Howard: Basic & Applied Concepts of Blood Banking and Transfusion
Practices, 4th Edition
Chapter 07: Other Red Cell Blood Group Systems, Human Leukocyte Antigens, and
Platelet Antigens
Critical Thinking Exercises
EXERCISE 7.1
The blood bank received a call requesting two units of “Kell-negative” RBCs for a patient with
anti-K.
1. Discuss why this request is incorrect.
2. What should the request have stated?
EXERCISE 7.2
List the red cell antibodies with serologic reactivity usually enhanced with enzyme-treated
panel cells.
EXERCISE 7.3
A patient has a history of the following alloantibodies: anti-S, anti-Leb, and anti-Jka.
1. Which of these antibodies are clinically significant?
2. How would you test for compatible RBC units?
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Critical Thinking Exercises
3. How would enzyme-treated panel cells react with this mixture of antibodies?
EXERCISE 7.4
A patient has a history of a previously identified autoanti-I. The current sample is
nonreactive with screening cells when tested at room temperature. What are the
implications of this result in a current request for the transfusion of two units of RBCs?
EXERCISE 7.5
Explain how you would differentiate a Donath-Landsteiner antibody from a cold
autoantibody.
EXERCISE 7.6
A prenatal sample contains the alloantibody, anti-Jsb.
1. Is this antibody clinically significant?
2. What is the most probable race of this patient?
3. What reagents would be helpful in the workup of this antibody?
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Critical Thinking Exercises
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EXERCISE 7.7
A physician requests phenotypically matched donor RBC units for a very young sickle cell
patient. The patient’s phenotype is D+, C−, E−, c+, e+, K+, S−, s+, M−, N+; Le(a−b−);
Fy(a−b−); Jk(a+b−).
1. Which donor population (race) would you test to find a close match?
2. Which antigens are not important to match because of the corresponding antibody’s
clinical significance?
EXERCISE 7.8
A patient has a phenotype of Le(a−b+).
1. Is this patient a secretor or a nonsecretor?
2. What genes are responsible for conferring Lea and Leb antigens on the red cells?
EXERCISE 7.9
A patient was admitted for surgery with a history of a previous anti-U. You are directed to
test this patient’s siblings because U-negative donor units are rare. No commercial
antiserum is available for testing. What other antisera could you use to determine the
phenotype of the patient’s siblings?
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Critical Thinking Exercises
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EXERCISE 7.10
1. Does a patient with an anti-Vel present a problem for provision of compatible donor
units?
2. How would Vel-negative units be located?
EXERCISE 7.11
What are the Xg blood group system phenotypes of the male and female offspring from the
mating of an Xg(a+) male and an Xg(a−) female?
EXERCISE 7.12
A patient who is not responding to platelet transfusions requires an HLA-matched platelet
transfusion. The patient’s HLA type is performed and is reported as A2, A11, B8, B35. A
donor is called with a compatible type to donate for this patient. Why were the class II
antigens not considered for matching?
EXERCISE 7.13
Parents of a kidney transplant candidate were tested for a potential compatible kidney because
the candidate demonstrated HLA antibodies. The patient’s HLA antigens were typed as A1, A2,
B27, B50, DR17, and DR11. Antibodies identified were specific for A3, B18, and DR7 antigens.
1. If the mother’s HLA typing is A1, A3, B35, B27, DR4, and DR11, and the father’s typing
is A2, A24, B50, B44, DR11, and DR17, what antigens did the father contribute?
Mother: A1, A3, B35, B27, DR4, DR11
Child (patient): A1, A2, B27, B50, DR17, DR11
Father: A2, A24, B50, B44, DR1, DR17
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Critical Thinking Exercises
2. List the probable HLA types of the candidate’s three siblings. Select the kidney or
kidneys with the best match.
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