Spherocytosis

• • Malaise, abdominal discomfort

  • Jaundice, anemia, splenomegaly

  • Increased osmotic fragility of red cells, negative Coombs test

Epidemiology

• • The most common congenital hemolytic anemia, affecting 1:5000 persons

  • Transmitted as an autosomal dominant trait

  • Caused by deficiency of spectrin and ankyrin, erythrocyte membrane proteins, which maintain cellular osmotic stability and prevent splenic destruction

  • The normal shape of the erythrocyte is changed from a biconcave disk into a sphere, which causes a lack of deformability and delays passage through the channels of the splenic red pulp

  • Significant cell destruction occurs only in the presence of the spleen

  • Usually diagnosed in the first 3 decades; in occasional instances the diagnosis is not made until later in adult life

Symptoms and Signs

• • Mild to moderate anemia

  • Jaundice

  • Easy fatigability

  • Discomfort in the left upper quadrant

  • Splenomegaly

Laboratory Findings

• • Decreased hemoglobin

  • Negative Coombs test

  • Spherocytes on a Wright-stained smear

  • Increased reticulocyte count (5-20%)

  • Elevated indirect serum bilirubin and stool urobilinogen

  • Decreased or absent serum haptoglobin

  • Increased osmotic fragility, best demonstrated by the cryohemolysis test

• • Periodic exacerbations of hemolysis can occur

  • The rare hypoplastic crises, which often follow acute viral illnesses, may be associated with profound anemia, headache, nausea, abdominal pain, pancytopenia, and hypoactive marrow

  • Pigment gallstones occur in about 85% of adults with spherocytosis but are uncommon under age 10

  • -Gallstones in a child should suggest congenital spherocytosis

Rule Out

• • Spherocytes in large numbers may occur in autoimmune hemolytic anemias, in which osmotic fragility and autohemolysis may be increased

  • Spherocytes also occur in hemoglobin C disease, in some alcoholics, and in some severe burns

• • CBC

  • Wright stain peripheral smear

  • Coombs test

  • Tests of osmotic fragility: Cryohemolysis test

When to Admit

• • Hemolytic crisis

When to Refer

• • Should be managed in conjunction with a hematologist

Surgery

• • Splenectomy

  • When there is associated cholelithiasis, cholecystectomy should be performed along with the splenectomy

Indications

• • All patients older than 6 years, even if asymptomatic

Contraindications

• • Children younger than 6 years: High risk of infection; if high transfusion requirements, partial splenectomy

Treatment Monitoring

• • CBC

  • Haptoglobin level

  • Serum bilirubin

Complications

• • Pigment gallstones

  • Chronic leg ulcers

Prognosis

• • Splenectomy cures anemia and jaundice; the membrane abnormality, and increased osmotic fragility persist, but RBC life span is almost normal

References