blood bank SUCCESS questions

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D. Platelet count/uL X 1000 uL/mL X Volume (mL) = Total count in component (Total count in PRP/ Total count in whole blood) X100 = % yield from whole blood (Total count in platelet concentrate/ Total count in PRP) X100 = % yield from PRP In the example above, the total count in PRP would be: 300,000 X 1000 X 250 = 7.5 X 10^ 10 platelets The total count in whole blood is 200,000 X 1000 X 450 mL = 9 X 10^ 10 platelets The percent yield from whole blood is: (7.5 X 10^10/ 9 X 10^10) X100 = 83%

A centrifuge used for platelet preparation has been returned after major repair. A unit of whole blood (450 mL; platelet count 200,000/uL) is selected for calibration of platelet production. The platelet-rich plasma (PRP) contains 250 mL with a platelet count of 300,000/uL. The final platelet concentrate prepared from the PRP contains 50 mL with a platelet count of 900,000/uL. 18. What is the percent yield of platelets in the PRP from this unit? A. 33% B. 45% C. 66% D. 83

D. Platelet count/uL X 1000 uL/mL X Volume (mL) = Total count in component (Total count in PRP/ Total count in whole blood) X100 = % yield from whole blood (Total count in platelet concentrate/ Total count in PRP) X100 = % yield from PRP

A centrifuge used for platelet preparation has been returned after major repair. A unit of whole blood (450 mL; platelet count 200,000/uL) is selected for calibration of platelet production. The platelet-rich plasma (PRP) contains 250 mL with a platelet count of 300,000/uL. The final platelet concentrate prepared from the PRP contains 50 mL with a platelet count of 900,000/uL. 19. What is the percent yield of platelets in the final product from the PRP? A. 30% B. 45% C. 50% D. 60%

B.

A centrifuge used for platelet preparation has been returned after major repair. A unit of whole blood (450 mL; platelet count 200,000/uL) is selected for calibration of platelet production. The platelet-rich plasma (PRP) contains 250 mL with a platelet count of 300,000/uL. The final platelet concentrate prepared from the PRP contains 50 mL with a platelet count of 900,000/uL. 20. Does this product meet AABB Standards for platelet concentrate production? A. Yes B. No; the count on the final product is too low. C. No; the percentage recovery in the PRP is too low. D. Data are insufficient to calculate.

B.

A centrifuge used for platelet preparation has been returned after major repair. A unit of whole blood (450 mL; platelet count 200,000/uL) is selected for calibration of platelet production. The platelet-rich plasma (PRP) contains 250 mL with a platelet count of 300,000/uL. The final platelet concentrate prepared from the PRP contains 50 mL with a platelet count of 900,000/uL. 21. The final product was prepared with a PRP spin time of 2 minutes at 2500 rpm. To increase the percent platelet yield in the final product, one would A. Increase the time and/or rpm for the first spin B. Increase the time and/or rpm for the second spin C. Decrease the time and/or rpm for the first spin D. Decrease the time and/or rpm for the second spin

C. (Post (F VIII lU/mL X volume mL)/ Pre (F VIII lU/mL X volume mL)) X100 = % Factor VIII recovery In this instance, ((9 lU/mL X 10 mL)/ (1 IU/mL X 250 mL)) X100 = 36% Factor VIII recovery

A satellite bag containing 250 ml of fresh plasma is selected for quality control of cryoprecipitate production. Cryoprecipitate is prepared according to standard operating procedures. The final product has a total volume of 10 ml. The factor VIII assays are 1 IU/mL before and 9 IU/mL after preparation 16. What is the percent yield of factor VIII in the final cryoprecipitate? A. 11% B. 25% C. 36% D. 80%

A.

A satellite bag containing 250 ml of fresh plasma is selected for quality control of cryoprecipitate production. Cryoprecipitate is prepared according to standard operating procedures. The final product has a total volume of 10 ml. The factor VIII assays are 1 IU/mL before and 9 IU/mL after preparation 17. Does this product meet AABB Standards for cryoprecipitate production? A. Yes B. No; the percent recovery is too low. C. No; the final factor VIII level is too low. D. Data are insufficient to calculate.

C. Some potential donors are rejected to protect the recipient, and others are rejected to protect themselves. In this case, the woman meets the criteria except that her hematocrit is too low, and the loss of a unit of blood may have a detrimental effect on her. The minimum acceptable hematocrit is 38%

1. A woman wants to donate blood. Her physical examination reveals the following: weight—110 Ib, pulse—73 bpm, blood pressure—125/75 mm Hg, hematocrit—35%. Which of the following exclusions applies to the prospective donor? A. Pulse too high B. Weight too low C. Hematocrit too low D. Blood pressure too low

B. It is acceptable according to FDA and AABB Standards to screen donors for infectious diseases in pools of 16 to 24 donor sera. If a donor pool is positive for HCV, all individual donors making up the pool are tested individually using the same nucleic acid test (NAT) to find the positive donor. When that donor is identified, s/he is excluded from donating henceforth and all components from that donation are retrieved and destroyed.

10. A pooled sera product from 16 donors has a repeatedly positive nucleic acid test (NAT) for HCV. The next action that should be taken is to A. Permanently exclude all the donors in the pool B. Test each donor in the pool for HCV C. Label all the donors as HCV positive D. Confirm the positive using recombinant immunoblot assay (RIBA)

B. Solid-phase red cell adherence assays, the gel test, and affinity column technology are all third-generation antibody detection methods. They have equal or greater sensitivity for clinically significant antibodies than first- and second-generation techniques. In general, they have the following advantages: less hands-on time, smaller sample size, improved safety, and stable endpoints, and they can be automated. In the gel test, the antiglobulin test does not require washing or the addition of IgG coated cells, because unbound globulins are trapped in the viscous barrier at the top of the gel column. Upon centrifugation, the anti-IgG in the column traps red cells that have been coated with IgG during the incubation period. In affinity column technology, the viscous barrier traps unbound IgG, but Staphylococcus aureus derived protein A and protein G are in the column instead of anti-IgG and react with the Fc portion of IgG-coated red cells. The other two techniques, solid-phase red cell adherence and polyethylene glycol, require a washing step.

100. The antiglobulin test does not require washing or the addition of IgG-coated cells in which of the following antibody detection methods? A. Solid-phase red cell adherence assays B. Gel test C. Affinity column technology D. Polyethylene glycol (PEG) technique

D. The three antibodies, anti-Pj, anti-Lea, and anti-I, are most often non-red-cell-stimulated IgM antibodies. All of these antibodies can also, however, be stimulated by exposure to red blood cells carrying the corresponding antigen. Each of the other answers has at least one antibody that will be formed only due to exposure, either through transfusion or pregnancy, to the corresponding red cell antigen.

101. Which set of antibodies could you possibly find in a patient with no history of transfusion or pregnancy? A. Anti-I, anti-s, anti-P1 B. Anti-Leb, anti-A1 anti-D C. Anti-M, anti-c, anti-B D. Anti-P1 anti-Lea, anti-I

B. Lymphocytotoxicity testing is performed by adding patient mononuclear leukocytes to wells containing sera that have antibodies to various HLA antigens and then adding guinea pig complement and indicator dye. The cells that take up the dye have had their cell membranes perforated by the action of the antigen-antibody reaction and complement, indicating that they carry the HLA antigen corresponding to the antibody in the well. Although the antibodies to Bg system antigens are antibodies to HLA antigens, the Bg terminology is only used for the remnant HLA antigens found on RBCs. The Wright system and JMH antigens are RBC antigens and are not related to the HLA system.

102. Lymphocytotoxicity testing can be used to detect the presence of antibodies to A. Wr^a and Wr^b B. HLA antigens C. Bg^a,Bg^b,and Bg^c D. JMH antigen

A. Mixed-field agglutination refers to an agglutination pattern where there are two distinct cell populations, one agglutinated and one not. The appearance is clumps of cells among many unagglutinated cells. In a delayed hemolytic transfusion reaction, surviving donor cells will be coated with patient antibody and the patient's own cells will not, yielding a mixed-field DAT result. Other examples of mixed-field agglutination are seen in patients who have been transfused with blood of another ABO group, in patients with Lutheran antibodies, and in Dnegative mothers with D-positive infants where there was a large fetomaternal bleed. Also, A3 subgroup RBCs may demonstrate a mixed-field reaction with anti-A.

103. In which of the following instances may mixed-field (mf) agglutination be observed? A. Direct antiglobulin test (DAT) result of patient undergoing delayed hemolytic transfusion reaction B. Indirect antiglobulin test (IAT) result of patient who has anti-Lea C. DAT result of patient on high doses of a-methyldopa D. Typing result with anti-A of patient who is A2 subgroup

D. In the United States, the weak D test is performed routinely when a donor appeal's to be Rlinegative, and all weak D donor units are labeled Rh-positive. Weak D units are much less immunogenic than normal D units. In many countries, neither donors nor recipients are tested for weak D.

