Deck 19: Hemolytic Anemia: Immune Anemias

Question 1

Autoantibodies associated with CAD are directed against which antigen system?

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

Answer 1

I

Question 2

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

Answer 2

Hemolytic disease of the newborn

Question 3

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 from other blood group antibodies

Answer 3

ABO HDFN

Question 4

Which of the following pairs of mother and fetus shows the most likely potential for initiating HDFN in the fetus?
Mother Fetus

A)Group A,Rh positiveGroup O,Rh positive
B)Group B,Rh negativeGroup O,Rh positive
C)Group AB,Rh positiveGroup A,Rh negative
D)Group A,Rh negativeGroup AB,Rh negative

Question 5

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

Question 6

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)Elution procedure
C)Plasma-free hemoglobin test
D)Bilirubin measurement

Question 7

What test can demonstrate the presence of alloantibody?

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

Question 8

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 9

ABO incompatibility is associated with which type of transfusion reaction?

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

Question 10

Which of the following set of results is consistent with a diagnosis of WAIHA?

Question 11

Which of the following characterizes acute hemolytic transfusion reaction?

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

Question 12

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 13

Which of the following antibody specificities is associated with PCH?

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

Question 14

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

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

Question 15

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 16

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 17

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

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

Question 18

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 clinical laboratory professional 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 19

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 20

Cold hemolytic anemia is usually caused by the presence of an:

A)IgD antibody.
B)IgG antibody.
C)IgM antibody.
D)IgG1 antibody.

Question 21

A newborn is left at a hospital emergency department.The baby appears lethargic and slightly jaundiced.Laboratory work on the baby shows a positive DAT with polyspecific AHG and anti-IgG.The hemoglobin is 7.3 gm/dl,and the peripheral blood smear shows marked polychromasia,macrocytosis,and an increased number 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 22

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

Question 23

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-dose IVIG used in treatment is interfering with the binding of AHG.
D)There is insufficient IgG for detection.

Question 24

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 25

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

Question 26

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

Question 27

A patient on α-methyldopa could 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 28

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 29

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)Anaphylactic transfusion reaction

Question 30

Compare the three mechanisms of drug-induced immune hemolysis.