Renal histology in diabetic nephropathy: A novel perspective

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease all over the world. India has a high incidence and prevalence of diabetes and >30% have nephropathy. Recently, a histological classification has been proposed. This study analyzed the renal histology in 114 diabetic patients with renal dysfunction. Nearly 75% of patients had DN. Fifty five (63.95%) were males. Mean duration of diabetes was 7.04 ± 4.9 years. Mean serum creatinine in study group was 5.2 ± 2.9 mg/dl, with mean estimated glomerular filtration rate of 23.43 ± 21.48 ml/min/1.732 m(2). Forty eight patients (55.81%) had diabetic retinopathy (DR); prevalence of DR was more in patients who had diabetes for > 10 years than patients who had diabetes for <6 years (P = 0.022). The most common histological class was Class IV observed in 37 (43.02. %) cases, Class III DN in 24 (27.90%) cases, Class IIa and Class IIb in 11 (12.79%) cases each and Class I DN in 3 (3.48%) cases. Higher histological class was associated with higher proteinuria, lower glomerular filtration rate (P < 0.001) and was more likely to be associated with retinopathy (P = 0.012) and hypertension (P = 0.0003) but did not correlate with duration of diabetes (P = 0.85). There was a poor correlation between retinopathy and DN. Biopsy helps to stage the renal lesions in diabetics with renal dysfunction.