Serum antibodies to verotoxin-producing Escherichia coli (VTEC) strains in patients with haemolytic uraemic syndrome.

Serological evidence of infection with verotoxin-producing Escherichia coli (VTEC) was sought in 28 patients suffering from haemolytic uraemic syndrome (HUS) and 25 age- and sex-matched controls. ELISA was used to detect anti-lipopolysaccharide (LPS) antibodies to E. coli strains O157, O111, O26 and NCTC 10418, a non-VTEC strain, and Shigella dysenteriae O1. Sera from 19 of the HUS patients but from none of the 25 controls had significant antibody levels to the verotoxin-producing bacteria. Sera from 13 patients reacted with only one LPS of the four verotoxin-producing bacteria; sera from six reacted with more than one LPS antigen but not with LPS of E. coli NCTC 10418. Paired sera taken 2-3 weeks apart were obtained from 20 HUS patients; 14 of these had high levels of antibody in the acute phase sample. Analysis of antibody levels in the convalescent sera showed that one patient had an increase, one was unchanged and 12 patients had a decrease in antibody to the verotoxin-producing bacteria.