In hereditary spherocytosis due to ankyrin deficiency, spherocytes form because the lipid bilayer is destabilised from the inner cytoskeletal network. The spherocytes are then sequestered and destroyed in a specific anatomical compartment of the spleen. Which compartment is responsible?

• A Perifollicular white pulp marginal zone
• B Periarterial lymphoid sheath (PALS)
• C Splenic sinusoids (red pulp) ✓
• D Trabecular veins at the hilum

Explanation

Spherocytes, lacking normal deformability due to reduced surface area-to-volume ratio, cannot squeeze through the narrow slits between splenic sinus endothelial cells in the red pulp cords. They are detained in the red pulp cords, where repeated trafficking and metabolic stress (acidic pH, glucose deprivation) lead to their phagocytosis by resident macrophages. This explains why splenectomy dramatically improves the anaemia in hereditary spherocytosis despite the intrinsic red cell defect persisting.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.