title: Adherence and virulence genes of Escherichia coli from children diarrhoea in the Brazilian Amazon.
abstract: The bacterial pathogen most commonly associated with endemic forms of childhood diarrhoea is Escherichia coli . Studies of epidemiological characteristics of HEp-2 cell-adherent E. coli in diarrhoeal disease are required, particularly in developing countries. The aim of this study was evaluate the presence and significance of adherent Escherichia coli from diarrhoeal disease in children. The prevalence of LA, AA, and DA adherence patterns were determined in HEp-2 cells, the presence of virulence genes and the presence of the O serogroups in samples obtained from 470 children with acute diarrhoea and 407 controls in Porto Velho, Rondônia, Brazil. E. coli isolates were identified by PCR specific for groups of adherent E. coli . Out of 1,156 isolates obtained, 128 (11.0%) were positive for eae genes corresponding to EPEC, however only 38 (29.6%) of these amplified bfpA gene . EAEC were isolated from 164 (14.1%) samples; of those 41(25%), 32 (19%) and 16 (9.7%) amplified eagg , aggA or aafA genes, respectively and aggA was significantly associated with diarrhoea ( P = 0.00006). DAEC identified by their adhesion pattern and there were few isolates. In conclusion, EAEC was the main cause of diarrhoea in children, especially when the aggA gene was present, followed by EPEC and with a negligible presence of DAEC.
authors.affiliation: Instituto de Pesquisas em Patologias Tropicais, Fundação Oswaldo Cruz, Porto Velho, RO, Brazil.
authors.forename: Najla
authors.initials: N
authors.lastname: Benevides-Matos
authors.affiliation: Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz, Manaus, AM, Brazil.
authors.forename: Fabio A
authors.initials: FA
authors.lastname: Pieri
authors.affiliation: Hospital Infantil Cosme e Damião, Secretaria de Estado da Saúde, Porto Velho, RO, Brazil.
authors.forename: Marilene
authors.initials: M
authors.lastname: Penatti
authors.affiliation: Instituto Leônidas e Maria Deane, Fundação Oswaldo Cruz, Manaus, AM, Brazil.
authors.forename: Patrícia P
authors.initials: PP
authors.lastname: Orlandi
mesh_terms: D001422:Bacterial Adhesion; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D003967:Diarrhea / Q000382:microbiology*; D054308:Enteropathogenic Escherichia coli / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D004847:Epithelial Cells / Q000382:microbiology; D004926:Escherichia coli / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D004927:Escherichia coli Infections / Q000382:microbiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D019081:O Antigens / Q000032:analysis; D065288:Serogroup; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D019081:O Antigens; D037521:Virulence Factors
keywords: Enteroadherent Escherichia coli; children; diarrhoea