mlt review set 3 -boc 2020
A.request a fresh specimen
A liquid stool specimen is collected at 10:00 pm and brought to the laboratory for culture and ova and parasite examination. It is refrigerated until 10:10 am the next day, when the physician requests that the technologist look for amoebic trophozoites. The best course of action would be to: A.request a fresh specimen B.perform a concentration on the original specimen C.perform a trichrome stain on the original specimen D.perform a saline wet mount on the original specimen Commentary References Protozoan trophozoites are fragile and begin to disintegrate as soon as they are passed. Liquid stool specimens should be preserved within 30 minutes of passage in order to adequately preserve parasite morphology. If a liquid specimen cannot be properly preserved, another specimen should be collected.
D.Pseudomonas aeruginosa
A nonfermenting Gram-negative bacilli is isolated from a wound. The nitrate and oxidase are strongly positive. The growth on Mueller-Hinton agar produces pyoverdin. The organism is: A.Burkholderia cepacia B.Moraxella lacunata C.Chryseobacterium (Flavobacterium) meningosepticum D.Pseudomonas aeruginosa Pseudomonas aeruginosa produces a blue-green pigment, reduces nitrate and is oxidae positive.
D.irradiated
A patient in the immediate post bone marrow transplant period has a hematocrit of 21%. The red cell product of choice for this patient would be: A.packed B.saline washed C.microaggregate filtered D.irradiated Bone marrow transplant patients are at risk for transfusion-associated graft-vs-host disease (TA-GVHD) and therefore should receive irradiated blood products.
D.mixed-field
A patient is group A, Rh-positive but is receiving a Group O, bone marrow transplant (BMT) on Friday. After the transplant, what hemagglutination pattern will the patient demonstrate when the patient's red cells are tested with anti-A? A.rouleaux B.aggregation C.polyagglutination D.mixed-field Commentary References 2 cell populations may lead to a mixed-field agglutination pattern. Mixed-field may occur from transfusion, stem cell transplant or rare genetic chimera. A chimera is a person with a dual population of cells derived from more than one zygote.
C.when there is a change in the medical director of the lab
A quality management system (QMS) is a system for designing, implementing, maintaining, and managing quality in a laboratory. A fundamental element of a QMS is training and competence assessment of testing personnel. Which of the following statements is false? Training is required: A.for newly hired, transferred or promoted personnel B.when new testing platforms are implemented C.when there is a change in the medical director of the lab D.when an employee demonstrates repeated performance issues Newly hired, transferred or promoted personnel, and employees who demonstrate repeated performance issues equire training under QMS, as well as when new testing platforms are implemented. A change in the medical director of the laboratory would not necessitate retraining of existing employees.
B.therapeutic
A sample is sent to the laboratory for an anti-Xa assay. The result of the PTT is 65.7 seconds. The result of the anti-Xa assay is 0.9 U/mL of heparin. The patient is on Lovenox®. Their anti-Xa level is: A.subtherapeutic B.therapeutic C.supratherapeutic D.prophylactic Commentary References The prophylactic range for LMWH is 0.2 to 0.5 U/mL, and the therapeutic range is 0.5 to 1.2 U/mL.
C.review the stained blood smear
A specimen analyzed on an automated hematology instrument has a platelet count of 19 × 103/µL (19 × 109/L). The first procedure to follow is: A.report the count after the batch run is completed B.request a new specimen C.review the stained blood smear D.notify the laboratory manager Commentary References Low platelet counts should be verified with a slide estimate.
D.cystic fibrosis
A sweat chloride >60 mEq/L (60 mmol/L) is indicative of: A.multiple sclerosis B.muscular dystrophy C.respiratory distress syndrome D.cystic fibrosis Commentary References Cystic fibrosis is a caused by a defective ion channel, which causes an accumulation of chloride in the sweat.
C.Edwardsiella spp.
A young girl cuts her foot on a rock while swimming at the ocean. Her foot begins to show signs of infection and her parents take her to the ER. A culture grows a non-lactose fermenting Gram-negative bacilli that produces copious amounts of hydrogen sulfide and gas, is indole positive and motile. The organism most likely isolated is: A.Shigella spp. B.Escherchia spp. C.Edwardsiella spp. D.Klebsiella spp. Commentary References Edwardsiella spp. are commonly isolated from reptiles and freshwater fish. Infections can occur during an aquatic accident resulting in an infected wound. Key biochemical characteristic is the production of hydrogen sulfide otherwise presents similarly to E. coli.
D.coefficient of variation
An index of precision is statistically known as the: A.median B.mean C.standard deviation D.coefficient of variation Commentary References Precision is the closeness of agreement among replicate measurements, or reproducibility. The coefficient of variation, a more useful measure of reproducibility, is the measure of relative random error expressed as a percentage.
A.growth at 42°C, pyocyanin production, gelatinase production
An organism has been identified as a member of the fluorescent group of Pseudomonas. Which of the following sets of tests should be used to determine the species of the organism? A.growth at 42°C, pyocyanin production, gelatinase production B.pyocyanin production, gelatinase production, OF glucose C.growth at 37°C, pyocyanin production, OF glucose D.gelatinase production, growth at 52°C, H2S Commentary References Growth at 42°C and pyocyanin production are classic tests for the identification of Pseudomonas aeruginosa. Gelatin hydrolysis separates Pseudomonas putida (negative) from Pseudomonas fluorescence (positive).
