Polyclonal technique - Direct antiglobulin test - Enzyme technique - Indirect antiglobulin test

- Indirect antiglobulin test An antibody screen uses the indirect antiglobulin test (IAT) procedure to detect unexpected antibodies present in the patient serum or plasma. While polyclonal reagents may be used in IAT procedures, there is no polyclonal technique or test used to detect unexpected antibodies. The direct antiglobulin test (DAT) is used to detect IgG or complement proteins bound to patient cells in vivo. An enzyme technique may be used in complex antibody identification procedures but is not used to initially detect unexpected antibodies present in a patient's serum or plasma.

How does hydroxyurea aid in the treatment of sickle cell disease? - Acts as an analgesic in pain management. - Prevents sickle cells from clumping together. - Induces increased production of HbF. - Reduces the number of sickle cells that form.

- Induces increased production of HbF. Hydroxyurea induces increased production of HbF. Most sickle cell patients who have increased levels of HbF experience milder forms of the disease than do patients with normal or low levels of HbF. Therefore, the focus of molecular treatments for sickle cell disease is to increase fetal hemoglobin (HbF). Anti-inflammatory agents are given to serve as an analgesic in pain management for sickle cell patients. Nitric oxide treatment prevents sickle cells from clumping together. Clotrimazole is an over-the-counter antifungal medication. This drug prevents water loss from the red blood cells, which helps prevent the formation of sickle cells.

What red blood cell component is indicated for patients who receive directed donations from immediate family members to prevent transfusion-associated graft versus host disease (TA-GVHD)? - Irradiated Red Blood Cells - Washed Red Blood Cells - Leukocyte-reduced Red Blood Cells - HLA matched Red Blood Cells

- Irradiated Red Blood Cells Gamma-irradiation of blood components containing viable lymphocytes is very effective in preventing TA-GVHD. Irradiation is recommended for all Whole Blood, Red Blood Cell, Platelets, and Granulocyte transfusions to patients at risk. Patients at risk include neonates less than 4 months, patients with an acquired or congenital immunodeficiency, or patients receiving a directed donation from a family member. Irradiation prevents the proliferation of donor lymphocytes with a required dose of 25 Gy to the midplane of the blood container and a minimum of 15 Gy elsewhere. Washed components remove plasma proteins and are recommended for patients with allergies to plasma components, recipients with an IgA deficiency, maternal direct donations with an antibody to HLA to a neonate, complement removal to a patient with Post-transfusion purpura. Leukocyte-reduced components remove>99.9% of leukocytes and prevent the accumulation of cytokines during storage. They reduce the risk of febrile transfusion reactions, the risk of HLA alloimmunization, and the transmission of cytomegalovirus. Leukocyte reduction does not eliminate the risk of TA-GVHD.HLA testing is important for solid-organ and HPC transplantation. HLA-matched platelets are provided to patients with alloantibodies to HLA-A and HLA-B antigens.

Which of the following activities would require that a label be added to the blood label indicating the name and location of a second manufacturer? - Irradiating a unit of red cells or platelets - Shipping a unit to another facility - Thawing a unit of plasma - Receiving a unit from another facility

- Irradiating a unit of red cells or platelets The correct answer is irradiating a unit of red cells or platelets. Irradiating a unit is considered manufacturing and the second manufacturer (name of the facility performing the irradiation) must be listed on the label. Shipping components, thawing plasma, and receiving components are not considered manufacturing and an additional label would not be required.

Transfusion-associated graft versus host disease (TA-GVHD) may be prevented by which of the following? - Washing blood components - Leukoreduction of blood components - Irradiation of cellular products - Using apheresis products

- Irradiation of cellular products Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare but highly lethal complication of transfusion. This immune reaction is mediated by immunocompetent donor lymphocytes in cellular blood components. Immunocompromised patients and recipients who are receiving blood products from donors who share similar HLA phenotypes are at high risk for developing TA-GVHD and should receive blood products that have been irradiated at specific doses required by AABB standards. Irradiation eliminates the ability of the leukocytes to replicate and mount an immune response. Leukocyte reduction (by washing or filters) of the blood component is NOT sufficient to avoid TA-GVHD. Apheresis is used especially to remove specific blood constituents and then returning the remaining blood back to the donor. This will not prevent TA-GVHD.

Which of the following characteristics is consistent with the Kidd blood group system? - Jk(a-b-) red cells are resistant to lysis in 2 M urea - Kidd antigens are destroyed by ficin - Antibodies to Kidd antigens react best at immediate spin - Anti-Jka activity may not react well in a LISS test system

- Jk(a-b-) red cells are resistant to lysis in 2 M urea Kidd antigens are located on the red cell urea transporter. Red cells that lack Kidd antigens resist lysis by 2M urea. Antibodies to Kidd system antigens are enhanced with ficin treated cells. Most antibodies to Kidd antigens are IgG and prefer to react at AHG phase. Antibodies to the Kidd system may be difficult to detect because they can drop in titer in vivo; however, their detection is aided by the use of potentiators such as LISS and PEG.

Which of the following blood group antigen-antibody reactions is enhanced by using enzymes: - Fya - Fyb - M - Jka

- Jka Duffy antigens (Fya and Fyb) and M,N,S antigens are denatured by enzymes. Kidd antigens (Jka, Jkb) are enhanced by enzymes (as well as Rh and Lewis antigens).

An 82-year-old male is a long-time resident of a local nursing facility. He has been to your hospital multiple times over the years and has historically demonstrated antibodies against the K and Fya antigens. He has returned to your hospital following a 2-year absence, and his antibody screen is as follows. Which of the following red blood cells would you crossmatch for this patient? Cell D C E c e K k Fya Fyb Jka Jkb Lea Leb S s M N Lua Lub Cell IgG Phage 1 + + 0 0 + 0 + + 0 + + 0 0 + + + + + + 1 0 2 + + 0 0 + + 0 + 0 + 0 0 + + + + 0 0 + 2 0 3 + 0 + + 0 + 0 0 + + + 0 + 0 + 0 + 0 + 3 0 - K negative - Fya negative - K negative; Fya negative - As long as you perform a full crossmatch and it is compatible, you can use any unit of red cells

- K negative; Fya negative This patient does not currently demonstrate any antibodies, but his historical clinically significant unexpected antibodies cannot be ignored. He must receive units that lack the K and Fya antigens. If the patient is transfused with red cells positive for antigens for which he has made the corresponding antibody, this could lead to a hemolytic transfusion reaction. Any patient with a history of unexpected clinically significant antibodies requires antigen-negative units, even if the corresponding antibodies are not currently reacting in routine testing.

The McLeod phenotype is associated with which of the following antigen systems? - Rh - P - Kell - MNSs

- Kell The McLeod phenotype is associated with a decreased expression of Kell antigens on red cells. When the XK gene is not inherited, the Kx antigen is not expressed on the red cells. The absence of the Kx antigen from red cells and a concurrent reduced expression of the Kell blood group antigens are characteristically associated with a red cell abnormality known as the McLeod phenotype.

Which symptom of HDFN does phototherapy help prevent? - Anemia - Kernicterus - Enlarged spleen - Hydrops

- Kernicterus Phototherapy helps prevent kernicterus by chemically altering the bilirubin in the surface capillaries to harmless substances that can be excreted. Kernicterus is associated with severe cases of jaundice. Phototherapy cannot reverse the red cell destruction, anemia, or edema in the newborn.

Which of the following sources of error will give a false negative result in antihuman globulin testing? - Low pH of saline - Dirty glassware - Samples collected in gel separator tubes - Refrigerated specimen

- Low pH of saline A low pH of saline is indicated as a false negative source of error in antihuman globulin testing. Dirty glassware, samples collected in gel separator tubes, and refrigerated specimens are all indicated as false-positive sources of error in antihuman globulin testing.

Antibodies within which of the following blood group systems are known to result in severe hemolytic transfusion reactions, but are not always detected during pre-transfusion testing in the blood bank? - Duffy - Kell - Lewis - Kidd

- Kidd The correct answer is: Kidd. Kidd is the most common cause of delayed transfusion reactions. The antibody titer for Kidd can drop to undetectable levels several months after primary exposure to the antigen. Upon subsequent exposure to the antigen, a robust antibody response and hemolysis of the offending donor red cells occurs. This is also referred to as an anamnestic response. Duffy Blood Group System antibodies have been implicated in HTRs and DHTRs, but not as frequently implicated in DHTRs as Kidd antibodies. Kell antibodies have been implicated in severe HTRs and less frequently DHTRs. Lewis antibodies are often naturally-occurring, primarily IgM antibodies that rarely cause HTRs.

Proteolytic enzyme techniques may be useful in identifying which of the following antigen groups: - Kell system - Kidd system - MNS system - Duffy system

- Kidd system Reactivity of Kidd antibodies is enhanced by the use of proteolytic enzymes. Antibodies to Kidd antigens are difficult to detect because they show dosage and may not react with heterozygous cells. Kidd antigens can quickly fall to non-detectable levels in vivo and sometimes require complement to react in vitro, thus losing reactivity during storage of serum. The use of proteolytic enzymes is known to enhance antibody reactivity for Kidd, Rh, P1, Lewis, and I antigens. On the other hand, proteolytic enzymes are known to destroy or decrease reactivity to Duffy and MNS systems. Kell antigens are not affected by conventional proteolytic enzyme treatment methods.

A delayed hemolytic reaction occurring a week later is MOST likely caused by: - Volume overload - Kidd system antibodies - Iron overload - ABO incompatibility

- Kidd system antibodies Delayed hemolytic transfusion reactions occur more than 24 hours after a transfusion and result in the hemolysis of red blood cells. Of the causes that are listed, the most likely cause of a delayed hemolytic reaction is Kidd system antibodies. Both Jka and Jkb are often responsible for delayed hemolytic transfusion reactions. Volume overload may cause an acute, nonhemolytic (nonimmunological) reaction. Iron overload may cause a delayed, nonhemolytic (nonimmunological) reaction. ABO incompatibility would cause an acute hemolytic (immunological) reaction.

Which of the following tests is suitable for quantifying the size of fetomaternal hemorrhage (FMH)? - DAT - Kleihauer-Betke test - Rosette testIAT

- Kleihauer-Betke test The Kleihauer-Betke test can quantify the size of a FMH. Flow cytometry may also be used for determining the dose of RhIg. The DAT is done to detect IgG or complement proteins bound to patient cells (in vivo). The rosette test is suitable to screen for FMH but doesn't not quantitate the size of FMH. The IAT is designed to detect in vitro sensitization of red blood cells.

Which of the following best describes reverse typing? - Known antisera used to detect ABO antigens. - Known antigen used to detect ABO antibodies. - Known antigen used to detect ABO antigens. - Known antisera used to detect ABO antibodies.

- Known antigen used to detect ABO antibodies. Reverse typing, also called reverse grouping or back type, uses known reagent red cells (antigen), mostly A1 and B cells, to detect ABO antibodies in the patient's serum.

ABO blood groups were discovered by: - Drew - Lindemann - Hicks - Landsteiner

- Landsteiner Karl Landsteiner discovered the ABO blood groups (A, B, and O) in 1901. He did this by drawing blood on himself and colleagues and then separated the cells and serum which he mixed to observe reactions. He later won the Nobel Prize for his work. Dr. Charles Drew helped develop blood transfusion and preservation techniques which aided in the establishment of blood banks. He was the director of the first American Red Cross blood bank. Edward E. Lindemann was the first person to design a device that could be used for a transfusion. He performed vein-to-vein transfusions using multiple syringes. Braxton Hicks was the first to recommend sodium phosphate as a nontoxic anticoagulant.

Lewis Blood Group System is a human blood group unlike most others. The antigen is produced and secreted by exocrine glands, eventually adsorbing to the surface of red blood cells. Its expression is based on the genetic expression of the Lewis and Secretor genes. Based on the following genotype (Le) (sese), what would you predict the Lewis antigen phenotypic expression to be? - Le(a- b-) - Le(a+ b+) - Le(a+ b-) - Le(a- b+)

- Le(a+ b-) The correct answer is: Le(a+ b-) A person with a functional Lewis gene (Le) and nonfunctional Secretor gene (sese) expresses the phenotype Le(a+b-). A person who is Le(a- b-) lacks the Le gene regardless of secretor status. The Le (a+ b+) phenotype is very rare except among Asians and would require the individual to have a secretor (Se) gene. The Le (a- b+) phenotype would require the individual to have a secretor (Se) gene. The key to answering this question and all others like it is simply memorizing the following chart: Phenotype Lewis Genotype Secretor Genotype Le(a+b-) Le sese Le(a-b-) lele sese or Se Le(a-b+) Le Se Essentially, a functional Lewis gene codes for the enzyme fucosyltransferase 3, which adds fucose to an oligosaccharide precursor at the penultimate position. Meanwhile, a functional Secretor gene codes for the enzyme fucosyltransferase 2, which adds fucose to an oligosaccharide precursor at the terminal position. If a person has Le expression but is a nonsecretor (sese), he will express a phenotype of Le(a+b-). If a person has Le expression and is also a secretor (Se), he will express a phenotype of Le(a-b+). If a person does not have Le expression (lele), it does not matter if he is a Secretor (Se) or nonsecretor (sese), he will always express the phenotype Le(a-b-).

