Kidney biopsy in the elderly.

Renal biopsy continues to play an essential role in the clinical assessment of hematuria, proteinuria and kidney failure. Nonetheless, the indications for renal biopsy are still controversial. The best determination of the potential benefit of an invasive diagnostic procedure comes from the demonstration that knowledge of a specific diagnosis guides the selection of treatments that produce improved outcomes. The size of the aging population is growing. In the years between 1980 and 1997, an 18% increase occurred in the number of individuals more than 65 years of age in the USA, and a 73% increase of those more than 85 years of age. Elderly patients are surviving longer with both acute and chronic disease, they are adapting to functional limitations in positive ways and they are choosing life-prolonging treatments that were not available to this population in the past. Despite these changes, several authors discuss physician biases that influence care of the elderly, and they argue that criteria for diagnosis and treatment should be the same as in younger patients. Many of the diagnoses made are treatable, and when treated, the outcome improves. Although comparison of survival data for patients with the general population would have been informative, data showing that loss of renal function correlates with shortened survival imply that interventions that delay progression to end-stage renal disease should significantly impact mortality. Thus, a bias toward limited diagnosis based on age alone is not justified. Histology is essential to precisely characterize the glomerular diseases underlying nonspecific clinical pictures and to direct the best therapeutic strategies. Our experience supported by larger studies from the United States showed that native kidney biopsy is safe and essential for diagnosis of renal disease and to direct the best therapeutic strategies in elderly patients.