In connection with nephrectomy fatal liver and renal failure occurred after infusion of 50 g sorbitol in a 28 years old patient with undiagnosed fructose intolerance. A marked hypoglycemia and lactacidosis, an increase in uric acid, an acute liver failure with breakdown of excretory and synthetic function and disorder of hemostasis were typical of fructose/sorbitol infusion in hereditary fructose intolerance. Under adequate diet, as indicated in our case, HFI could be undiagnosed up to adult age. Therefore, fructose intolerance should be excluded by anamnesis before infusion of fructose/sorbitol. In unknown anamnesis (unconsciousness) fructose/sorbitol containing infusions should not be used. Fructose/sorbitol containing infusions should not be given routinely, but only with certain indication.