Abstract
In recent years, it has been revealed that verocytotoxin-producing E. coli (VTEC) infection is one of the leading causes of HUS and the molecular aspects of its pathophysiology have also been studied extensively. We report a case of a 56-year-old man who developed BUS after E. coli (0 26 strain) infection with diarrhea. The characteristic laboratory findings in this case included hypergammaglo bulinemia, hypocomplementemia and a high level of immune complex in addition to the common findings of HUS. The light microscopic findings of the first renal biopsy performed before treatment revealed extensive interstitial changes with remarkable mononuclear cell infiltrations as well as mild mesangial proliferation with crescent formation. Subendothelial electron-dense deposits within the glomerular capillary walls and mesangial area were also detected by electron microscopic examination. The diagnostic possibilities of infectious endocarditis and collagen diseases, such as Sjogren syndrome, were reasonably ruled out by the appropriate examinations. After 2-month prednisolone therapy, proteinuria and deteriorated renal functions as well as the abnormal immunological param eters described above were remarkably improved. The second renal biopsy after treatments showed clearly diminished subendothelial deposits and interstitial mononuclear cell infiltrations. This case report might provide information on the unique features of renal interstitial damage and immunolog ical abnormalities in VTEC-induced adult HUS.
