Identification & characterization of Shiga toxin-producing Escherichia coli isolates from patients with diarrhoea in Iran

Indian J Med Res. 2010 Sep:132:328-31.

Abstract

Background & objectives: Verotoxigenic Escherichia coli are important serotypes of enterohaemorrhagic E. coli (EHEC) subgroup that cause attaching and effacing lesions in enterocytes by producing verotoxins or shiga-like toxins resulting in haemorrhagic colitis (HC) and haemolytic uremic syndrome (HUS). The aim of this study was to detect these serotypes specially E. coli O157:H7 in stool samples of patients with diarrhoea and identification of virulence genes (STX1, STX2, Hly and EAE) in Shahrekord-Iran area using PCR technique.

Methods: Two hundred diarrhoeal stool samples of patients were collected through 2007-2008. Microbiological and biochemical examinations were done to detect the E. coli. Serological tests carried out to identify the O157 or O157:H7 serotypes.

Results: Of the 58 E. coli isolates, 16 (27.6%) were detected as STX1 carrying E. coli, four (6.9%) carrying STX2, eight (13.8%) carrying both STX1 and STX2, and 12 (20.7%) were Hly carrying E. coli, but none of the isolates contained EAE gene. None of the isolates were E. coli O157 or O157:H7 serotypes.

Interpretation & conclusions: Our results revealed that verotoxigenic E. coli isolates other than O157 serotype were involved in causing diarrhoea in Shahrekord-Iran.

MeSH terms

  • Adhesins, Bacterial / genetics
  • Diarrhea / microbiology*
  • Escherichia coli O157 / genetics
  • Escherichia coli O157 / isolation & purification*
  • Escherichia coli O157 / metabolism*
  • Escherichia coli Proteins / genetics
  • Feces / microbiology*
  • Female
  • Hemolysin Proteins / genetics
  • Humans
  • Iran
  • Male
  • Shiga Toxin 1 / genetics
  • Shiga Toxin 2 / genetics
  • Shiga Toxins / metabolism*
  • Surveys and Questionnaires

Substances

  • Adhesins, Bacterial
  • Escherichia coli Proteins
  • Hemolysin Proteins
  • Hlya protein, E coli
  • Shiga Toxin 1
  • Shiga Toxin 2
  • Shiga Toxins
  • eaeA protein, E coli