Nontoxigenic sorbitol-fermenting Escherichia coli O157:H- associated with a family outbreak of diarrhoea.

Abstract

A recent study from Germany reported the isolation of E. coli O157:H7/H- from patients with non-bloody diarrhoea and hemolytic uremic syndrome, questioning the role of Shiga toxin as the main trait of virulence for human disease. We isolated 6 sorbitol-fermenting E. coli O157:H- strains that do not contain Shiga toxin genes. The isolates originated from an outbreak (3 patients, 3 asymptomatic contacts) of non-bloody diarrhoea affecting two families sharing one household. Two children (age 10 months and 2 years) suffered severe diarrhoea over 30 and 10 days, respectively. Their uncle had moderate diarrhoea for 2 weeks. In contrast to the other isolates, the uncle's strain (EH109) did not harbour a chromosomal eae gene encoding gamma-intimin nor the plasmid gene E-hly; it also showed a PFGE pattern that was different from the unique pattern of the other isolates. Employing PFGE, phage typing, and P-gene typing, five of the six stx negative isolates were indistinguishable from the stx 2 positive "Bavarian outbreak strain". The only human serum tested, obtained from one asymptomatic contact, contained antibodies to the O157 lipopolysaccharide antigen. Our finding of five stx negative sorbitol-fermenting E. coli O157:H- isolates (harbouring eae and E-hly) associated with an outbreak of non-bloody diarrhoea supports the hypothesis that Stx production is not obligatory for the pathogenicity of E. coli O157 for humans.

• Authors: F Allerberger, M P Dierich, U Gruber-Moesenbacher, A Liesegang, R Prager, G Hartmann, W Rabsch, H Tschäpe, H Karch
• Journal: Wiener klinische Wochenschrift (Wien Klin Wochenschr) Vol. 112 Issue 19 Pg. 846-50 (Oct 13 2000) ISSN: 0043-5325 [Print] Austria
• PMID: 11098536 (Publication Type: Case Reports, Journal Article)

Chemical References

• Sorbitol
• Shiga Toxin

Topics

• Adult
• Austria (epidemiology)
• Bacteriophage Typing
• Child, Preschool
• Diarrhea (epidemiology, microbiology, physiopathology)
• Disease Outbreaks
• Electrophoresis, Gel, Pulsed-Field
• Escherichia coli Infections (microbiology)
• Escherichia coli O157 (enzymology, isolation & purification, metabolism)
• Humans
• Infant
• Middle Aged
• Severity of Illness Index
• Shiga Toxin (metabolism)
• Sorbitol (metabolism)