The addition of Low Ionic Strength Solution (LISS) to the testing environment when performing an indirect antiglobulin test is designed to do what? - Lowering the zeta potential - Increasing the zeta potential - Bind IgG antibodies attached to patient RBC's - Bind IgM antibodies found in patient serum or plasma

- Lowering the zeta potential The correct answer is that LISS lowers the zeta potential. - The addition of LISS does not increase the zeta potential. - LISS does not bind IgG antibodies attached to patient RBC's. That is accomplished by the addition of antihuman globulin. - LISS does not bind IgM antibodies found in the patient serum or plasma. Because IgM is a pentamer, lattice formation naturally occurs when it binds in a solution with antigens to which it has specificity.

Lewis Blood Group System is a human blood group unlike most others. The antigen is produced and secreted by exocrine glands, eventually adsorbing to the surface of red blood cells. Its expression is based on the genetic expression of the Lewis and Secretor genes. Based on the following genotype (Le) (Se), what would you predict the Lewis antigen phenotypic expression to be? - Le(a- b-) - Le(a+ b+) - Le(a- b+) - Le(a+ b-)

- Le(a- b+) The correct answer is: Le(a- b+) A person with a functional Lewis gene (Le) and functional Secretor gene (Se) expresses the phenotype Le(a-b+). The key to answering this question and all others like it, is simply memorizing the following chart: Phenotype Lewis Genotype Secretor Genotype Le(a+b-) Le sese Le(a-b-) lele sese or Se Essentially, a functional Lewis gene codes for the enzyme fucosyltransferase 3, which adds fucose to an oligosaccharide precursor at the penultimate position. Meanwhile, a functional Secretor gene codes for the enzyme fucosyltransferase 2, which adds fucose to an oligosaccharide precursor at the terminal position. If a person has Le expression but is a nonsecretor (sese), he will express a phenotype of Le(a+b-). If a person has Le expression and is also a secretor (Se), he will express a phenotype of Le(a-b+). If a person does not have Le expression (lele), it does not matter if he is a Secretor (Se) or nonsecretor (sese), he will always express the phenotype Le(a-b-).

Which one of these Lewis blood group system phenotypes usually produces anti-Lea? - Le(a+b+) - Le(a+b-) - Le(a-b+) - Le(a-b-)

- Le(a-b-) This antibody can occur almost exclusively in the serum of Le(a-b-) individuals and can occur without red blood cell stimulus. It is typically found as a clinically insignificant, naturally occurring IgM antibody. Phenotypes other than Le(a-b-) rarely produce the corresponding antibody.

Which Lewis antigen(s) would be detected when phenotyping the red cells of an adult who has the Le, Se, and H genes? - Lea - Leb - Both Lea and Leb - Neither Lea or Leb

- Leb The correct answer is Leb. Inheritance of both Le and Se genes produces the Leb antigen on red blood cells. The Se gene codes for the enzyme, a-2-L-fucosyltransferase, which adds L-fucose to the type 1 precursor H (type 1). The Le gene codes for another L-fucose which forms the Leb antigen. Some of the precursor chains are not affected by the Se gene and, therefore, form the Lea antigen. Hence, it is possible to see both Lea and Leb in the plasma and secretory fluids. However, only Leb adsorbs onto the red cells of adults (most likely due to competitive binding), causing them to phenotype Le(a-b+).

Which of the following is generally considered equivalent to CMV seronegative RBCs for use in an exchange transfusion to a newborn? - Fresh RBC less than 7 days old - Hemoglobin S negative RBC - Frozen RBC - Leukoreduced RBC

- Leukoreduced RBC Cytomegalovirus (CMV) is a widespread infection that can be transmitted through transfusion. Units that test negative for CMV are set aside for intrauterine transfusion or blood replacement for premature infants and immunocompromised adults. CMV-reduced-risk blood products can also be achieved by leukocyte reduction because the virus resides within intact white cells.

Which one of the following blood group systems may show a cell typing change during pregnancy? - Rh - MNS - Lewis - Duffy

- Lewis The Lewis group antigens are not intrinsic to the red blood cell membrane and can be shed from red blood cells. A distinguishing feature about these blood group antigens is that during pregnancy their expression is diminished on the mother's red blood cells. This can result in the formation of antibodies that are not clinically significant (IgM in nature). The expression of Rh, Duffy, and MNS antigens do not change during pregnancy.

Some soluble blood group antigens exist in fluids such as saliva, urine, and plasma. These antigens can be used to neutralize corresponding antibodies that could mask the presence of other non-neutralizable antibodies. Of the following blood group system antibodies, which one could be neutralized in a manner using these fluids or other natural sources? - Lewis - Kell - Rh - MN

- Lewis The correct answer is Lewis. A combination of Lea and/or Leb substances are present in the saliva of persons who have the Lewis (FUT3) gene. There is a commercially available Lewis substance available for such neutralizations.Kell, Rh, and MN can not be neutralized in this manner as these antigens do not exist in body fluids.Anti-M (Iberis amara) and Anti-N (Vicia graminea) lectins do exist in plant sources but this would not be helpful in neutralizing antibodies.

Which one of the following procedures is used for the proper preparation of platelet concentrate from random whole-blood donors? - Light spin followed by a hard spin - Light spin followed by two hard spins - Two light spins - Hard spin followed by a light spin

- Light spin followed by a hard spin The correct answer is a light spin followed by a hard spin. The first step in the preparation of platelets from random whole blood donors is low-speed centrifugation (light spin). This allows the platelets to remain in the plasma portion of the collection container. The plasma (dubbed "platelet-rich plasma") is then centrifuged at a higher velocity (hard spin) that forces the platelets to the bottom of the satellite bag. The platelet-poor plasma is expressed into another container, and the residual platelets that remain in the bag are resuspended in a small volume of plasma.

Acute transfusion reactions are divided into categories based on all of the following symptoms EXCEPT: - Fever - Liver failure - Allergic reaction - Pulmonary involvement

- Liver failure Acute transfusion reactions breakdown into three groups based on the presenting key clinical symptom: fever, allergic, or pulmonary. Liver failure is not indicated as a symptom in acute transfusion reactions. Fever is indicated in transfusion-associated sepsis (TAS), febrile nonhemolytic transfusion reaction (FNHTR), and acute hemolytic transfusion reaction (AHTR). Allergic (or allergy-mediated) transfusion reactions may be mild or severe. Pulmonary involvement is indicated in transfusion-associated circulatory overload (TACO) and transfusion-related acute lung injury (TRALI).

Which term listed below refers to the process that must be followed when notification is received that a donor of a unit transfused now tests positive for an infectious disease? - Look-back - Donor notification - Minor crossmatch - Major crossmatch

- Look-back The "look-back" process involves the donation facility looking back at previous donations to identify recipients who received a blood product from a donor that is newly testing positive for an infectious disease. The time frame for "look-backs" vary by infectious disease. The goal is to identify recipients who were at risk of receiving an infectious blood product before the donor was testing positive for a particular infectious disease (ex. HIV). Donor notification includes regulations for notification of donors that they currently test positive for an infectious disease. Minor crossmatch involves testing donor serum and recipient red blood cells for compatibility. Major crossmatch involves testing donor red blood cells and recipient serum for compatibility.

Which of the following is true regarding the Lutheran blood group system? - Antii-Lua most often is IgG - Anti-Lub is always IgM - Lua is a high frequency antigen - Lub is a high frequency antigen

- Lub is a high frequency antigen The correct answer is Lub is a high frequency antigen. It is present on over 99 percent of RBC's. Antii-Lua most often is IgG is incorrect. Anti-Lua is most often IgM, therefore is considered clinically insignificant. This also means that if present in a patient, reactions would take place at room temperature. Anti-Lub is always IgM is incorrect. Anti-Lub can be IgG and sometime IgM and should be considered clinically significant. It would most likely react at the AHG phase of testing if present. Lua is a high frequency antigen is incorrect. It is only present on less than 8 percent of the population and therefore would not be considered high frequency.

For granulocyte concentrations, all of the following laboratory tests must be performed on the unit by the donor center EXCEPT? - ABO and Rh - Red Cell antibodies - Infectious disease markers - Lymphocyte enumeration

- Lymphocyte enumeration The correct answer is lymphocyte enumeration. It is not one of the laboratory tests performed on a granulocyte concentrate. ABO, Rh, red cell antibodies, and infectious disease markers should all be performed on granulocyte concentrates. If it is determined that greater than 2 mL of RBCs are present in the unit, then the component should be crossmatched for Rh and HLA compatibility.

Which of the following is responsible for causing transfusion associated graft-versus-host disease? - Platelets - Granulocytes - Monocytes - Lymphocytes

- Lymphocytes Transfusion associated graft-versus-host reactions are caused by the engrafting of immunocompetent T lymphocytes into a severely immunosuppressed recipient. They can be prevented by gamma irradiation of cellular blood components. Platelets, monocytes, and granulocytes are not involved in transfusion associated graft-versus-host disease.

What is the first line treatment for moderate to severe hemophilia A? - Platelets - Lyophilized Factor VIII concentrate - Factor IX complex - Cryoprecipitated AHF

- Lyophilized Factor VIII concentrate The first line treatment for moderate to severe hemophilia A is commercial factor concentrates. If factor concentrates are not available and treatment cannot be safely delayed, cryoprecipitated AHF can be administered.

A newborn presents with neonatal alloimmune thrombocytopenia. What is the most likely cause of this condition? - Maternal antibodies to neonatal platelet antigens - Maternal antibodies to neonatal ABO antigens - Maternal antibodies to neonatal white cell antigens - Maternal antibodies to neonatal D antigen

- Maternal antibodies to neonatal platelet antigens Neonatal alloimmune thrombocytopenia can occur when maternal antibodies attack fetal platelet antigens the neonate inherited from the father. This will destroy the neonate's platelets, causing the thrombocytopenia. Maternal antibodies against neonatal ABO antigens typically causes a mild jaundice as the antibodies lyse the neonatal red blood cells. This is a common condition that will result in elevated bilirubin levels, but the bilirubin levels typically either return to normal on their own or with phototherapy. Maternal antibodies to neonatal white blood cells will present with neonatal alloimmune neutropenia as the antibodies will attach to and destroy the white blood cells. Maternal antibodies to the D antigen result in hemolytic disease of the fetus and newborn, which is a condition that causes moderate to severe hemolysis. This hemolysis can result in fetal demise.

Louisa is a healthy 24-year-old woman that wants to donate blood today. Her hemoglobin, temperature, blood pressure, and pulse are all within the acceptable limits for donating. She's in good health and not taking any medications. She recently divorced her spouse who was a hemophiliac that regularly received factor concentrates. Can Louisa donate blood today? - Yes. There is no deferral for this situation. - No. Louisa can't donate because her husband received factor concentrates. - Maybe, depending on Louisa's last sexual contact with her ex-spouse. - Maybe, depending on what kind of factor concentrate Louisa's ex-spouse received.

- Maybe, depending on Louisa's last sexual contact with her ex-spouse. The correct answer is maybe. What would determine Louisa's eligibility is the last date of sexual contact with her ex-spouse. Persons who have had sex with a person with hemophilia receiving factor concentrates should be deferred for 12 months. Whether Louisa's ex-husband received factor concentrates is not necessarily cause for deferral. The cause for deferral is the potential sexual contact with someone who has received factor concentrations. The type of factor concentrate isn't necessarily cause for deferral. The cause for deferral is the potential sexual contact with someone who has received factor concentrates.

What is the rare phenotype found exclusively in male patients that is caused by X-linked inheritance from a carrier mother, often demonstrating a chronic but well-compensated anemia as well as muscle and nerve disorders? - Fy (a- b-) - McLeod - Jk (a- b-) - U-

- McLeod The correct answer is the McLeod phenotype, which also is indicated by a lack of the Kx and Km antigens, depressed expression of other Kell Blood Group antigens, and may be associated with X-linked chronic granulomatous disease (but this association is not always present). The Fy (a- b-) phenotype is found primarily in the African American population and is associated with resistance to malaria caused by P. vivax. The Jk (a- b-) phenotype is a very rare phenotype, but when present, is most often found in the Polynesian population. The U- phenotype is very rare and only exists in individuals who are both S- and s-.

