Blood Groups & Serologic Testing Flashcards
1
Q
- A description of the antiglobulin test is:
a. IgG and C3d are required for RBC sensitization.
b. Human globulin is completely eluted from RBCs
during saline washings.
c. Human globulin is injected into an animal.
d. AHG reacts with human globulin molecules bound to
RBCs.
A
d. AHG reacts with human globulin molecules bound to
RBCs
2
Q
- Polyspecific AHG reagent contains:
a. Anti-IgG and anti-IgA.
b. Anti-IgG and anti-IgM.
c. Anti-IgG and anti-C3d.
d. Anti-IgA and Anti-C3d.
A
c. Anti-IgG and anti-C3d.
3
Q
- Monoclonal anti-C3d is:
a. Derived from one clone of plasma cells.
b. Derived from multiple clones of plasma cells.
c. Derived from immunization of rabbits.
d. Reactive with C3b and C3d.
A
a. Derived from one clone of plasma cells
4
Q
- Which of the following is a clinically significant
antibody whose detection has been reported in some
instances to be dependent on anticomplement activity in polyspecific AHG?
a. Anti-Jka
b. Anti-Lea
c. Anti-P1
d. Anti-H
A
a. Anti-Jka
5
Q
- After the addition of IgG-coated RBCs (check cells)
to a negative AHG reaction during an antibody
screen, a negative result is observed. Which of the
following is a correct interpretation based on these
findings?
a. The antibody screen is negative.
b. The antibody screen cannot be interpreted.
c. The saline washings were adequate.
d. AHG reagent was added.
A
b. The antibody screen cannot be interpreted.
6
Q
- RBCs must be washed in saline at least three times
before the addition of AHG reagent to:
a. Wash away any hemolyzed cells.
b. Remove traces of free serum globulins.
c. Neutralize any excess AHG reagent.
d. Increase the antibody binding to antigen
A
b. Remove traces of free serum globulins.
7
Q
- An in vivo phenomenon associated with a positive
DAT is:
a. Passive anti-D detected in the maternal sample.
b. Positive antibody screen tested by LISS.
c. Identification of alloantibody specificity using a
panel of reagent RBCs.
d. Maternal antibody coating fetal RBCs.
A
d. Maternal antibody coating fetal RBCs.
8
Q
- False-positive DAT results are most often associated
with:
a. Use of refrigerated, clotted blood samples in which
complement components coat RBCs in vitro.
b. A recipient of a recent transfusion manifesting an
immune response to recently transfused RBCs.
c. Presence of antispecies antibodies from administration of immune globulin (IVIG).
d. A positive autocontrol caused by polyagglutination
A
a. Use of refrigerated, clotted blood samples in which
complement components coat RBCs in vitro.
9
Q
- Polyethylene glycol (PEG) enhances antigen antibody reactions by:
a. Decreasing zeta potential.
b. Concentrating antibody by removing water.
c. Increasing antibody affinity for antigen.
d. Increasing antibody specificity for antigen.
A
b. Concentrating antibody by removing water.
10
Q
- Solid-phase antibody screening is based on:
a. Adherence.
b. Agglutination.
c. Hemolysis.
d. Precipitation.
A
a. Adherence.
11
Q
- A positive DAT may be found in which of the following
situations?
a. A weak D-positive patient
b. A patient with anti-M
c. HDFN
d. An incompatible crossmatch
A
c. HDFN
12
Q
- What do Coombs’ check cells consist of?
a. Type A-positive cells coated with anti-IgG
b. Type A-negative cells coated with anti-IgG
c. Type O-positive cells coated with anti-D
d. Type B-negative cells coated with anti-D
A
c. Type O-positive cells coated with anti-D
13
Q
- Which of the following IAT methods requires the use of
check cells?
a. Manual tube method with albumin
b. Gel
c. Automated solid-phase analyzer
d. Enzyme-linked
A
a. Manual tube method with albumin
14
Q
- Which uncontrollable factor can affect AHG testing?
a. Temperature
b. Antibody affinity
c. Gravitational force in the centrifuge
d. Incubation time
A
d. Incubation time
15
Q
- Which would be the most efficient method for a laboratory staffed by medical laboratory technicians?
a. LISS
b. Polybrene
c. Solid-phase or gel
d. Enzyme-linked
A
b. Polybrene
