Pham TT et al. (2007) Prevalence of nondiabetic renal disease in diabetic patients. Am J Nephrol 27: 322–328

A retrospective analysis from the US has reported a high prevalence of nondiabetic renal disease (NDRD) among diabetic patients undergoing renal biopsy.

Although patients with type 2 diabetes mellitus often experience diabetic nephropathy, they can also develop other renal diseases pathologically unrelated to diabetes. Nephrologists are, however, often reluctant to perform a renal biopsy—which would confirm the etiology of renal disease—in diabetic patients showing signs of nephropathy.

To determine the prevalence of NDRD in patients with type 2 diabetes, with or without evidence of diabetic glomerulosclerosis, Pham and co-workers reviewed the biopsy reports of 233 adults (mean age 58.1 ± 13.7 years) who underwent renal biopsy at a single center during the period 1995–2005.

The researchers found that 53.2%, 27.5%, and 19.3% of the patients had been diagnosed with NDRD, pure diabetic glomerulosclerosis, or concurrent NDRD and diabetic glomerulosclerosis, respectively. In patients with NDRD, the most common lesion was focal segmental glomerulosclerosis, seen in 21.0% of NDRD cases, followed by minimal-change disease (in 15.3%). In patients with concurrent NDRD and diabetic glomerulosclerosis, the most common lesions were IgA nephropathy, membranous glomerulonephritis and arterial/arteriolar nephrosclerosis, seen in 15.6%, 13.3% and 13.3% of cases, respectively. Absence of diabetic retinopathy was predictive of NDRD.

In light of the high prevalence of NDRD found in this study, the authors recommend that nephrologists maintain a low threshold of clinical suspicion for performing renal biopsy in diabetic patients. Early diagnosis of NDRD is crucial, as appropriate therapy could prolong renal survival in this patient population.