Rapidly Progressive Renal Failure in Type 2 Diabetic versus Non-diabetic Patients: Changing Trends, Natural History, and Outcome in an Indian Tertiary Care Center.

Rapidly progressive renal failure (RPRF) is not typical of diabetic nephropathy and suggests non-diabetic kidney disease (NDKD). We conducted an analysis of the data of RPRF patients (28 diabetic and 88 non-diabetic patients) with doubled creatinine over 2 weeks to 3 months and/or presented with >4 mg serum creatinine without prior renal disease to ascertain the types of lesions and compare the patients' histopathology. The primary outcome was dependence on dialysis at 1 year. Anti-neutrophilic cytoplasmic antibody-associated pauci-immune glomerulonephritis was the most common cause of RPRF in both groups. No particular lesion was more frequent in either group. Dependence on dialysis at 1 year was similar in both groups and was associated with dependence on dialysis at presentation but not diabetes. Crescentic glomerulonephritis was the most common in non-diabetic patients (57.9 vs. 25%, P = 0.002), and acute tubular necrosis (ATN) was seen in diabetic patients (21.4 vs. 11.4%, P = 0.179). Both factors were associated with adverse renal outcomes. Diffuse global glomerulosclerosis at presentation suggested a poor outcome in both groups. Diabetic nephropathy was seen in 14.29%, and its presence did not affect the outcome. The etiology of RPRF in diabetic patients has changed and is similar to that in non-diabetic patients, with no specific lesions predominating. Diabetic nephropathy does not alter the outcome for those with RPRF. Diffuse global glomerulosclerosis, being on dialysis at presentation, and ATN in a diabetic patient indicate a poor outcome and need close follow-up. Diabetic retinopathy should not prevent us from investigating for NDKD.