Platelet specific antigens, also referred to as human platelet antigens (HPAs), are expressed on which of the following? - Membrane glycoproteins - Membrane lipids - Nucleus surface - Nucleus nucleolus

- Membrane glycoproteins Human platelet antigens (HPA's) are expressed on six different platelet membrane glycoproteins. These include GPIIb, GPIIIa, GPIba, GPIbß, GPIa, and CD109.HPA's do not express on lipids. Platelets have no nucleus. Therefore the HPA's can not be found on the nucleus or on the nucleolus.

Which finding best distinguishes immune hemolytic anemia from other hemolytic anemias? - Rouleaux - Positive DAT - Splenomegaly - Increased erythrocyte count

- Positive DAT In the group of disorders referred to as immune hemolytic anemias, erythrocytes are destroyed too early by an immune-mediated process that results from antibodies, complement, or both attaching to the red cell membrane. The presence of immune hemolytic anemia is confirmed by a positive DAT (direct antiglobulin test). Rouleaux is the formation of red cells that are stacked and appear like a stack of coins. This is a characteristic finding in multiple myeloma. Splenomegaly, or an enlarged spleen, may be found in Gaucher's disease or in polycythemia vera. It is not found in immune hemolytic anemia. Increased erythrocyte count is not a finding in immune hemolytic anemia.

An Rh-negative pregnant female has produced anti-D, and the physician has decided to use molecular typing to determine if the fetus is at risk. Which of the following test results makes fetal DNA testing a recommended second step? - Molecular genotyping demonstrates that the father lacks the RHD allele. - Molecular genotyping demonstrates that the father is homozygous for the RHD allele. - Molecular genotyping demonstrates that the father is heterozygous for the RHD allele. - Molecular genotyping demonstrates that the father is heterozygous for the RHCE allele.

- Molecular genotyping demonstrates that the father is heterozygous for the RHD allele. If the father is heterozygous for the RHD allele, the fetus has a 50% chance of inheriting the D gene. Amniocentesis or chorionic villous sampling can be performed at 10-12 weeks to determine if the fetus has the gene for the D antigen. If the father is homozygous for the RHD allele, all offspring will be Rh-positive and do not need to be tested for D. The fetus will be at risk for HDFN and should be monitored. The D antigen is genetically expressed by the RHD allele. The RHCE allele codes for the expression of antigens C, c, E, and e.

Compared to the primary immune response, the secondary immune response typically demonstrates: - Less antibodies produced - A longer lag time - More antibodies produced - A lower affinity

- More antibodies produced The secondary immune response typically presents with a greater number of antibodies that are produced as compared to the primary immune response. The primary immune response typically presents with the generation of less antibodies as compared to the secondary immune response. The secondary immune response presents with a shorter lag time as compared to the primary immune response. The secondary immune response typically presents with antibodies that have a higher affinity as compared to those from the primary immune response.

Which of the following set of conditions would NOT allow HDFN to occur as a result of Rh incompatibility? - Mother Rh-negative, father Rh-positive - Mother Rh-negative, baby Rh-positive - Mother Rh-negative, father Rh-negative - Mother Rh-negative, father Rh-unknown

- Mother Rh-negative, father Rh-negative If both parents are Rh-negative, the baby would also be Rh-negative, and HDFN due to Rh incompatibility would not occur. For Rh HDFN to occur, the baby must be Rh-positive and the mother Rh-negative. If the father is Rh-positive, then there is a likely probability the baby will be Rh-positive, and thus the potential for Rh HDFN. If the Rh type of the father is unknown, it is common to assume that the father is Rh-positive due to statistical probability, and thus the potential for Rh HDFN exists.

In immunohematology, an antithetical relationship exists between M antigen and which of these antigens? - K antigen - S antigen - Lu6 antigen - N antigen

- N antigen The correct answer is N antigen. The M antigen has an antithetical relationship with N antigen. Antithetical is the term used to describe a pair of antigens that are coded by different alleles on a single gene. The K antigen has an antithetical relationship with k antigen. The S antigen has an antithetical relationship with s antigen. The Lu6 antigen has an antithetical relationship with Lu9.

If a patient is determined to have type AB blood, what antibody would be found in his/her serum? - Anti-A - Anti-B - Anti-A and Anti-B - No Anti-A, no Anti-B antibodies

- No Anti-A, no Anti-B antibodies Type AB individuals will have neither anti-A nor anti-B antibodies in their plasma. Individuals who type A will have anti-B and will not have anti-A. Individuals who are type B will have anti-A and will not have anti-B. In type O patients, both anti-A and anti-B will be present since the patient does not have A or B antigens on their red cells.

What is the appropriate deferral period from donating blood for a 34-year-old female who miscarried in her first trimester? - 8 weeks - 6 weeks - 2 weeks - No deferral

- No deferral A miscarriage or abortion in the first or second trimester is not cause for deferral from donating blood or blood products in an otherwise healthy woman. Female donors whose pregnancy terminated in the third trimester or who delivered should be deferred for a minimum of 6 weeks. Some exceptions can be made for autologous donors. Additionally, deferral may be longer than 6 weeks under certain circumstances such as receipt of a blood transfusion after delivery.

Can an autologous donor donate blood at 4 PM on Monday if she is having surgery at 10 AM on Wednesday? - No, the minimal allowable time between the last donation and surgery is 72 hours. - No, the minimal allowable time between the last donation and surgery is eight weeks. - Yes, the patient can donate, but only half a unit. - Yes, an autologous donor can donate up to 24 hours prior to surgery.

- No, the minimal allowable time between the last donation and surgery is 72 hours. It is generally accepted that the minimal allowable time between the last autologous donation and surgery is 72 hours, though some facilities may have a cutoff time that is further out than 72 hours. If an autologous blood donation was made 8 weeks before surgery, the donated blood would expire before the surgery date. Less than the normal blood donation volumes are only taken if the donor is less than 110 pounds. An autologous blood donation made 24 hours prior to surgery would not allow enough time for the patient's bone marrow to replace the blood that was lost during donation.

Which blood group antibody(ies) would you find in a group AB individual? - Anti-A - Anti-B - Anti-A, Anti-B - None

- None Group AB individuals will have both the A antigens and B antigens on their red blood cells. These patients will NOT have anti-A or anti-B in their serum because those antibodies will go against their own red blood cell antigens. Group B patients will not have A antigens but, will have B antigens on their cells. They will have anti-A in their serum, but they will not have anti-B in their serum, which will give positive results with A cells and negative results B cells. Group A patients will have A antigens, but not B antigens on their cells. They will not have anti-A in their serum, but they will have anti-B. Group O patients will not have A or B antigens on their cells and they will have anti-A and anti-B in their serum.

A solution of gamma globulins containing anti-Rh(D) is given to an Rh(D) negative mother to: - Prevent fetal cells from initially sensitizing the mother - Neutralize any of the child's antibody that may have passed the placental barrier - Neutralize any natural maternal antibodies present - Prevent greater antibody response in a previously sensitized mother

- Prevent fetal cells from initially sensitizing the mother RhIG (anti-D) is given to Rh-negative mothers to prevent D antibody production, which can cause harmful effects in future pregnancies with a Rh-positive fetus. The administered anti-D will bind to fetal Rh-positive red blood cells that may enter maternal circulation during pregnancy (in vivo). Therefore, the mother will not produce anti-D herself and preventing sensitization.

Anti- A= 0 Anti-B= 0 A1 cells= 4+ B cells= 4+ Interpretation of ABO Group= ? Using the information provided above, what is the correct ABO group? - Unable to interpret - O - AB - Either A or B

- O In this case, the forward type shows no agglutination; the patient's red blood cells do not contain the A or B antigens. In the reverse type, the patient demonstrates anti-A and anti-B, which correlates with the results obtained from the forward typing. The blood is group O. The blood testing is interpretable as group O. Group AB patients would have negative results with A1 cells & B cells and positive results with anti-A & anti-B. Group A patients would have negative results with A1 cells & positive results with B cells, and positive results with anti-A & negative results with anti-B. Group B patients would have positive results with A1 cells & negative results with B cells, and negative results with anti-A & positive results with anti-B.

Which one of the ABO groups listed below has the MOST H antigen? - A1 - A1B - B - O

- O The amount of H antigen varies depending on the ABO group that is inherited. For example, group O has the most H antigen, followed by A2 then B, and A2B then A1.A1B has the least amount of H antigen.

Which of the following packed red blood cell ABO types would be appropriate for transfusion to an O negative patient of child-bearing age? - O negative only. - AB negative and O negative only. - AB negative, A negative and B negative only. - AB negative, A negative, B negative and O negative only.

- O negative only. O negative recipients can only receive O negative blood. AB negative blood has the A and B antigens and the O negative recipient has both Anti-A and Anti-B in their blood. A negative blood has the A antigen. B negative blood has the B antigen. Neither A nor B would be appropriate for a type O patient because the O person has Anti-A and Anti-B in their plasma.

Which of the following is the most prevalent blood type found in the United States? - O positive - A positive - B positive - O negative

- O positive Type O phenotype is the most frequent among all ethnic groups in the United States, followed by Type A, Type B, and Type AB. The D antigen is present in 85% Whites, and 92% Blacks.

If an individual has blood type O, which of the following are possible genotypes? - AO and OO - BO and OO - OO only - AO, BO, and OO

- OO only The O gene is considered an amorph, as no detectable antigen is produced in response to the inheritance of the gene. Therefore, the group O phenotype is an autosomal recessive trait with the inheritance of two O genes (genotype OO) that are nonfunctional. An individual who has the phenotype A can have the genotype AA or AO. An individual who has the phenotype B can have the genotype BB or BO.

What are the possible ABO genotypes of offspring of parents whose genotype is AO and BO? - OO, AO, BO, AB - AO and BO - OO and AB - AB, AO, and BO

- OO, AO, BO, AB The offspring from this set of parents can yield each of these genotypes OO, AO, BO, AB, which can lead to group O, group A, group B, and group AB offspring. This can be determined by the utilization of a simple Punnett square. There is a 25% chance for inheritance of each of the possible genotypes. The only genotypes this mating would not produce are AA and BB.

All of the following are advantages of performing the computer crossmatch EXCEPT? - Greater flexibility in staffing - One determination of recipient's ABO group is made - Better management of blood bank inventory - Reduced volume of sample needed on large crossmatch orders

- One determination of recipient's ABO group is made A requirement for the computer crossmatch is that there need to be two determinations of the recipient's ABO group. The preference is to have two separately drawn samples available for testing. Some of the advantages of the computer crossmatch are that there can be greater flexibility in staffing, better management of blood bank inventory, reduced volume of sample needed on large crossmatch orders, increased time efficiency, and potential for a centralized transfusion service.

Which patient population benefits from HLA matching to provide patients with the best outcomes? - Transfusion recipients - Organ transplant recipients - Neonates - Patients with high-incidence antibodies

- Organ transplant recipients Patients who receive organ and hematopoietic progenitor cell transplants respond best if the HLA antigens are matched between the donor and the recipient. Routine transfusion recipients do not require HLA matching. For patients who experience allergic or anaphylactic reactions from transfusions, blood unit irradiation would be helpful. There is no indication that HLA typing would be beneficial for neonates. Human leukocyte antigens are present on white blood cells, so a patient with antibodies to high-incidence red cell antigens should not have a reaction with the HLA.

All of the following are required to be in a machine-readable format on a blood component label, EXCEPT: - ABO & Rh of the donor - Product code - Collection facility - Outdate

- Outdate The correct answer is outdate. The outdate may be handwritten, but must be legible. 21 CFR 606.121 requires this information be machine-readable: - A unique collection facility identifier - Lot number relating to the donor - Product code - ABO and Rh of the donor

What is a common difference between paroxysmal cold hemoglobinuria (PCH) and cold hemagglutinin disease (CHD)? - PCH is a cold autoimmune anemia while CHD is acquired - PCH is a warm autoimmune anemia while CHD is room temperature - PCH is caused by an IgG antibody while CHD is usually caused by an IgM antibody - PCH is typically an IgM antibody while CHD is usually caused by an IgE

- PCH is caused by an IgG antibody while CHD is usually caused by an IgM antibody The correct answer is PCH is caused by an IgG antibody while CHD is usually caused by an IgM antibody. PCH is caused by Donath-Landsteiner (bi-phasic) IgG antibodies. CHD is most commonly caused by anti-I or anti-i which are both IgM antibodies. PCH and CHD are generally acquired autoimmune hemolytic anemias. PCH antibodies bind complement to the red cells at 4°C and cells undergo complement-mediated hemolysis at 37°C. CHD antibodies react best at 4°C, but can also react up to 31°C.

