TUMOR-NECROSIS-FACTOR CONCENTRATIONS IN HEMOLYTIC-UREMIC SYNDROME PATIENTS AND CHILDREN WITH BLOODY DIARRHEA IN ARGENTINA

Hemolytic uremic syndrome (HUS) is thought to be a vascular endothelia l injury disease. The mechanism of injury is unknown although verocyto toxins (Shiga-like toxins (SLTs)) are known to be associated with it. Recent evidence suggests that in vitro treatment of some endothelial c ells with tumor necrosis factor alpha (TNF-alpha) dramatically increas es their susceptibility to SLTs, We studied 25 children with HUS, 63 c hildren with SLT-positive bloody diarrhea, 62 children with bloody dia rrhea not associated with SLTs and 39 children admitted for elective s urgery, included as an age- and season-matched control group. The TNF- alpha concentrations were found to be significantly elevated in childr en with HUS (range, 1 to 95 pg/ml; geometric mean, 32.2 pg/ml) compare d with the healthy controls (range, 0 to 53 pg/ml; mean, 12.5 pg/ml; P < 0.001), Because it is hypothesized that TNF-alpha elevation might p recede development of HUS, we also studied children with bloody diarrh ea. The TNF-alpha serum concentrations were significantly higher durin g the first 10 days after onset of bloody diarrhea than after the firs t 10 days (P < 0.02), Such elevation could be associated with vascular endothelial glycolipid receptor up-regulation and increased susceptib ility to the effects of SLTs.