D.block H1 histamine receptors
Antihistamines like Benadryl®: A.depress IgE production B.block antigen binding to surface IgE C.bind histamine D.block H1 histamine receptors Commentary References Antihistamines block histamine binding to histamine receptors.
second antibody titer is at least 4x the first
Blood is drawn from a patient for serological tests for a viral disease shortly after the time of onset and again 4 weeks later. The results of the tests are considered diagnostic if the: A.first antibody titer is 2x the second B.first and second antibody titers are equal C.first antibody titer is 4x the second D.second antibody titer is at least 4x the first A 4-fold or greater increase in antibody titer from second of 2 serum specimens taken from a patient during the acute and convalescent phases of an infection is considered to be diagnostic.
C.lymphocytes
Cells that produce antibodies and lymphokines are: A.erythrocytes B.granulocytes C.lymphocytes D.thrombocytes Commentary References Lymphocyte function.
D.increase sensitivity of the antigen
Cholesterol is added to the antigen used in flocculation tests for syphilis to: A.destroy tissue impurities present in the alcoholic beef heart extract B.sensitize the sheep RBCs C.decrease specificity of the antigen D.increase sensitivity of the antigen Commentary References VDRL antigen contains 0.9% cholesterol.
B.monitoring the course of a known cancer
Clinical assays for tumor markers are most important for: A.screening for the presence of cancer B.monitoring the course of a known cancer C.confirming the absence of disease D.identifying patients at risk for cancer Commentary References Tumor markers are useful for monitoring therapy, detecting recurrence and aiding in prognosis of tumors, but are not useful for screening the general population for cancer or confirming the absence of disease They are not sensitive or specific enough for diagnosis but may aid in the diagnosis in that they are generally set up to be more sensitive than specific and indicate when more testing is needed. Tumor markers are used in conjunction with clinical information, histology results in diagnosis.
C.perform an elution and identify the antibody in the eluate
A patient is readmitted to the hospital with a hemoglobin level of 7 g/dL (70 g/L) 3 weeks after receiving 2 units of red cells. The initial serological tests are: ABORh A+ Antibody screen negative DAT 1+ mixed field Which test should be performed next? A.antibody identification panel on the patient's serum B.repeat the ABO type on the donor units C.perform an elution and identify the antibody in the eluate D.crossmatch the post reaction serum with the 2 donor units Lack of expected rise in hemoglobin after transfusion may be a sign of a delayed hemolytic transfusion reaction. If the DAT is positive, a repeat DAT using anti-IgG and anti-C3d reagents should be performed to determine if the patient's red cells are coated with IgG, C3d, or both. A positive anti-IgG result shows that an IgG antibody(ies) has sensitized the cells. An elution should be performed to remove and identify the antibody coating the transfused donor red cells. In this case, the antibody is not detectable in the antibody screen, so a routine cell panel on the serum would not be helpful. Since the transfusion occurred 3 weeks previously, donor samples are not available for testing.
C.acute phase reactant
A patient presents with an aPTT of 24 seconds (25 - 35 seconds) which is below the normal range. A possible explanation for this result is the presence of a(n): A.DVT B.lupus anticoagulant C.acute phase reactant D.inhibitor Several plasma proteins become elevated in acute phase reactions, including factor VIII, vWF, and fibrinogen. Elevations in any of these could result in a shortened aPTT. An elevation of a low value for vWF into the normal range may occur in an acute phase reaction, thus masking a diagnosis of von Willebrand disease. In this case, it would be helpful to measure fibrinogen to determine whether or not the patient is in an acute phase reaction at the time of testing.
A.many platelets are abnormally large
A platelet determination was performed on an automated instrument and a very low value was obtained. The platelets appeared adequate when estimated from the stained blood film. The best explanation for this discrepancy is: A.many platelets are abnormally large B.blood sample is hemolyzed C.white cell fragments are present in the blood D.red cell fragments are present in the blood Commentary References Instruments count particles within defined size limits. The upper limit is to separate large platelets from erythrocytes. Small or fragmented RBCs may be counted as platelets.
C.the antigen is electrophoresed and then monospecific antisera is reacted with it
In immunofixation electrophoresis: A.the antibody reacts with the antigen and then the complex is electrophoresed B.the antigen is electrophoresed into an antibody containing gel C.the antigen is electrophoresed and then monospecific antisera is reacted with it D.the antigen is electrophoresed, transferred to nitrocellulose and then antibody reacts with it and an EIA is performed Commentary References In immunoelectrophoresis, first the serum is separated in an agarose gel by electrophoresis, then in a trough that is cut parallel to the plane of the electrophoresis, antiserum is placed. The antibody diffuses toward the serum proteins and arcs of antibody antigen precipitation occur.
C.Crithidia luciliae
In the anti-double-stranded DNA procedure, the antigen most commonly utilized is: A.rat stomach tissue B.mouse kidney tissue C.Crithidia luciliae D.Toxoplasma gondii Commentary References The Crithidia substrate has giant mitochondrion containing native DNA that is free from contaminating histone antigens.
B.anti-Lea
In the process of identifying an antibody, the technologist observed 2+ reactions with 3 of the 10 cells in a panel after the immediate spin phase. There was no reactivity after incubation at 37°C and after the anti-human globulin test phase. The antibody most likely is: A.anti-P1 B.anti-Lea C.anti-C D.anti-Fya Commentary References Lewis antibodies are usually IgM and agglutinate saline suspended cells. Approximately 22% of the population is Le(a+), which would account for 3 out of 10 donor units being incompatible. Anti-P1 is also an antibody that may react at immediate spin, but 79% of the white population and 94% of the black population are P1+. Anti-C and anti-Fya are IgG antibodies that react at the antiglobulin phase.
