Deck 16: Hemolytic Anemia: Immune Anemias

Question 1

A patient is admitted with chest pain and extreme shortness of breath.Patient history is unremarkable except for ingestion of oral cefoxitin for the past 4 days.A DAT profile is positive with polyspecific AHG, negative with anti-IgG, and positive with anti-C3.The hemoglobin is 8.0 gm/dl.Based on these results, what mechanism of drug-induced hemolysis is present?

A)Immune complex
B)Autoantibody
C)Drug adsorption
D)Membrane modification

Answer 1

Immune complex

Question 2

Which of the following antibody specificities is associated with PCH?

A)Anti-I
B)Anti-Lea
C)Anti-P
D)Anti-D

Answer 2

Anti-P

Question 3

Presence of alloantibody can be demonstrated by performing what test?

A)Antibody screen
B)Agglutination in saline
C)Direct antiglobulin test
D)Indirect antiglobulin test

Answer 3

Antibody screen

Question 4

Acute hemolytic transfusion reaction is characterized by which of the following?

A)Extravascular hemolysis
B)Gastrointestinal hemorrhage
C)Intravascular hemolysis
D)Thrombosis

Question 5

2-14 days after a transfusion, a patient is cross-matched for another transfusion.Slight hemolysis and a positive DAT are found.What testing should follow?

A)Urine hemoglobin
B)An elution procedure
C)Plasma-free hemoglobin test
D)Bilirubin measurement

Question 6

Which of the following pairs of mother and fetus show the most likely potential for initiating HDFN in the fetus? $\begin{array}{cc}\text { Mother }& \text { Fetus } \\ \hline \text {a. Group A, Rh positive}& \text { Group O, Rh positive }\\ \text {b. Group B, Rh negative}& \text { Group O, Rh positive }\\ \text {c. Group AB, Rh positive}& \text { Group A, Rh negative }\\ \text {d. Group A, Rh negative}& \text { Group A B, R h negative }\\\end{array}$

Question 7

Paroxysmal cold hemoglobinuria is associated with viral and bacterial infections in children.With what other disease(s) is it associated?

A)Lymphoproliferative diseases in adults
B)Mixed-type AIHA
C)CAD
D)Warm autoimmune hemolytic anemia

Question 8

Which of the following conditions is NOT paired with the correct autoantibody?

A)Infectious mononucleosis / autoanti-i
B)WAIHA / autoanti-K
C)CAD / autoanti-I
D)PCH / autoanti-P

Question 9

A 44 year old female presents for her routine examination.She complains of tiredness and difficulty in breathing when she exerts herself.Her DAT is positive with polyspecific AHG and anti-IgG.Her hemoglobin is 7.5 gm/dl and her indices suggest a normocytic, normochromic anemia.Her peripheral blood smear shows the presence of spherocytes.What is the most likely diagnosis?

A)CAD
B)Drug-induced IHA
C)WAIHA
D)Mixed-type AIHA

Question 10

Which of the following is consistent with a diagnosis of CAD?

A)MCHC 44 g/dL
B)DAT positive with polyspecific AHG and anti-IgG
C)Spherocytes on the peripheral blood smear
D)MCV 104 fL

Question 11

Which of the following is an example of an anemia that occurs as a result of antibody development to an antigen that the individual lacks?

A)Autoimmune hemolytic anemia
B)Mixed-type autoimmune hemolytic anemia
C)Drug-induced hemolysis
D)Hemolytic disease of the newborn

Question 12

ABO incompatibility is associated with which type of transfusion reaction?

A)Immediate
B)Delayed
C)TRALI
D)Anaphylactic

Question 13

Autoantibodies associated with CAD are directed against what antigen system?

A)ABO
B)I
C)Rh
D)P

Question 14

A sample demonstrates a DAT profile that is positive with polyspecific AHG, negative with anti-IgG, and positive with anti-C3.If the Donath-Landsteiner test was also positive, what should the CLS do?

A)Perform an elution and antibody panel
B)Confer with the supervisor regarding the possibility of PCH
C)Request a serum sample for antibody screen
D)Perform a cold agglutinin test

Question 15

The most likely cause of immediate hemolytic transfusion reaction is due to antibodies of which system?

