An appraisal of kidney dysfunction and its risk factors in patients with sickle cell disease.

Sickle cell disease (SCD), a genetically inherited disease of blacks, often presents with disabling acute complications which can occasionally be fatal. Its renal manifestations are increasingly being recognized as affected patients now survive to middle and rarely old age. We set out to determine the magnitude of kidney dysfunction in our SCD patient population and evaluate its predictive factors. We reviewed the available case records of SCD patients managed in our hospital. Information on socio-demographic, clinical and laboratory data were retrieved and collated. A total of 374 (99.46%) were reviewed with complete data; the median age was 23 years (range 7-62), while median age at diagnosis of SCD was 4 years (range 0.25-31). 235 patients (68.2%) had no kidney disease while the remaining 139 (37.2%) had proteinuria, hematuria or reduced glomerular filtration rate (GFR) <60 ml/min. The age of patients was a significant predictor of kidney disease (p = 0.002) and correlated with the level of serum creatinine (r = 0.188, p < 0.001), GFR (r = 0.245, p < 0.0001) and the degree of proteinuria (r = 0.174, p = 0.006). Patients with kidney disease had a significantly higher number of crises/hospitalizations (p < 0.001). Seven patients died in all and 4 (57%) of them had end-stage renal disease. We concluded that kidney disease is a common complication of SCD and significantly contributes to mortality. The age of the patients, duration of SCD and frequency of crises/hospitalizations are strong predictors of development of kidney disease.