C.2-year old pre-surgical patient
In what patient population may we observe the following results? AntiA 4+ AntiB 0 AntiD 4+ A cell 0 B cell 1+ A.labor and delivery patient B.30-year old GI bleed patient C.2-year old pre-surgical patient D.16-year old ACL repair surgery patient ABO antibodies are not present at birth. ABO antibodies develop in response to the environment from 3-6 months of age and continue to increase in titer until achieving adult levels at 5-10 years of age.
D.primary myelofibrosis
In which of the following disease states are teardrop cells and abnormal platelets most characteristically seen? A.hemolytic anemia B.multiple myeloma C.G6PD deficiency D.primary myelofibrosis Commentary References RBC morphology; disease state identification.
B.AF2 is most likely the father of the child.
The results of STR typing of a child, the child's mother and 3 alleged fathers (AF) of the child are listed in the table below. Which of the statements below is correct concerning the alleged fathers? A.AF1 is most likely the father of the child. B.AF2 is most likely the father of the child. C.AF3 is most likely the father of the child. D.none of the alleged fathers is likely the father of the child Commentary References AF2 could possibly have contributed all of the alleles inherited by the child after the alleles the child inherited from the mother have been considered.
C.avidity
The strength of a visible reaction is known as: A.prozone reaction B.absorption C.avidity D.elution Commentary References Describes the overall interaction of an antibody with its antigen.
.expected for anti-DNA antibodies
The technologist observes apparent homogenous staining of the nucleus of interphase cells while performing an IFA-ANA, as well as staining of the chromosomes in mitotic cells. This result is: A.indicative of 2 antibodies, which should be separately reported after titration B.expected for anti-DNA antibodies C.inconsistent; the test should be reported with new reagent D.expected for anti-centromere antibodies Commentary References Homogeneous pattern may indicate the presence of anti-DNA antibodies for both single- or double-stranded DNA.
D.the presence of a cast matrix
To distinguish between a clump of WBCs and a WBC cast, it is important to observe: A.the presence of free-floating WBCs B.a positive leukocyte reaction C.a positive nitrite reaction D.the presence of a cast matrix Commentary References White blood cells are often attached to the cast matrix as well as being imbedded in the matrix. White blood cells frequently occur in clumps and could can resemble a cast, but no cast matrix is observed. WBC casts indicate a more serious tubular infection, whereas WBC clumps can be seen in cystitis.
B.porphyrins
Urine from a 50-year-old man was noted to turn dark red on standing. This change is caused by the presence of: A.glucose B.porphyrins C.urochrome D.creatinine Commentary References The 2 pigments are porphyrin and urochrome. Urochrome is "urine color," which is yellow. Porphyrin is red.
B.TRALI
Use of only male donors as a source of plasma intended for transfusion is advocated to reduce which type of reaction? A.allergic B.TRALI C.hemolytic D.TACO (circulatory overload) Commentary References TRALI is most commonly caused by donor HLA or granulocyte-specific antibodies (human neutrophil antibodies, HNA) that react with recipient antigens, causing damage to the lung basement membrane and bilateral pulmonary edema within 6 hours of transfusion. Multiparous females are more likely to have antibodies than males. Using male donors as the sole source of plasma products is a strategy for reducing the risk of TRALI.
D.expiration date and, if applicable, expiration time of the blood product
Which of the following must be verified in the transfusion service prior to the issue of blood products? A.antibody detection test result B.date and time when the patient's blood sample was drawn C.name of the transfusionist administering the blood product D.expiration date and, if applicable, expiration time of the blood product Commentary References Release of blood components for patient transfusion requires verification by blood bank professional of 2 independent patient identifiers, (ie, patient name and identification number), ABO group and Rh type, the donor unit's ABO group and Rh type, donation identification number, expiration date (if applicable, time), results of the crossmatch interpretation and time and date of the unit release.
C.analytical errors are not obvious to providers
Which of the following statements about analytical errors is true? A.analytical laboratory errors are easy for ordering providers to detect B.analytical errors almost never happen in a CLIA accredited laboratory C.analytical errors are not obvious to providers D.analytical errors can be caused by poor patient preparation Commentary References Providers are completely dependent on the laboratory for the detection and correction of analytical errors.
C.HLA-DR, HLA-DQ and HLA-DP are all Class II
Which of the following statements is true about Class II HLA antigens? A.they are found on the surface of most nucleated cells. B.Bg antigens are part of HLA Class II C.HLA-DR, HLA-DQ and HLA-DP are all Class II D.they are only located on neurons and platelets Commentary References HLA-DR, HLA-DQ and HLA-DP are Class II antigens which are only found on monocytes, macrophages, B lymphocytes, dendritic cells, early hematopoietic cells and intestinal epithelial cells.
B.fresher units (generally <7 days) should be issued
Which of the following statements regarding red cell transfusion to infants less than 4 months old is correct? A.only phenotype identical units should be issued B.fresher units (generally <7 days) should be issued C.irradiated blood components are contraindicated D.crossmatching with a current sample is required for each transfusion Commentary References For infants < 4 months old, red cell units should be, in general, <7 days old to have optimal 2,3, DPG levels to facilitate O2 delivery to the tissues. Fresher units will also minimize the amount of K+ ions transfused to the infant.
