[Changes in kidney function and morphology in the aged]

Increasing age of man leads to macroscopical and microscopical alterations in the kidneys. They cause a reduction of renal plasma flow, glomerular filtration rate and other renal functions. The characteristics of creatinine, blood urea nitrogen and uric acid in old people up to hundred years and over are discussed with regard to vitality and sex. The result of the reduction of kidney function is only a fully compensated renal insufficiency without need of specific therapy, but with need of dose reduction of drugs excreted with urine. The radiological renal cortical index (Vuorinen) is higher in old age because of the involution of renal cortical parenchyma. The sonographic B-scan is able to show these findings as well and to delimit them from pathological ones.