Enteroaggregative Escherichia coli virulence factors are found to be associated with infantile diarrhea in Brazil

• Autor(a) principal: Zamboni, Andresa [UNIFESP]
• Data de Publicação: 2004
• Outros Autores: Fabbricotti, Sandra H. [UNIFESP], Fagundes-Neto, Ulysses [UNIFESP], Scaletsky, Isabel CA [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://repositorio.unifesp.br/handle/11600/27641; http://dx.doi.org/10.1128/JCM.42.3.1058-1063.2004

We have previously shown that enteroaggregative Escherichia coli (EAEC) is an important pathogen among Brazilian infants. Most EAEC strains harbor a plasmid (pAA) from which a DNA fragment has been used as a probe (EAEC probe). To better understand the characteristics of EAEC in Brazil, 109 strains carrying and lacking the EAEC probe sequence were tested for the presence of pAA plasmid-borne and chromosomal factors. Common virulence factors of probe-positive and probe-negative isolates included the presence of the Pet, EAST-1, Shf, Irp2, ShET1/Pic, and Hly virulence markers. the presence of AggR or one other virulence factor (AAF/I, AAF/II, AAF/III, or Aap) was predominantly identified only in probe-positive strains. in EAEC probe-positive strains, the virulence marker Aap was found significantly more frequently (P = 0.023) in isolates from children with diarrhea (22%) than in isolates from controls (3%). EAST-I and Shf were the markers most frequently detected (61%) in EAEC probe-negative strains and were found to be significantly associated with diarrhea (P = 0.003 and P = 0.020, respectively). Furthermore, our data suggest that AggR can be used as an important genetic marker for EAEC probe-positive strains.