34. Which of the following weak D donor units should be labeled Rh-positive? A. Weak D due to transmissible genes B. Weak D as position effect C. Weak partial D D. All the above

D. The first antibody to become detectable in a primary immune response to a foreign blood group antigen is IgM followed by IgG, usually detectable from less than a week to several months after immunization. After secondary exposure to the same antigen, the antibody titer usually increases rapidly within several days. Antibodies are produced by plasma cells. The antibody produced by the plasma cells in the secondary response is IgG. Plasma cells are the terminal differentiation of the B lymphocytes. Differentiation occurs in the presence of certain cytokines when B lymphocytes are stimulated by "seeing" the antigen that corresponds to the binding site of the immunoglobulin on the B cell surface.

104. The antibody produced during the secondary response to a foreign antigen is usually A. IgM B. A product of T lymphocytes C. Produced a month or more after the second stimulus D. Present at a higher titer than after a primary response

D. All the conditions listed affect the agglutination of A and B cells in serum grouping. The gamma-globulin fraction of the serum contains the immunoglobulins. When it is reduced, there will be fewer molecules of blood group antibodies, leading to weakened or negative reactions. Both cold autoagglutinins and cold reactive IgM alloantibodies, which will react at room temperature (such as anti-M), may agglutinate the cells used because of the presence of the corresponding antigen on the group A and/or B red blood cells. Cold auto- and alloantibodies are the most common causes of ABO discrepancies.

105. In which situation(s) may the ABO serum grouping not be valid? A. The patient has hypogammaglobulinemia. B. IgM alloantibodies are present. C. Cold autoantibodies are present. D. All the above

C. Blood for intrauterine transfusion should be group O, D-negative (because the fetus's blood group is unknown) and negative for the antigen corresponding to any other IgG antibody in the maternal serum. It should be recently drawn and administered as RBC (Hct 75-85%) to minimize the chance of volume overload. It should be irradiated, CMV safe, and known to lack hemoglobin S.

106. A group A, D-negative obstetric patient with anti-D (titer 256) is carrying a fetus who needs an intrauterine transfusion. Which of the following units should be chosen? A. Group A, D-negative RBC B. Group A, D-negative whole blood C. Group O, D-negative RBC D. Group O, D-negative whole blood

A. Anti-Jka is an IgG antibody and is nearly always detected in the antiglobulin phase. Rarely, it can be detected at the 37°C phase of testing. Anti-M, anti-Pj, and anti-I are generally IgM antibodies and react at room temperature and below by direct agglutination.

107. Which of the following is generally detected at the antiglobulin phase of testing? A. Anti-Jka B. Anti-M C. Anti-P1 D. Anti-I

D. Lewis system antibodies are generally IgM. Antibodies in the Rh, Duffy, and Kell systems are generally IgG. There may be rare IgM exceptions

108. Which of the blood group systems is associated with antibodies that are generally IgM? A. Rh B. Duffy C. Kell D. Lewis

B. Bg antibodies react with the red blood cell equivalents of HLA antigens. Bga corresponds with HLA-B7, Bgb with HLA-B17, and Bgc with HLA-A28. These antibodies can be frustrating in that few panel cells will react and the Bg type of panel cells is often not listed.

109. Some antigens that are primarily found on white blood cells can occur on erythrocytes. Which of the following are the red blood cell equivalents of human leukocyte antigens (HLAs)? A. Lea,Leb B. Bga,Bgb,Bgc C. Kpa, Kpb, Kpc D. Doa,Dob

D. Cryoprecipitate provides the only known concentrated source of fibronectin, useful in the phagocytic removal of bacteria and aggregates by the reticuloendothelial system. It also contains factors VIILC, VHLvW, and XIII. Antithrombin III (AT III), necessary to prevent a thromboembolic disorder, is depleted in DIG and liver disease. Transfusion sources of AT III are fresh-frozen plasma (FFP) and commercial concentrates, but AT III is not present in cryoprecipitate.

11. Although Cryoprecipitate has primarily been used for treatment of hypofibrinogenemia and hemophilia A, it contains other blood proteins useful in the treatment of coagulopathies. Which of the following is not found in Cryoprecipitate? A. Fibronectin B. Factor XIII C. Factor VIILvW D. Antithrombin III

D. FFP contains all the plasma clotting factors. FFP's primary use is for patients with clotting factor deficiencies for which no concentrate is available and patients who present multiple factor deficiencies such as in liver disease. Platelets are cellular elements, not a plasma clotting factor, and they must be maintained at 20-24°C with continuous gentle agitation to maintain their viability.

12. Even though it is properly collected and stored, which of the following will freshfrozen plasma (FFP) not provide? A. Factor V B. FactorVIII C. Factor IX D. Platelets

C. The A ABB Standards require that when a patient is likely at risk for graft-versus-host disease (GVHD), all cellular blood components must be irradiated before transfusion. This includes components for patients who are immunodeficient or immunoincompetent, such as a patient on immunosuppressive therapy and a fetus who receives intrauterine transfusion. Irradiation of RBCs for exchange transfusion is not required by AABB Standards, although many hospital transfusion services do so. Immunocompetent individuals require irradiated components if they are to receive cellular components from someone who may be homozygous for a shared HLA haplotype, such as a blood relative or an HLA-matched donor. Gamma irradiation of cellular components is the only way to prevent transfusion-associated GVHD that occurs when immunocompetent donor T cells survive in the patient's circulation and mount an immune response against the host cells. A minimum of 25 Gy delivered to the midplane of the container and at least 15 Gy to all other areas will prevent GVHD.

13. Blood needs to be prepared for intrauterine transfusion of a fetus with severe HDN. The red blood cell unit selected is compatible with the mother's serum and has been leuko-depleted. An additional step that must be taken before transfusion is to A. Add pooled platelets and fresh-frozen plasma B. Check that the RBC group is consistent with the father's C. Irradiate the RBCs before infusion D. Test the RBC unit with the neonate's eluate

B. Previous ABO and Rh records of patients must be retained for 10 years and be immediately available for 12 months as a check to confirm the identity of the current pretransfusion sample. Records of unexpected antibodies identified in the serum of intended recipients and of serious adverse reactions to blood components must be retained indefinitely. Consulting records may prevent a delayed hemolytic transfusion reaction when the antibody is no longer demonstrable.

33. Previous records of patients' ABO and Rh types must be immediately available for comparison with current test results A. For 6 months B. For 12 months C. For 10 years D. Indefinitely

133. B. The patient's positive antibody screening test is consistent with an anti-K, and this is what was identified in the antibody identification. Three K antigen-positive and three K antigennegative cells were tested and reacted appropriately. The antibody identification could have been misinterpreted, but it seems unlikely. The panel must have been read at the AHG phase of testing, because most examples of anti-K do not react at any other phase of testing. Positive and negative control cells (K+k+ and K-k+) should be tested with the anti-K at the same time as the patient's cells to be certain of the specificity of the anti-K antiserum. There is no indication that this has been done, and the patient's phenotype should not be K+. If the patient had circulating K+ donor cells, the K typing would have shown a mixed-field reaction, which has not been indicated.

133. The following results were obtained upon testing a specimen of a patient, being admitted after a car accident, who had no recent history of transfusion or medical problems. ABO group: A Rh type: D-positive Antibody screening test: Positive, one screening cell only Direct antiglobulin test: Negative -Antibody identification: Anti-K identified; 3 K+ cells that reacted with the patient serum and 3 Kcells that did not react with the patient serum were on the panel. Patient's cell phenotyping: K+ What is the most likely cause of the discrepant results? A. Failure to read panel at antiglobulin phase B. Failure to use positive and negative controls with anti-K C. Panel cell reactions interpreted incorrectly D. Patient has circulating donor cells that areK+

134. B. Although there are many potential sources for error in performing an indirect antiglobulin test, the most common error leading to a false negative reaction is the failure to wash the red blood cells adequately before the addition of AHG reagent. Traces of free human globulin can neutralize the AHG reagent. Red cells known to be coated with IgG antibody (Coombs' control cells, check cells) are added to all negative tests. Agglutination of these control cells confirms that AHG was present in the system and that proper washing procedures were performed.

134. False negative results at the antiglobulin phase of an antibody screening test are most likely due to A. Excessive washing of the red cells B. Inadequate washing of the red cells C. Warm autoantibody present in the patient's serum D. Failure to allow the blood to clot properly

A. The limiting criterion for in vitro storage of blood is the survival in the recipient of at least 75% of the transfused red cells for at least 24 hours after transfusion. Additional adenine in an anticoagulant-preservative formulation provides a substrate for the continued generation of ATP in vitro. The overall effect is improved viability.

14. The addition of adenine in an anticoagulant-preservative formulation aids in A. Maintaining ATP levels for red cell viability B. Maintaining platelet function in stored blood C. Reducing the plasma K+ levels during storage D. Maintaining 2,3-BPG levels for oxygen release to the tissues

D. Donor blood may not be labeled according to test results obtained from previous donations. Several segments removed from the donor unit will provide sufficient sample for all required testing but will limit the number of segments available for crossmatching. After centrifugation, the plasma may be removed from the segments and clotted with calcium chloride or a similar commercial product for use in test procedures requiring serum. Alternatively, institutions with sterile connecting devices may attach a small bag and remove an aliquot sufficient for testing.

