Deck 12: Hemolytic Disease of the Fetus and Newborn

Question 1

Which of the following best describes the principle of the Kleihauer-Betke test?

A) Fetal hemoglobin is resistant to acid elution and remains in the cell to stain pink, whereas adult cells appear as ghost cells.
B) Adult hemoglobin is resistant to acid elution and remains in the cell to stain pink, whereas fetal cells appear as ghost cells.
C) D-positive cells from the fetus form rosettes around the IgG-coated mother's cells.
D) Indicator cells form rosettes around the fetal D-positive cells.

Answer 1

A
The Kleihauer-Betke acid elution test is a stain that enables the quantification of fetal cells in the maternal circulation.

Question 2

A large fetomaternal bleed in a D-negative woman who delivered a D-positive infant should be suspected if the:

A) direct antiglobulin test on the infant is positive.
B) infant is premature.
C) fetomaternal hemorrhage screen result is positive.
D) maternal antibody screen is positive postpartum.

Answer 2

C
The fetal screen determines whether the mother has received a significant amount of D-positive cells from the baby during birth.

Question 3

Anti-D in the serum of a third-trimester pregnant woman with a titer of 16 is indicative of:

A) the presence of Rh immune globulin administered at 28 weeks.
B) active immunization.
C) passive immunization.
D) None of the above

Answer 3

B
Antibody titers of 16 or more suggest active immunization and not the presence of anti-D from Rh immune globulin.

Question 4

To prevent graft-versus-host disease,red blood cells prepared for intrauterine transfusions should be:

A) frozen and deglycerolized.
B) saline washed.
C) ABO and D-compatible with the mother.
D) irradiated.

Question 5

Select the situation where the administration of Rh immune globulin would be contraindicated.

Question 6

Which one of the following antibodies is unlikely to cause hemolytic disease of the fetus and newborn?

A) Anti-C
B) Anti-K
C) Anti-Le^a
D) Anti-S

Question 7

A newborn phenotypes as group O,D-positive with a 1+ direct antiglobulin test.The mother's antibody screening test is negative.Assuming the antibody screen is valid; one should consider the reason for the positive DAT is due to an antibody against _______________ antigen.

A) D
B) A or B
C) low-incidence
D) high-incidence

Question 8

Select the most common antibody specificity associated with hemolytic disease of the fetus and newborn.

A) Anti-A,B
B) Anti-C
C) Anti-D
D) Anti-K

Question 9

A 300-µg dose of Rh immune globulin contains sufficient anti-D to protect against how much whole blood?

A) 25 mL
B) 30 mL
C) 50 mL
D) 100 mL

Question 10

Why is reverse grouping omitted in the neonatal period for ABO testing?

A) The maternal antibody is identical to that of the newborn.
B) Newborns do not produce their own antibody until about 4 months.
C) The newborn's antibody is the same as the paternal antibody.
D) None of the above is correct.

Question 11

Which tests are performed to identify the cause of suspected hemolytic disease of the fetus and newborn?

A) ABO group
B) D testing
C) Direct antiglobulin test
D) All of the above

Question 12

Following delivery,when should Rh immune globulin be administered?

A) 12 hours
B) 24 hours
C) 48 hours
D) 72 hours

Question 13

A group O,D-positive mother gave birth to a group A,D-negative infant.After 24 hours,the newborn's bilirubin level rose to 19 mg/dL.A direct antiglobulin test performed on the cord blood specimen was positive with anti-IgG.What antibody is most likely implicated?

A) Anti-D
B) Anti-A
C) Anti-B
D) Anti-A,B

Question 14

Which elution method is ideal in the investigation of ABO hemolytic disease of the fetus and newborn?

A) Glycine-acid
B) Lui freeze-thaw
C) Xylene
D) Chloroform

Question 15

All of the following are goals of an exchange transfusion except to:

A) correct anemia.
B) remove high levels of unconjugated bilirubin.
C) remove high levels of maternal antibody.
D) restore the platelet count.

