title: Characterization of enteroaggregative Escherichia coli strains isolated from children with acute diarrhea, in Mendoza, Argentina.
abstract: Enteroaggregative Escherichia coli (EAEC) is an increasingly recognized cause of diarrhea in children in developing and developed countries. EAEC is recognized by a characteristic aggregative pattern of adherence to human epithelial (HEp-2) cells cultured in vitro. This is the gold standard assay. The aggregative phenotype is associated with the presence of a 65 MDa plasmid (pAA) that also encodes several other putative virulence factors, such as the aggregative adherence fimbria I (AAF/I) and the enteroaggregative heat-stable enterotoxin (EAST1). The objective of this work was to evaluate the application of PCR (polymerase chain reaction) to identify EAEC strains in cases of acute diarrhea. A total of 87 E. coli strains, isolated from patients under 2 years of age with acute diarrhea in Mendoza, Argentina, were characterized by the reference method (HEp-2 assay), and by AAF/I- and EAST1-PCR. PCR sensitivity and specificity in comparison with the cell culture assay showed 94.4% sensitivity and 78.26% specificity. EAST1- and AAF/I-PCR could be recommended as a screening test, applicable to epidemiologic studies.
authors.affiliation: Areas de Química Biológica y Microbiología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina. mruttler@fmed2.uncu.edu.ar
authors.forename: M E
authors.initials: ME
authors.lastname: Rüttler
authors.forename: N F
authors.initials: NF
authors.lastname: Renna
authors.forename: L
authors.initials: L
authors.lastname: Balbi
authors.forename: B
authors.initials: B
authors.lastname: García
authors.forename: L
authors.initials: L
authors.lastname: Guidone
authors.forename: R
authors.initials: R
authors.lastname: Fernández
authors.forename: O
authors.initials: O
authors.lastname: Puig
authors.forename: A
authors.initials: A
authors.lastname: Ortiz
mesh_terms: D001118:Argentina / Q000453:epidemiology; D001422:Bacterial Adhesion; D001427:Bacterial Toxins / Q000235:genetics; D003968:Diarrhea, Infantile / Q000382:microbiology*; D004768:Enterotoxins / Q000235:genetics; D004847:Epithelial Cells / Q000382:microbiology; D004926:Escherichia coli / Q000302:isolation & purification* / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000382:microbiology*; D036781:Fimbriae Proteins / Q000235:genetics; D010861:Fimbriae, Bacterial / Q000235:genetics; D006801:Humans; D007223:Infant; D008403:Mass Screening; D010641:Phenotype; D010957:Plasmids; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D014407:Tumor Cells, Cultured / Q000382:microbiology; D014774:Virulence
chemical_list: D001427:Bacterial Toxins; D004768:Enterotoxins; D036781:Fimbriae Proteins