Necrotizing enterocolitis with Escherichia coli heat-labile enterotoxin.

Twenty-one babies occupied a newborn intensive care unit during two separate clusters of necrotizing enterocolitis (NEC). Seven babies had suspected NEC, seven had proved NEC, two had diarrhea only, and five were unaffected. Of affected babies, 15 had toxigenic Escherichia coli or heat-labile E coli toxin in feces detected by enzyme-linked immunosorbent assay. One of five unaffected babies had fecal toxin (P = .01). Four of 12 affected babies had a fourfold immunoglobulin M (Igm) antitoxin titer rise within 3 weeks of the fecal studies. None of five unaffected infants had a serologic immune response. The clinical disease seen in the babies was not characteristic of previously described E coli heat-labile toxin-associated diarrhea.