Spectrum of biopsy proven renal disease in the elderly – A retrospective observational study from South India

Background: Despite the increasing proportion of the elderly population, renal biopsies are restricted to few centers. We studied the elderly renal biopsy data from a tertiary care center in South India. Materials and Methods: A retrospective observational study was done in patients more than 60 years of age who underwent native kidney biopsy for various clinical indications from January 2014 to June 2022 and was compared with the renal pathology data of adults 18–60 years of age who underwent native kidney biopsy for various indications during the same study. Results: Hundred and five (n = 105) elderly biopsies were included in the study. The mean age was 65.7 years (interquartile range: 60–85 years). Forty-two (40%) were type 2 diabetics. Infection-related glomerulonephritis (IRGN) (20, 19.04%), acute tubular necrosis (ATN) (15, 14.28%), membranous nephropathy (11, 10.47%), and acute interstitial nephritis (10, 9.52%) were the common pathologies observed in the elderly. The most common indication for renal biopsy was rapidly progressive renal failure (RPRF) (n = 28, 26.6%) and IRGN was the most common cause of RPRF. 76.2% of diabetics had nondiabetic renal disease, the most common being IRGN (8, 25%). Crescentic glomerulonephritis (GN), ATN, and cast nephropathy were observed significantly more frequent in the elderly than in those 18–60 years of age. IRGN and pauci-immune vasculitis were the causes of crescentic GN in the elderly. Conclusion: Our study highlights the importance of IRGN as the most frequent pathology in the South Indian elderly population both in diabetics and nondiabetics.