BB Flashcards
(151 cards)
The key structural difference that distinguishes immunoglobulin subclasses is the:
A. Number of domains
B. Stereometry of the hypervariable region
C. The sequence of the constant regions
D. Covalent linkage of the light chains
C. The sequence of the constant regions
Immunoglobulin classes are differentiated according to the molecular structure of:
A. Light chains
B. Heavy chains
C. Fab fragment
D. Fc fragment
B. Heavy chains
A 54-year-old female previous smoker presents with a recent history of fever, swollen joints, and morning stiffness.
• Laboratory results indicate elevated C-reactive protein, positive cyclic citrullinated peptide of 205 units (cut-off: 20 units), speckled ANA pattern (titer 1:320), and negative rheumatoid factor.
What is the most likely diagnosis?
A. Reactive arthritis
B. Rheumatoid arthritis
C. Systemic sclerosis
D. Sjogren syndrome
B. Rheumatoid arthritis
Which of the following is used for the confirmation of infection with HIV-1?
A. Western blot (immunoblot) assay
B. ELISA
C. Complement fixation
D. p24 Antigen testing
A. Western blot (immunoblot) assay
Which technique is used for the confirmation of infection with HIV-1 and HIV-2?
A. Western blot (immunoblot) assay
B. ELISA
C. FDA-approved NAT
D. p24 Antigen testing
C. FDA-approved NAT
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
B. Monitoring the course of a known cancer
In general, in which of the following situations is the analysis of a tumor marker most useful?
A. Testing for recurrence
B. Prognosis
C. Screening
D. Diagnosis
A. Testing for recurrence
The chemical composition of an antibody is:
A. Protein
B. Lipid
C. Carbohydrate
D. Glycoprotein
D. Glycoprotein
What is the most common clinical incident that results in alloantibody production?
A. Viral infection
B. Solid tumor
C. Red cell transfusion
D. Autoimmune disease
C. Red cell transfusion
What antibodies are present in polyspecific AHG reagent?
A. Anti-IgG
B. Anti-IgM and anti-1gG
C. Anti-IgG and anti-C3d
D. Anti-C3d
C. Anti-IgG and anti-C3d
Which of the following medications is most likely to cause production of AUTOANTIBODIES?
A. Penicillin
B. Cephalosporin
C. Methyldopa
D. Tetracycline
C. Methyldopa
Red cells from a recently transfused patient were DAT positive when tested with anti-lgG. Screen cells and a panel performed on a patient’s serum showed very weak reactions with inconclusive results. What procedure could help to identify the antibody?
A. Elution followed by a panel on the eluate
B. Adsorption followed by a panel on the adsorbed serum
C. Enzyme panel
D. Antigen typing the patient’s red cells
A. Elution followed by a panel on the eluate
The procedure that removes intact antibodies from the red cell membranes is:
A. Autoadsorption
B. Enzyme pretreatment
C. Neutralization
D. Elution
D. Elution
A 56-year-old female with cold agglutinin disease has a positive direct antiglobulin test (DAT). When the DAT is repeated using monospecific antiglobulin sera, which of the following is most likely to be detected?
A. IgM
B. IgG
C. C3d
D. C4a
C. C3d
A crossmatch is positive at AHG phase with polyspecific AHG reagent but is negative with
monospecific anti-lgG AHG reagent. This may indicate the antibody:
A. Is a weak anti-D
B. Is a clinically insignificant Lewis antibody
C. Can cause decreased survival of transfused RBCs
D. Is a Duffy antibody
B. Is a clinically insignificant Lewis antibody
Crossmatch results at the antiglobulin phase were negative.
When 1 drop of check cells was added, NO AGGLUTINATION was seen. The most likely explanation is that the:
A. Red cells were overwashed
B. Residual patient serum inactivated the AHG reagent
C. Centrifuge speed was set too high
D. Laboratorian did not add enough check cells
B. Residual patient serum inactivated the AHG reagent
Autoantibodies demonstrating blood group specificity in warm autoimmune hemolytic anemia are associated
more often with which blood group system?
A. Rh
B. I
C. P
D. Fy
A. Rh
Which antibody is frequently seen in patients with
warm autoimmune hemolytic anemia?
A. Anti-Jka
B. Anti-e
C. Anti-K
D. Anti-Fy®
B. Anti-e
Many enhancement media used in the blood bank promote hemagglutination in the presence of IgG antibodies by reducing which of the following?
A. Hydrophilic forces
B. Low ionic potential
C. van der Waals forces
D. Zeta potential
D. Zeta potential
Low ionic strength saline (LISS) acts as an enhancement medium and facilitates antibody uptake by:
A. Activating complement
B. Increasing flexibility in hinge region
C. Removing water molecules
D. Reducing zeta potential
D. Reducing zeta potential
Which antibody would not be detected by group
O screening cells?
A. Anti-N
B. Anti-A1
C. Anti-Dia
D. Anti-k
B. Anti-A1
Screening cells, major crossmatch, and patient autocontrol are positive in all phases. Identify the problem.
A. Specific cold alloantibody
B. Specific cold autoantibody
C. Abnormal protein or nonspecific autoantibody
D. Cold and warm alloantibody mixture
C. Abnormal protein or nonspecific autoantibody
What corrective action should be taken when rouleaux causes positive test results?
A. Perform a saline replacement technique
B. Perform an autoabsorption
C. Run a panel
D. Perform an elution
A. Perform a saline replacement technique
Screening cells and major crossmatch are positive on IS only, and the autocontrol is negative. Identify the problem.
A. Cold alloantibody
B. Cold autoantibody
C. Abnormal protein
D. Antibody mixture
A. Cold alloantibody