A patient with multiple myeloma has the following reactions in the ABO typing: Anti-A= w+ Anti-B = w+ Anti-A,B = w+ Auto control = w+ A1 Cells = 4+ B cells = 4+ What is probably causing these results? - Rouleaux - Subgroup of A - Patient has hypogammaglobulinemia - Patient has selective IgA deficiency

- Rouleaux The correct answer is rouleaux. Rouleaux is the stacking of red blood cells and it occurs when patients have abnormal globulins such as in Multiple Myeloma. This is most likely causing false agglutination in the ABO typing. A subgroup of A should not show a reaction in the auto control. A patient with hypogammaglobulinemia would have weakened reverse type reactions, not forward type reactions. A patient with a selective IgA deficiency would not show any abnormalities in their ABO typing.

A pregnant female has been injected with Rh Immune Globulin (RhIG) antenatally (28 weeks gestation) and has a positive antibody screen at delivery. The antibody has been confirmed as anti-D alone and reacts only weakly (1+ in the indirect antiglobulin test). This antibody may be the result of: - Massive fetomaternal hemorrhage at delivery - Passive anti-D (RhIg) received at 28 weeks. - Wharton's jelly contaminating the sample - Patient has an autoantibody

- Passive anti-D (RhIg) received at 28 weeks. Rh Immune Globulin is administered at 28 weeks of gestation and at delivery to help prevent pregnant women from becoming actively immunized to the D antigen. RhIG is given because during pregnancy and at delivery fetal blood can enter maternal circulation. This exposure to the D antigen puts the mother at risk for becoming sensitized and making an anti-D. Women who are Rh negative carrying an Rh positive fetus now receive RhIG at 28 weeks (antenatal) and at delivery (within 72 hours of delivery) to clear fetal red blood cells from maternal circulation. The RhIG can attach to fetal red blood cells which are then cleared by macrophages. At delivery some Rh negative women have a weakly reactive anti-D still in circulation from RhIG administration at 28 weeks of gestation (antenatal). The anti-D has been demonstrated to stay in circulation 2 months or even longer in some cases. Massive fetomaternal hemorrhage may sensitize a woman but this would not be detected at delivery. Wharton's jelly would be present in the cord sample from the baby and may cause incorrect results (rouleaux) for the baby. The mother is Rh negative since she received RhIG so the anti-D present is not an autoantibody.

A maternal sample is collected 2 hours after delivery and a type and screen is performed. The screen is weakly positive and an anti-D is identified. Which of the following is the most likely cause of the positive antibody screen? - Passive anti-D from RhIG given at 28 weeks. - Anti-D formed during delivery - Anti-D in neonate - False positive result

- Passive anti-D from RhIG given at 28 weeks. Rh Immune Globulin is administered at 28 weeks of gestation and at delivery as a way to help prevent pregnant women from becoming actively immunized to the D antigen. RhIG is given because during pregnancy and at delivery fetal blood can enter maternal circulation. This exposure to the D antigen can put the mother at risk for becoming sensitized and making an anti-D. Women who are Rh negative carrying an Rh positive fetus now receive RhIG at 28 weeks (antenatal) and at delivery (within 72 hours of delivery) to clear fetal red blood cells from maternal circulation. The RhIG can attach to fetal red blood cells which are then cleared by macrophages.

Which of the following is considered an indication for Rh immune globulin (RhIG) administration in postpartum women? - Long term protection - Antibody blocking - Passive protection - Active immunity

- Passive protection Active immunization induced by the D antigen can be prevented by the concurrent administration of the corresponding RBC antibody (anti-D). Rh-negative non-immunized mothers expecting Rh-positive infant(s) should receive Rh immune globulin (RhIG) in the third trimester or at 28 weeks' gestation. Postpartum Rh-negative non-immunized mothers should receive RhIG immediately after delivery of an Rh-positive newborn. For passive protection, RhIG therapy can be administered within 72 hours after delivery as it may be effective against formation of anti-D. There is no long term protection against the development of Rh antibodies due to potential for patient exposure in subsequent pregnancies. The mechanism for RhIG therapy does not block antibody; it attaches to the fetal Rh-positive RBCs and removed by macrophages in the maternal spleen.

When is a computer crossmatch acceptable? - Patient has a history of anti-Jka but the antibody screen on the current sample is negative - Patient has a positive antibody screen and anti-D is detected - Patient has no history of clinically significant antibodies detected and the antibody screen on the current sample is negative - Patient has a history of anti-Fya but the antibody screen on the current sample is negative

- Patient has no history of clinically significant antibodies detected and the antibody screen on the current sample is negative Crossmatching allows for a final check of ABO compatibility and can be used to detect antibodies that would otherwise be missed using an antibody screen (antibodies to low incidence antigens). Studies have shown that computer crossmatches are as safe as serologic immediate spin testing. The requirements for a computer or electronic crossmatch include: Current testing for unexpected antibodies must be negative and the patient cannot have a history of any such antibodies. Other criteria include at least two matching ABO/Rh types on file (one must be from current sample). A history of anti-Jka or anti-Fya would disqualify a patient for a computer crossmatch. Additionally, positive antibody screen and anti-D identified would also rule out the use of a computer crossmatch.

You receive a call in the blood bank, reporting a transfusion reaction. You ask the nurse to stop the red blood cell transfusion immediately and return the unit of blood and all related forms to the blood bank. You also ask for a new patient blood specimen to be drawn and sent to the blood bank. You receive the requested items 15 minutes later. What will you do FIRST as part of your investigation? - Perform an antibody screen and DAT on the pre-transfusion and post-transfusion specimens. - Perform a clerical check, centrifuge the pre-transfusion and post-transfusion patient specimens and examine the plasma for hemolysis and icterus. - Issue a different unit of blood to this patient but only after the original unit has been returned to blood bank. - Do nothing, as you issued an O Negative red blood cell unit to the patient and that proves that the unit is compatible.

- Perform a clerical check, centrifuge the pre-transfusion and post-transfusion patient specimens and examine the plasma for hemolysis and icterus. The correct answer is: perform a clerical check and centrifuge the pre-transfusion and post-transfusion patient specimens examining the plasma for hemolysis and icterus. Spinning down the tubes will allow you to examine the plasma before and after transfusion for a change in color. Hemolysis and/or icterus in the post-transfusion specimen, when compared with the pre-transfusion specimen, would be an indication of a possible hemolytic transfusion reaction. Clerical errors account for the vast majority of transfusion reactions. Performing a DAT will be part of your analysis but not your first act. You will not issue another unit of blood to this patient until the investigation of the transfusion reaction is complete unless the Medical Director deems it necessary. While giving O Negative blood may rule out an ABO incompatibility, even an ABO incompatibility cannot be completely ruled out until you have retyped the patient. Giving O Negative blood also will not prevent a transfusion reaction caused by a non-ABO clinically significant antibody.

Anti-U antibodies can be produced by which of the following genotypes? - M-N- - S+s+ - S+s- - S-s-

- S-s- Absence of or an altered glyocyphorin B can result in red cells lacking the S, s, and U antigens. These individuals, if exposed to blood with S antigens, s antigens, or both will also be exposed to the U antigen and have the potential to produce anti-U. In this same scenario, the person receiving blood could also produce anti-S and/or anti-s. The U antigen is present on red cells when a person has S antigens, s antigens, or both.

What should be done FIRST if a donor unit of red blood cells is found to be incompatible at the antiglobulin phase but compatible at immediate spin with several different recipients? - Repeat the ABO grouping on the incompatible unit using different sera - Do a panel made up of red cells having all low-frequency antigens - Perform a direct antiglobulin test (DAT) on the donor unit - Obtain a new specimen and repeat the minor crossmatch

- Perform a direct antiglobulin test (DAT) on the donor unit If a donor unit of red blood cells is found to be incompatible at the antiglobulin phase with several recipients, the possibility of antibody coating the red blood cells is likely. A DAT should be performed on the donor unit. The antiglobulin phase of a crossmatch involves the addition of anti-human globulin (AHG). If donor cells are coated with antibody from a positive DAT the AHG will crosslink the donor cells and the crossmatch with be incompatible. ABO grouping does not need to be repeated since ABO incompatibility would be seen at immediate spin. It is unlikely that multiple recipients have alloantibodies to a low frequency antigen present on the donor unit. Antibodies to low frequency antigens are uncommon due to the low percent of patients stimulated (since not many donor cells have the antigen) to produce antibodies during a transfusion. Lastly, a new specimen is not needed for a minor crossmatch since plasma is not being transfused.

While working at a blood bank laboratory, you hear chimes over the hospital loudspeaker system announcing the birth of a baby. Thirty minutes later, you receive a cord blood specimen that you identify as O positive. You previously received the mother's specimen and she was O negative with a negative antibody screen. What is the next action? - Issue one vial of RhIg - Perform a Kleihauer Betke stain - Nothing - Mom is not at risk for anti-D - Perform a fetal bleed screen

- Perform a fetal bleed screen Because the baby is D positive and the mom is D negative and not currently immunized to the D antigen, mom will need to receive at least one 300 µg dose of RhIg. However, we must first perform a fetal bleed screen to determine if a fetal-maternal hemorrhage (FMH) has occurred. If a FMH occurred, the fetal bleed screen would be positive, and a Kleihauer Betke stain is required. In some institutions, FMH is quantified with flow cytometry studies. If the FMH is 30 mL or less, 1 vial of RhIg is indicated. For a FMH larger than 30 mL, a calculation is completed to determine how many vials of RhIg must be issued.

A D-negative mother gives birth to a baby that tests as D-negative in the immediate spin phase. What step should be performed next? - Calculate dose for RhIg - Perform a weak D test - Administer one dose of RhIg - Perform a Kleihauer-Betke stain

- Perform a weak D test A weak D test must be performed to ensure that the neonate is D-negative instead of weak D-positive due to the potential for the mother to form anti-D to any D-positive neonate. If the neonate is truly D-negative, RhIg is not indicated, so there is no need to calculate the dose or give a prophylactic dose. The Kleihauer-Betke stain will only quantify fetal red cells; it does not differentiate between D-negative and D-positive cells.

What is the deferral period from donating blood for someone who is or has taken Tegison© for severe psoriasis? - Permanent deferral - 1 month following last dose - 2 weeks - No deferral

- Permanent deferral Persons taking or who have ever taken Tegison© are permanently deferred. Blood or blood products from persons who have ever taken Tegison© can cause birth defects if transfused to a pregnant woman. Other medications such as Proscar© and Avodart © (both used to treat enlarged prostates), Propecia© (used to treat bladness), Accutane© (used to treat severe acne), and Soriatane© (used to treat severe psoriasis) are all cause for deferral. Proscar©, Propecia©, and Accutane© users are deferred for one month following the last dose. Persons who have used Avodart © are deferred for six months following the last dose. Persons who have used Soriatane© are deferred for three years following the last dose.

What is the acceptable way to thaw Fresh Frozen Plasma? - Leaving it at room temperature away from agitation - Refrigerating the FFP on a bottom rack - Placing the FFP in a 37º C water bath - Placing the FFP in a 121º C or higher in a steam sterilizer

- Placing the FFP in a 37º C water bath Fresh frozen plasma must be thawed at a maximum of 37oC in a water bath or similar FDA-approved equipment that has been validated and is temperature monitored. When using a water bath, the FFP should be wrapped in a plastic liner to prevent contamination of the administration ports. Any other non-approved method is not permitted.

Bacterial contamination is MOST likely in which of the following blood products? - Packed red blood cells - Frozen red blood cells - Platelets - Fresh frozen plasma

- Platelets The correct answer is platelets. Bacterial contamination of platelets is most likely because they are stored at room temperature. The estimated rate of bacterial contamination in platelets is around 10%. Bacterial contamination is possible in packed red blood cells stored in the refrigerator, but the estimated rate of bacterial contamination is only around 0.2% Frozen red blood cells are not likely to have bacterial contamination. Fresh frozen plasma is not likely to have bacterial contamination.

