Internal Medicine

0521779407-10 CUNY1086/Karliner 0 521 77940 7 June 6, 2007 17:44

862 Intravascular, Non-immune Hemolytic Anemia

■fever, pallor, jaundice, edema, nausea/vomiting, bloody diarrhea,

abdominal pain, hypertension, purpura, petechiae, bleeding, hep-

atosplenomegaly

tests

Basic Blood Studies

■anemia, thrombocytopenia, hemoglobinemia, reduced haptoglobin

levels, increased lactate dehydrogenase levels, increased unconju-

gated bilirubin levels, direct and indirect antiglobulin (Coombs’)

tests negative, increased BUN and creatinine

■DIC

■abnormal PT, PTT, and TT, decreased fibrinogen, increased fibrin

degradation products, increased D-dimers, decreased Factor V and

Factor VIII

■TTP

■normal PT, PTT, and TT, fibrinogen, coagulation factors

■HUS

■normal PT, PTT, and TT, fibrinogen, coagulation factors

Basic Studies: Peripheral Smear

■thrombocytopenia, schistocytes, microspherocytes, nucleated red

blood cells, reticulocytosis (polychromasia and macrocytosis),

leukocytosis

Basic Urine Studies

■hemoglobinuria, hemosiderinuria, increased urobilinogen, micro-

scopic hematuria, proteinuria, granular casts

Bone Marrow Biopsy

■erythroid hyperplasia

Tissue Biopsy

■eosinophilic, hyaline thrombi containing fibrin and/or platelet

aggregates occlude arterioles and small arteries

differential diagnosis

Infectious Agents

■gram-negative bacteria (e.g., Clostridium welchii) via secretion of

proteolytic enzymes

■parasites (e.g., Plasmodium sp., Babesia sp., Bartonella bacilliformis)

via direct parasitization of red blood cells