Treatment of Renal Failure-Reply

In Reply.—The BUN level is low in cirrhotic patients who have uncomplicated ascites. Azotemia in cirrhosis may thus reflect a greater magnitude of effective circulatory volume depletion than that found in normal individuals. The presence of spontaneous functional renal failure (FRF) (hepatorenal syndrome) has a particularly ominous connotation. Contrary to the statement of Drs Saghafi and Aghdasi, the diagnosis of hepatorenal syndrome is not difficult to make in patients with truly refractory ascites. Drs Saghafi and Aghdasi consider determination of urine osmolarity, urine to plasma osmolarity ratio, and urine to plasma creatinine ratio as essential measurements to determine the extent of renal damage in the FRF. These measurements are helpful in assessing the severity of renal disease but do not clearly distinguish FRF from acute tubular necrosis (ATN). In FRF, the renal tubules avidly reabsorb sodium from the glomerular filtrate displaying their excellent functional capacity. Urinary sodium concentrations, thus,