Which one of the following blood components would be MOST appropriate for a 9-yr old girl who is suspected of having immune thrombocytopenic purpura (ITP)? - Packed red blood cells - Cryoprecipitate - Platelets - Fresh frozen plasma

- Platelets The correct answer is platelets. ITP is bleeding owing to a decreased number of platelets, thus the most appropriate treatment would be to transfuse platelets. In more severe cases, IV immunoglobulin may be administered. Packed red blood cells, cryoprecipitate and fresh frozen plasma would not increase the patient's platelet count. NOTE:It is important to know the difference in treatment for ITP and Thrombotic Thrombocytopenic Purpura (TTP). It is appropriate in cases of ITP to give platelets, however, it is not appropriate to give platelets in cases of TTP. The most effective treatment for TTP is plasma exchange using fresh-frozen plasma or cryoprecipitate poor plasma.

In blood bank agglutination reactions, the zeta potential (a force exerted by ions in the saline solution that causes repulsion between red blood cells in the saline suspension) can be reduced by treating the sensitized cells with: - Polyclonal antibody reagents - Polyethylene glycol (PEG), albumin, or proteolytic enzymes - Monoclonal antiglobulin reagents - Coombs check cells

- Polyethylene glycol (PEG), albumin, or proteolytic enzymes Antigen-antibody reactions will not occur, or will be weak, if a force exerted by ions in the saline solution cause repulsion between two adjacent red blood cells. The zeta potential can be reduced by treating the red blood cells with proteolytic enzymes such as papain and ficin, or using various colloidal diluents such as albumin or PEG. Polyclonal antibody reagents, monoclonal antiglobulin reagents, and Coombs check cells are all valuable tools used in the blood bank but they do not decrease zeta potential and they are not used to bring red blood cells closer together.

All of the following are reasons for conducting compatibility testing EXCEPT: - Prevent recipient alloimmunization - Verify ABO and Rh - Select proper blood products - Detect antibodies against donor cells

- Prevent recipient alloimmunization Compatibility testing is performed by the blood bank laboratory to detect serologic incompatibilities that might result in decreased survival of donor red cells in the transfused patient, but cannot prevent alloimmunization of the recipient to antigens on transfused cells since patients and donor units are not phenotyped for every antigen prior to transfusion. The term compatibility testing, also known as pretransfusion testing, describes a set of procedures required before blood is issued as being compatible. Compatibility testing includes verification of ABO and Rh, selecting the proper blood products for transfusion, and detecting antibodies against donor cells to help avoid potential transfusion reactions.

In which situation is gamma irradiation of cellular blood components required? - Prevention of post-transfusion purpura - Prevention of Graft-Versus-Host (GVH) disease - Sterile components - Prevention of non-cardiogenic pulmonary edema

- Prevention of Graft-Versus-Host (GVH) disease Transfusion related Graft-Versus-Host disease is a rare condition usually following transfusion of patients whose immune system is severely compromised. It occurs when T lymphocytes present in the transfused unit replicate and attack the tissues of the recipient. Gamma irradiation prevents this condition by inactivating T lymphocytes in the donor unit. Gamma irradiation of cellular blood components is required when: 1.The donor is a blood relative of the recipient, 2. Intrauterine transfusions, 3. The recipient has a selected immunodeficiency condition, 4. The recipient has received a bone marrow transplant. Post transfusion purpura and pulmonary edema are adverse effects of transfusion not related to irradiation of blood components. All blood components are considered sterile unless the unit has been compromised or becomes an open system.

Washing red cells may be performed to remove what from the unit? - White blood cells - Platelets - Plasma - Proteins

- Proteins Washing red cells removes remaining plasma proteins that are present in the unit. Washing red cells may remove some white blood cells, but it is not an efficient way to do so. Irradiation of the unit is the best approach when removing white blood cells. During collection the whole blood unit undergoes a light spin to separate the red blood cells from the plasma and platelets. The platelet-rich plasma is diverted into another unit for further processing. Though there is some residual plasma in the red cell unit, it is not enough to cause a reaction.

Which adsorption technique removes cold (IgM) antibodies, particularly anti-I specificities? - Cold autoadsorption - Warm autoadsorption - Differential (allogeneic) - Rabbit erythrocyte stroma (RESt)

- Rabbit erythrocyte stroma (RESt) RESt removes cold (IgM) antibodies, particularly anti-I specificities. However, it may adsorb anti-B and other IgM antibodies. Cold autoadsorption uses patient red cells to remove cold autoantibodies to determine whether alloantibodies are present. Warm autoadsorption uses patient red cells are used to remove warm autoantibodies to determine whether alloantibodies are present. Allogeneic adsorption uses known phenotyped red cells to separate specificities: 1) warm autoantibodies from alloantibodies 2) alloantibodies with several specificities.

Which characteristic best describes IgG antibodies produced against red blood cells? - Are naturally occurring - Cannot be identified using the AHG test - React best at room temperature - React best at 37o Celsius

- React best at 37o Celsius There are two types of antibodies that concern blood banking: one is naturally occurring and the other is immune. Most immune red blood cell antibodies are IgG antibodies that react best at 37oC and require the use of antihuman globulin for detection. Most naturally occurring antibodies are IgM cold agglutinins which react best at room temperature or lower.

Rh antibodies generally: - React best at 4°C. - React best at room temperature. - Generally do not react at any temperature. - React best at 37°C.

- React best at 37°C. The correct answer is react best at 37°C. Rh antibodies react best at 37°C, they do not react at 4°C or room temperature.

What characteristic is usually associated with IgM antibodies directed against red cells? - React best at 37oC - Appear after heated incubation - Are identified using the AHG test - React best at room temperature

- React best at room temperature IgM antibodies typically react best at room temperature. The other choices listed including: reacting best at 37oC, appearing after heated incubation, and identification using the AHG test, are all characteristics of most IgG immunoglobulins, but not IgM immunoglobulins.

Antibodies in the Rh system typically exhibit which one of the following characteristics? - Reacts best at 37ºC and AHG - Reacts best at room temperature - Shows hemolysis better than agglutination - Reacts best at 4oC

- Reacts best at 37ºC and AHG Most Rh antibodies are IgG immunoglobulins and react optimally at 37oC or after antiglobulin testing in any method used for antibody detection.

Before testing, all cord cells should be thoroughly washed in order to: - Remove Lea substances - Remove H substances - Remove Wharton's jelly - Hemolyze contaminating maternal cells

- Remove Wharton's jelly The proteins found in Wharton's jelly can interfere with immunohematologic tests. Lewis system antigens are not found on newborn red cells, so would not cause problems with cord blood testing. H antigen is present on red cells from persons who have not inherited the hh genotype, so the presence of this antigen or substance would not interfere with testing. If a cord blood sample is suspected of having maternal blood contamination, a heel-stick sample should be collected from the newborn.

When administering fresh frozen plasma (FFP), which one of the following is considered standard blood bank practice? - Should be ABO compatible with the recipient's red blood cells - Must be the same Rh type as the recipient - Is appropriate for use as a volume expander - Component should remain frozen when it is issued

- Should be ABO compatible with the recipient's red blood cells FFP should be ABO-compatible with the recipient's red blood cells, but does not need to be the same Rh type as the recipient because it is a cell-free product. FFP should not be used as a volume expander; preferably, use a safer product such as serum albumin. This limits the exposure to transfusion-transmitted diseases and lowers the risk of transfusion reactions. FFP is indicated for patients that are actively bleeding or to treat clotting factor deficiencies. It may be used as a replacement fluid during plasma exchange procedures. FFP must be thawed prior to being issued for transfusion purposes.

When performing an antibody screen, both the screen cells are 4+ at immediate spin and W+ at AHG. The antibody panel shows 4+ reactions at immediate spin and W+ reactions at AHG and there is no specific match to the reaction pattern. The auto control is negative. What would be a logical next step? - Have patient redrawn - Repeat testing using warmed patient sample/reagent and just do AHG reading - Run an enzyme panel - Use acidified reagents

- Repeat testing using warmed patient sample/reagent and just do AHG reading Phase of reactivity is primarily at immediate spin (4+) and reactions get weaker at AHG (w+). There is no specific pattern of reactivity and the auto control is negative which rules out an autoantibody. This is a strong cold antibody which is still slightly present after incubation and washing. Activation and binding of the antibody takes place at room temperature or colder. Warming the sample/reagents and eliminating this phase will prevent the antibody from binding. Cold antibodies usually are more of a nuisance to blood bankers and are not clinically significant. There does not seem to a problem with the sample so the patient does not need to be redrawn. Enzymes can be used to enhance reactions of certain antibodies but in this case the antibody present appears to be one that may not be clinically significant so enhancement is not needed. Acidified reagents can be used as a way to enhance certain antibodies as well.

What procedure is used by the laboratory personnel to confirm ABO typing by using cells with known blood groups? - DAT - Forward typing - Reverse typing - Antibody identification panel

- Reverse typing Reverse typing is using known cells (reagent A1 cells and reagent B cells) to detect naturally occurring ABO antibodies (anti-A and anti-B) in the patient who is being typed and helps to confirm the forward typing. The DAT (direct antiglobulin test) is ordered to detect IgG or complement proteins bound to patient cells. Forward typing uses reagent anti-A and reagent anti-B to determine the presence of A or B antigens. The forward and reverse typing results must agree for the ABO result to be valid. The antibody identification panel is required to determine the specificity of a red cell antibody. The antibody identification panel cells are individual group O donors (no A or B antigens) packaged in sets of 10 or more and who also possess the majority of the most frequently inherited red cell antigens.

Which of the following accurately represents reverse typing? - Reverse typing is performed using known reagent antisera to detect ABO antigens on the patient's red blood cells. - Reverse typing is performed using known reagent red blood cells to detect ABO antibodies in the patient's serum or plasma. - Reverse typing is performed using known reagent screening cells to detect clinically significant antibodies in the patient's serum or plasma. - Reverse typing is performed using known reagent antisera to phenotype donor red blood cells for clinically significant antigens.

- Reverse typing is performed using known reagent red blood cells to detect ABO antibodies in the patient's serum or plasma. Reverse typing is performed using reagent A1 cells and B cells that are tested against the patient's serum or plasma to identify the presence of ABO antibodies. With a few exceptions, patients are expected to have the antithetical antibodies to ABO antigens they lack on their red blood cells. Forward typing is performed using known reagent antisera to detect ABO antigens on the patient's red blood cells. Antibody detection (screening) is performed using known reagent screening cells to detect clinically significant antibodies in the patient's serum or plasma. Phenotyping is performed using reagent antisera to phenotype donor red blood cells for clinically significant antigens.

As a student in a blood bank laboratory, you are tasked with determining the identification of an antibody as part of your practical exam. You are asked to use an enzyme treated red cell panel during the process of antibody identification. Which of the following antibodies is enhanced by enzyme treatment of red cells? - MN and Duffy antibodies - Rh, Lewis, and Kidd antibodies - Rh, A, B, and S antibodies - Duffy, A, and B antibodies

- Rh, Lewis, and Kidd antibodies The correct answer is Rh, Lewis, Kidd antibodies. Antibodies from these blood group systems will be enhanced (react more strongly) when tested against enzyme-treated reagent red blood cells. While antibodies in the Rh, Lewis, Kidd, and ABO blood group systems are enhanced when tested against red blood cells that have been enzyme-treated, antigens in the MNS and Duffy blood group systems are degraded when treated with enzymes, so antibodies against these antigens will be weaker or non-reactive when tested against enzyme-treated red blood cells. Therefore, the first choice is incorrect because it includes MN and Duffy antibodies; The third choice is incorrect because it includes S antibodies; The last choice is incorrect because it includes Duffy antibodies.

To prevent Rh alloimmunization in pregnancy between mother and fetus, it is recommended to initiate RhIG prophylaxis when? - Rh-positive pregnant females, postpartum. - Rh-negative pregnant females, antenatal in the first trimester. - Rh-negative pregnant females, antenatal in the third trimester. - Rh-positive pregnant females after delivery of an Rh-positive infant.

- Rh-negative pregnant females, antenatal in the third trimester. The clinical indications for RhIG administration are considered in cases where a Rh-negative pregnant female is giving birth to an Rh-positive infant, both antenatal and postpartum. It is recommended to administer RhIG prophylaxis early in the third trimester (antenatal). RhIG administration may be needed for a Rh-negative nonimmunized mother immediately after the delivery (postpartum) of an Rh-positive infant.

