RESUMO
In a study conducted in João Pessoa, northeast of Brazil, 2344 Escherichia coli isolated from 290 infants with diarrhea and 290 healthy matched controls were analyzed for virulence traits. Enteroaggregative E. coli (EAEC) was the most prevalent pathogen associated to acute diarrhea. Based on the results of colony blot hybridization, serotyping, and HEp-2 cell adherence assays, strains were separated in categories as typical enteropathogenic E. coli (EPEC) (1.7%), atypical EPEC (a-EPEC) (9.3%), EAEC (25%), enterotoxigenic E. coli (10%), and enteroinvasive E. coli (EIEC) (1.4%). No enterohemorrhagic E. coli strains were isolated. Other enteropathogens were found, including Salmonella (7.9%), Shigella spp. (4.1%), thermophilic Campylobacter spp. (2.4%), Giardia lamblia (9.3%), and Entamoeba histolytica (5.8%). All enteropathogens were associated with diarrhea (P < 0.01). However, the association was lower for EPEC and EIEC (P < 0.03). Different pathogens associated with diarrhea may have been changing in Brazil where EAEC and a-EPEC seem to be the most prevalent pathogens among them.
Assuntos
Diarreia Infantil/microbiologia , Escherichia coli Enteropatogênica/classificação , Infecções por Escherichia coli/microbiologia , Brasil/epidemiologia , Estudos de Casos e Controles , Adesão Celular , Linhagem Celular Tumoral , Distribuição de Qui-Quadrado , Diarreia Infantil/epidemiologia , Escherichia coli Enteropatogênica/genética , Escherichia coli/classificação , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Fezes/microbiologia , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Lactente , Prevalência , Sorotipagem , VirulênciaRESUMO
In this report, we analyzed the prevalence of the sat gene in 336 Escherichia coli samples collected from stools of children with and without diarrhea in Brazil and in 100 uropathogenic E. coli strains. The results show a high correlation between diffusely adhering E. coli (DAEC) and the presence of sat (44%) in intestinal isolates. DAEC strain FBC114 expresses a 107-kDa protein, which showed 98% homology with Sat.