Microangiopathic hemolytic anemia

Background

  • Abbreviation: MAHA
  • A variety of conditions that result in damaged endothelium of small vessels causing platelet aggregation and fibrin deposition which leads to shearing forces within these small vessels causing an intravascular fragmentation hemolysis

Clinical Features

  • Clinical features + heme labs with red blood cell fragments or schistocytes.[1]
  • May have bleeding and thrombosis
  • Signs and symptoms of anemia (fatigue, pallor, palpitations, etc.)
  • Jaundice and scleral icterus
  • Signs/symptoms of underlying disease process

Differential Diagnosis

Microangiopathic Hemolytic Anemia (MAHA)

Evaluation

  • Peripheral smear, hemoglobin, platelets, PT/INR, PTT, fibrinogen, FDPs, D-dimer, haptoglobin, LDH, bilirubin
    • Schistocytes (aka Helmet cells) secondary to fragmentation hemolysis classic finding on peripheral smear

Lab Findings

  • Schistocytes
  • High: +/- LDH and unconjugated bilirubin
  • Low: Hgb, platelets, +/- haptoglobin

General Rules

  • DIC= elevated PT/INR/PTT/FDPs/D-dimer, low fibrinogen[1]
  • TTP/HUS = normal PT/INR/PTT/FDPs/D-dimer/fibrinogen[1]

Management

Disposition

See Also

References

  1. 1.0 1.1 1.2 Scully. Marie et al. Guidelines on the diagnosis and management of thrombotic thrombocytopenic purpura and other thrombotic microangiopathies. Br J Haematol. 2012 Aug;158(3):323-35. PDF