The term used to describe patients with absence of Rh antigens is: - Rhmod - Rhnull - Partial D - Del

- Rhnull In rare cases, individuals do not express any Rh antigens on their red blood cells. The term used to describe these individuals is Rhnull. Individuals that are Rhnull have mild compensated anemia, reticulocytosis, stomatocytosis, low hemoglobin and hematocrit, an increase in hemoglobin F, decreased serum haptoglobin, and in some cases, increased bilirubin. If a transfusion is needed, these patients would require blood from another Rhnull individual. Another set of individuals who are rare are those that have greatly reduced expression of Rh antigens due to suppression of the RH gene. Rhmod individuals have symptoms similar to those listed above, but in general the symptoms are less severe and not as significant clinically. Partial D is a mechanism in which the expression of D is weakened due to one or more D epitopes missing. These individuals are at risk for making an anti-D specific for the epitope that they are lacking. Expression of the other Rh antigens is normal in partial D. Del is a phenotype with very low D expression. Expression is so low in these patients that most anti-D will not detect the D antigen. Adsorption and elution methods can be used to detect the presence of D. Expression of the other Rh antigens is normal in Del.

Which of the following is an example of proper transfusion practices regarding fresh frozen plasma (FFP)? - Contains all labile coagulation factors except cryoprecipitate - Has a higher risk of transmitting hepatitis than whole blood - Should be transfused within 24 hours of thawing - ABO-compatible units are not required for transfusion purposes

- Should be transfused within 24 hours of thawing Fresh Frozen Plasma (FFP) should be thawed at 37°C and transfused within 24 hours when stored at 1 to 6°C. Indications for transfusion therapy include bleeding related to coagulation factor deficiency if specific concentrates are not appropriate, thrombotic thrombocytopenic purpura, and hemolytic uremic syndrome. FFP should not be used as a volume expander since there is a risk of transfusing transmitted diseases. FFP does not include all labile coagulation factors, and plasma should be ABO-compatible with the recipient's RBCs.

Donated red cell units contain which substance to stabilize the pH of the unit during storage? - Dextrose - Adenine - Citrate - Sodium biphosphate

- Sodium biphosphate Sodium biphosphate helps to stabilize the pH of the red cell unit during storage by preventing the pH from excessively becoming more acidic. Dextrose is used in ATP generation. Adenine supports ATP synthesis. Citrate chelates calcium to prevent coagulation.

Enzyme panel reactions cannot be used as the only source of rule-outs during antibody identification. Why is this? - Enzyme panels only detect warm autoantibodies - Enzyme panels only detect IgM antibodies - All antigens on the panel cells are destroyed by enzymes - Some antigens are destroyed and may not detect an antibody that is present

- Some antigens are destroyed and may not detect an antibody that is present Treating cells with enzymes will denature some of the antigens present on a panel. The antigens can no longer bind with the corresponding antibody once denatured. If antibodies to those denatured antigens are present, in the sample being tested, the panel will not detect the antibody. Enzyme panels are useful when it appears that multiple antibodies may be present, and the enzyme panel is a tool that may help separate the specificities and allow for identification. Enzyme treatment will enhance the antibody-antigen reactions of the Rh, Kidd, Lewis, P1, I and ABO systems. Enzyme treatment will destroy, or inactivate the antibody-antigen reactions, of the Duffy, MNS, and Xga systems.

Which of the following is the MOST IMPORTANT first step to take when a patient is transfused with un-crossmatched RBCs that turn out to be incompatible? - Order new blood specimens for the investigation. - Identify the antibody. - Perform an immediate spin crossmatch to rapidly determine incompatibility. - Stop any transfusion in progress.

- Stop any transfusion in progress. The correct answer is stop any transfusion in progress. Stopping any transfusion in progress is the most important first step since severity of hemolytic transfusion reactions partly depends on the volume of red cells transfused. Ordering of a new blood specimen should occur after the transfusion is stopped. Identifying the antibody will be necessary in order to determine the severity of the incompatibility and to be able to crossmatch compatible units. Performing an immediate spin crossmatch will only detect IgM (ABO) antibodies and should be performed as part of the transfusion reaction workup, but only once the transfusion is stopped.

What is the first step a transfusionist should take when a transfusion reaction is suspected? - Slow the transfusion and notify the physician. - Administer medication to stop the reaction. - Notify the laboratory of the reaction - Stop the transfusion, but keep the intravenous line open with saline.

- Stop the transfusion, but keep the intravenous line open with saline. The first critical step is to stop the transfusion immediately, but keep the patient's line open with saline. Once the transfusion is stopped, the tranfusionist notifies the physician. The transfusion needs to be stopped, no slowed, immediately. Notification of the laboratory or administration of medications, such as antihistamines for mild allergic transfusion reactions, are follow-up steps in the process of a transfusion reaction workup.

What is the MOST likely explanation for the following results? Anti-A = 1+ Anti-B = negative A1 Cells = 1+ B Cells = 4+ - Subgroup of A with anti-A1 - Group A with an acquired B antigen - Group O with hypogammaglobulinemia - Group AB with anti-A2 antibody

- Subgroup of A with anti-A1 This is an ABO discrepancy in which the forward ABO group appears as a group A, but the reverse grouping appears as a group O. Of the options listed only a subgroup of A with an anti-A1 would lead to those results. Subgroups of A often have weaker reactions in the forward due to less antigens on the cells. Additionally, due to the lack of some of the branched A antigens, that we see in A1 individuals, subgroups can make an anti-A1. The anti-A1 is causing the additional reaction in the reverse grouping. Group A with acquired B antigen would have a forward grouping that looks like AB and a reverse grouping that looks like A. Group O with hypogammaglobulinemia would have a forward grouping that looks like O and a reverse grouping that looks like AB (due to the lack of antibody production). Lastly, they AB with an anti-A2 does not exist since there is no anti-A2. Additionally, the patient did not type as AB in the forward.

A Bombay individual's blood specimen can be differentiated from a blood specimen of a group O person by which of the following? - Cells giving a negative reaction with anti-A,B - Testing with anti-H lectin (Ulex europaeus) - Reverse typing with A1 and B cells would be give different reactions - Testing with Dolichos biflorus

- Testing with anti-H lectin (Ulex europaeus) Testing with anti-H is the correct answer. Bombay individuals lack A, B, and H antigens and would test negative with anti-H lectin whereas an Type O individual has H antigens on their red cells and would test positive with anti-H lectin. Both a Bombay phenotype and a group O would test negative with anti-A,B as both blood types lack A and B antigens. Both a Bombay phenotype and a group O person possess anti-A and anti-B and would both test positive with A1 and B cells on the reverse typing. Testing with Dolichos biflorus (anti-A1 lectin) would not help differentiate a Bombay phenotype and a type O person as both blood types lack the A antigen on the surface of their red cells.

Which organism is MOST likely responsible for septic reactions associated with red blood cell transfusions? - Yersinia enterocolitica - Escherichia coli - Enterobacter species - Streptococcus species

- Yersinia enterocolitica The transfusion of small amounts of bacterially contaminated blood can be fatal or cause serious morbidity. Any contaminating bacteria in the donor unit that are unable to survive at 4oC die after several days of storage. Yersinia enterocolitica can thrive at 4oC and it can promote transfusion reactions. Gram positive and gram negative organisms have been linked to platelets stored at 20-24oC. These organisms include the bacteria Escherichia coli, Enterobacter species, and Streptococcus species.

What is the principle of the Kleihauer-Betke test? - The Kleihauer-Betke test capitalizes on the resistance of fetal hemoglobin to alkaline treatment. - The Kleihauer-Betke test capitalizes on the resistance of fetal hemoglobin to acid treatment. - The Kleihauer-Betke test capitalizes on the resistance of fetal hemoglobin to enzymatic treatment. - The Kleihauer-Betke test capitalizes on the resistance of fetal hemoglobin to radiation treatment.

- The Kleihauer-Betke test capitalizes on the resistance of fetal hemoglobin to acid treatment. The Kleihauer-Betke test is based on the principle that red cells containing adult hemoglobin are more susceptible to acid elution than those containing fetal hemoglobin. A thin smear of maternal blood is treated with acid, rinsed, and counterstained. The maternal red cells, predominately adult hemoglobin, appear as pale 'ghost' cells, and the fetal red cells, predominately fetal hemoglobin, are pink. The principle of the Kleihauer-Betke is not based upon fetal hemoglobin resistance to alkaline treatment, enzymatic treatment, or radiation treatment.

All of the following regarding Anti-A and Anti-B reagents used in forward typing for ABO typing are true EXCEPT? - They contain monoclonal antibodies. - The antibodies are highly specific. - The antibodies are IgG. - They produce an expected 3+ or 4+ reaction with the corresponding antigens.

- The antibodies are IgG. The correct answer is "The antibodies are IgG". This is the only statement about Anti-A and Anti-B reagents for forward typing that is NOT true. The antibodies in these reagents are IgM. All of the other choices are true of the reagents. The antibodies in the reagents are monoclonal, they are highly specific, and the reagents are designed to produce an expected 3+ or 4+ reaction with the corresponding antigens (Anti-A with A antigen and Anti-B with B antigen).

How are antibodies to the ABO blood group antigens unique? - Laboratory tests are available for their identification - The antibodies are naturally occurring to antigens that are absent from the red cell membrane - The antibodies are formed after the individual has been immunized - The antibodies are IgM

- The antibodies are naturally occurring to antigens that are absent from the red cell membrane The ABO blood group is the only blood group in which antibodies naturally appear to the antigens absent on the red cell membrane. Antibodies to other blood group systems are acquired after contact with the corresponding antigen. Laboratory tests are available and routinely performed to identify antibodies to ABO antigens and most other clinically significant antibodies (ex. Rh, Kidd, Kell, Duffy, and others). Individuals do not need to be immunized for ABO antibody production to start. Antibody production is naturally occurring, with production starting at birth. Most ABO antibodies are of the IgM class, but this is not unique to the ABO blood group. For example, anti-M and anti-N are usually IgM.

What would be considered a common characteristic of anti-Jka and anti-Jkb? - The immunoglobulin class is IgM. - Agglutination reactions are best observed by DAT. - The antibodies show dosage with Kidd antigens on red cells. - The antibodies are naturally occurring.

- The antibodies show dosage with Kidd antigens on red cells. Some common characteristics of anti-Jka and anti-Jkb include: the antibodies show dosage of Kidd antigens on red cells, the immunoglobulin class is IgG, agglutination reactions are best observed by IAT, and the antibodies are produced in response to antigen exposure through transfusion or pregnancy.

What must be true for the antiglobulin phase of the serologic crossmatch to be omitted (i.e., immediate spin crossmatch is done)? - The antibody screen must be negative and there is not history of detection of unexpected antibodies. - The patient has not been transfused within the past 24 hours. - The blood is needed for surgery. - There is a history of detection of unexpected antibodies but the current antibody screen is negative.

- The antibody screen must be negative and there is not history of detection of unexpected antibodies. The antiglobulin test may be omitted from the serological crossmatch if the patient's antibody screen is negative and there is no history of detection of unexpected antibodies. The transfusion history of the patient does not determine the type of crossmatch required for RBC transfusion. Patients scheduled for surgery should have a type and crossmatch complete prior to surgery. Patients with a history of antibodies, whether currently detectable or not, should have antiglobulin crossmatches.

Phenotype refers to: - The genes inherited from each parent - Opposing antigens produced by genes - The presence of two or more alleles at a locus - The expression of traits

- The expression of traits A phenotype refers to the traits that are expressed; routine blood bank testing detects phenotype. For example, a person may possess the A phenotype. A genotype is what is inherited from each parent. For example, a person who is the A phenotype may be AA or AO. Antithetical genes are opposing genes that are inherited at a given locus. Polymorphic genes will have two or more alleles at a locus.

A patient with a historical type of AB positive requires a routine type and screen test. You perform the ABO/Rh type using the gel methodology and note the results below. How would you interpret the results? - The back type is correct. The front type is incorrect and probably due to a manufacturing defect at the gel card production facility. - An elderly group O patient with a weak reaction in the back type due to compromised anti-A and anti-B production. - The front type is correct. The discrepancy in the back type can be ignored because it is not strong. - The front type is correct and the back type may due to cold agglutinins. You could prewarm the patient serum and repeat the back type to see if the discrepancy is resolved.

- The front type is correct and the back type may due to cold agglutinins. You could prewarm the patient serum and repeat the back type to see if the discrepancy is resolved. The patient forward types as group AB positive, and this is consistent with the historical type. The back type shows extra reactivity. Extra reactivity in the back type may be caused by alloantibodies, autoantibodies, or rouleaux. Warming the serum before repeating the back type is one method to help solve the discrepancy in the back type. Any discrepancies between the forward and back type should be investigated and resolved before finalizing ABO/D typing results and should not be reasoned away as problems with the testing system. These results show strong reactions in the forward type. These reactions along with the patient history indicate AB pos is most likely the correct type, so resolution steps should focus on the cause of the extra reactivity in the back type.

