Common Bleeding Disorders

ITP

TTP

HUS

DIC

Pathophys:

Autoimmune production of IgG against platelet antigens (glycoprotein IIb/IIIbA) leading to platelet destruction

Decreased activity of ADAMTS13 enzyme (normally cleaves vWF multimers) resulting in platelet aggregation/thrombocytopenia and RBC hemolysis

Due to endothelial damage by drugs or infection, classically seen following E. coli 0157:H7 infection from undercooked beef

Widespread activation of coagulation cascade with thrombi resulting in ischemia/infarction, the consumption of platelets/factors resulting in bleeding, and intitiation of fibrinolysis causing more bleeding

Clinical:

Petechial rash, epistaxis, gingival bleeding, menorrhagia

Skin/mucosal bleeding, fever, hemolytic anemia, CNS abnormalities (seizure, stroke, focal neuro deficits, etc.), acute renal injury

* CNS abnormalities: TTP>HUS

Skin/mucosal bleeding, fever, hemolytic anemia, CNS abnormalities (seizure, stroke, focal neuro deficits, etc.), acute renal injury, +/- diarrhea

* Renal abnormalities: HUS>TTP

Large degree of variation depending upon preciptating illness: predominate hypercoagulable vs predominate hyperfibrinolysis vs combination vs subclinical

Labs:

Low platelet count, Normal PT/PTT, Normal fibrinogen

Low platelet count, Normal PT/PTT, Normal fibrinogen, Hemolytic anemia

Low platelet count, Normal PT/PTT, Normal fibrinogen, Hemolytic anemia

Low platelet count, Increased PT/PTT, Decreased fibrinogen, Hemolytic Anemia

Treatment:

Corticosteroids, +/- IVIG, +/- platelet transfusion, splenectomy in refractory cases

Plasma exchange, FFP transfusion if delay in plasma exchange, +/- corticosteroids, avoid platelet transfusion

Supportive care, +/- plasma exchange and dialysis, avoid platelet transfusion

Find and treat underlying cause, +/- blood product transfusions as needed