15. The pilot tubes for donor unit #3276 break in the centrifuge. You should A. Label the blood using the donor's previous records B. Discard the unit because processing procedures cannot be performed C. Discard the red cells and salvage the plasma for fractionation D. Remove sufficient segments to complete donor processing procedures

C. Donors are allowed to donate no more than 10.5 mL/kg of their body weight. This amount includes the samples used for testing drawn at the time of collection. The calculation for a 95Ib donor is: 95 Ib divided by 2.2 Ib/kg = 43.2kg.... 43.2 kg X 10.5 mL/kg = 453.6 mL If less than 300 mL is to be collected, the anticoagulant must be reduced proportionately.

2. A potential donor has no exclusions, but she weighs only 95 pounds. What is the allowable amount of blood (including samples) that can be drawn? A. 367 mL B. 378 mL C. 454 mL D. 473 mL

B. A low red blood cell concentration of 2,3-BPG increases red cell affinity for O2, causing less O2 to be released to the tissues. As blood is stored, 2,3BPG levels fall. Once the blood is transfused, red cells regenerate 2,3-BPG and ATP, which are fully restored in about 24 hours. Other metabolic changes that occur as blood is stored are an increase in plasma K+ as red cells leak K+, an increase in plasma hemoglobin, and a decrease in ATP.

22. When 2,3-BPG levels drop in stored blood, which of the following occurs as a result? A. Red blood cell K+ increases. B. Red blood cell ability to release O2 decreases. C. Plasma hemoglobin is stabilized. D. ATP synthesis increases.

D. Autologous blood should not be drawn later than 72 hours prior to surgery. The reason is to allow time for adequate volume repletion. However, the medical director may decrease this time if the patient's condition warrants it.

23. The last unit of autologous blood for an elective surgery patient should be collected no later than__________ hours before surgery. A. 24 B. 36 C. 48 D. 72

B. Preoperative autologous donation is commonly done for orthopedic surgery, radical prostatectomy, and open heart surgery. Patients with uncompensated anemia and hemoglobin levels below 11.0 g/dL are unable to donate because they do not have sufficient red blood cells to maintain oxygen-carrying capacity after the donation. Because it is difficult to find donors for patients with multiple antibodies or an antibody to a high-incidence antigen, these individuals, if anemic, may be given supplemental iron and allowed to donate once their hemoglobin levels are above 11.0 g/dL. Their cells can also be frozen for later use.

24. For which of the following patients would autologous donation not be advisable? A. Patients with an antibody against a high-incidence antigen B. Patients with uncompensated anemia C. Open heart surgery patients D. Patients with multiple antibodies

C. Both Hepatitis B virus (HBV) and hepatitis C virus (HCV) are transfusion transmitted. However, only HCV is associated with hepatocellular carcinoma and cirrhosis of the liver in many of the chronically infected. Because nucleic acid testing for HCV is done on all donor samples, there is only a small risk (<1 in 2,000,000) of transmission from tested donors. The acute phase of the disease is frequently asymptomatic, but most of these patients become chronic carriers, with 70-80% having persistent infections. About 10% of those chronically infected eventually develop cirrhosis and/or hepatic carcinoma.

25. It is generally asymptomatic but has a very high carrier rate (70-80% have chronic infections). About 10% of the carriers develop cirrhosis or hepatocellular carcinoma. These statements are most typical of which of the following transfusion-transmitted infections? A. HAV B. HBV C. HCV D. HEV

B. Red blood cells continue to metabolize, albeit at a slower rate, during storage at 1-6°C. Decreased ATP levels result in loss of RBC viability. Plasma hemoglobin, ammonia, and K+ levels increase, whereas plasma Na+ and pH and 2,3-BPG levels decrease. These biochemical changes are collectively referred to as the "storage lesion" of blood.

26. Biochemical changes occur during the shelf life of stored blood. Which of the following is a result of this "storage lesion"? A. Increase in pH B. Increase in plasma K+ C. Increase in plasma Na+ D. Decrease in plasma hemoglobin

C. Because the patient received eight units of blood and none of the donors has been implicated in other cases of hepatitis, none of these donors would be deferred. The donor center should be immediately notified so it can enter in each donor's record that s/he has been implicated in a case of transfusion-transmitted hepatitis. After a second implication, the donor would be indefinitely deferred. If only one donor had been implicated, s/he would have been indefinitely deferred.

27. It has been determined that a patient has posttransfusion hepatitis and received blood from eight donors. There is nothing to indicate that these donors may have been likely to transmit hepatitis. What action must be taken initially? A. Defer all donors indefinitely from further donations. B. Repeat all hepatitis testing on a fresh sample from each donor. C. Notify the donor center that collected the blood. D. Interview all implicated donors.

C. Red blood cells and whole blood must be stored between 1 and 6°C in a monitored refrigerator with a recording thermometer and audible alarm system. During transportation between collection and transfusion facilities, blood must be packed in well-insulated containers designed to maintain a temperature range of 1-10°C. Wet ice in a leak-proof plastic bag is placed on top of the blood. The amount of ice to be used is dictated by the transportation time, the number of units packed, and the ambient outside temperature.

28. The temperature range for maintaining red blood cells and whole blood during shipping is A. 0-4°C B. 1-6°C C. 1-10°C D. 5-15°C

C. In addition to the minimum number of platelets that should be present, 5.5 X 10^10, the pH of the unit must be 6.2 or higher in at least 75% of the units. The units should be assayed at the end of the allowable storage period. A donor who has taken aspirin should not be the sole donor of platelets for a patient. Aspirin has an adverse effect on platelet aggregation.

29. Platelets play an important role in maintaining hemostasis. One unit of donor platelets derived from whole blood should yield platelets. A. 5.5 X 10^6 B. 5 X 10^8 C. 5.5 X 10^10 D. 5 X 10^10

A. Hepatitis viruses and HIV have extended incubation periods in which exposure has occurred but neither serological nor clinical manifestations of the disease are evident. The current screening tests, although quite sensitive, are unable to detect the viruses if testing is performed during this incubation period. To safeguard against the possibility that the donor received blood or blood products collected during the incubation period, a 12-month deferral is incurred to allow for fulmination of the disease.

3. Donors who have received blood or blood products within 12 months of when they desire to donate are deferred to protect the recipient because the A. Blood could have transmitted hepatitis (HBVorHCV)orHIV B. Blood may have two cell populations C. Donor may not be able to tolerate the blood loss D. Donor red cell hemoglobin level may be too low

C. Platelets must be stored in sufficient plasma volume to prevent the pH from falling below 6.2 at the time of expiration. Lactic acid is a byproduct of anaerobic glycolysis during platelet storage, causing a drop in plasma pH and a loss of discoid shape, and hence viability. Second generation platelet bags allow better gas exchange, permitting platelets to be stored for longer periods of time at a favorable pH.

30. The pH of four platelet concentrates is measured on the day of expiration. The pH and plasma volumes of the four units are as follows: pH 6.0, 45 mL; pH 5.5, 38 mL; pH 5.8, 40 mL; pH 5.7, 41 mL. What corrective action is needed in product preparation to meet AABB Standards for platelet production? A. No corrective action is necessary. B. Recalibrate pH meter. C. Increase final plasma volume of platelet concentrates. D. Decrease final plasma volume of platelet concentrates.

C. Red blood cells expire 24 hours from the time the hermetic seal is broken, provided they are maintained at 1-6°C during the storage period. The new expiration date and time must be placed on the label and in the appropriate records. An open system exposes the blood to possible bacterial contamination. Blood may be frozen for up to 6 days after collection when maintained at 1-6°C in a closed system. If the seal is inadvertently broken on a rare unit during component preparation, the red cells may be salvaged by glycerolization and freezing, providing this is accomplished within the 24-hour restriction.

31. During preparation of platelet concentrate, the hermetic seal of the primary bag is broken. The red blood cells A. Must be discarded B. May be labeled with a 21-day expiration date if collected in CPD C. Must be labeled with a 24-hour expiration date D. May be glycerolized within 6 days and stored frozen

D. The AABB Standards require that an authorized individual (such as a supervisor or medical director) review the standard operating procedures (SOPs), policies, and process annually and document the review. The SOPs should be reviewed and revised as needed to reflect the techniques used by the laboratory. It is prudent to conduct a review before a scheduled inspection and following publication of each new edition of AABB Standards to ensure conformance with new requirements.

32. The blood bank procedures manual must be A. Revised annually B. Revised after publication of each new edition of AABB Standards C. Reviewed prior to a scheduled inspection D. Reviewed annually by an authorized individual

B. In order to meet the current AABB Standards for leukocyte reduction to prevent HLA alloimmunization or CMV transmission, the donor unit must retain at least 80% of the original red cells and the leukocytes must be reduced to less than 5 X 106. Leukocyte reduction may also prevent febrile reactions in two ways: (1) By reducing the number of leukocytes in the component to a low enough level, one can prevent febrile reactions when patients have leukocyte antibodies. (2) Cytokines are also known to cause febrile reactions. If prestorage leukocyte reduction is done, cytokine generation should be prevented.