A.bacterial contamination
Which of the following transfusion reactions is characterized by high fever, shock, hemoglobinuria, DIC and renal failure? A.bacterial contamination B.circulatory overload C.febrile D.anaphylactic Commentary References In septic transfusion reactions, patients can experience fever >101°F (38.3°C), hypotension and chills with shaking. In severe reactions, patients can have shock, hemoglobinuria, renal failure, and DIC.
pH
Which of the following would be affected by allowing a urine specimen to remain at room temperature for 3 hours before analysis? A.occult blood B.specific gravity C.pH D.protein Commentary References Consider whether a substance can increase or decrease outside the body. No more blood can be produced. Although the RBC may rupture, they will still make a positive result on a biochemical strip. The amount of solutes won't change, so specific gravity won't change. pH is affected by metabolism of the urine components by bacteria, and room temperature is warm enough for this to occur. Protein will not increase or decrease.
D.Jk(a-b-)
Which phenotype could not result from the mating of a Jk(a+b+) female and a Jk(a-b+) male? A.Jk(a+b-) B.Jk(a+b+) C.Jk(a-b+) D.Jk(a-b-) Commentary References This is an example of autosomal codominant inheritance. The female will pass either Jkaor Jkb. The male is Jkb Jkb or JkJkb.The resulting offspring cannot be negative for both Jkaand Jkb antigens.
C.ELISA
Which test has the greatest sensitivity for antigen detection? A.precipitin B.agglutination C.ELISA D.complement fixation Commentary References ELISA is a solid phase immunoassay that uses anti-immunoglobulins that are labeled with an enzyme that can be detected by the appearance of color on the addition of a substrate.
A.skin test for commonly encountered antigens
Which test is used to evaluate the cellular immune system in a patient? A.skin test for commonly encountered antigens B.determination of isohemagglutinin titer C.immunoelectrophoresis of serum D.measurement of anti-HBsAg after immunization Commentary References Skin tests are used to determine whether the delayed type hypersensitivity response mediated by T cells is functioning properly. All other tests listed evaluate humoral antibody responses.
A.MALDI-TOF
Which testing platform meets this description? An isolated colony is irradiated by a laser, which ionizes the biomolecules and causes them to become accelerated in an electric field. The ionized biomolecules then enter a flight tube where they are separated by their mass-to-charge ratio. A.MALDI-TOF B.multiplex PCR C.pulsed-field gel electrophoresis D.sequencing Commentary References MALDI-TOF is not a molecular application. It is a mass spectrometry platform. The other choices are molecular based, and distractor c also incorporates electrophoresis.
C.calcium pyrophosphate dihydrate
ynovial fluid from a 68-year-old male reveals rhombic crystals with weak positive birefringence when viewed using polarizing microscopy. These crystals can be identified as: A.cholesterol B.monosodium urate C.calcium pyrophosphate dihydrate D.hydroxyapatite Commentary References Calcium pyrophosphate dihydrate (CPPD) crystals can be distinguished from monosodium urate (MSU) crystals based on key characteristics. CPPD crystals are rodlike or rhombic in shape and have weak positive birefringence under polarizing microscopy while MSU appear as fine, needle-like crystals that have strong negative birefringence.
C.fungal meningitis
Results from a WBC differential performed on CSF from an adult patient suspected of having meningitis are listed below: Seg 3% lymph 62% mono 23% eosin 12% These results are highly suggestive of: A.bacterial meningitis B.viral meningitis C.fungal meningitis D.tubercular meningitis Commentary References Eosinophil pleocytosis (≥10%) may be associated with parasitic or fungal infections or an allergic reaction to intracranial shunts or intrathecal injections of foreign substances.
B.CSF-VDRL
he serological test for syphilis recommended for detecting antibody in cerebrospinal fluid is: A.non-treponemal antibody B.CSF-VDRL C.FTA-ABS D.MHA-TP Commentary References The VDRL test is the only serological test recommended for testing of spinal fluid because of the low incidence of false-positives.
D.clean and reload the hemocytometer
n undiluted CSF specimen is loaded onto a Neubauer hemocytometer and the following results are recorded after counting all nine 1.0 mm2 quadrants on both sides: Side1 100cells Side2 50cells The laboratorian should: A.report the average WBC/µL from side 1 and 2 B.report the difference in WBC/µL from side 1 and side 2 C.report the sum of WBC/µL from side 1 and 2 D.clean and reload the hemocytometer Commentary References After the cell count is performed for each side/chamber of the hemocytometer, the values are compared and must agree with each other within 20%. If the counts have a difference greater than 20%, the hemocytometer should be cleaned with 70% alcohol, dried and reloaded with a well-mixed specimen for a new count to be performed.
