SUN-414 Renal biopsy in the elderly: indications, outcomes and prognostic factors A retrospective study about 70 patients

Abstract

Advances in health have led to longer life expectancy in all countries and as life expectancy increases, the number of elderly patients with kidney disease increases. The complexity of kidney damage in the elderly obscures the clinical picture. Without a renal biopsy, establishing a good diagnosis may be impossible, or at least prolonged. In this context fits our study that aims to clarify the main indications of renal biopsy and histological diagnostics in the elderly while specifying the risk factors for end-stage renal disease (ESRD). A retrospective observational study was conducted in elderly patients (≥65 years) who had received renal biopsies over 14 years (between January 2003 and December 2016). Demographic, clinical and pathological data at the time of the biopsy were collected from the medical records. Follow-up records and prognostic factors were studied. Outcomes of the renal biopsy were compared to a control group of patients aged between 40 and 64 years. The elderly accounted for 7.25% of native renal biopsies that were performed for 14 years. We included 70 patients in the study, 48 males (68.6%) and 22 females (31.4%). The most common indications for biopsy were an acute renal failure (72,8%) and nephrotic syndrome (24,3%). Common diagnosis included crescentic glomerulonephritis (27%), diabetic nephropathy (12,9%) and postinfectious acute glomerulonephritis (10%). In at least 48.5% of cases, renal biopsy showed histological lesions that can benefit from a therapeutic intervention. In the multivariate analyses, serum creatinine on admission was the only independent factor of poor renal outcome. Comparing histological outcomes with the control group, we found that crescentic glomerulonephritis was more common in the elderly with a significant difference and membranous nephropathy was more common in adults aged 40 to 64 years without significant difference with the elderly. The results of our study confirm the usefulness of renal biopsy in the elderly. Even in patients whose renal biopsy does not show lesions that can modify the therapeutic attitude, it can inform on the prognosis and /or avoid the prescription of the heavy treatments.