35. In order to meet the current AABB Standards for leukocyte reduction to prevent HLA alloimmunization or CMV transmission, the donor unit must retain at least__________ of the original red cells and leukocytes must be reduced to less than___________ A. 85%, 5 X 10^8 B. 80%, 5 X 10^6 C. 75%, 5 X 10^5 D. 70%, 5 X 10^4

D. ABO grouping must be determined by doing both cell and serum grouping. The Rh type must be determined by direct agglutination with anti-D; if negative, the test is incubated and converted to the antiglobulin test to detect weak D phenotypes. Performing an antibody screening test on the serum or plasma of a donor is required when the donor has a history of transfusion or pregnancy. For practical purposes, most donor centers screen all donors for clinically significant antibodies. The absence of hepatitis B surface antigen (HBsAg) and HIV must be confirmed using a method currently licensed by the FDA. The test for hepatitis B surface antibody (HBsAb) is not required

36. Which of the following tests is/are not performed during donor processing? A. ABO and Rh grouping B. HBsAg C. HIV-l-Ag D. HBsAb

C. In the average-size adult (70 kg), a unit of platelet concentrate should raise the platelet count by 5000-10,000/uL if there are no other complicating factors to cause decreased survival. Complicating factors include fever, sepsis, disseminated intravascular coagulation (DIG), and HLA sensitization. One apheresis platelet unit is equivalent to 6-8 units of pooled platelet concentrate and has the advantage of decreased donor exposure.

37. A 70-kg man has a platelet count of 15,000/uL, and there are no complicating factors such as fever or HLA sensitization. If he is given a platelet pool of 6 units, what would you expect his posttransfusion count to be? A. 21,000-27,000/uL B. 25,000-35,000/uL C. 45,000-75,000/uL D. 75,000-125,000/u

A. The ABO group on all units and the Rh type on all D-negative units must be repeated by the transfusing facility for units of RBCs or whole blood collected and processed at another facility. This is generally accomplished by repeating the cell grouping only. To save time and reagent cost, it is convenient to test units labeled group O with anti-A,B only. Confirmatory testing for weak D is not required. The Rh type of units labeled D-positive need not be confirmed. Repeat antibody screening and viral testing are not required.

38. Which of the following tests on donor red blood cells must be repeated by the transfusing facility when the blood was collected and processed by a different facility? A. Confirmation of ABO group and Rh type of blood labeled D-negative B. Confirmation of ABO group and Rh type C. Weak D on D-negatives D. Antibody screening

D. During autologous presurgical donation, a different set of criteria is used for donor acceptability. All the conditions listed are acceptable with the exception of the bacteremia. The bacteria may proliferate in the stored blood and be reinfused into the donor (patient) during or after the surgery. Even treatment for a suspected bacteremia is a contraindication for autologous donation.

4. Which of the following conditions would contraindicate autologous presurgical donation? A. Weight of 100 pounds B. Age of 14 years C. Hemoglobin of 12 g/dL D. Mild bacteremia

D. Recipients of human growth hormone are deferred indefinitely because of the risk of transmission of Creutzfeldt-Jakob disease. Recipients of recombinant growth hormone incur no deferral. A history of either syphilis or gonorrhea causes a deferral of 12 months from completion of treatment. Accutane®, a drug used to treat acne, may be a teratogen and requires a 1-month deferral after receipt of the last dose.

5. Which of the following donors would be deferred indefinitely? A. History of syphilis B. History of gonorrhea C. Accutane® treatment D. Recipient of human growth hormone

A. Of the viruses listed, CMV is the only one that resides exclusively in leukocytes. Although CMV transmission is not a problem for most patients, it can cause serious disease in low-birthweight neonates of CMV-negative mothers and immunocompromised patients. These patients should be transfused with CMV seronegative or leukocyte-reduced cellular components.

6. Which of the following viruses resides exclusively in leukocytes? A. CMV B. HIV C. HBV D. HCV

D. The body makes five different immunoglobulins: IgA, IgD, IgE, IgG, and IgM. IgG makes up about 80% of the total serum immunoglobulin. Although IgA is more abundant than IgM (13% versus 6%), IgM is more common as a blood group antibody.

64. Most blood group antibodies are of what immunoglobulin classes? A. IgA and IgD B. IgA and lgM C. IgE and lgD D. IgG and lgM

D. All red blood cells contain some amount of H substance. The only exception is the very rare Oh (Bombay) individual because these persons lack the H gene that codes for H substance. Group O cells contain the most H substance, and AtB cells contain the least amount of H substance. The order of decreasing reactivity with anti-H is: O > A2 > A2B > B > A1 > A1B

66. Which of the following blood groups reacts least strongly with an anti-H produced in an AjB individual? A. Group O B. Group A2B C. Group A2 D. Group A1

B. Two genes control Rh antigen activity. RHD controls the expression of D antigen, and RHCE determines the C, E, c, and e antigens. RHD is absent or inactive in D-negative individuals. Alleles of RHCE are RHCe, RHcE, and RHce. The RH is often dropped (for example CE, Ce, cE, ce).

67. How many genes encode the following Rh antigens: D, C, E, c, e? A. One B. Two C. Three D. Four

C. Donors who have ingested aspirin within 36 hours of donation need not be excluded for whole blood donation. The platelets prepared from such donors should be labeled and may be used in a multiple pool prepared for adult transfusion. Because aspirin affects platelet function, a single unit of platelet concentrate from this donor should not be used for platelet therapy for infants and neonates. This donor should not be the sole source of platelets and, therefore, would be temporarily deferred as a plateletpheresis donor.

7. A donor indicates that he has taken two aspirin tablets per day for the last 36 hours. The unit of blood A. May not be used for pooled platelet concentrate preparation B. Should not be drawn until 36 hours after cessation of aspirin ingestion C. May be used for pooled platelet concentrate preparation D. May be used for red blood cells and fresh-frozen plasma production, but the platelets should be discarded

C. the Le gene codes for a transferase enzyme, L-fucosyl transferase, which attaches fucose to the subterminal sugar on the Type 1 precursor substance producing Lea substance. This occurs independently of the ABH secretor status. For Leb as well as ABH substances to be present in the secretions, both the Se gene and the Le gene must be present. The Se gene produces a transferase that attaches a fucose to the terminal sugar on precursor substance, forming H substance in the secretions. Type 1H and Type 2H are the precursors for A and B substance. The Le gene can act upon Type 1H as well to form Leb substance; therefore, a nonsecretor who has a Le gene will only secrete Lea, whereas a secretor will secrete a little Lea and a lot of Leb substance

70. If a person has the genetic makeup Hh, AO, LeLe, sese, what substance will be found in the secretions? A. A substance B. H substance C. Le^a substance D. Le^b substance

B. Lectins are proteins present in plants, often derived from the seeds of plants. Lectins can also be found in lower forms of animal life. The specificity of lectins is for carbohydrate moieties and, used undiluted, they will often react with all human red blood cells. The lectins used in blood banking are most often derived from the seeds of a plant, then diluted to achieve the desired specificity.

72. Lectins are useful in determining the cause of abnormal reactions in blood bank serology. These lectins are frequently labeled as anti-H, anti-A1 etc. The nature of these lectins is explained by which of the following? A. An early form of monoclonal antibody produced in nonvertebrates B. A plant substance that chemically reacts with certain RBC antigens C. Naturally occurring antibodies in certain plants D. The ability of plants to respond to RBC antigens by antibody production

D. The sugar L-fucose is attached to the terminal sugar of precursor substance by a fucosyl transferase. The fucosyl transferase coded by the H gene adds the fucose to the precursor substance on the red cells. The fucosyl transferase encoded by the Se gene adds a fucose to the precursor substance in the same configuration in the secretions. In both cases, the resulting configuration is called H substance. Without H substance present, the sugars giving A or B antigenic activity cannot attach.

73. Which of the following sugars must be present on a precursor substance for A and B antigenic activity to be expressed? A. D -Galactose B. N-Acetylgalactosamine C. Glucose D. L-Fucose

B. The complement cascade has many functions in the body associated with immunity and inflammation. The last stages of the complement cascade ultimately lead to RBC lysis. IgM is the immunoglobulin that most readily activates complement. The IgG immunoglobulins can activate complement to a lesser extent. IgG3 activates complement more efficiently than the other IgG subclasses. Although glucose-6-phosphate dehydrogenase deficiency can result in the lysis of RBCs in the presence of fava beans and certain drugs, the enzyme itself does not lyse RBCs. Albumin and antihuman globulin serum can be used in blood bank testing and do not harm RBCs.

74. An antigen-antibody reaction alone does not cause hemolysis. Which of the following is required for red blood cell lysis? A. Albumin B. Complement C. Glucose-6-phosphate dehydrogenase (G6PD) D. Antihuman globulin (AHG)

B. The answer is based upon the frequencies of genes. The genes that code for the haplotypes DCe and dee are high in the white population. A DCe/dce genotype has a frequency of approximately 31.1% in the general white population. The other two possible choices among the answers that would fit the typing results are DCe/Dce and Dce/dCe and have frequencies of approximately 3.4% and 0.2%, respectively. DCe/DcE is incorrect because the typing does not indicate that the E antigen is present.

75. A white female's red blood cells gave the following reactions upon phenotyping: D+ C+ E- c+ e+. Which of the following is the most probable Rh genotype? A. DCe/Dce B. DCe/dce C. DCe/DcE D. Dce/dCe

C. All these genotypes have a low frequency in the black population. DCe/dcE is the rarest, with a frequency of <0.1%. DCe/DcE is the most frequent, with an occurrence of 3.7%.

