title: The prevalence and virulence characteristics of enteroaggregative Escherichia coli at an urgent-care clinic in the USA: a case-control study.
abstract: This case-control study examined the prevalence of enteroaggregative Escherichia coli (EAEC), its genes and elicited inflammatory response, and the stool characteristics of adult patients with and without acute diarrhoeal illness presenting to an urgent-care clinic in the USA. A total of 1004 individual stool specimens (253 from patients with acute diarrhoeal illness and 751 from patients without diarrhoeal illness) were collected between 1 June 2003 and 30 June 2008. EAEC was identified as the sole cause of acute diarrhoeal illness in 6 % (n=15) of patients and in 2 % (n=15) without diarrhoeal illness. Control patients (n=15) were similar to case patients (n=15) for age, gender and co-morbidities. The EAEC genes aggR, aap, aat, astA and/or set1A were identified more frequently in case patients compared with control patients (P <0.05). aggR-positive EAEC elicited higher levels of interleukin (IL)-1ra, IL-6, IL-8 and tumour necrosis factor-alpha compared with aggR-negative EAEC during co-incubation with HCT-8 cells. Patients with EAEC diarrhoea and isolates with the genes aggR, aap, aatA, astA or set1A had stools characterized by gross mucus and the presence of faecal leukocytes (P <0.05). These results indicate that EAEC is a potential cause of acute diarrhoeal illness affecting patients presenting to an acute-care clinic in the USA and suggest that aggR, aap, aatA, astA and set1A may be markers for virulence.
authors.affiliation: Veterans Affairs New Jersey Health Science Center, Department of Internal Medicine, Division of Infectious Diseases, 385 Tremont Avenue, East Orange, NJ 07018, USA.
authors.forename: David
authors.initials: D
authors.lastname: Cennimo
authors.affiliation: Veterans Affairs New Jersey Health Science Center, Department of Internal Medicine, Division of Infectious Diseases, 385 Tremont Avenue, East Orange, NJ 07018, USA.
authors.forename: Atif
authors.initials: A
authors.lastname: Abbas
authors.affiliation: Veterans Affairs New Jersey Health Science Center, Department of Internal Medicine, Division of Infectious Diseases, 385 Tremont Avenue, East Orange, NJ 07018, USA.
authors.forename: David B
authors.initials: DB
authors.lastname: Huang
authors.affiliation: Veterans Affairs New Jersey Health Science Center, Department of Internal Medicine, Division of Infectious Diseases, 385 Tremont Avenue, East Orange, NJ 07018, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Chiang
mesh_terms: D000328:Adult; D000554:Ambulatory Care Facilities; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology*; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology*; D005243:Feces / Q000382:microbiology; D006801:Humans; D015995:Prevalence; D014481:United States / Q000453:epidemiology; D014774:Virulence