Nondiabetic Renal Disease in type 2 Diabetes Mellitus Patients: A Clinicopathological Study

BACKGROUND: The prevalence of nondiabetic renal disease (NDRD) among type 2 diabetics varies widely depending on the populations being studied and the selection criteria. Also, for patients found to have NDRD different predicting factors have been identified by different studies. OBJECTIVES: To determine: (i) Frequency and spectrum of NDRD in type 2 diabetics with atypical clinical renal disease, in our set up and (ii) common clinical markers that are associated with NDRD in our local population. MATERIALS AND METHODS: Ninety-three type 2 diabetic patients with atypical clinical renal disease who had undergone renal biopsy to rule out NDRD were recruited. Patients were grouped into Group 1 with isolated NDRD, Group 2 with NDRD superimposed on diabetic nephropathy (DN), and Group 3 with isolated DN; and their clinical and biochemical parameters were statistically analyzed using analysis of variance, Kruskal-Wallis test, and Chi-square tests of statistical significance. RESULTS: 68.8% of the patients had NDRD with or without concurrent DN. Patients with isolated NDRD had shorter duration of diabetes compared to the other groups. Absence of retinopathy and presence of microscopic hematuria and active urinary sediment had positive predictive value of 79.24, 81, and 100%, respectively, for NDRD in type 2 diabetics. Chronic interstitial nephritis was the commonest NDRD and membranous glomerulonephritis was the commonest glomerular NDRD in our setup. INTERPRETATION AND CONCLUSIONS: The frequency of NDRD in type 2 diabetics with atypical clinical renal disease is high in our setup thereby making the renal biopsy procedure imperative to rule out the same. Shorter duration of diabetes, absence of retinopathy, presence of microscopic hematuria, and active urinary sediment are markers associated with NDRD in type 2 diabetes with clinical renal disease.