[Primary tubular impairment by verocytotoxin in hemolytic uremic syndrome]

Hemolytic uremic syndrome (HUS) in childhood is recognized as the most frequent cause of acute renal failure and is greatly associated with verotoxin-producing E. coli (VTEC) infection. Most of the prodromal feature in HUS associated with VTEC infection is hemorrhagic colitis (HC). HC progresses to HUS in several days. So it is important to detect whether the patient with bloody diarrhea is associated with VTEC infection or not. From 1992 to 1996 we analyzed clinical findings of 80 HUS and 29 HC patients. High level of beta 2-microglobulin (BMG) and N-acetyl-D-beta-glucosaminidase (NAG) in the urine were observed in the early stage of the disease. We went on to examine verotoxin (VT2)-binding in mouse (ICR) renal sections by enzyme immunoassay. Specific binding of VT2 to tubules was seen in mouse kidney, and intravenous injection of VT2 to mice caused acute tubular necrosis in 15 h whereas glomeruli were intact. These data suggest that the primary target cell of VT2 was tubules in the kidney of the HUS patients with VTEC infection.