Urine Albumin/creatinine ratio: A reliable marker of renal injury in sickle cell nephropathy

Abstract

Objective: Albumin/creatinine ratio is a sensitive marker of glomerular damage in patients with diabetes mellitus, hypertension and post-infection glomerulonephritis. Whether or not the albumin/creatinine ratio has the same value in sickle cell anemia (SCA) patients is not yet explored. This study was conducted to determine the prevalence of glomerular damage in SCA and the clinical correlation between albumin/creatinine ratio and renal insufficiency in this group of patients. Materials and Methods: Seventy-nine adult patients with SCA (hemoglobin SS subtype) were included in this study. Albumin excretion rates (expressed as albumin/creatinine ratio) and renal function (creatinine clearance) were determined and clinical and hematologic evaluations were conducted. Results: Increased albumin/creatinine ratio (micro- and macroalbuminuria) occurred in 57% of the patients. The development of graded albuminuria was time dependent; therefore, at the end of the study, 26.6% of the patients had macroalbuminuria. There were no differences in hemoglobin levels between patients with normoalbuminuria and those with micro- or macroalbuminuria. By multivariate analysis, albuminuria correlated with age and creatinine clearance (Cr Cl) but not with blood pressure (BP) or hemoglobin levels. Conclusion: Albumin/creatinine ratio is a sensitive marker of glomerular damage in SCA patients, and it correlated well with Cr Cl; therefore, patients with abnormal albumin/creatinine ratio should be monitored closely for progression of renal disease. The development of micro- and macroalbuminuria is related to age but not to the degree of anemia, suggesting that sickle cell glomerulopathy is not solely related to hemodynamic adaptations to chronic anemia.

Keywords

• Albumin/creatinine ratio
• Cr Cl
• ESRD
• hemoglobin
• renal insufficiency
• SCA