289b microangiopathic hemolytic anemia

Question 1

microangiopathic hemolytic anemia - pathogenesis? rbc appearance?

Answer 1

mechanical destruction of RBCs in circulation –> schistocytes w/ high LDH, low haptoglobin, anemia

Question 2

microangiopathic hemolytic anemia - causes?

Answer 2

TTP - thrombotic thrombocytopenic purpura

HUS - hemolytic uremic syndrome

DIC - disseminated intravascular coagulation

Question 3

Idiopathic/autoimmune thrombotic thrombocytopenic purpura (TTP) - pathogenesis?

Answer 3

autoantibodies –>

ADAMTS13 –>

large vWF –>

thrombus formation –>

low platelets, RBC shearing, impaired blood flow to organs –>

stroke, renal impairment, MI

Question 4

microangiopathic hemolytic anemia - TTP presentation?

Answer 4

Fever
Angiopathic anemia
Thrombocytopenia

Renal dysfunction
Neurologic abnormalities

“FAT RN”

Question 5

HUS - pathogenesis?

Answer 5

kids: enterohemorrhagic colitis –> bloody diarrhea

E Coli (O157:H7) –> Shiga like toxin –> endo damage –> thrombus –> thrombocytopenia + angiopathic anemia

can cause renal vascular damage –> renal dysfunction, may require dialysis

Question 6

HUS - rx?

Answer 6

no antibiotics –> makes worse

eculizumbad: monoclonal Ab –> complement factor 5 (sued in PNH)

Question 7

DIC

Answer 7

procoagulant in blood –> widespread thrombi –> uses up all coagulation factors + fibrinolysis (D-dimers) –> bleeding

Question 8

DIC

Answer 8

procoagulant in blood –> widespread thrombi –> uses up all coagulation factors + fibrinolysis (D-dimers) –> bleeding