Drug-induced hemolytic anemia

Triggers: anti-inflammatory medications, penicillins, and cephalosporins
Pathogenesis
- Drug coats erythrocytes → IgG binding → splenic destruction of RBCs (extravascular hemolysis)
- Drug triggers immune complexes → complement-mediated destruction of RBCs (intravascular hemolysis)
Manifestations
- Sudden onset (within hours of exposure)
- Anemia: fatigue, pallor, dyspnea
- Hemolysis: jaundice, dark urine, abdomen/back pain
  - ↑ Reticulocytes, indirect bilirubin & LDH
  - ↓ Haptoglobin
  - Spherocytes on peripheral blood smear
  - +Direct Coombs test (anti-IgG, anti-C3)
Treatment
- Discontinue offending drug