76. A black patient has the following Rh phenotype: D+ C+ E+ c+ e+. Which of the following genotypes is the least probable? A. DCE/dce B. DCe/DcE C. DCe/dcE D. DcE/dCe

A. Red blood cells that have either the C or D antigen also have the G antigen. When anti-G is made, it is capable of reacting with the G antigen on both C-positive and D-positive red blood cells, therefore appearing to be anti-C plus antiD. In the stated case, the immunizing red blood cells were D-negative and C-positive. Therefore, what appears to be a combination of anti-D and anti-C is anti-G or a combination of anti-C and anti-G.

77. An individual of the dee/dee genotype given dCe/dce blood has an antibody response that appears to be anti-C plus anti-D. What is the most likely explanation for this? A. The antibody is anti-G. B. The antibody is anti-partial D. C. The antibody is anti-Cw. D. The reactions were read incorrectly.

B. The unit from the DCe/dce donor has the c antigen that the patient lacks. This antigen is a good immunogen. Although this patient can form the anti-E antibody, the donor cells lack the E antigen. Thus, the donor cells cannot stimulate the production of anti-E. Remember, "d" simply implies the absence of D and is not an antigen.

78. If a patient has the Rh genotype DCe/DCe and receives a unit of red blood cells from a DCe/dce individual, what Rh antibody might the patient develop? A. Anti-C B. Anti-c C. Anti-d D. Anti-E

C. Under no circumstances should any blood component from a high-risk donor be released from the donor center to a transfusion unit. Donors in high-risk groups for AIDS must be deferred from donating. If high-risk activity becomes known retrospective to blood donation (such as in the self-exclusion process), the blood components from the donation must be retrieved and destroyed.

8. Which of the following best describes what must be done with a unit of blood drawn from a donor who is found to be at high risk of contracting acquired immune deficiency syndrome (AIDS)? A. Hold unit in quarantine until donor diagnosis is clarified. B. Use the blood for research dealing with AIDS. C. Properly dispose of unit by autoclaving or incineration. D. Use the plasma and destroy the red blood cells.

A. Occasionally, D-positive people make an apparent anti-D. The D antigen is made up of several epitopes or antigenic determinants. Those individuals missing one or more of these epitopes are called partial D. When individuals lack one or more of these epitopes, they can make an antibody, after appropriate stimulation, against the epitope or epitopes that they lack. All of these antibodies to D epitopes will react with "normal" D-positive cells that have all of the epitopes on the D antigen. Therefore, a D-positive or weak-D person appears to make an anti-D.

82. If a D-positive person makes an anti-D, this person is probably A. Partial D B. D-negative C. Weak D as position effect D. Weak D due to transmissible gene

A. The k antigen is a high-frequency or "public" antigen present in greater than 99% of the random population. The probability of encountering an individual who is k-negative and capable of producing the corresponding antibody after red blood cell stimulation is very low. Kell system antigens are good immunogens, second only to those of the Rh system. Although it is true that Kellnul1 individuals are very rare, they do not make a separable anti-k.

83. A serum containing anti-k is not frequently encountered. This is because A. People who lack the k antigen are rare B. People who possess the k antigen are rare C. The k antigen is not a good immunogen D. Kellnull people are rare

C. Anti-Jka often declines in the serum to below detectable levels. Therefore, when a patient has been transfused and makes anti-Jka and then is not transfused again for a long time, the subsequent antibody screen may not reveal the presence of the anti-Jka. An intravascular delayed transfusion reaction is characteristic of the Kidd antibodies because, after a second stimulation, there is a slow rise in the antibody titer and they activate complement very well. In the case of the patient in question, the antibody has been missed and he received Jk(a+) cells at some point during his stay in the other hospital. This caused a severe delayed hemolytic transfusion reaction with intravascular hemolysis.

84. A victim of an auto accident arrives in the emergency department (ED) as a transfer from a hospital in a rural area. The patient has been in that facility for several weeks and has received several units of red blood cells during that time. The ED resident orders 2 units of RBCs for transfusion. The sample sent to the blood bank is centrifuged and the cell-serum interface is not discernable. A subsequent sample produces the same appearance. You would suspect that the patient has A. Autoimmune hemolytic anemia B. Anti-Fya C. Anti-Jka D. Paroxysmal nocturnal hemoglobinuria

A. The Xg^a antigen is produced by a gene on the X chromosome. Because women inherit two X chromosomes, there is a higher incidence of the antigen in females. The antibody is usually detected by an antiglobulin test, and the antigenie activity is depressed by enzymes.

85. Which of the following is a characteristic of the Xg^a blood group system? A. The Xg^a antigen has a higher frequency in women than in men. B. The Xg^a antigen has a higher frequency in men than in women. C. The Xg^a antigen is enhanced by enzymes. D. Anti-Xg^a is usually a saline-reacting antibody.

D. To ensure that an antiserum is reacting properly, positive and negative controls must be tested. The antiserum must be tested against a cell that is negative for the corresponding antigen to ensure that no interfering substances are present that will cause false positives. It must also be tested against a cell positive for the corresponding antigen. A heterozygous cell is used to determine whether or not the antiserum will be reactive with the smaller number of antigen sites on the RBCs seen in heterozygotes. For example, when using anti-K, you would test a kk (K-k+) cell and a Kk (K+k+) cell.

86. Testing needs to be done with an antiserum that is rarely used. The appropriate steps to take in using this antiserum include following the manufacturer's procedure and A. Performing a cell panel to be sure that the antiserum is performing correctly B. Performing the testing on screen cells C. Testing in duplicate to ensure the repeatability of the results D. Testing a cell that is negative for the antigen and one that is heterozygous for the antigen

D. Kidd antibodies are often weak and deteriorate during storage. They are usually IgG, antiglobulin reactive only, and complement dependent. Reactions are enhanced when enzyme-treated panel cells are used. Kidd antibodies also show dosage, and the titer may drop to undetectable levels after the primary response. For this reason, they are often implicated in delayed hemolytic transfusion reactions when there is no previous record of the presence of the antibody. A Kidd antibody rarely occurs singly in a patient's serum but is often seen accompanying other antibodies

87. Which of the following is a characteristic of Kidd system antibodies? A. Usually IgM antibodies B. Corresponding antigens are destroyed by enzymes. C. Usually strong and stable during storage D. Often implicated in delayed hemolytic transfusion reactions

B. Enzymes denature the Fya and Fyb antigens and render panel cells Fy(a-b-). Therefore, antiFya and anti-Fyb will not react with enzymetreated red cells. These Duffy antibodies are clinically significant. They can cause hemolytic transfusion reactions and mild hemolytic disease of the newborn. They are usually IgG antibodies and are best detected by the antiglobulin technique

88. Which of the following statements is not true of anti-Fya and anti-Fyb? A. Are clinically significant B. React well with enzyme-treated panel cells C. Cause hemolytic transfusion reactions D. Cause a generally mild hemolytic disease of the newborn

B. Chido (Cha) and Rodgers (Rga) antigens are actually "pieces" of complement component 4 (C4) and are present on some RBCs, although not an RBC antigen. Anti-Cha and anti-Rga have a relatively high titer with a low avidity (HTLA) for the corresponding antigen, often not stronger than 1 + agglutination. Clinically, these antibodies are usually not significant. They are IgG and are detected by the indirect antiglobulin test. They can be neutralized with pooled normal human plasma, because complement components are always present in some amount in human plasma. Pooled plasma is used because the amount of C4 in the plasma varies between individuals. All of the other antibodies mentioned in the answers are RBC antigens and cannot be neutralized in this way.

89. Which of the following antibodies can be neutralized with pooled human plasma? A. Anti-Hy and anti-Ge: 1 B. Anti-Ch^a and anti-Rg^a C. Anti-Co^a and anti-Co^b D. Anti-Do^a and anti-Js^b

C. Plasma protein fraction (PPF) and albumin preparations (5% and 20%) provide colloid replacement and volume expansion with virtually no risk of viral transmission. These are pooled products and are pasteurized by heating to 60°C for 10 hours. Other products, such as clotting factor concentrates, are usually treated by solvent-detergent method to inactivate viruses with lipid envelopes such as HBV, HCV, HIV, and HTLV-I.

9. Which of the following is least likely to transmit hepatitis? A. Cryoprecipitate B. RBC C. Plasma protein fraction (PPF) D. Platelets

D. Anti-U is a clinically significant IgG antibody causing hemolytic transfusion reactions and hemolytic disease of the newborn. All white people appear to be U+, because no U negatives have been found. However, about 99% of blacks are U+ and 1% are U-. Those people who are U- are also S-s- and lack the entire Ss sialoglycoprotein (glycophorin B) except for very rare genetic mutations.

90. Which of the following statements is not true about anti-U? A. Is clinically significant B. Is only found in black individuals C. Only occurs in S-s- individuals D. Only occurs in Fy(a-b-) individuals

B. Although the patient's antibody screening is negative at this time, previous records show that the patient had an anti-E. Anti-E is a significant IgG antibody; only blood negative for the E antigen should be transfused to the patient. Failure to give E-negative blood could result in a serious delayed transfusion reaction due to an anamnestic response.

