Transurethral prostatectomy, with water as the irrigating fluid, is associated with prominent intravascular hemolysis, following which acute renal insufficiency develops in a proportion of cases.1This syndrome of acute renal insufficiency has been given various designations, such as the "renal anoxia syndrome,"2"lower nephron nephrosis"3and "hemoglobinuric nephrosis."4It has become apparent that the syndrome may result from a multiplicity of other causes, among which may be included prolonged hypotension (the shock state),5incompatible (hemolytic) blood transfusion reactions,6crush injuries, carbon tetrachloride poisoning,8uteroplacental damage9and certain infections.10The clinical picture and renal lesions are similar, regardless of the causative background. An outstanding feature of this syndrome has been the highrate of mortality. The methods of treatment for this condition have varied. The occasional spontaneous recovery in isolated cases has for some time demonstrated the reversible nature of the process involving