All of the following are major Rh antigens, EXCEPT? - D - d - C - c

- d There is no known d antigen. The d is used as a placeholder when designating genotypes, but it is not an actual antigen. Common antigens of the Rh blood group system include D, C, c, E and e.

In an emergency release, why do blood bankers seldom encounter patients who have experienced hemolytic transfusion reactions (HTR) from transfusion of uncrossmatched packed RBCs? Select the best response. - The incidence of unexpected red blood cell antibodies is relatively low. - They usually receive group O Rh-negative red blood cells; a hemolytic transfusion reaction will never occur if O Rh-negative red blood cells are transfused. - They hemorrhage so severely that incompatible donor red blood cells "bleed out" before a reaction occurs. - Some patients have cold-reactive antibodies that will not react at body temperature.

- The incidence of unexpected red blood cell antibodies is relatively low. Hemolytic transfusion reactions seldom occur due to the relatively low incidence (e.g., 1.64% has been cited in general patient populations) of unexpected clinically significant antibodies in random patients. In emergencies, the need for blood transfusion may exceed the need to complete compatibility testing, especially in cases with patients losing more than 20% of their own blood volume. Being transfused with group O, Rh-negative RBCs is irrelevant in cases where the recipient has an unexpected clinically significant antibody such as anti-K or anti-c. For testing purposes, it is important for pretransfusion samples to be collected prior to transfusion of uncrossmatched blood products. Pre-transfusion testing can be completed after the issuance of emergency release units. Incompatible red blood cells may "bleed out" as an adverse effect of blood transfusion. A hemolytic transfusion reaction may occur once the patient's antibody rebounds and destroys remaining antigen-positive donor red cells. me patients can have only cold-reactive antibodies that will not react at body temperature(37°C). However, this does not adequately explain the low number of reported HTRs in emergency release situations.

Which of the following statements is correct regarding blood bank adverse event reporting to the FDA? - All patient deaths while being transfused must be reported to the FDA, even when it has been confirmed that the death was not related to the transfusion. - When a transfusion reaction is the result of an error it must be reported to the FDA in writing. - A transfusion-related death must be reported to the FDA within 24 hours of the patient's death. - The initial notification to the FDA of a transfusion-related death must be made by fax, telephone, express mail, or electronically as soon as possible after the death is confirmed to be associated with the transfusion.

- The initial notification to the FDA of a transfusion-related death must be made by fax, telephone, express mail, or electronically as soon as possible after the death is confirmed to be associated with the transfusion. According to 21 CFR 606.170, a death must be reported to the FDA as soon as possible after the death is confirmed to be associated with the transfusion. The initial notification to the FDA of a transfusion-related death may be made by fax, telephone, express mail, or electronically. If it is confirmed that the transfusion is not the cause of their death, the death does not need to be reported to the FDA. Unless there is a death, it is not necessary to report the transfusion reaction to the FDA even if there was an error outside the blood bank. If the error was made outside the blood bank, it would not be reportable unless there was a transfusion related death.

The qualitative differences between A1 and A2 phenotypes includes all of the following EXCEPT: - The formation of anti-A1 in A subgroups. - The amount of transferase enzymes. - The length of the precursor oligosaccharide chains. - The lack of agglutination of patient red cells with anti-A reagent.

- The lack of agglutination of patient red cells with anti-A reagent. Qualitative differences for A1 and A2 phenotypes include the following: differences in the precursor oligosaccharide chains (in length and complexity of branching), small differences in transferase enzymes (decreased in A2 subgroup), and the formation of anti-A1 in the serum of A2 phenotype individuals. Both A1 and A2 patient red cells react with the anti-A reagent. Dolichos biflorus or anti-A1 lectin reagent is used to differentiate between A1 and A2 phenotypes. This lectin reagent agglutinates with A1 patient red cells but does NOT agglutinate with A2 patient red cells.

Why is it dangerous to transfuse a blood group O person with a unit of blood group A? - The patient will make antibodies to the type A blood. - The group A blood may become the prominent blood group. - The patient's Anti-O would destroy the donor's cells with severe consequences to the patient. - The patient's anti-A would destroy the donor's cells with severe consequences to the patient.

- The patient's anti-A would destroy the donor's cells with severe consequences to the patient. Group O individuals have naturally occurring anti-A, anti-B, and anti-A,B. These antibodies are "naturally occurring" because they are produced without being exposed to foreign red blood cells. Transfusing group A blood cells into a patient who is group O will result in a hemolytic transfusion reaction where the body would mount an immune response with anti-A against the foreign cells entering the body. The consequences of such a reaction can be very dangerous for the patient. The answer "The patient will make antibodies to the type A blood" is incorrect, because a person with blood type O already has anti-A and anti-B antibodies in his/her serum. Again, these are "naturally occurring" antibodies, the patient does not have to be exposed to type A, type B, or type AB blood to produce these antibodies. The group A red cells would be destroyed by the anti-A present in this group O patient so they would not change the patient's blood group. Lastly, there is no anti-O antibody. The O gene is an amorph, meaning is does not code for a transferase so there is no O antigen for an antibody to be made toward.

When giving a whole blood donation to a patient, what consideration must be made in regards to the ABO/Rh compatibility between the recipient and the donor? - The recipient and the donor ABO or Rh compatibilities are not a concern. - The recipient and donor ABO and Rh types must be compatible. - The recipient and donor ABO and Rh types must be identical. - The recipient and donor ABO types must be identical, but the Rh does not matter.

- The recipient and donor ABO and Rh types must be identical. Because whole blood donations contain all blood products, including plasma and red blood cells, the donor and recipient ABO and RH must be identical to prevent a transfusion reaction or development of Anti-D antibodies. ABO and Rh compatibilities are not typically a concern in platelet donations. However, donor and recipient ABO and Rh must be identical in whole blood donations since they contain all blood products. To not regard ABO and Rh compatibility would cause a transfusion reaction. Though ABO and Rh compatibility is safe for donated red blood cells, whole blood also contains plasma. Because of this, the ABO and Rh of donor and recipient must be identical to prevent a transfusion reaction. The Rh is a consideration because not matching a donor and recipient Rh may cause the recipient to develop anti-D following the transfusion. Like with red cell donations, transfusing Rh-positive blood into Rh-negative recipients should only be done in specific circumstances and as a last option.

Which one of the following statements about directed donations is TRUE? - They are safer than random donor units. - They will never cause graft-versus-host disease. - They do not cause logistical problems for blood banks. - They are often perceived by the recipient as safer than random donor units.

- They are often perceived by the recipient as safer than random donor units. The correct answer is that they are perceived by the recipient as safer than random donor units. Directed donations can sometimes be perceived as safer than non-directed units; however, this is often not the case. On occasion, the donors for directed units may not be completely forthcoming with information about their health status, which could potentially harm the recipient of the blood product unit. Therefore, directed donor units are not necessarily safer than random donor units. Since directed donations are often from family members, there is a high risk of graft-versus-host-disease. Directed donations to require accommodations on the part of the donor center and blood bank, as these units have all of the same testing as random donors and often require irradiation. These units also can only be used for the intended patient.

An elution is a technique that is used to release, concentrate, and purify antibodies that are bound to red blood cells. In preparing red cells for any elution method, one must be particularly careful to: - Leave a small amount of serum in the test system so complement will be present - Add albumin to decrease zeta potential - Pretreat the cells with enzymes - Thoroughly wash sensitized red cells

- Thoroughly wash sensitized red cells Elutions are commonly used when a patient has a positive direct antiglobulin test (DAT), indicating that there are antibodies coating the patient's red blood cells. Performing an elution releases the antibodies from the surface of the red blood cells, concentrates the antibodies, and purifies the antibodies. Elution methods include changing the temperature, changing the pH, and use of organic solvents. The most important step in an elution is the washing of the sensitized red blood cells. The washing removes immunoglobulins that are not bound to the cells. If washing is incomplete the unbound immunoglobulins will contaminate the final eluate and lead to a false-positive result. Leaving serum in the test serum will lead to contaminating immunoglobulins in the eluate interfering with the results (false-positive). Albumin can be used to reduce the zeta potential to enhance antigen-antibody binding. Enzymes are used to enhance expression of certain antigens (ABO, Rh, I, P, Kidd, Lewis) and destroy expression of other antigens (Duffy, MNS, Xga).

Which of the following clinical findings characterizes post-transfusion purpura (PTP)? - Increased hemoglobin - Pancytopenia - High ferritin levels - Thrombocytopenia

- Thrombocytopenia PTP is characterized by thrombocytopenia and bleeding (decreased hemoglobin). Platelet counts in PTP are typically less than 10,000/uL. Patients usually present with purpura, bleeding of the mucosal membrane, gastrointestinal, and/or urinary tract bleeding. Febrile reactions (or fever) have been observed in PTP. Pancytopenia is indicated in transfusion-associated graft-versus-host-disease (TA-GVHD). High ferritin levels have been noted in cases of iron overload. PTP, TA-GVHD, and iron overload are all categorized within delayed transfusion reactions.

An exchange transfusion has been ordered for a low birth weight infant. The physician has ordered irradiated Red Blood Cells for this purpose. Why is it necessary to irradiate the blood products for this patient? - To prevent alloimmunization of the patient - To prevent transfusion-associated graft-versus-host disease (TA-GVHD) - To kill bacteria and viruses present in the Red Blood Cells - To allow the cells to have a longer half-life

- To prevent transfusion-associated graft-versus-host disease (TA-GVHD) The correct answer is to prevent TA-GVHD. This occurs when donor lymphocytes from transfused blood engraft in the recipient and cause disease. Usually TA-GVHD occurs 3 to 30 days post transfusion with clinical features of fever, skin rash, hepatitis, diarrhea and pancytopenia. It is associated with a 90% mortality rate. Irradiation is indicated for patients who are at high-risk for TA-GVHD, including premature, low birth weight infants, directed donations from related donors, newborns with erythroblastosis fetalis, transplant recipients, and recipients with congenital immunodeficiencies.

Chloroquine diphosphate can be used in blood banking for which of the following methodologies? - To remove antibody bound to red cells so that cells can be further tested - To remove an specific antibody in serum or plasma - To remove ABO antigens from cells - To remove Rh antigens from cells

- To remove antibody bound to red cells so that cells can be further tested Chloroquine diphosphate (CDP) The most common use of chloroquine diphosphate in the blood bank laboratory is to remove IgG bound to red cells that were detected from a positive DAT. These treated RBCs can then be used for autologous adsorption and/or to determine the patient's RBC phenotype.

Which of the following transfusion reactions can a diagnosis be more firmly established by evaluating B-type natriuretic peptide (BNP) levels before and after transfusion? - Transfusion Associated Circulatory Overload (TACO) - Delayed Hemolytic Transfusion Reactions - Transfusion Associated Sepsis - Allergic Transfusion Reactions

- Transfusion Associated Circulatory Overload (TACO) Transfusion Associated Circulatory Overload (TACO) is difficult to distinguish from Transfusion Related Acute Lung Injury (TRALI). A post-transfusion to pretransfusion BNP ratio of 1.5 points is diagnostic of TACO. Delayed Hemolytic Transfusion Reactions testing includes the DAT, free plasma hemoglobin, hemoglobin, LDH, total and direct bilirubin, haptoglobin, free urine hemoglobin, and hemosiderin in urine. Transfusion Associated Sepsis testing includes blood cultures on the recipient and a gram stain and culture on the transfused component. Allergic transfusion reactions are diagnosed based on anaphylactic symptoms of the patient during transfusion of the component.

Acute intravascular hemolysis as the result of a blood transfusion is most often associated with which of the following causes? - Transfusion of ABO incompatible red blood cells - Allergic reaction - Passively transfused antibodies to HLA antigens - Transfusion-associated graft-versus-host disease

- Transfusion of ABO incompatible red blood cells Acute hemolytic transfusion reactions (AHTR) are most commonly due to ABO-incompatible blood being transfused to a recipient with naturally occurring ABO alloantibodies (anti-A, anti-B, anti A,B). This is different from passively transfused antibodies to HLA antigens. Typically, the interaction occurs between donor red blood cell antigens and preformed antibodies in the recipient. Hallmarks of intravascular hemolysis include hemoglobinemia and hemoglobinuria. Allergic reactions are not associated with AHTR because the etiology is either immune-mediated or nonimmune-mediated by origin. TA-GVHD falls under the category of a delayed hemolytic transfusion reaction.

