BLOOD BANK ASCP STUDY GUIDE
COMPREHENSIVE REVIEW WITH SOLVED
SCENARIOS AND DETAILED ANSWERS ELITE
EDITION 2026
◉Which antibodies to a component of complement
are contained in the rabbit polyspecific antihuman
globulin reagent for detection of in vivo
sensitization?
A. Anti-IgG and anti-C3a
B. Anti-IgG and anti-C3d
C. Anti-IgG and anti-IgM
D. All of these options . Answer: In the DAT (direct antiglobulin test),
rabbit
polyspecific antisera contains both an anti-human IgG component and an
antibody against the C3d component of complement.
◉Acquired B antigens have been found in:
A. Bombay individuals
B. Group O persons
, C. All blood groups
D. Group A persons . Answer: D The acquired B phenomenon is only
seen in group A persons.
◉Blood is crossmatched on an A positive person with
a negative antibody screen. The patient received a
transfusion of A positive RBCs 3 years ago. The
donors chosen for crossmatch were A positive.
The crossmatch was run on the Ortho Provue and
yielded 3+ incompatibility. How can these results
be explained?
A. The patient has an antibody to a low-frequency
antigen
B. The patient has an antibody to a high-frequency
antigen
C. The patient is an A2 with anti-A1
D. The patient is an A1 with anti-A2 . Answer: C The patient is likely an
A2 with anti-A1 which is
causing reactivity in the crossmatch. A negative
antibody screen rules out the possibility of an
antibody to a high-frequency antigen, and two
donor units incompatible rules out an antibody to a low-frequency
antigen.
COMPREHENSIVE REVIEW WITH SOLVED
SCENARIOS AND DETAILED ANSWERS ELITE
EDITION 2026
◉Which antibodies to a component of complement
are contained in the rabbit polyspecific antihuman
globulin reagent for detection of in vivo
sensitization?
A. Anti-IgG and anti-C3a
B. Anti-IgG and anti-C3d
C. Anti-IgG and anti-IgM
D. All of these options . Answer: In the DAT (direct antiglobulin test),
rabbit
polyspecific antisera contains both an anti-human IgG component and an
antibody against the C3d component of complement.
◉Acquired B antigens have been found in:
A. Bombay individuals
B. Group O persons
, C. All blood groups
D. Group A persons . Answer: D The acquired B phenomenon is only
seen in group A persons.
◉Blood is crossmatched on an A positive person with
a negative antibody screen. The patient received a
transfusion of A positive RBCs 3 years ago. The
donors chosen for crossmatch were A positive.
The crossmatch was run on the Ortho Provue and
yielded 3+ incompatibility. How can these results
be explained?
A. The patient has an antibody to a low-frequency
antigen
B. The patient has an antibody to a high-frequency
antigen
C. The patient is an A2 with anti-A1
D. The patient is an A1 with anti-A2 . Answer: C The patient is likely an
A2 with anti-A1 which is
causing reactivity in the crossmatch. A negative
antibody screen rules out the possibility of an
antibody to a high-frequency antigen, and two
donor units incompatible rules out an antibody to a low-frequency
antigen.
