Serum hippurate and its excretion in conservatively treated and dialysed patients with chronic renal failure

54 healthy volunteers or patients with normal kidney and liver function, 17 patients with decreased kidney function and 12 dialysed patients were evaluated for their serum hippurate accumulation and kidney excretion. It was found that there was an inverse relationship between serum hippurate and the clearance of endogenous creatinine (CCr) and a free relationship between fractional excretion of hippurate and CCr. The excretory capacity in residual nephrons was increased. This was caused by the greater glomerular filtration load which increased up to 25 times and tubular secretion which increased 7 times in dialysed patients. The relative contribution of glomerular filtration to hippurate excretion rose from about 20% in controls to almost 50% in dialysed patients. True kidney adaptation was localized in the organic anion transport system of proximal tubules.