On four cases of hemolytic-uremic syndrome without microangiopathy

Four cases of hemolytic-uremic syndrome (HUS) are presented in which light and electron microscopic examination of renal biopsies (2 cases) and light microscopic examination of the kidneys on autopsy material (2 cases) revealed no changes reflecting microangiopathy. Based on these findings and on personal observation of 197 cases of HUS with glomerular or vascular changes, it is considered questionable whether the results of animal experiments by Brain et al. [1962] and Brian and Brain [1968] can be transferred to man. The cause of hemolytic anemia in HUS is considered unclarified, except for cases in which hemolysis is triggered by neuraminidase-producing bacteria and viruses.