Shiga Toxin-Producing Escherichia coli Infections in Germanyt

A prospective study was carried out in collaboration with two children's hospitals in Wiirzburg, Germany to assess the incidence and clinical manifestations of infections due to Shiga toxinproducing Escherichia coli (STEC) in children. Between 1991 and 1995, stool samples from 2788 children with enteritis were investigated for the occurrence of STEC. STEC cultures from stools were screened using PCR with primers complementary to Shiga toxin I (Stxl) and Shiga toxin 2 (Stx2) genes. PCR-positive samples were further subjected to colony blot hybridization and probe positive colonies were serotyped and analyzed for the presence of virulence genes. There was an increase in the incidence ofSTEC infections from 0.4% in 1991 to 2.8% in 1994. In 1995 the number of infections remained nearly unchanged (2.5%). Infection with STEC was associated with painful nonbloody diarrhea in most patients. Among the 35 patients in this study with stools containing STEC, only 9 (25.7%) had 0157 colonies of which 3 (8.6%) were 0157:H7 and 6 (17.1%) were sorbitol-fermenting 0157:H-. In an additional study in 1994/l995, STEC etiology in 88 patients with HUS from Germany was confirmed in our laboratories by culture of STEC from stools, and in 20 additional HUS cases by serological analysis. Of the strains from stools of HUS patients, 78% belonged to serogroup 0157. The most frequently isolated non-0157 serogroups were 026 and Olll. These results demonstrate that when analyzing stools of patients with bloody diarrhea, HUS, or painful nonbloody diarrhea, the occurrence of non0157:H7 strains should be considered when classical microbiological analysis fails to yield a standard enteric pathogen, such as Campylobacter, E. coli 0157:H7, Salmonella, Shigella, or Yersinia.