A.paroxysmal cold hemoglobinuria (PCH)
A 10-year-old girl was hospitalized because her urine had a distinct red color. The patient had recently recovered from an upper respiratory infection and appeared very pale and lethargic. Tests were performed with the following results: HGB 5g/dL reticulocyte 15% DAT weak reactivity with polyspecific and neg for c3d and IGg Antibody screen negative Donath lansteiner test positive p cell no hemolysis The patient probably has: A.paroxysmal cold hemoglobinuria (PCH) B.paroxysmal nocturnal hemoglobinuria (PNH) C.warm autoimmune hemolytic anemia D.hereditary erythroblastic multinuclearity with a positive acidified serum test (HEMPAS) The Donath-Landsteiner test is diagnostic for PCH. The antibody is IgG and is biphasic: hemolysis occurs when the antibody is incubated with cells and cold temperatures and then incubated at 37°C. Often the antibody demonstrates specificity towards the high-incidence antigen P (not to be confused with P1). The antibody screen is usually negative and the patient's red cells are coated with complement.
A.bile solubility, optochin sensitivity
A 15-year-old is admitted to the ER with severe sinusitis. Aspiration specimens from the nasal passage reveal a pure culture of alpha-hemolytic, depressed center colonies with a distinctive mucoid appearance on a blood agar plate. Gram stains of the colonies are shown below: Which of the following could aid in the identification of the organism recovered? A.bile solubility, optochin sensitivity B.hippurate hydrolysis, bile esculin C.bacitracin sensitivity, Lancefield grouping D.PYR positive, catalase negative Commentary References Colony morphology and Gram stain characteristics are 2 of the first indicators that an organism may be Streptococcus pneumoniae. Susceptibility to optochin and a positive bile solubility test indicating the organism's ability to be autolytic both definitively identify S. pneumoniae.
B.ketones
A 17-year-old girl decided to go on a starvation diet. After 1 week of starving herself, what substance would most likely be found in her urine? A.protein B.ketones C.glucose D.blood Commentary References Ketones are byproducts of fat metabolism. During low carbohydrate or starvation diets, ketones can be found in the urine.
B.thyroid-stimulating hormone (TSH)
A 2-year-old child with a decreased serum T4 is described as being somewhat dwarfed, stocky, overweight, and having coarse features. Of the following, the most informative additional laboratory test would be the serum: A.thyroxine-binding globulin (TBG) B.thyroid-stimulating hormone (TSH) C.triiodothyronine (T3) D.cholesterol Commentary References Congenital hypothyroidism presents with very low thyroid hormones and is best confirmed by serum TSH.
D.result d
A 50-year-old patient was found to have the lab results in Figure 1. It was determined that the patient was suffering from pernicious anemia. Which of the results in Figure 2 was most likely obtained from the same patient? A.result a B.result b C.result c D.result d Commentary References Pernicious anemia results in pancytopenia.
B.Moraxella catarrhalis
A Gram stain performed on a sinus aspirate revealed Gram-negative diplococci within PMNs. Oxidase testing is positive and carbohydrate degradation tests are inert. The organism most likely is: A.Neisseria lactamica B.Moraxella catarrhalis C.Neisseria meningitidis D.Neisseria sicca Commentary References The Neisseria species listed all ferment several carbohydrates, Moraxella catarrhalis is biochemically inert and does not ferment carbohydrates.
Alternaria sp.
A dematiaceous mold grew in 4 days on Sabouraud agar, isolated from a foot wound. The image shows chaining macroconidia with longitudinal and horizontal septations. The most likely identification is: A.Alternaria B.Curvularia C.Paecilomyces D.Scopulariopsis Commentary References Alternaria and Curvularia are dematiaceous, while c and d are brightly colored molds. Curvularia macroconidia are multi-celled and crescent shaped.
A.relative lymphocytosis
A leukocyte count and differential on a 40-year-old Caucasian man revealed: WBC 5.4 x 10^9/L Seg 20% Lymph 58% Mono 20% Eosino 2% This represents: A.relative lymphocytosis B.absolute lymphocytosis C.relative neutrophilia D.leukopenia Reference interval for percent lymphocytes indicates a relative lymphocytosis.
A.abscess
Acceptable specimen sources for culture of anaerobic bacteria includes: A.abscess B.stool C.clean catch urine D.vaginal Commentary References Anaerobes normally inhabit skin and mucous membranes as part of the normal flora. Distractors b and d are virtually always unacceptable for anaerobic culture, because they normally contain anaerobic organisms. Only suprapubic bladder aspiration is an appropriate urine specimen for anaerobes. It is difficult to interpret culture results from these specimens and distinguish between pathogens and normal flora.
D.thoroughly wash the wound with soap and water
After an accidental needle stick with a contaminated needle, the first action should be to: A.apply antiseptic ointment to the wound B.seek immediate medical assistance C.bandage the wound D.thoroughly wash the wound with soap and water Commentary References The correct answer is d, thoroughly wash the wound with soap and water. The other distractors are secondary, not primary actions.
B.direct agglutination procedure
An agglutination test wherein the antigen is a natural component of the infectious entity is a(n) A.indirect agglutination procedure B.direct agglutination procedure C.passive agglutination procedure D.reverse passive agglutination procedure Commentary References A direct agglutination procedure employs and entity with a naturally occurring antigen to which a host may build antibody. An example is in ABO blood group testing, wherein a host's red cells have naturally occurring antigens.
