22-31: Sickle Cell Disease

Kidney disease associated with sickle cell disease is most commonly due to sickling of RBCs in the renal medulla because of low oxygen tension and hypertonicity. Congestion and stasis lead to hemorrhage, interstitial inflammation, and papillary infarcts with resultant necrosis. Clinically, hematuria is common, and proteinuria can be present as well, portending a poorer prognosis; both sickle cell trait and disease are associated with a faster decline in eGFR compared to those without the trait or disease. Damage to renal capillaries also leads to diminished concentrating ability. Isosthenuria (urine osmolality equal to that of serum) is routine, and patients can easily become dehydrated. Sickle cell glomerulopathy is less common but inexorably progresses to ESKD. Its primary clinical manifestation is proteinuria. Treatment centers on control of sickle cell disease and ensuring adequate fluid intake.