Immunohematology-Hemolytic Disease of the Newborn (HDN) Flashcards
1
Q
- All of the following are reasons for a positive DAT
on cord blood cells of a newborn except:
A. High concentrations of Wharton’s jelly on cord
cells
B. Immune anti-A from an O mother on the cells
of an A baby
C. Immune anti-D from an Rh negative mother on
the cells of an Rh-positive baby
D. Immune anti-K from an K-negative mother on
the cells of a K-negative baby
A
D. Immune anti-K from an K-negative mother on
the cells of a K-negative baby
2
Q
- A fetal screen yielded negative results on a mother
who is O negative and infant who is O positive.
What course of action should be taken?
A. Perform a Kleihauer–Betke test
B. Issue one full dose of RhIg
C. Perform a DAT on the infant
D. Perform an antibody screen on the mother
A
B. Issue one full dose of RhIg
3
Q
- What should be done when a woman who is
24 weeks pregnant has a positive antibody screen?
A. Perform an antibody identification panel; titer if
necessary
B. No need to do anything until 30 weeks gestation
C. Administer Rh immune globulin (RhIg)
D. Adsorb the antibody onto antigen-positive cells
A
A. Perform an antibody identification panel; titer if
necessary
4
Q
- All of the following are interventions for fetal
distress caused by maternal antibodies attacking
fetal cells except:
A. Intrauterine transfusion
B. Plasmapheresis on the mother
C. Transfusion of antigen-positive cells to the
mother
D. Early induction of labor
A
C. Transfusion of antigen-positive cells to the
mother
5
Q
- Cord cells are washed six times with saline and the
DAT and negative control are still positive. What
should be done next?
A. Obtain a heelstick sample
B. Record the DAT as positive
C. Obtain another cord sample
D. Perform an elution on the cord cells
A
A. Obtain a heelstick sample
6
Q
- What can be done if HDN is caused by maternal
anti-K?
A. Give Kell immune globulin
B. Monitor the mother’s antibody level
C. Prevent formation of K-positive cells in the
fetus
D. Not a problem; anti-K is not known to
cause HDN
A
B. Monitor the mother’s antibody level
7
Q
- Should an O-negative mother receive RhIg if a
positive DAT on the newborn is caused by
immune anti-A?
A. No, the mother is not a candidate for RhIg
because of the positive DAT
B. Yes, if the baby’s type is Rh negative
C. Yes, if the baby’s type is Rh positive
D. No, the baby’s problem is unrelated to
Rh blood group antibodies
A
C. Yes, if the baby’s type is Rh positive
8
Q
- Should an A-negative woman who has just had a
miscarriage receive RhIg?
A. Yes, but only if she does not have evidence of
active Anti-D
B. No, the type of the baby is unknown
C. Yes, but only a minidose regardless of trimester
D. No, RhIg is given for term pregnancies only
A
A. Yes, but only if she does not have evidence of
active Anti-D
9
Q
- SITUATION: The Ortho Provue reports a type
on a woman who is 6 weeks pregnant with
vaginal bleeding as O negative. The woman
tells the emergency department physician she is
O positive and presents a blood donor card. The
medical laboratory scientist performs a test for
weak D and observes a 1+ reaction in AHG
phase. A Kleihauer–Betke test is negative. Is
this woman a candidate for RhIg?
A. No, she is Rh positive
B. Yes, she is a genetic weak D
C. No, there is no evidence of a fetal bleed
D. Yes, based upon the Provue results
A
A. No, she is Rh positive
10
Q
- Which of the following patients would be a
candidate for RhIg?
A. B-positive mother; B-negative baby; first
pregnancy; no anti-D in mother
B. O-negative mother; A-positive baby; second
pregnancy; no anti-D in mother
C. A-negative mother; O-negative baby; fourth
pregnancy; anti-D in mother
D. AB-negative mother; B-positive baby; second
pregnancy; anti-D in mother
A
B. O-negative mother; A-positive baby; second
pregnancy; no anti-D in mother
11
Q
- A Kleihauer–Betke acid elution test identifies
40 fetal cells in 2,000 maternal red cells. How
many full doses of RhIg are indicated?
A. 1
B. 2
C. 3
D. 4
A
D. 4
12
Q
- Kernicterus is caused by the effects of:
A. Anemia
B. Unconjugated bilirubin
C. Antibody specificity
D. Antibody titer
A
B. Unconjugated bilirubin
13
Q
- Anti-E is detected in the serum of a woman in
the first trimester of pregnancy. The first titer for
anti-E is 32. Two weeks later, the antibody titer is
64 and then 128 after another 2 weeks. Clinically,
there are beginning signs of fetal distress. What
may be done?
A. Induce labor for early delivery
B. Perform plasmapheresis to remove anti-E from
the mother
C. Administer RhIg to the mother
D. Perform an intrauterine transfusion using
E-negative cells
A
B. Perform plasmapheresis to remove anti-E from
the mother
14
Q
- What testing is done for exchange transfusion
when the mother’s serum contains an
alloantibody?
A. Crossmatch and antibody screen
B. ABO, Rh, antibody screen, and crossmatch
C. ABO, Rh, antibody screen
D. ABO and Rh only
A
B. ABO, Rh, antibody screen, and crossmatch
15
Q
- Which blood type may be transfused to an
AB-positive baby who has HDN caused by
anti-D?
A. AB negative, CMV negative, Hgb S negative;
irradiated or O negative, CMV negative,
Hgb S negative
B. AB positive, CMV negative; irradiated or O
positive, CMV negative
C. AB negative only
D. O negative only
A
A. AB negative, CMV negative, Hgb S negative;
irradiated or O negative, CMV negative,
Hgb S negative