B.viral hepatitis
Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) are both elevated in which of the following diseases? A.muscular dystrophy B.viral hepatitis C.pulmonary emboli D.infectious mononucleosis Commentary References The transferases, alanine aminotransferase (ALT) and AST are located primarily in the liver. Elevated serum levels of the enzymes are seen in hepatocellular disorders. The levels may be 100 times the upper limit of normal. The ALT level is usually higher than AST. Increased levels of AST are also seen in infectious mononucleosis and muscular dystrophy, but ALT is not elevated in the clinical disorders.
is indicated for fibrinogen deficiencies
Cryoprecipitated AHF: A.is indicated for fibrinogen deficiencies B.should be stored at 4°C prior to administration C.will not transmit hepatitis B virus D.is indicated for the treatment of hemophilia B Commentary References Cryoprecipitate is used primarily for fibrinogen replacement. It is stored at room temperature (20 - 24°C) after thawing and must be infused within 6 hours as single units or if pooled using a sterile connecting device. If pooled in an open system, it must be infused within 4 hours.
C.myelomonocytic
Cytochemical stains were performed on bone marrow smears from an acute leukemia patient. The majority of the blasts showed varying amounts of myeloperoxidase positivity. Some of the blasts stained positive for chloroacetate esterase, some were positive for alpha-naphthyl acetate esterase, and some blasts stained positive for both esterases. What type of leukemia is indicated? A.lymphocytic B.myelogenous C.myelomonocytic D.erythroleukemia Commentary References Cytochemical results in acute myelomonocytic leukemia
D.febrile
Fever and chills are symptoms of which of the following transfusion reactions? A.citrate toxicity B.circulatory overload C.allergic D.febrile Commentary References Febrile nonhemolytic transfusion reactions are defined as fever of 1°C or greater (over baseline temperature) during or after transfusion, with no other reason for the elevation than transfusion, and no evidence of hemolysis in the transfusion reaction investigation. Patients often exhibit chills. Allergic reactions, citrate toxicity, and circulatory overload are not characterized by fever or chills.
B.HEPA
Filters generally used in biological safety cabinets to protect the laboratory worker from particulates and aerosols generated by microbiology manipulations are: A.fiberglass B.HEPA C.APTA D.charcoal Commentary References Microbiological hazards are contained using a biological safety cabinet with the air exhausting through a HEPA filter.
D.an approved safety can
Flammable and combustible liquids in containers ≥5 gallons should be stored in: A.a flammable safety cabinet vented to room air B.a nonexplosion proof refrigerator C.a fume hood D.an approved safety can Commentary References The correct answer is d, approved safety can. For distractor a, flammable safety cabinets should not be vented to room air. For distractor b, flammable and combustible liquids that require refrigeration are only to be stored in an explosion-proof refrigerator. For distractor c, hazardous substances, particularly of that volume, are not to be stored in a fume hood.
B.alkaline and dilute
Ghost red blood cells are seen in urine that is: A.acidic and dilute B.alkaline and dilute C.acidic and concentrated D.alkaline and concentrated Commentary References RBCs absorb water when in dilute urine, and are also less preserved in alkaline urine. Therefore, as the cells swell in the alkaline urine, the cell membrane allows hemoglobin to leak from the cell, resulting in the empty cell membrane and the pale appearance.
D.thyroid disease
High titers of anti-thyroid antibodies are most often found in: A.rheumatoid arthritis B.systemic lupus erythematosus C.chronic hepatitis D.thyroid disease Commentary References TPO (thyroid peroxidase) is the microsomal antigen of the thyroid epithelial cell. TPO antibodies are positive for about 90% of patients with chronic thyroiditis.
C.they are usually polymicrobic
In general, anaerobic infections differ from aerobic infections in which one of the following? A.they usually respond favorably to aminoglycoside therapy B.they usually arise from exogenous sources C.they are usually polymicrobic D.Gram stains of specimens are less helpful in diagnosis Commentary References Most infections involving anaerobes are polymicrobic and can include obligate aerobes, facultative anaerobes, microaerophilic bacteria in addition to anaerobic bacteria.
A.increase in CO2 content and pCO2 with a decreased pH
Respiratory acidosis is described as a(n): A.increase in CO2 content and pCO2 with a decreased pH B.decrease in CO2 content with an increased pH C.increase in CO2 content with an increased pH D.decrease in CO2 content and pCO2 with a decreased pH Commentary References Definition of respiratory acidosis.
B.decreased RBC band 3 protein
Laboratory findings in hereditary spherocytosis include: A.decreased WBCs B.decreased RBC band 3 protein C.reticulocytopenia D.positive direct antiglobulin test Commentary References The band 3 reduction test (also called the eosin-5-maleimide binding test or EMA) is a more sensitive flow cytometric procedure for confirming hereditary spherocytosis.
cea
Measurement of which of the following tumor markers may be useful in evaluating both pleural and peritoneal effusions for malignancy? A.CEA B.AFP C.hCG D.CA 125 Commentary References Measurement of carcinoembryonic antigen (CEA) may be useful in evaluating pleural and peritoneal effusions from patients with previous history of or suspected to have a CEA-producing tumor.
D.formaldehyde may be produced
Middlebrook 7H10 and 7H11 media must be refrigerated in the dark, and incubated in the dark as well. If these conditions are not met, the media may prove toxic for mycobacteria because: A.carbon dioxide will be released B.growth factors will be broken down C.light destroys the ammonium sulfate D.formaldehyde may be produced Commentary References If exposed to light, agar-based media such as Middlebrook 7H10 and 7H11 may release formaldehyde, which is toxic to mycobacteria.
B.HBeAg
The antigen marker most closely associated with transmissibility of HBV infection is: A.HBsAg B.HBeAg C.HBcAg D.HBV Commentary References HBeAg is present in patient serum during periods of active HBV replication, and is therefore a marker of high infectivity.
