title: Association of diarrheagenic Escherichia coli Pathotypes with infection and diarrhea among Mexican children and association of atypical Enteropathogenic E. coli with acute diarrhea.
abstract: Seventy-six children < or =2 years old were prospectively followed for 1 year in a peri-urban community of Mexico City to determine asymptomatic infection and acute diarrhea associated with diarrheagenic Escherichia coli pathotypes (DEPs). By use of a pathogen-specific multiplex PCR, DEPs were sought in 795 stool samples, of which 125 (16%) were positive for DEP; of these, 4 represented shedding episodes and 4 parasite coinfections. Most single-DEP infections (85/117) were asymptomatic (P < 0.001), and of the 32 DEP diarrhea episodes, 41% were associated with atypical enteropathogenic E. coli (aEPEC), 37.5% with enterotoxigenic E. coli, 9% with typical EPEC, 9% with enteroinvasive E. coli, and 3% with Shiga toxin-producing E. coli strains. Among the 76 children, 54 had at least one stool positive for DEP, of which 23 experienced a DEP-associated diarrhea episode. In the last group of children, DEP infection was significantly associated with a diarrhea episode (relative risk [RR] = 2.5; 95% confidence interval [CI], 1.79 to 3.57; P < 0.001), with ETEC (RR = 2.30; 95% CI, 1.49 to 3.54; P = 0.003) and aEPEC (RR = 1.92; 95% CI, 1.23 to 3.0; P = 0.019) being the pathotypes associated with diarrhea. aEPEC-associated diarrhea episodes were frequently in the <12-month age group (RR = 2.57; 95% CI, 1.05 to 6.27; P = 0.04). aEPEC infections were distributed all year round, but associated diarrheal episodes were identified from April to October, with a May-June peak (rainy season). Most ETEC infections and diarrhea episodes characteristically occurred during the summer (rainy season), with a diarrhea peak in August. Of all DEPs, only aEPEC was associated with acute diarrhea episodes lasting 7 to 12 days (P = 0.019). DEPs are important causes of community-acquired enteric infection and diarrhea in Mexican children.
authors.affiliation: Department of Molecular Biomedicine, CINVESTAV-IPN, Av. IPN No. 2508, Col. Zacatenco, C.P. 07360, Mexico City, Mexico. testrada@cinvestav.mx
authors.forename: Teresa
authors.initials: T
authors.lastname: Estrada-Garcia
authors.forename: Catalina
authors.initials: C
authors.lastname: Lopez-Saucedo
authors.forename: Rocio
authors.initials: R
authors.lastname: Thompson-Bonilla
authors.forename: Maricela
authors.initials: M
authors.lastname: Abonce
authors.forename: Daniel
authors.initials: D
authors.lastname: Lopez-Hernandez
authors.forename: Jose Ignacio
authors.initials: JI
authors.lastname: Santos
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Rosado
authors.forename: Herbert L
authors.initials: HL
authors.lastname: DuPont
authors.forename: Kurt Z
authors.initials: KZ
authors.lastname: Long
mesh_terms: D000367:Age Factors; D004269:DNA, Bacterial / Q000235:genetics; D003967:Diarrhea / Q000453:epidemiology* / Q000382:microbiology*; D054308:Enteropathogenic Escherichia coli / Q000145:classification / Q000302:isolation & purification*; D054307:Enterotoxigenic Escherichia coli / Q000145:classification / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology*; D029968:Escherichia coli Proteins / Q000235:genetics; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008800:Mexico / Q000453:epidemiology; D016133:Polymerase Chain Reaction / Q000379:methods; D011446:Prospective Studies; D012621:Seasons; D037521:Virulence Factors / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D037521:Virulence Factors