CliniCon Oral Presentation Australian Society for Microbiology Annual Scientific Meeting 2024

‘Intimin-ating’ pathogens and their not so ‘eaeA-sy’ diagnosis (104592)

Jenny Wai Ying Yum 1 , Jenny Robson 1
  1. Sullivan Nicolaides Pathology, Brisbane, Queensland

The eaeA gene encodes the virulence factor intimin and serves as a marker for multiple pathotypes of Escherichia coli. This gene is frequently targeted in clinical laboratory diagnostic tests for enterohemorrhagic E. coli (EHEC), a well-recognised cause of severe and potentially life-threatening gastrointestinal (GI) disease. At Sullivan Nicolaides Pathology (SNP), EHEC PCR testing is performed upon special request and not for all routine stool specimens submitted for diarrhoea. Over the last 10 years, over 8% (n = 4255) of EHEC tests conducted at SNP have detected the presence of the eaeA gene in the absence of Shiga toxin virulence factor genes, the latter of which are principal genetic markers of EHEC. In these instances, a report is issued noting that infection with enteropathogenic E. coli (EPEC) may be present. A descriptive analysis of a subset of patients will be presented along with the presence of co-pathogens in order to determine the likely significance of this virulence factor in these patients. Additionally, addressing the limitations identified in the breadth of our current testing methodologies we highlight the launch of Microba’s MetaPanel - a metagenomic GI pathogen assay that can detect 175 targets including additional E. coli virulence factors of EPEC, EHEC serotype O157:H7, enteroaggregative E. coli, enterotoxigenic E. coli heat-labile toxins and heat-stable toxins, and enteroinvasive E. coli invasion plasmid. We hope the delivery of this assay will provide a better understanding of the role of the various pathogenic E. coli’s in not only infectious diarrhoea but their role in exacerbation of inflammatory bowel disease.