Renal biopsy in patients over 75: 131 cases

Introduction: Demographic analysis shows the ageing of the global population and the consequent increase in the age of hospitalized subjects and of patients starting dialysis. Hence, interest in the feasibility, safety, and usefulness of renal biopsy in elderly patients is growing. We examined the data of 131 patients over the age of 75 who underwent renal biopsy. We analyzed the safety of the procedure, treatment, and outcomes. Results: Histological diagnoses included: membranous glomerulonephritis (GN) 20.6%, crescentic GN 12.9%, IgAGN 10.6%, focal segmental glomerulosclerosis 9.1%, acute GN 4.5%, amyloidosis 9.1%, and acute tubular necrosis 3.8%. Mean glomerular obsolescence was 28.9 ± 27.9%. Mean age of the patients was 78.7 ± 5.73 years. At the time of biopsy, serum creatinine (SCr) was 4.47 ± 2.56 mg/dL and proteinuria was 4.82 ± 6.78 g/day. Targeted treatment was given to 51.9% of patients, 52.9% of whom had a good clinical response. Eight patients had clinically non-relevant side effects (11.7%). A positive response (defined as a more than 50% reduction of SCr, or by partial or complete remission of proteinuria) was observed in 36 patients (52.9%). 76 patients were monitored for 57 ± 9.89 months: 18 patients were on dialysis (follow-up 2.56 ± 3.61 months), 15 died (follow-up 58.5 ± 13.43 months), and 52 remained under nephrologic observation for 36 ± 31 months (SCr was 2.56 ± 0.75 mg/dL and proteinuria was 4.82 ± 6.78 g/day). Conclusion: In our experience, renal biopsy is safe even in very elderly patients; it allowed targeted treatment in 51.9% of patients, 52.9% of whom had a good clinical response, possibly contributing to prolonged patient survival and improved quality of life.