Non-Diabetic Kidney Disease in Patients with Type 2 Diabetes Mellitus–11-Year Experience from a Single Center

INTRODUCTION: In patients with diabetes mellitus (DM), non-diabetic renal disease (NDRD) can also occurs, as well as diabetic nephropathy. NDRD is most accurately diagnosed using kidney biopsy. AIM: The aim of the study was to investigate the incidence and type of NDRD diagnosed by kidney biopsy in patients with type 2 DM and the correlation of clinical and laboratory findings with histopathological diagnosis. MATERIAL AND METHODS: From April 2007 to October 2018, 290 kidney biopsies were performed at the Department of Nephrology, Internal Medicine Clinic in Banja Luka, out of which 18 patients (males 9, mean age 59.8 years) were with type 2 DM. The US-guided (ultrasound device: Toshiba Famio 5) kidney biopsy was performed using an automatic biopsy instrument FAST-GUN® with needle 16G. Kidney tissue samples were analyzed by light microscopy and immunofluorescence. RESULTS: In 18 patients with type 2 DM, the average duration of the disease was 5.9 years, 5 patients had a retinopathy, and 16 patients had hypertension. Biopsy indications were: nephrotic syndrome in 11 patients, asymptomatic urinary abnormalities in 3 patients, and rapid chronic renal failure progression. Unsatisfactory quality sample for pathohistological analysis was obtained in one patient, and out of the other 17, 6 (35.3%) had NDRD, 3 (17.6%) had NDRD superimposed with the diabetic nephropathy, and 8 (47.1%) had diabetic nephropathy. Of the patients who had NDRD, 3 had membranous glomerulonephritis, 1 had focal segmental glomerulosclerosis, and two had hypertensive nephroangiosclerosis. Out of patients with coexisting NDRD and diabetic nephropathy, 2 had hypertensive nephroangiosclerosis and one diabetic nephropathy and lupus nephritis. CONCLUSION: NDRD was diagnosed using kidney biopsy in 9/17 patients with type 2 DM, which confirms the significance of the kidney biopsy in patients with DM with properly indications. Accurate diagnosis provides disease specific treatment and thus significantly improves the long-term prognosis of the patient.