Virulence profile comparison between LEE-negative Shiga toxin-producing Escherichia coli (STEC) strains isolated from cattle and humans

For comparison purposes, the prevalence of 8 virulence markers was investigated, by PCR, in 153 cattle and 47 human Locus for Enterocyte Effacement (LEE)-negative Shiga toxin-producing Escherichia coli (STEC) strains isolated in Argentina. Also, their correlation with severe disease was established. The virulence markers studied comprises 5 fimbrial and nonfimbrial adhesin-encoding genes (fimA, iha, efa1, lpfAO113, and saa) and 3 toxin genes (cdt-V, subAB and astA) in addition to the Shiga toxins. The most prevalent virulence marker found was that encoded by the lpfAO113 gene (199/200, 99%). Comparatively, the lpfAO113, fimA, iha, saa, subAB, cdt-V and astA genes were detected in 100%, 92.8%, 85%, 52.9%, 36%, 11.8% and 9.8% of the cattle strains and in 97.9%, 95.7%, 89.4%, 40.4%, 32%, 17% and 10.6% of the human strains, respectively. All STEC strains were efa1 negative. The most prevalent profile observed among cattle and human STEC strains was lpfAO113 iha fimA. These results show that bovine LEE-negative STEC strains possessed genes encoding virulence factors present in human LEE-negative STEC strains that are associated with disease. Despite a great diversity of virulence profiles observed, further studies comparing wild type strains and their allelic mutants are needed to evaluate the role of each factor in the pathogenesis of LEE-negative STEC strains during human infections.Fil: Galli, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Miliwebsky, Elizabeth. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Irino, Kinue. Instituto Adolfo Lutz; BrasilFil: Leotta, Gerardo Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Rivas, Marta. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentin

Inability to decarboxylate lysine as a presumptive marker to identify shiga toxin-producing Escherichia coli strains of serogroup 0111

Universidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, BrazilInst Adolfo Lutz Registro, Secao Bacteriol, BR-01246902 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, BR-04023062 São Paulo, BrazilWeb of Scienc

Phenotypic characteristics, virulence profile and genetic relatedness of O157 Shiga toxin-producing Escherichia coli isolated in Brazil and other Latin American countries

Thirty-eight Shiga toxin-producing Escherichia coli (STEC) O157:H7/H- strains isolated from human infections, cattle and foods in Brazil and in some other Latin American countries were compared with regard to several phenotypic and genotypic characteristics. the genetic relatedness of the strains was also determined by pulsed-field gel electrophoresis (PFGE). Similar biochemical behaviour was identified, regardless of the origin and country of the strains. Most (89.5%) strains were sensitive to the antimicrobial agents tested, but resistance to at least one drug was observed among bovine strains. Although a diversity of stx genotypes was identified, most (77.8%) of the human strains harboured stx(2) or stx(2)stx(2c(2vha)), whereas stx(2c(2vha)) prevailed (64.2%) among strains isolated from cattle. stx(1) and stx(1)stx(2c(2vha)) were the genotypes identified less frequently, and occurred exclusively among strains isolated from food and cattle, respectively. Despite differences in the stx genotypes, all strains carried eae-gamma, efa1, ehx, iha, lpf(O157) and toxB sequences. Many closely related subgroups (more than 80% of similarity) were identified by PFGE, and the presence of a particular O157:H7 STEC clone more related to human infections in Brazil, as well as a common origin for some strains isolated from different sources and countries in Latin America can be suggested.Universidade Federal de São Paulo, Disciplina Microbiol, Escola Paulista Med, BR-04023062 São Paulo, BrazilInst Adolfo Lutz Registro, São Paulo, BrazilUniversidade Federal de São Paulo, Disciplina Microbiol, Escola Paulista Med, BR-04023062 São Paulo, BrazilWeb of Scienc

Biotipagem, sorotipagem e ribotipagem na avaliação epidemiológica de A. baumannii em unidades hospitalares, Sorocaba, São Paulo, Brasil

Dissemination of Acinetobacter baumannii strains in different units of a hospital in Sorocaba, São Paulo, Brazil was evaluated over a period of two years. By using biotyping, serotyping and ribotyping, 27 distinct clones were differentiated among 76 strains isolated between 1993-94, from clinical specimens of hospitalized patients. Two clones, 2:O4:A (biotype:serotype:ribotype) and 2:O29:A accounted for the majority of strains widely disseminated in the units during 1993. The introduction in the hospital setting, of a new clone, 6:O13:B, at the end of 1993 and its predominance through 1994 is discussed. Among 15 strains isolated from neonates, 6 (40%) belonged to the same clone, 2:O4:A. Interestingly, this clone was almost all recovered in neonatal intensive care unit, nursery and in pediatric unit. All strains were susceptible to imipenem and polymyxcin B. Multiresistant strains (up to 12 antimicrobial agents) accounted for 66.7% and 84.8% of the strains isolated in 1993 and in 1994, respectively.Foi avaliada a disseminação, durante um período de dois anos, de cepas de Acinetobacter baumannii em diferentes unidades de um hospital de Sorocaba, São Paulo.Usando as técnicas de biotipagem, sorotipagem e ribotipagem, as 76 cepas isoladas no período 1993-94, foram diferenciadas em 27 distintos clones. Dois clones, 2:O4:A (biotipo:sorotipo:ribotipo) e 2:O29:A predominaram, em 1993, entre as cepas disseminadas nas várias unidades. Observou-se no final de 1993, a introdução de um novo clone, 6:O13:B e a sua predominância em 1994. Entre as 15 cepas isoladas de recém nascidos, 6 (40%) pertenciam ao mesmo clone, 2:O4:A . A maioria das cepas desse clone foram isoladas da unidade de terapia intensiva neonatal, de berçário e de unidades pediátricas. Quanto à resistência aos agentes antimicrobianos, todas as cepas foram sensíveis à polimixina B e ao imipenen. Em 1993, 66,7% das cepas eram multi-resistentes (resistentes de 4 a 12 dos 15 antimicrobianos testados), enquanto que, em 1994, 84,8% das 46 cepas isoladas foram multi-resistentes a mais de 4 e até a 12 drogas

First Shiga Toxin-Producing Escherichia coli Isolate from a Patient with Hemolytic Uremic Syndrome, Brazil

Univ Fed Sao Paulo, Escola Paulista Med, Sao Paulo, BrazilHosp Sao Paulo, Sao Paulo, BrazilInst Adolfo Lutz Registro, Sao Paulo, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Sao Paulo, BrazilHosp Sao Paulo, Sao Paulo, BrazilWeb of Scienc