Background: Renal abnormalities discovered in the elderly have often been considered the result of aging, hypertensive changes, and so on. Recently, we noted an increase in renal biopsies among patients 80 years and older. This is a demographic subset with little or no previously reported clinicopathologic correlation between renal biopsy findings and clinical syndromes.
Methods: We examined our files for all biopsies performed in patients 80 years and older and report 100 patients of a total of 3,227 biopsies (3.1%) from multiple referral centers.
Results: Significant differences in the disease spectrum were found in the very elderly, not only compared with studies of adults and children, but also compared with studies of renal biopsies in the elderly. Crescentic glomerulonephritis was the most common diagnosis in patients aged 80 years and older. Although membranous glomerulopathy is the most common cause of idiopathic nephrotic syndrome in studies of the elderly (23% to 38%) and adults (35% to 40%), only 15% of our patients aged 80 years and older with idiopathic nephrotic syndrome had membranous nephropathy. Overall, at least 40 of 100 biopsies performed on the very elderly showed a renal condition that would benefit from therapeutic intervention, and the remaining biopsies provided at least prognostic information and/or ruled out a more severe condition, preventing potentially harmful empiric therapy.
Conclusion: As the population ages, more elderly patients are undergoing diagnostic renal biopsies. This study emphasizes the variance between clinical presentation and expected diagnosis compared with actual biopsy findings in patients aged 80 years and older.