[Nephrotic syndrome in the elderly. The most frequent causes of the nephrotic syndrome in the elderly (part I)].

Nephrotic syndrome (NS) is an essential clinical problem in the elderly. It may be difficult to recognize NS in the elderly because its symptoms are frequently missed with congestive heart failure or venous insufficiency. Glomerular diseases are not most common in elderly population but they play important role in renal pathology in this group of patients. Many structural and functional changes occur in the kidney with an increasing age. These changes may make, at least in part, the interpretation of renal lesions difficult. Glomerular pathology in this group of patients may be secondary to neoplastic diseases, and, therefore before the kidney biopsy screening for malignancies should be performed. The occurrence of particular forms of glomerular diseases differs between the older and young population. The most common forms of primary glomerular diseases in elderly are membranous nephropathy and focal-segmental glomerulosclerosis, whereas diabetic nephropathy and amyloidosis are common causes of secondary nephropathies. Kidney biopsy in the elderly gives valuable information, just as it is in the other age groups. It is a reasonably safe procedure, although associated with an increased risk of bleedings, when compared to younger population.