Molecular Diagnostics 2024
1. A patient with multiple myeloma has the following reactions in the
ABO typing:
Anti-A= w+
Anti-B = w+
Anti-A,B = w+
Auto control = w+
A1 Cells = 4+
B cells = 4+
What is probably causing these results?
A. Rouleaux
B. Subgroup of A
C. Patient has hypogammaglobulinemia
D. Patient has selective IgA deficiency ✔️✔️correct answer-A
2. An antibody screen utilizing polyethylene glycol (PEG) was performed.
Reaction readings of this antibody screen are analyzed after immediate
spin and again at 37°C incubation with subsequent centrifugation. How
will the centrifugation of the tubes affect the patient's results?
A. Reactions will be enhanced
B. No effect will be seen
C. False positives may be seen
D. False negatives may be seen ✔️✔️correct answer-C
3. What must be true for the antiglobulin phase of the serologic
crossmatch to be omitted (i.e., immediate spin crossmatch is done)?
,A. The antibody screen must be negative and there is not history of
detection of unexpected antibodies.
B. The patient has not been transfused within the past 24 hours.
C. The blood is needed for surgery.
D. There is a history of detection of unexpected antibodies but the
current antibody screen is negative. ✔️✔️correct answer-A
4. Which of the following accurately represents reverse typing?
A. Reverse typing is performed using known reagent antisera to detect
ABO antigens on the patient's red blood cells.
B. Reverse typing is performed using known reagent red blood cells to
detect ABO antibodies in the patient's serum or plasma.
C. Reverse typing is performed using known reagent screening cells to
detect clinically significant antibodies in the patient's serum or plasma.
D. Reverse typing is performed using known reagent antisera to
phenotype donor red blood cells for clinically significant antigens.
✔️✔️correct answer-B
5. A former patient had an anti-E four years ago, but her antibody panel
is now negative. Since she now needs blood for surgery, what should the
blood bank do?
A. Get autologous blood from relatives.
B. Crossmatch E-negative units.
C. Give group O negative whole blood.
D. Give random compatible units. ✔️✔️correct answer-B
6. What is the maximum interval during which a recipient sample may be
used for compatibility testing if the patient has recently been transfused
or was pregnant within the past 3 months?
, A. 24 hours
B. 3 days
C. One week
D. Two weeks ✔️✔️correct answer-B
7. A patient transfused with two units of packed cells spiked a fever of
99.5oF and complained of chills five days after transfusion. The direct
antiglobulin test (DAT) was positive with anti-IgG, but negative with
anti-C3d. Compatibility testing was performed on the pre- and post-
transfusion specimens. The post-transfusion specimen was incompatible
with one of the donor units transfused. An antibody screen was done on
both the pre- and post-transfusion specimens. An antibody was
detected in the post-transfusion specimen only and identified by panel
studies as anti-Jka. This transfusion reaction is most:
A. Post-transfusion purpura
B. An anaphylactic response
C. An acute hemolytic transfusion reaction
D. A delayed hemolytic transfusion reaction ✔️✔️correct answer-D
8.You perform a gel ABO/Rh test on a 45-year-old male patient and you
obtain the following results.
Anti-A - 4+
Anti-B - 4+
Anti-D - 4+
D control - negative
A1 cells - 2+
B cells - 0
What could be the Type/Rh of this patient?
a. AB POS