A 6-year-old boy has recurrent episodes of jaundice with dark urine. Examination shows mild splenomegaly. Peripheral smear shows spherocytes with no Auer rods or blasts. Direct antiglobulin test is negative. MCHC is increased on the automated counter.

• A Autoimmune hemolytic anemia
• B Hereditary spherocytosis ✓
• C G6PD deficiency
• D Paroxysmal nocturnal hemoglobinuria

Explanation

Hereditary spherocytosis is caused by defects in red cell membrane proteins, most commonly spectrin or ankyrin, producing spherical cells that are trapped and destroyed in the spleen. The raised MCHC reflects cellular dehydration from membrane loss. A negative Coombs test rules out autoimmune hemolysis, which is the main mimic on a spherocyte smear. G6PD deficiency shows bite cells and Heinz bodies during crises rather than persistent spherocytes, and PNH is confirmed by flow cytometry for GPI anchored proteins.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.