Hemolytic anemias

Question 1

warm agglutinin AIHA (autoimmune hemolytic anemia) etiology

Answer 1

drugs (penicillin),

viral infections

autoimmune (SLE)

immunodeficiency

lymphoproliferative like CLL

Question 2

warm agglutinin AIHA clinical presentation

Answer 2

asymptomatic to life threatening anemia direct coomb’s positive with anti IgG anti-C3 or both

Question 3

Treatment of warm agglutinin AIHA (autoimmune hemolytic anemia)

Answer 3

steroids

splenectomy in refractory cases

Question 4

complications of warm agglutinin AIHA

Answer 4

VTE, lymphoproliferative disorders

Question 5

etiology of cold agglutinin AIHA

Answer 5

infections (mycoplasma pneumoniae infection, infectious mononucleosis)

lymphoproliferative diseases

Question 6

clinical presentation of cold agglutinin AIHA

Answer 6

symptoms of anemia

livedo reticularis

acral cyanosis with cold exposure that disappear with warming

direct Coombs positive with anti C3 OR anti IgM but not IgG

Question 7

treatment of cold agglutinin AIHA

Answer 7

avoidance of cold temperatures even in warm weather

rituximab +/- fludarabine

not steroid responsive, don’t give antibiotics

Question 8

complications of cold agglutinin AIHA

Answer 8

ischemia,

peripheral gangrene

lymphoproliferative disorders

Question 9

findings of autoimmune hemolytic anemia (AIHA)

Answer 9

autoantibodies (can be either warm agglutinins IgG or cold agglutinins or IgM) destroying red blood cells

Question 10

what are lab findings of AIHA?

Answer 10

increased haptoglobulin,

decreased Hgb,

increased indirect bilirubin

increased LDH.

See spherocytosis on peripheral smear due to partial phagocytosis of IgG coated RBCs

see increased MCV due to reticulocytosis.

diagnosis is via positive direct antiglobulin (Coomb’s test)

Question 11

what causes pure red cell aplasia?

Answer 11

drugs, thymoma and parvo B19 infection. NOT AIHA.

Question 12

chart for AIHA

Answer 12

Question 13

G6PD deficiency is seen in

Answer 13

X linked disorder seen in Mediterranean and AA populations.

Occurs with TMP-SMX and due to a enzymatic disorder of RBCs and see oxidative stress that is caused by medications, favism, infections and metabolic abnormalities.

T

Question 14

what causes G6PD deficiency

Answer 14

Occurs with TMP-SMX and due to a enzymatic disorder of RBCs

and see oxidative stress that is caused by

medications (dapsone, antimalarials and sulfonamide abx)

favism (eating fava beans)

infections -

and metabolic abnormalities. - DKA

Question 15

When do G6PD pts present after stressful event?

Answer 15

2-4 days after a oxidatively stressful event and see evidence of hemolysis or a 3-4 g/dl drop in Hgb with rise in reticulocyte count

Question 16

Pathophysiology of G6PD and why we don’t see deficiency in G6PD during acute hemolysis

Answer 16

See drop in Hgb and rise in reticulocyte counts.

older deficient RBCs are replaced by younger cells which have sufficient G6PD enzyme activity to sustain further oxidative damage without hemolysis after the hemolysis event when older RBCs have hemolyzed due to stressful oxidative event.

Question 17

lab findings of G6PD

Answer 17

drop in Hgb. See elevated LDH, low haptoglobin, indirect bilirubin increased.

See bite cells on peripheral smear

Reticulocyte count is high and normal G6PD levels during acute episode

Negative DAT or direct and indirect Coomb’s test.

Question 18

when to check G6PD levels if one is suspected to have G6PD?

Answer 18

never check during acute hemolysis event. Check 2-3 months after hemolytic episode.

Question 19

pyruvate kinase deficiency

Answer 19

Second most common cause of enzyme deficient hemolytic anemia after G6PD.

PK patients don’t have hemolysis after oxidative stress. No characteristic morphological RBCs on peripheral smear.

Question 20

Bactrim can cause

Answer 20

hemolytic anemia in G6PD deficiency pts

Question 21

Treatment of cold hemolytic anemia and cold agglutinin’s dx

Answer 21

Treatment of hemolytic anemia and cold agluttin dx related to this is avoidance of cold (even in warm weather) and heavy socks and coats to prevent agluttination.

seen with mycoplasma pneumoniae or have an underlying EBV with 1 antibodies.

severe dx: need rituximab.

Question 22

transfusion related reactions chart

Answer 22

Question 23

unusual cause of hemolytic anemia

Answer 23

Wilson’s dx

check serum ceruloplasm

Question 24

elevated LFTs and hemolytic anemia in a young person

Answer 24

Wilson’s dx