91. A patient had an anti-E identified in his serum 5 years ago. His antibody screening test is now negative. To obtain suitable blood for transfusion, what is the best procedure to use? A. Type the patient for the E antigen as an added part to the crossmatch procedure. B. Type the donor units for the E antigen and crossmatch the E-negative units. C. Crossmatch donors with the patient's serum and release the compatible units for transfusion. D. Perform the crossmatch with enzymetreated donor cells, because enzymetreated red cells react better with Rh antibodies.

B. For control purposes the cell should have the weakest expression of the antigen in question; that would be an Fy(a+b+) cell. A weaker cell from a heterozygote is used because a weak antiserum might detect an antigen from a homozygote but not from a heterozygote (dosage effect). If this should happen, then red blood cells might be mistyped as Fy(a-) when in fact the cells are Fy(a+).

92. A patient's red blood cells are being typed for the Fya antigen. Which of the following is the proper cell type of choice for a positive control of the anti-Fya reagent? A. Fy(a+b-) B. Fy(a+b+) C. Fy(a-b+) D. Fy(a-b-)

B. Most antibodies in the Kell system are red blood cell stimulated. They are generally IgG antibodies and usually detected in the antiglobulin phase of testing. Because of their nature, they have been implicated in both transfusion reactions and hemolytic disease of the newborn. The other choices are usually IgM antibodies that cannot cross the placenta and are rarely involved in transfusion reactions

93. Which of the following antibodies has been clearly implicated in transfusion reactions and hemolytic disease of the newborn? A. Anti-I B. Anti-K C. Anti-Lea D. Anti-N

A. Antibodies can be ruled out using only one cell that is homozygously antigen positive and nonreactive at all phases of testing with the patient serum. Preferably, two or three cells that are positive for the antigen and nonreactive with the patient serum increase confidence. Antibodies in the Duffy, Kidd, and MNSs systems often show dosage. Because there are more antigenic sites on homozygous cells than on heterozygous cells, these antibodies react more strongly with homozygous cells [cells with 2 "doses" of the antigen, such as Jk(a+b-)] than with cells that carry a single "dose" of the antigen [such as Jk(a+b+)]. These antibodies can be ruled out only using homozygous cells that are positive for the antigen and do not react with the patient serum. Of the answers available, "A" is the best choice. Additional antibodies may not be ruled out when a standard of three cells that are positive for the antigen and nonreactive with the patient serum is used.

94. Which of the following antibodies would require additional testing in order to be ruled out? A. Anti-E, -K, -Kpa, -Jsa, -Jkb B. Anti-E, -S, -Leb, -K, -Kpa, -Fya C. Anti-E, -S, -Lea, -K, -Kpa, -Jsa, -Fya, -Jka D. Anti-E, -Lea, -K, -Kpa, -Jsa, -Fyb, -Jka, -Jkb

B. The most likely combination of antibodies is anti-E plus anti-K. More than one antibody is likely because the reactions seen are of varying strengths. The panel cells that did not react with the patient serum are all lacking both the E and K antigens. The E antigen is present on Cells #4, #5, and #9. The K antigen is present on Cells #4 and #7. Note that Cell #4 has both the E and K antigens and reacts 4+ at AHG. Cells #5 and #9 have the E antigen, but not the K antigen, and both cells react 3+ at AHG. Cell #7 has the K antigen but not the E antigen and reacts 2+ at AHG. Therefore, the anti-E is stronger than the anti-K, and when both antigens are present the reaction is stronger than a reaction with one antibody alone.

95. The most likely antibody(ies) in the patient's serum is(are) A. Anti-S and anti-E B. Anti-E and anti-K C. Anti-Fyb showing dosage D. Anti-K, anti-Jsa, and anti-Le

C. Cells #1, #4, and #7 are the cells from this panel that will be helpful in confirming the antibodies, anti-E and anti-K, and ruling out the other possible antibodies. Cell #1 is both E- and K-negative and should not react with the patient's serum. However, Cell #1 is also S+s-, Le(a+), Jk(a-b+), and Fy(a-b+) and can help to rule out all of the other possible antibodies. Cell #4 is E+, K-, S-, s+, Le(a-), Jk(b-), and Fy(b-). This cell can help confirm the presence of anti-E. Cell #7 is E-, S-, Le(a-), K+, Jk(b-), and Fy(b-). This cell can help confirm the presence of anti-K.

96. From the cells in red cell panel chart 2, choose a selected cell panel to help identify the antibody(ies) in the patient described in question 95. A. 1,2,5,9,10 B. 2,6,7,10 C. 1,4,7 D. 2,3,4,6,9

C. Anti-Lea, -Leb, and -Pt may all be neutralized by commercially available soluble substances. Lea and Leb are not RBC antigens but are plasma substances that are absorbed onto RBCs in the circulation. Soluble antigens are more available to the antibodies and can attach to soluble antibodies more readily than particulate antigens. Thus, the plasma (soluble) Lea and Leb can be used to bind to the soluble antibodies, leaving no antibody to react with the particulate antigen on the RBCs. Soluble Pt can be obtained from several sources and can be used in the same way to preferentially bind the anti-Pp leaving no anti-Pj to react with the particulate P} antigen on the RBCs.

97. Often when trying to identify a mixture of antibodies, it is useful to neutralize one of the known antibodies. Which one of the following antibodies is neutralizable? A. Anti-D B. Anti-Jka C. Anti-Lea D. Anti-M

C. Anti-N is the only antibody listed that is generally a room temperature saline agglutinin. The remaining choices, anti-Fya, anti-Jkb, and antiU, are best detected at the antiglobulin phase of testing. Remember, this is where these antibodies are optimally reactive; it does not mean they will never react at other phases of testing. Some antibodies just don't read the books!

98. Which of the following antibodies does not match the others in terms of optimal reactive temperature? A. Anti-Fya B. Anti-Jkb C. Anti-N D. Anti-U

D. The Fya antigen is destroyed by enzyme treatment. Therefore, the anti-Fya seen in the initial panel will not react in an enzyme-treated panel. Enzyme-treated cells react extremely well with antibodies of the Rh system. Because the second antibody is suspected of being a weak anti-C, the antibody will react more strongly with an enzyme-treated panel than it did in the initial LISS panel. Although one cannot rule out antibodies to Duffy system, MNSs system, or Xga using an enzyme-treated panel, all other major blood group system antibodies present in the patient's serum should react in this medium. An elution removes antibody from the RBCs; in our scenario, the antibody is seen in the serum. Absorption of the anti-Fya from the patient serum could be useful; however, finding cells that lack all of the antigens lacked by the patient to avoid missing an alloantibody is a difficult and time-consuming task. Additionally, absorption will unavoidably dilute the patient's serum slightly and may dilute the weak second antibody to a point where it cannot be identified. Antigen typing the patient's cells is useful in determining whether or not the patient can form anti-C and anti-Fya, but it will not exclude any other antibodies nor confirm the presence of any specific antibody.

99. A recently transfused patient's serum has a positive antibody screen. The panel performed at IS, in LISS at 37°C, and at AHG shows a strong anti-Fya and a weak possible anti-C. To confirm the anti-C, you would perform an A. Elution B. Absorption C. Antigen typing D. Enzyme panel

11.C. 12.A. 13.D. 14.B. 15.C. 16.D. 17.A. 18.A. Discrepancies in ABO blood grouping may occur for numerous reasons. Any discrepancy between cell and serum grouping must be resolved before blood is identified as belonging to a particular ABO group. The presence of an acquired B antigen on cells that are normally group A can be found in some disorders, where gram-negative bacteria have entered the circulation. The serum will contain an anti-B, which will not agglutinate the patient's own cells that have the acquired B antigen. The red cell reaction with anti-B reagent may be weaker than usual. Protein abnormalities of the serum such as are present in multiple myeloma may cause the presence of what appear to be additional antibodies. The rouleaux of the red blood cells caused by the excess globulin may appear to be agglutination. Saline replacement of the serum and resuspension of the cells will usually resolve the problem in the serum grouping. Washed red blood cells should be used for the cell grouping. Infants do not begin making antibodies until they are 3 to 6 months of age. Newborns therefore will not demonstrate the expected antibody(ies) on reverse grouping. The antibody that is present is probably IgG from the mother that has crossed the placenta. An A2 individual has the ability to make an antibody that agglutinates Aj red cells. This anti-Aj will cause a serum grouping discrepancy, but the antibody is almost always naturally occurring and clinically insignificant. A patient's serum may have antibodies to the yellow dye used to color anti-B reagents. If serum or plasma suspended red cells are used in the cell grouping, a false positive reaction may occur. Using washed cells will eliminate the problem. Patients who are immunodeficient may have such depressed immunoglobulins that their serum does not react with the expected A and B reagent red cells. An unexpected IgM antibody in the serum will react at room temperature and may interfere with ABO typing. Reverse grouping cells carry all of the normal RBC antigens. Therefore, they can react at room temperature with anti-M, anti-N, anti-Pp etc. O cells may also react if they carry the antigen corresponding to the antibody in the patient's serum. Thus a patient with anti-M in his serum could react with both reverse grouping cells and the O cells if all were positive for the M antigen. A patient with cold hemagglutinin disease (CHD) may have a discrepancy affecting both cell and serum groupings. The red blood cells should be washed with warm saline before typing; the serum and reagent A and B cells should be prewarmed before mixing and testing and converted to the antiglobulin test if necessary.