A)Kidd
B)Rh
C)ABO
D)I

Question 16

Which of the following set of results is consistent with a diagnosis of WAIHA?
$\begin{array}{ll}\text { Polyspecific AHG }&\text { anti-IgG } & \text { anti-C3 } \\\text {a. Positive}&\text { positive } & \text { negative } \\\text {b. Positive}&\text { negative } & \text { negative } \\\text {c. Negative}&\text { positive } & \text { positive } \\\text {d. Positive}&\text { negative } & \text { positive }\end{array}$

Question 17

Paroxysmal cold hemoglobinuria is confirmed by a positive:

A)Antibody class IgM.
B)Thermal amplitude of antibody over 20°C.
C)Donath-Landsteiner test .
D)Cold agglutinin test.

Question 18

Cold hemolytic anemia is usually due to:

A)Presence of an IgD antibody.
B)Presence of an IgG antibody.
C)Presence of an IgM antibody.
D)Presence of an IgG1 antibody.

Question 19

The absence of spherocytes on the peripheral blood smear in a case of suspected HDFN usually indicates that which of the following is the most likely cause of the condition?

A)ABO HDFN
B)Splenic hypertrophy
C)Rh HDFN
D)HDFN due to other blood group antibodies

Question 20

Which of the following will have the greatest effect on the rate of hemolysis in immune hemolytic anemia?

A)Presence of IgG2 on the erythrocyte
B)A limited number of antigens
C)Antibody that reacts at 37° C
D)Presence of IgM antibody

Question 21

Compare the differences in the activation of complement that lead to intravascular hemolysis or extravascular hemolysis.

Question 22

Compare the three mechanisms of drug-induced immune hemolysis.

Question 23

A Group O, Rh negative woman with no evidence of antibodies delivers her first child who shows a slightly decreased hemoglobin and the presence of spherocytes on the peripheral blood film.The DAT is positive with polyspecific AHG and anti-IgG.The baby is Group A, Rh negative and is slightly jaundiced with a bilirubin of 2.1 mg/dl.What is the most likely cause of the baby's jaundice?

A)Normal physiologic jaundice
B)Rh HDFN
C)ABO HDFN
D)Other type HDFN

Question 24

A patient on α-methyldopa may develop a type of drug-induced immune hemolysis that mimics what condition?

A)WAIHA
B)PCH
C)Immediate transfusion reaction
D)Delayed transfusion reaction

Question 25

A newborn is left at the Emergency Department.The baby appears lethargic and slightly jaundiced.Laboratory work on the baby shows a positive DAT with polyspecific AHG and with anti-IgG.The hemoglobin is 7.3 gm/dl and the peripheral blood smear shows marked polychromasia, macrocytosis and increased numbers of nucleated RBCs.The bilirubin is 4.4 mg/dl.What do you suspect is the underlying cause of these results?

A)ABO HDFN
B)Autoantibody from the mother in baby's circulation
C)Normal postnatal findings for a newborn
D)Rh HDFN

Question 26

During transfusion a patient developed pain in the area of the needle, shortness of breath, and chest tightness.What is the most likely cause?

A)Heart attack
B)Acute hemolytic transfusion reaction
C)TRALI
D)Anaphylacatic transfusion reaction

Question 27

Mixed-type AIHA is typically characterized by autoantibodies of which classes?

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

Question 28

A patient with SLE shows evidence of decreased hemoglobin and ongoing hemolysis.The DAT is negative.Which of the following is the most likely explanation for these results?

A)The subclass of IgG is not recognized by the polyspecific AHG.
B)The thermal amplitude of the antibody is <37°C.
C)High does IVIG used in treatment is interfering with the binding of AHG.
D)There is insufficient IgG for detection.

Question 29

Explain why the DAT profile in CAD is reactive only with polyspecific AHG and anti-C3 but not with anti-IgG.

Question 30

A patient's hemoglobin went from a value of 13.0 gm/dl after transfusion to 10.6 gm/dl 3 days after transfusion.What is the most likely type of transfusion reaction?

A)Allergic
B)TRALI
C)HLA-mediated
D)Delayed