Clinical and laboratory findings of patients with diabetes undergoing kidney biopsy

Diabetic kidney disease (DKD), one of the most frequent microvascular complications of diabetes mellitus (DM), is the leading cause of end-stage kidney disease worldwide. We reviewed all kidney biopsies performed at the Royal Hospital, Muscat, Oman, between January 2005 and December 2016, and data of 51 DM patients were analyzed. Of the 51 patients, 54.9% were male and 45.1% were female. The mean age was 50.8 (47.1-55.2) years; 86% were between 25 and 64 years old. Edema was the main clinical presentation (70.6%) with clinical urine changes in 84.3%. Diabetic retinopathy was present in 62.2% in ophthalmological examination of 44 patients. Majority (67.5%) of patients were in advanced chronic kidney disease Stages III, IV, and V. About one-quarter underwent hemodialysis at the time of admission. Majority (76.9%) were obese and hypertensive (78.4%). Low hemoglobin (51%), high triglyceride (35.7%), high total cholesterol (56.8%), low serum albumin (78.4%), nephrotic-range proteinuria (75.6%), and microscopic hematuria (77.1%) were the main laboratory findings. In addition, immunological investigations were examined and immunoglobulin A was the most common findings (35.7%) of serological investigations. About 24.4% had positive antinuclear antibody, 20.8% had positive anti-dsDNA, and 23.3% had positive extractable nuclear antigens. Also, p-antineutrophil cytoplasmic antibody (p-ANCA) was positive in 30% and c-ANCA was positive in 9.7%. This study represents the findings of the whole country for more than 10 years. It showed that only a small percentage of patients with DM undergo kidney biopsy. These patients have many clinical and laboratory abnormalities including those of specific immuno-logical investigations. Progression of DM nephropathy seems to be further aggravated by many coexisting risk factors of dyslipidemia and/or obesity. The prevalence of non-DKD is remarkably frequent in diabetics in whom nephrologists should consider kidney biopsy as an appropriate measure to enable better management.