Eight blood samples are received in the laboratory for ABO grouping. For each patient (questions 111-118), indicate the most likely cell and serum reactions selected from the lettered reaction matrix. 111. A patient with an acquired antigen due to infection with gram-negative bacteria 112. A patient with multiple myeloma 113. A newborn 114. An A2 individual making an anti-Aj 115. A patient with antibodies to acriflavin (a yellow dye) 116. A patient who is immunodeficient 117. A patient with an unexpected IgM antibody in his serum 118. A patient with cold hemagglutinin disease (CHD)

124. A. The racial origin of this donor is probably black. This origin can be determined by looking at the Duffy (Fy) phenotype. About 70% of American blacks are Fy(a-b-). This phenotype is extremely rare in whites.

For questions 124-132, refer to red cell panel chart 3. 124. The racial origin of the donor of Cell #3 is most likely A. Black B. Eskimo C. Oriental D. White

125.D. Donor 5 is homozygous for the following genes: Ce, s, k, Jka, Fya, because the corresponding antigen is produced and the antithetical antigen is not being produced by an allele (for example, C+c- implies homozygosity: CC). The donor cannot be homozygous for M, because its allele is producing N antigen. There is no way to tell whether Pl is homozygous, because it lacks a co-dominant allele and Pl does not show dosage. There is no Leb gene. The antigen is produced by the action of the Le gene on Type 1 H. The Lewis genes are Le and the amorph le, and dosage is not observed.

For questions 124-132, refer to red cell panel chart 3. 125. The donor of Cell #5 is homozygous for which combination of the following genes? A. Ce, Pp M, s, k, Jka, Fya, Leb B. Ce, Pj, s, k, Jka, Fya, Leb C. Ce, s, k, Jle, Fya, Leb, P1 D. Ce,s,k,Jka,Fya

126. A. Anti-Fya can be identified by eliminating specificities where the corresponding antigens appear on the panel cells that do not react. The differences in the strength of reactivity can be explained by the fact that the Duffy antigens show dosage (react stronger with cells from homozygotes). Cells #1 and #6 are from Fy" heterozygotes [Fy(a+b+)]. Cells #4 and #5 are from Fy" homozygotes [Fy(a+b—)]. When eliminating an antibody specificity known to show dosage, it is best to have a negative reaction with a panel cell from a donor who is homozygous for the corresponding gene. Fya and Fyb antigens are destroyed by enzymes. Although the Fy(a-b-) type is common in blacks, the frequency of Fya in whites is about 66%. Anti-E and anti-s should be ruled out with Fy(a-) cells from individuals who are homozygous for E and s (in other words, E+e- and S-s+).

For questions 124-132, refer to red cell panel chart 3. 126. After testing a patient's serum with the panel, one observes there are no reactions at IS or 37°C with Cells #1-8. There is a 1 + AHG reaction with Cells #1 and #6 and a 3 + AHG reaction with Cells #4 and #5. All other Cells, #2, #3, #7, and #8, are negative at AHG. Which of the following statements is true? A. Anti-Fya appears to be present. B. Anti-Fya is present as well as an antibody that is reacting with an undetermined antigen on Cells #4 and #5. C. Ficin will enhance the reactions of the antibody(ies) present. D. Anti-Fya is present but can be ignored because most people are Fy(a-b-).

127. C. Serum must be present to cause rouleaux formation; it should not occur at the antiglobulin phase of testing when the rouleaux-producing properties have been removed by washing. Warm and cold autoantibodies result in a positive autocontrol, usually equal in strength to reactivity observed with reagent red cells. Antibodies directed against preservatives in potentiating media should also react in the autocontrol. When the autocontrol is nonreactive and all panel cells are uniformly positive, one should suspect the presence of an alloantibody directed against a "public," or high-frequency, antigen. A selected panel of red cells, each lacking a different high-frequency antigen, should be tested until a compatible cell is found. The patient's red cells may be typed for a variety of highfrequency antigens. If such an antigen is found to be missing on the red cells, the corresponding serum antibody is likely that specificity.

For questions 124-132, refer to red cell panel chart 3. 127. The serum of a patient tested with the reagent red cell panel using a low-ionicstrength-saline (LISS) additive demonstrates 3+ reactivity with Cells #1-8 at the antiglobulin phase. The autocontrol is negative. This pattern of reactivity is most likely due to A. Rouleaux formation B. Warm autoantibody C. Alloantibody directed against a highfrequency antigen D. Antibody directed against a preservative present in LISS

128. B. Cell #7 is negative for the high-frequency antigen k (cellano). Many other specificities cannot be ruled out because there is only one negative reaction. Treating the panel cells with dithiothreitol (DTT) destroys Kell system antigens. If no reactions are seen when the panel is repeated with DTT-treated cells, then many other clinically significant antibodies can be ruled out and the presence of anti-k would be supported. If the patient has not recently been transfused, his cells should be typed with anti-k and would be expected to be k-negative. Proteolytic enzymes neither destroy Kell system antigens nor enhance their reactions with Kell system antibodies. Treating serum with DTT will destroy IgM antibodies by cleaving disulfide bonds of the pentamer and would not be helpful because anti-k is generally IgG.

For questions 124-132, refer to red cell panel chart 3. 128. A patient's serum reacts with all the panel cells except Cell #7 at the antiglobulin phase only. Which of the following techniques would be most helpful at this point? A. Treat the panel cells with a proteolytic enzyme and repeat the panel with untreated serum. B. Treat the panel cells with dithiothreitol (DTT) and repeat the panel with untreated serum. C. Treat the patient's serum with dithiothreitol (DTT) and repeat the panel with treated serum. D. Treat the patient's serum with a proteolytic enzyme and repeat the panel with treated serum.

129.C. From the presence of positive reactions taking place at two different temperatures, it appears that there are two different antibodies reacting. There is a cold antibody reacting with Cells #3 and #8 at immediate spin and a warm antibody reacting with Cells #1, #2, #3, and #4. It is unlikely that the cold antibody is carrying over to a warmer phase, because there is no 37°C reaction with Cell #8.

For questions 124-132, refer to red cell panel chart 3. In addition to red cell panel chart 3, use the following information to answer questions 129-132 129. From the reactions given, it appears that there is(are) A. One antibody reacting B. One antibody reacting that shows dosage C. "Cold" and "warm" antibodies reacting D. Two "warm" antibodies reacting

(60:D, 61:C, 62:B, 63:A) Patients with warm autoimmune hemolytic anemia (AIHA) secondary to oc-methyldopa respond rapidly following cessation of the drug. They can usually be managed without transfusion. The DAT (direct antiglobulin test) may not revert to negative for up to 6 months or even longer. Leukocytereduced blood components (<5 X 106) are indicated in order to avoid repeated febrile episodes, CMV transmission, and alloimmunization to leukocytes. Leukocytes can be removed by filtration, centrifugation, or washing. Currently, the preferred and most efficient method is filtration with commercially available adsorption filters capable of reducing leukocytes to the required level. Patients with normovolemic anemia should be transfused with RBCs, which provide the red blood cells needed to correct the anemia in the smallest volume. These patients may not be able to tolerate whole blood because of the volume increase. It is not necessary to use leukocyte-reduced RBC for patients with normovolemic anemia. Thrombocytopenia means there is a lack of platelets. Often platelet counts drop in acute leukemia and during the subsequent treatment. Platelet counts below 20,000/uL are not uncommon under the circumstances, and the patient is considered to have severe thrombocytopenia. Leukocyte-reduced platelets will lower the chance of alloimmunization and are routinely given prophylactically to leukemia patients.

For the following patients (questions 60-63), indicate the component of choice for transfusion therapy. 60. Patients with warm autoimmune hemolytic anemia (AIHA) due to a-methyldopa (Aldomet®) with hemoglobins of 8.5 g/dL or above Patients requiring transfusion with RBC6 1 that will not transmit cytomegalovirus (CMV) 62. Patients with normovolemic anemia 63. Patients who are thrombocytopenic secondary to the treatment of acute leukemia A. Platelet concentrate B. RBC C. Leukocyte-reduced RBC D. Transfusion not indicated

130. C. Anti-Lea, -Leb, and -Pl are antibodies that react at immediate spin (room temperature or below). Of these, Pj and Leb antigens are present on Cell #7, which shows negative reactivity. This makes these specificities unlikely to be present in the patient's serum. Lea antigen is present on Cells #3 and #8, both of which show a positive immediate-spin reaction. Anti-D is usually IgG and reacts best at 37°C and AHG phases of testing.

For questions 124-132, refer to red cell panel chart 3. In addition to red cell panel chart 3, use the following information to answer questions 129-132 130. The antibody that reacts at immediate spin is most likely A. Anti-D B. Anti-P1 C. Anti-Lea D. Anti-Leb

131. B. All the antibodies listed react at warm temperatures. The K antigen is present only on Cells #1 and #7 and is absent from Cells #2, #3, and #4 that reacted at 37°C and AHG phases of testing. Also, Anti-K and anti-k do not usually react without the addition of AHG. Anti-C and -D may react at 37°C without AHG, but usually only if albumin or enzymes are used as potentiators. Anti-C and -D are often found together. In this instance, however, there would be a positive reaction with Cell #5 if anti-C were present as well as anti-D.