C.myocardial infarction
Myoglobinuria is most likely to be noted in urine specimens from patients with which of the following disorders? A.hemolytic anemia B.lower urinary tract infection C.myocardial infarction D.paroxysmal nocturnal hemoglobinuria Commentary References Myoglobin is a product of muscle destruction. Myocardial infarctions damage the heart muscle.
C.water, urea and sodium chloride
Normal urine primarily consists of: A.water, protein and sodium B.water, urea and protein C.water, urea and sodium chloride D.water, urea and bilirubin Commentary References Normal plasma constituents that can be filtered by the glomerulus are water, urea and sodium chloride. Protein molecules are too large to normally pass the glomerulus. Bilirubin is not a normal constituent of plasma.
D.repeat the control
On initial start-up of the automated hematology analyzer, one of the controls is slightly below the range for the MCV. Which of the following is indicated? A.call for service B.adjust the MCV up slightly C.shut down the instrument D.repeat the control Repeat of one out-of-range control is the first appropriate course of action.
C.perianal itching
Refer to the following image: The egg depicted above is most likely to be found in children suffering from: A.diarrhea B.constipation C.perianal itching D.stomach pain Commentary References The most common sign of Enterobius vermicularis infection is intense perianal itching.
A.Borrelia recurrentis
Relapsing fever in humans is caused by: A.Borrelia recurrentis B.Brucella abortus C.Leptospira interrogans D.Spirillum minus Commentary References Relapsing fever is caused by Borrelia recurrentis and is transmitted by the human body louse. Relapsing fever is characterized by the acute onset of high fever lasting 3 - 7 days, interspersed with periods of no fever lasting days to weeks.
D.Duffy
Resistance to malaria is best associated with which of the following blood groups? A.Rh B.I/i C.P D.Duffy Commentary References The Duffy glycoprotein on red cells is a receptor for the malarial parasite Plasmodium vivax. Red cells with the phenotype Fy(a-b-) are resistant to invasion by P. vivax.
A.natural
Skin, lactic acid in sweat, pH balance, mucous, and the motion of cilia represent which type of immunity? A.natural B.acquired C.adaptive D.auto he list of components in the stem are all naturally occurring and do not require the activation of the immune system to be present or functional.
complement inhibition
Symptoms associated with the effects of rheumatoid factor include all the following EXCEPT: A.joint inflammation B.immune complex deposition C.capillary endothelial space widening D.complement inhibition Commentary References Rheumatoid factor (RF) can stimulate complement cascade; it does not inhibit it.
D.TRALI
Symptoms of dyspnea, hypoxemia, and pulmonary edema within 6 hours of transfusion is most likely which type of reaction? A.anaphylactic B.hemolytic C.febrile D.TRALI Commentary References Noncardiogenic pulmonary edema, dyspnea, hypotension, and hypoxemia occurring within 6 hours of transfusion are clinical symptoms of TRALI.
C.Regan-Lowe agar
The best medium for culture of Bordetella pertussis is: A.phenylethyl alcohol agar B.potassium tellurite blood agar C.Regan-Lowe agar D.Tinsdale agar Commentary References Regan-Lowe agar is an enriched and selective medium formulated for the isolation of Bordatella pertussis. Cephalexin is added to inhibit nasopharyngeal flora. It provides better isolation of B. pertussis than Bordet-Gengou medium. Phenylethyl alcohol agar is selective for Gram-positive cocci. Potassium tellurite agar and Tinsdale agar are selective/differential media useful in isolating Corynebacterium diphtheriae.
alcohol reagents in the second method cause precipitation of proteins and increased background turbidity
Ten heparinized plasma samples were assayed for bilirubin by Jendrassik-Grof method on analyzer 1, and by the Evelyn-Malloy method on analyzer 2, in a method comparison study. The results were all 10 - 20% higher from analyzer 2 most likely because: A.the caffeine-benzoate stabilizer in the 2nd analyzer prevented falsely decreased results as found in analyzer 1 B.fibrinogen in the plasma samples caused falsely decreased results in the Jendrassik-Grof method C.alcohol reagents in the second method cause precipitation of proteins and increased background turbidity D.hemolysis caused greater interference in method 1 than in method 2 Commentary References Specimens and interference in bilirubin methods.
B.decreased serum iron levels
The anemia of chronic infection is characterized by: A.decreased iron stores in the reticuloendothelial system B.decreased serum iron levels C.macrocytic erythrocytes D.increased serum iron binding capacity Commentary References Low serum Fe levels due to role of hepcidin.
B.infectious mononucleosis
The cells seen in the image below are most consistent with: A.chronic myelogenous leukemia B.infectious mononucleosis C.acute lymphocytic leukemia D.Sézary syndrome Commentary References Morphology, recognition of reactive lymphocytosis.
C.nephelometry
The measurement of light scattered by particles in the sample is the principle of: A.spectrophotometry B.fluorometry C.nephelometry D.atomic absorption Commentary References Nephelometric methods are based upon light scatter being proportional to the number of particles in suspension, such as antigen-antibody complexes, which are physically larger than uncomplexed molecules.
maternal
The mode of inheritance of mitochondrial DNA is: A.dominant B.recessive C.codominant D.maternal Commentary References All mitochondria are passed on from a mother to her children, but not by a father to his children.