Question 16

Select the true statement regarding ABO hemolytic disease of the fetus and newborn (HDFN).

A) It is frequently seen in group A mothers with group O infants.
B) It cannot occur during prima gravida (first pregnancy).
C) Bilirubin levels often exceed 15 mg/dL in the affected infants.
D) The frequency of ABO hemolytic disease of the fetus and newborn is greater than Rh hemolytic disease of the fetus and newborn.

Question 17

All of the following are common characteristics of ABO hemolytic disease of the fetus and newborn except:

A) weak positive direct antiglobulin test.
B) the mother is group A.
C) the antibody on the infant's cells is anti-A,B.
D) mild clinical symptoms.

Question 18

In testing amniotic fluid,the Liley method of predicting the severity of hemolytic disease of the fetus and newborn is based on:

A) colorimetric protein analysis.
B) optical density of bilirubin at 450 nm.
C) ratio of lecithin to sphingomyelin.
D) titration of antibody.

Question 19

Amniotic fluid analysis showed a marked increase into zone III of the Liley graph.Lecithin-sphingomyelin ratios indicated that the fetal lungs were not mature.Select the most appropriate decision regarding medical intervention.

A) No immediate need for intervention
B) An intrauterine transfusion
C) Delivery by cesarean section
D) None of the above

Question 20

The Kleihauer Betke test was performed using a 1-hour post-delivery maternal blood sample.
Results: 10 fetal cells/1000 cells counted
It is the policy to add 1 vial of Rh immune globulin to the calculated dose when the estimated volume of the hemorrhage exceeds 20 mL of whole blood.Calculate the number of vials of Rh immune globulin that would be indicated under these circumstances.

A) 2
B) 3
C) 4
D) 5

Question 21

Rh immune globulin contains:

A) IgG anti-D.
B) immune serum globulin.
C) IgM anti-D.
D) gamma globulin.

Question 22

To be considered a candidate for Rh immune globulin,the mother is ______________ and the infant is _____________.

A) D-positive, D-negative
B) D-negative, D-positive
C) D-negative, D-negative
D) D-positive, D-positive

Question 23

What type of hemolytic disease of the fetus and newborn affects the first-born?

A) ABO
B) D
C) E
D) M

Question 24

The rosette test will detect a fetomaternal hemorrhage as small as:

A) 5 mL
B) 10 mL
C) 15 mL
D) 20 mL

Question 25

In a suspected case of ABO HDFN,what significant information is obtained from the baby's blood smear?

A) The estimated platelet count
B) Increase in nucleated red cells
C) The presences of spherocytes
D) Increase in monocytes

Question 26

Which of the following is true regarding the rosette test?

A) The test is a staining procedure differentiating fetal and adult cells
B) The test is valid only if the mother is D-negative and the infant is D-positive.
C) Indicator cells bind to the D-positive maternal cells forming a rosette.
D) The test is a quantitative test to determine how many vials of Rh immune globulin to administer.

Question 27

What immunoglobulin is capable of crossing the placenta?

A) IgA
B) IgG
C) IgM
D) IgE

Question 28

A 0.3% fetomaternal bleed was determined by a Kleihauer-Betke stain of postpartum blood.What is the estimated volume of the fetomaternal bleed expressed as whole blood?

A) 10 mL
B) 15 mL
C) 20 mL
D) 25 mL

Question 29

During a first-trimester prenatal examination,a pregnant group A,D-negative woman had an anti-D titer of 8.What is the most likely course of action?

A) The anti-D is probably from prenatal Rh immune globulin; another dose should be given at birth.
B) Repeat the titer in 4 weeks to determine if significant rise in titer is detected.
C) The pregnancy is considered high risk, and the mother should be followed up immediately with amniocentesis or percutaneous umbilical cord testing.
D) None of the above is correct.

Question 30

A weakly reactive anti-D was detected in a sample from a D-negative mother one day following delivery of a D-negative baby.Based on these results,what is the next step?

A) Titer the anti-D
B) Perform a rosette test
C) Review records for prenatal RhIG administration
D) Administer RhIG