Etiology:
Autosomal dominant mutation in RBC cytoskeleton proteins
Spectrin, ankyrin, band 3, protein 4.2
Common in Northern European descent
- Pathogenesis:
Defective RBC membrane → Loss of biconcave shape → Spherocytes
↓ RBC deformability → Trapped & destroyed in spleen → Extravascular hemolysis
↑ Osmotic fragility on acidified glycerol lysis test
- Clinical Features:
Hemolytic anemia, jaundice, splenomegaly
Gallstones (pigmented stones)
Aplastic crisis (parvovirus B19 infection)
- Treatment:
Splenectomy (definitive cure)
Folic acid supplementation