Which of the following noninfectious complications of blood transfusion is prevented by the irradiation of blood components? - Anaphylactic reactions - Febrile non-hemolytic reactions - Transfusion-related acute lung injury (TRALI) - Transfusion-associated graft versus host disease (TA-GVHD)

- Transfusion-associated graft versus host disease (TA-GVHD) Irradiation prevents the proliferation of donor T lymphocytes in blood components. T lymphocytes in blood components may cause TA-GVHD in patients who are immunocompromised, who are receiving components from a blood relative, or who receive HLA-matched components. Washed components or components from IgA-deficient donors are indicated for patients at risk for anaphylactic reactions. The incidence of febrile non-hemolytic reactions has been reduced through the implementation of universal leukoreduction. One mitigation strategy to reduce the incidence of TRALI is to collect components from male donors, female donors who have never been pregnant, or female donors who have been tested since their last pregnancy and are negative for HLA antibodies.

HLA antibodies are responsible for which of the following transfusion reactions? - Allergic transfusion reactions - Transfusion-associated sepsis - Transfusion-associated circulatory overload - Transfusion-related acute lung injury (TRALI)

- Transfusion-related acute lung injury (TRALI) Antibodies to human leukocyte antigens (HLA) are responsible for transfusion-related acute lung injury (TRALI). The pathogenesis of this transfusion reaction is not fully understood, but there are two accepted mechanisms. The first involves antibodies to human leukocyte antigens or human neutrophil antigens transfused into a recipient. The antibodies bind and activate the recipient's leukocytes. The second mechanism involves a patient undergoing some event that primes their leukocytes. This includes a disease state, infection, or trauma). The patient is then transfused with a product that contains cytokines or anti-leukocyte antibodies, which then activate the already primed leukocytes. Both mechanisms cause leukocytes (especially neutrophils) to aggregate in the lungs. As a result, there is damage to the endothelium, which leads to an increase in pulmonary capillary permeability and noncardiogenic pulmonary edema. Allergic reactions are due to a recipient having an antibody (usually IgE) to a protein in the donor's plasma. They can also be caused by donor antibodies to a protein present in the recipient's plasma. Transfusion-associated sepsis is caused by bacterial contamination of a transfused product. Transfusion-associated circulatory overload is caused by the inability of a patient's circulatory system to handle the additional workload from the transfused product. It occurs when the volume or rate of transfusion is too high.

Following the treatment of an IgG molecule with papain, which of the following will remain? - Two Fab fragments each with a light chain and a partial heavy chain attached with a disulfide bond - Four separate light chains and two separate heavy chains - One unit that consist of a two partial heavy chains, two light chains all attached with a disulfide bond - Eight units, two complete light chains, and two heavy chains split in half

- Two Fab fragments each with a light chain and a partial heavy chain attached with a disulfide bond Digestion with papain will cut above the disulfide bond that holds the heavy chains together, leaving two units, each with a partial heavy chain and a light chain held together with a disulfide bond. Digestion with urea and mercaptoethanol will remove all disulfide bonds leaving free units of light and heavy chains. Digestion with pepsin will cut below the disulfide bond, leaving one unit of two partial heavy chains and two light chains all attached with a disulfide bond. There is no digestive enzyme that results in eight units.

Kernicterus can cause brain damage in newborns suffering from severe HDFN. This is due to a buildup of: - Unconjugated bilirubin - Hematocrit - Haptoglobin - Hemoglobin

- Unconjugated bilirubin Hemolytic disease of the fetus and newborn leads to the destruction of fetal red blood cells caused by a maternal antibody (IgG) that is able to cross the placenta. During pregnancy, the unconjugated or indirect bilirubin that is released from the red cell destruction is able to cross the placental where it is conjugated by the maternal liver and excreted by the mother. After birth, the buildup of bilirubin becomes a major problem for the baby because the baby's liver is unable to conjugate the indirect bilirubin efficiently (and the maternal liver is no longer there), and therefore the bilirubin is not excreted. The unconjugated bilirubin can reach toxic levels (usually greater than 18-20 mg/dL) and cause damage to the infant's brain. If this is not treated, permanent damage can occur. This is dangerously termed kernicterus. Kernicterus is not due to an increase in hematocrit, haptoglobin, or hemoglobin.

All of the following are appropriate indications for the use of fresh frozen plasma (FFP) EXCEPT? - Volume expansion - Severe bleeding in the presence of significantly elevated PT secondary to vitamin K deficiency - Replacement component after plasma exchange in patients with TTP or HUS - Dilutional coagulopathy with significant active bleeding, and PT and PTT twice normal

- Volume expansion Since each unit of fresh frozen plasma (FFP) carries with it the risk of transmitting blood-borne pathogens, and other products (such as normal saline or albumin) which do not carry this risk are available, FFP should not be used as a volume expander. Elevated PT or PTT results, with bleeding or coagulopathy, would require the replacement of clotting proteins, and FFP would be indicated. FFP would be a necessary replacement component in cases of plasma exchange.

An O positive patient has no reactions at immediate spin but both screen cells are positive and all antibody panel cells are reacting 1+ at AHG. The auto control is 1+. What would you suspect to be the cause? - Cold autoantibody - Warm autoantibody - Anti-Lea - Anti-K

- Warm autoantibody There is no reaction at the immediate spin phase, so the cold autoantibody can be eliminated. Reactivity is occurring at AHG with all panel cells, and the auto control is positive, which can indicate a warm autoantibody. Adsorption and elution techniques may be beneficial to determine if other clinically significant antibodies are present or to help identify the warm autoantibody. Reactions due to anti-Lea would likely be at the immediate spin phase and would not occur on all panel cells. Reactions due to anti-K would likely occur at AHG but would not occur on all panel cells.

Which of the following is the most common type of autoimmune hemolytic anemia? - Warm autoimmune hemolytic anemia. - Cold agglutinin disease. - Paroxysmal cold hemoglobinuria. - Drug-induced immune hemolytic anemia.

- Warm autoimmune hemolytic anemia. Warm autoimmune hemolytic anemia (WAIHA) involves autoantibodies that react best at 37 degrees Celsius. Most cases of true autoimmune hemolytic anemia are due to WAIHA. In fact WAIHA represents approximately 70% of the cases of autoimmune hemolytic anemias. Some warm autoantibodies are harmless but others can cause severe anemia that results in the patient requiring a transfusion. WAIHA may be occur after infection, surgery, trauma, pregnancy, or may be idiopathic. Cold agglutinin disease is due to cold autoantibodies which account for approximately 18% of autoimmune hemolytic anemias. Cold agglutinin disease is due to an autoantibody (IgM class) that reacts best at 4 degrees Celsius but can also react between 25-30 degrees Celsius. These antibodies are usually able to activate complement. Paroxysmal Cold Hemoglobinuria (PCH) is the least common of the autoimmune hemolytic anemias as it is only responsible for 1-2% of autoimmune hemolytic anemias. PCH is due to a biphasic IgG antibody (also called Donath-Landsteiner antibody) that binds at temperatures below body temperature and activates complement at 37 degrees Celsius. Drug-induced immune hemolytic anemia is due to unwanted side effects of therapeutic drugs. It is rare but can result in the destruction of red blood cells, white blood cells, and platelets.

A patient who demonstrates a history of an allergic reaction from red blood cell transfusions will benefit from receiving which red cell component? - Frozen red blood cells - Washed red blood cells - Irradiated red blood cells - Leukocyte-reduced red blood cells

- Washed red blood cells Patients who demonstrate an allergic or anaphylactic response following transfusion with red cells typically do so against plasma proteins present in the unit. Washing the red cells will remove the excess plasma proteins to decrease or prevent the reaction. Freezing red cells should only be performed to maintain units with rare antigen attributes or to increase the shelf life of autologous units. This practice does not change the concentration of plasma proteins, which are responsible for causing the allergic or anaphylactic reaction. Irradiating red blood cells prevents the donor T lymphocytes from multiplying, which can cause transfusion-associated graft-vs-host disease. This does not, however, prevent most allergic responses. Leukocyte-reduction of red blood cells can prevent febrile reactions. However, the filter used for leukocyte-reduction is not able to filter out the plasma proteins that can cause allergic and anaphylactic responses.

What is the MOST likely cause of the ABO discrepancy when the following results were obtained from a first-time 29-year old, blood donor? Forward Group Anti-A = Negative Anti-B= Negative Reverse Group A1 Cells = Negative B Cells = 3+ - Loss of antigen due to disease - Acquired B - Low immunoglobulin levels - Weak subgroup of A

- Weak subgroup of A The ABO grouping results seen above demonstrate a forward grouping that looks like group O and a reverse grouping that looks like group A. The patient is healthy due to be eligible to donate blood. The most likely cause for these results is the donor being a weak subgroup of A. Subgroups of A have fewer antigenic sites on the red cells and will therefore react weaker with reagents in the forward grouping (as seen above). To determine if A is present on these donor cells, adsorption and elution studies can be performed. The loss of antigen due to a disease state could cause the results seen above. Diseases such as leukemia have been associated with a decrease in antigen expression. Acquired B would cause an unexpected additional reaction with the anti-B in the forward. This is associated with diseases of the digestive tract and is due to enzymes from bacteria modifying the A antigen so that it now reacts with anti-B. Lastly, low immunoglobulin levels are unlikely due to the strong 3+ reaction seen with the B cells in the reverse grouping and the lack of a disease state or advanced age in the donor.

If Jka is showing dosage, how might reactions on an antibody panel appear? - Weaker if homozygous for Jka - Stronger if heterozygous for Jka and Jkb - Weaker if heterozygous for Jka and Jkb - Both heterozygous and homozygous reactions would always be of equal strength

- Weaker if heterozygous for Jka and Jkb The strength of reaction can be due to the number of antigens present on the red cells that can bind with the antibody present. Inheritance of antigens can be in the homozygous or heterozygous state. -----> If the antigen is in the homozygous state, there is a double dose of the antigen present on the red cell. For antibody reactions showing dosage, antigen-antibody reactions will be stronger if in the homozygous state since there is more antigen to bind with the antibody. The antigen-antibody reactions will be weaker if in the heterozygous state since there is less antigen to bind with the antibody.

Transfusion of which blood product is most likely to cause circulatory overload in patients? - Platelets - Fresh frozen plasma - Red blood cells - Whole blood

- Whole blood Many patients only require a specific therapy from blood products, such as an increase in oxygen-carrying capability or coagulation factors. To give these patients whole blood would cause a large increase in blood volume, potentially leading to transfusion-associated circulatory overload. Platelets contain very little plasma or volume. Transfusion of platelets does not create a circulatory overload. Fresh frozen plasma can cause circulatory overload if the recipient receives a high volume or high rate of infusion or if the patient has an underlying condition affecting the heart or lungs. However, fresh frozen plasma does not contain as great of a volume as whole blood and is generally safer to use as long as it is properly transfused. Red blood cells can cause transfusion-associated circulatory overload. However, since the majority of plasma has been removed from these units, the likelihood of transfusion-associated circulatory overload is typically low unless the patient receives a large volume or high rate of infusion or if the patient has an underlying condition that affects the heart or lungs.

When a unit of packed RBC's is split using the open system, each portion of the unit must be issued: - Within 24 hours - Within 48 hours - Within 30 days - By the original expiration date

- Within 24 hours The correct answer is within 24 hours. If a unit is entered without use of a sterile connection device (open system) it must be used within 24 hours of entry. Closed systems retain the same expiration date as the original whole blood unit.

Generally speaking, infant RBCs demonstrate the presence of the ____ antigen, which gradually decreases as one ages. Conversely, the ____ phenotype is not expressed at birth, but the amount of this antigen increases as one ages. - M; N - K; k - i; I - M; K

- i; I From birth onwards - the "i" antigen slowly decreases on the RBC surface, while the "I" antigen increases reciprocally. It's a unique characteristic of this particular pair, with no other pair of common blood bank relevant antigens demonstrating such a trait. In practice, while auto anti-i is rarely seen, when suspected, one could simply react the patient's serum with cord RBCs, expecting to see a strong reaction. Meanwhile, reacting the patient's serum with adult RBCs would yield a weak or no reaction. Antigens in the MNS and Kell systems are present at birth. The number of antigens expressed on red cells within these systems does not vary based on age.

What is the most frequent genotype among Rho (D) negative persons? - r'r - r'r" - rr - r"r

- rr The most frequent genotype among Rh-negative individuals is rr. The genotype symbolized a lack of the D (Rh) gene. This is shown in 15% of the white population and 7% of the black population. The genotypes r'r, r'r", and r"r are found in < 1% of the white and black population.