A.sodium hypochlorite
The most effective disinfectant recommended for bloodborne pathogens is: A.sodium hypochlorite B.isopropyl alcohol C.chlorhexidine gluconate D.povidone-iodine Commentary References The correct answer is a, sodium hypochlorite, which is a disinfectant. The other distractors are antiseptics, not disinfectants.
A.kallikrein
The most potent plasminogen activator in the contact phase of coagulation is: A.kallikrein B.streptokinase C.HMWK D.fibrinogen Commentary References A clot is degraded by plasmin in the fibrinolytic system. Plasminogen is the zymogen produced when factor XIIa and kallikrein are produced by contact activation.
A.a high carbohydrate diet for 3 days
The preparation of a patient for standard glucose tolerance testing should include: A.a high carbohydrate diet for 3 days B.a low carbohydrate diet for 3 days C.fasting for 48 hours prior to testing D.bed rest for 3 days Commentary References GTT diet preparation.
B.2:1
The ratio of kappa to lambda light chain-producing cells in normal individuals is: A.1:1 B.2:1 C.3:1 D.4:1 Commentary References The immunoglobulin molecule is made up of one or more units (# of units depending on heavy chain type) composed of 2 heavy chains and 2 light chains. The light chains can be either the kappa or lambda type. About 65% of the human immunoglobulin molecules have kappa chains and 35% have lambda chains.
A.an IgA-deficient patient with a history of transfusion-associated anaphylaxis
Washed Red Blood Cells are indicated in which of the following situations? A.an IgA-deficient patient with a history of transfusion-associated anaphylaxis B.a pregnant woman with a history of hemolytic disease of the newborn C.a patient with a positive DAT and red cell autoantibody D.a newborn with a hematocrit of <30% Commentary References Patients with IgA deficiency who have had anaphylactic transfusion reactions should receive washed RBCs. Anaphylactic reactions are typically caused by anti-IgA in the recipient. Washing removes plasma IgA from the donor unit.
clonal stem cell defect
What accounts for the majority of cases of sideroblastic anemia? A.clonal stem cell defect B.medications C.alcohol D.irradiation Commentary References Acquired types of sideroblastic anemia are more common than hereditary forms. Acquired idiopathic sideroblastic anemia results from stem cell disorders and is included in a group of conditions called the myelodysplastic syndromes.
D.single-stranded
What is the conformation of DNA at 95°C? A.double-stranded B.fragmented C.hairpin loop D.single-stranded Commentary References At temperatures above 80°C, the physical structure of DNA is changed, due to "melting" of the double-helical DNA. Melting is the disruption of noncovalent interactions including hydrogen bonding and base stacking.
A.anterior mediastinal mass
What is the most common presentation of precursor T-ALL? A.anterior mediastinal mass B.bone marrow involvement/cytopenias C.cervical lymphadenopathy D.dermal lymphatic infiltrates Commentary References Precursor T-ALL usually presents with a high WBC count and often a mediastinal mass.
D.Mycobacterium scrofulaceum
When grown in the dark, yellow to orange pigmentation of the colonies is usually demonstrated by: A.Mycobacterium tuberculosis B.Mycobacterium kansasii C.Mycobacterium fortuitum group D.Mycobacterium scrofulaceum Commentary References Mycobacterium scrofulaceum is a scotochromogen, which produces carotene pigment when grown in the light or dark.
C.single use and disposable gloves
When processing patient blood specimens and handling other potentially infectious material, the best choice of gloves is: A.reusable utility gloves B.latex gloves only C.single use and disposable gloves D.cut-resistant gloves Commentary References The correct answer is c, single use and disposable gloves. For distractor a, reusable utility gloves are not ideal or the best choice, but could be used if properly decontaminated after use and inspected for punctures or tears prior to reuse. Latex gloves should be avoided because of potential sensitization to the latex and the development of a latex allergy.
D.radiographic contrast media
When using the sulfosalicylic acid test, false-positive protein results may occur in the presence of: A.ketones B.alkali C.glucose D.radiographic contrast media Commentary References Radiographic dye will precipitate in SSA.
B.glomerulonephritis, rheumatic fever
Which 2 diseases are usually preceded by infection with beta-hemolytic streptococci? A.rheumatic fever, undulant fever B.glomerulonephritis, rheumatic fever C.rheumatic fever, tularemia D.glomerulonephritis, undulant fever Commentary References Noninfectious sequelae associated with infection with Streptococcus pyogenes are glomerulonephritis and rheumatic fever.
D.Trichuris trichiura
Which nematode produces eggs with characteristic hyaline polar plugs at each end? A.Ascaris lumbricoides B.Necator americanus C.Strongyloides stercoralis D.Trichuris trichiura Commentary References Trichuris, the whipworm, produces barrel-shaped eggs that have"plugs" or thickenings on each end. It may co-infect with Ascaris.
A.megakaryocyte
Which of the following cells is the largest cell in the bone marrow: A.megakaryocyte B.histiocyte C.osteoblast D.mast cell Commentary References Megakaryocytes are the largest cell in the bone marrow.
C.tyrosine
Which of the following crystals is seen in an amber urine with a positive bilirubin? A.ammonium biurate B.cystine C.tyrosine D.uric acid Commentary References Urinary crystals associated with liver disorders include bilirubin, tyrosine, and leucine.
A.C1q
Which of the following is the "recognition unit" in the classical complement pathway? A.C1q B.C3a C.C4 D.C5 Commentary References Complement C1q is the recognition piece.