For questions 124-132, refer to red cell panel chart 3. In addition to red cell panel chart 3, use the following information to answer questions 129-132 131. The antibody that reacts at 37°C and with AHG is A. Anti-C B. Anti-D C. Anti-CD D. Anti-K

132.D. A patient's red blood cells should be negative for the antigen corresponding to the antibody identified as long as the autocontrol is also negative. In this case, one already knows that the patient is group A, D-negative (does not have D antigen). A standard approach has been to require three antigen-positive cells that react and three antigen-negative cells that do not react for each antibody identified to establish probability that the antibody(ies) has (have) been correctly identified. There are only two Le(a+) donor cells on this panel. The anti-Lea reacts only at immediate spin and the anti-D does not. Presumably the screening cells have an additional Le(a+) cell. Because this antibody appeal's to be clinically insignificant, many would simply ignore it by eliminating the IS. At any rate, it would certainly not be necessary to run another panel.

For questions 124-132, refer to red cell panel chart 3. In addition to red cell panel chart 3, use the following information to answer questions 129-132 132. What should you do to increase the probability that an antibody identification is correct? A. Make an eluate. B. Do saliva testing. C. Run an additional panel. D. Type the patient's cells for the corresponding antigens.

(39:A, 40:D, 41:C, 42:C, 43:B) The storage temperature for whole blood, modified whole blood, RBCs, including leukocyte-reduced and deglycerolized products, is between 1 and 6°C. This range may be extended to 10°C during brief periods of transport. RBCs are frozen in a glycerol solution. These units must be stored at -65 °C or lower. Fresh-frozen plasma (FFP) and cryoprecipitate are stored at -18°C or colder with a 1-year expiration. Although this temperature meets AABB Standards, optimal storage temperature is -30°C or below. In fact, FFP expiration may be extended to 7 years if kept at -65 °C or lower. Frozen storage at low temperatures maintains optimum levels of the labile coagulation factors V and VIII in FFP and VIII in cryoprecipitate. Plasma should be frozen within 8 hours of collection when collected in CPD or CPDA-1. Platelet concentrates are stored at room temperature (20-24°C). They need to be agitated during storage.

For the following components prepared from whole blood (questions 39-43), indicate the required storage temperature. 39. Red blood cells (RBCs), liquid 40. Red blood cells, frozen 41. Fresh-frozen plasma 42. Cryoprecipitate 43. Platelet concentrate A. 1-6°C B. 20-24°C C. -18°C or colder D. -65°C or colder

(44:C, 45:D, 46:D, 47:A, 48:B) Whole blood and RBCs may be stored up to 35 days when collected in CPDA-1, as long as the hermetic seal remains unbroken. Adenine added to the anticoagulant increases the viability of the cells. Cells stored only in CPD have a shorter allow able storage of 21 days. Addition of adsol solution extends expiration of red blood cells to 42 days. Fresh-frozen plasma (FFP) and cryoprecipitate expire 12 months from the date of collection if stored at -18°C or colder. The expiration time for these components is based on the deterioration of the labile factor VIII. Units stored beyond 12 months may have reduced levels of factor VIII unless stored at much lower temperatures. FFP has been approved for 7-year storage if kept at -65 °C or lower. Once thawed, FFP expires in 24 hours when stored at 1-6°C. The type of plastic used in the manufacture of the bag affects the allowable storage time for platelets. The older type of bag (polyvinylchloride) does not allow as effective a gas exchange as the newer types of plastic. Platelet concentrates, prepared in PL-732 bags and stored at 20-24°C with agitation, expire 5 days from the date and time of collection.

For the following components prepared from whole blood (questions 44-48), indicate the shelf life. 44. Red blood cells in CPDA-1 45. Fresh-frozen plasma 46. Cryoprecipitate 47. Fresh-frozen plasma, thawed 48. Platelet concentrate in PL-732 (with agitation) A. 24 hours B. 5 days C. 35 days D. 1 year

(119:C, 120:A, 121:A, 122:D, 123:B) The Kell system has a number of antigens, among which is Kpa (Penney). This antigen has not been reported in blacks. The corresponding antibody is very rare because so few individuals have the antigen that stimulates its production. When it is present, it is not a serious problem because Kp(a-) blood is easily found. The McLeod phenotype is one in which all the Kell-associated antigens are expressed only weakly. McLeod cells are missing a precursor substance called Kx. Kx is coded for by a gene present on the X chromosome. Some of the male children afflicted with chronic granulomatous disease are of the McLeod phenotype, but exactly how the two are associated is not clear. The Ss locus is closely linked with the MN locus, and they are considered part of the same blood group system. M8 (Gilfeather) is a rare allele in the MN system. When the Mg antigen is present it can cause typing difficulties because it will not react with either anti-M or anti-N. Because the MN antigens are well developed at birth, they were often used in paternity testing. The presence of an M8M or M8N combination can look like a homozygous M or N, leading to a second-order (indirect) exclusion unless the red cells are tested with anti-M8. The presence of the Mg antigen on the red blood cells of the alleged father and child practically proves paternity. Currently, most paternity testing is done by DNA analysis, not by red cell antigen testing.

For the following items (questions 119-123), select the answer that most closely corresponds to the description. 119. Found predominantly in whites 120. Associated with weak Kell system antigenic expression 121. Associated with the presence of chronic granulomatous disease 122. Linked with MN 123. A rare allele of M and N A. McLeod phenotype B. MS C. Kpa D. Ss

(53:D, 54:A, 55:C, 56:D, 57:D, 58:D, 59:D) Donors may be accepted after age 17, provided all results of the physical examination are normal. There is no upper age limit. Elderly donors may participate in a blood program at the discretion of the local blood bank physician. Many senior citizens obtain written permission from their personal physicians and present approval at the time of donation. The interval between donation of blood for allogeneic transfusion is 8 weeks, or 56 days. This time period is designed to protect the health of the donor. Exceptions at the discretion of the blood bank and personal physician may be made if the blood is intended for autologous use. A man who had a history of sex with another man after 1977 must be indefinitely deferred because of the possibility of transmitting the HIV virus. A history of jaundice in the first days of life is indicative of hemolytic disease of the newborn and is not a cause for deferral. A mild skin rash caused by acne, poison ivy, psoriasis, or other allergies is not a cause for donor deferral, as long as the disorder does not extend into the antecubital area at the venipuncture site. Final acceptance or deferral may be made at the phlebotomist's discretion, dependent upon whether the arm can be properly prepared to maintain sterility of the product without undue discomfort to the donor. A woman who has been pregnant is deferred until 6 weeks following conclusion of the pregnancy unless her blood is needed for her infant and the donation is physician approved. The acceptable limits of the physical examination include: Temperature: 37.5°C (99.5°F) or less Pulse: 50-100 bpm Blood pressure: systolic ^180 mm Hg, diastolic<100mmHg Runners or other athletes may be accepted when the pulse rate is less than 50 bpm, as long as no irregularity in beats is detected. These parameters are incorporated in the AABB Standards for the safety of the donor and are in general use by all blood-collecting facilities. For donor suitabil ity, the FDA and AABB require only that the hemoglobin level be no less than 12.5 g/dL (with no sex differentiation) and that the temperature and blood pressure be within normal limits as determined by a qualified physician or by persons under his or her supervision.

For the following situations (questions 53—59), indicate whether the individual volunteering to donate blood for allogeneic transfusion should be accepted or deferred. Assume results of the physical examination to be acceptable unless noted. 53. A 65-year-old man whose birthday is tomorrow 54. A 45-year-old woman who donated a unit during a holiday appeal 54 days ago 55. A 50-year-old man who had sex with another man in 1980 56. A 25-year-old man who says he had yellow jaundice right after he was born 57. An 18-year-old with poison ivy on his hands and face 58. A woman who had a baby 2 months ago 59. A 35-year-old runner (pulse 46 bpm) A. Defer temporarily B. Defer for 12 months C. Defer indefinitely D. Accept

(49:A, 50:B, 51:C, 52:D) Blood cells continue to metabolize in vitro. Plasma glucose and ATP are depleted. Intermediary metabolites are generated. These may interfere with the production of energy via glycolysis. This results in a gradual loss of red blood cell viability. Storage at lowered temperatures (1-6°C) slows metabolism. ACD and CPD solutions contain sufficient glucose to support RBC viability for 21 days. CPDA-1 also contains adenine, which allows extension of the shelf life to 35 days. Adenine maintains viability by ATP regeneration. Red blood cells prepared with additive solutions such as AS-1 have a shelf life of 42 days. EDTA is not an approved solution for the storage of blood for transfusion.

Using the specified anticoagulant/preservative (questions 49-52), indicate the allowable shelf life for blood for transfusion therapy. 49. CPD (citrate phosphate dextrose) 50. CPDA-1 (citrate phosphate dextrose adenine) 51. AS-l(Adsol®) 52. EDTA A. 21 days B. 35 days C. 42 days D. Not an approved anticoagulant


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