Antibiotic resistance and virulence factors among Escherichia coli isolates from avian organic fertilizer / Resistência a antibióticos e fatores de virulência entre isolados de Escherichia coli provenientes de fertilizante orgânico aviário

ABSTRACT: Brazilian poultry industry generates large amounts of organic waste, such as chicken litter, which is often used in agriculture. Among the bacteria present in organic fertilizer are members of the Enterobacteriaceae family, such as Escherichia coli. The aim of this study was to analyze the profile of virulence factors and antimicrobial resistance of E. coli isolates from avian organic fertilizer. A total of 47 E. coli strains were tested through Polymerase chain reaction to detect virulence genes (hlyF, iss, ompT, iutA and iroN). Fourteen antimicrobials were used to test antimicrobial susceptibility in the strains. Genes characteristic of Avian Pathogenic E. coli (APEC) were reported among the strains, with the hlyF, iss and ompT genes being the most prevalent. The isolates showed high resistance (˃50%) to tetracycline, gentamicin, cefotaxime, nitrofurantoin, trimethoprim-sulfamethoxazole and ampicillin. Multidrug resistance was reported in a great number of strains (>70%). The results showed the presence of APEC cells with virulence genes and antimicrobial resistance after 15 days of the windrowing process in poultry houses, it means this process should be improved to eliminate these cells.

RESUMO: A indústria avícola brasileira gera grandes quantidades de resíduos orgânicos, como a cama de frango, utilizada frequentemente na agricultura. Entre as bactérias presentes neste fertilizante orgânico estão os membros da família Enterobacteriaceae, entre eles a Escherichia coli. O objetivo deste estudo foi analisar o perfil de fatores de virulência e resistência antimicrobiana de isolados de E. coli provenientes do fertilizante orgânico aviário. Um total de 47 cepas de E. coli foram testadas por meio da reação em cadeia da polimerase para detectar genes de virulência (hlyF, iss, ompT, iutA e iroN). Quatorze antimicrobianos foram utilizados para testar a susceptibilidade antimicrobiana nos isolados. Genes característicos de E. coli Patogênica Aviária (APEC) foram encontrados entre os isolados, sendo os genes hlyF, iss e ompT os mais prevalentes. Os isolados apresentaram alta resistência (˃50%) à tetraciclina, gentamicina, cefotaxima, nitrofurantoína, trimetoprima-sulfametoxazole e ampicilina. Múltipla resistência a drogas antimicrobianas foi encontrada em grande número de isolados (>70%). Os resultados obtidos mostraram a presença de células APEC portando genes de virulência e resistência a antimicrobianos após 15 dias de processo de empilhamento nas granjas, indicando que o processo necessita de um aperfeiçoamento para eliminar estas células.

Occurrence of non-O157 Shiga toxin-encoding Escherichia coli in artisanal mozzarella cheese in Brazil: risk factor associated with food workers

Abstract Mozzarella cheese is considered a safe food due to the high temperature treatment used in the traditional process of stretching into hot water; however, a post-process contamination during the cheese manufacture or during the processing (before distribution) could occur. This study investigated the occurrence of Shiga toxin-encoding Escherichia coli (STEC) strains in homemade-mozzarella cheese. In total, 59 raw milk cheese samples collected at a local producer in the Jequitinhonha Valley (Northeast of Minas Gerais, Brazil) were submitted for microbiological analysis, and 38 (64.4%) tested positive for E. coli. Then, 147 strains of E. coli were isolated from positive samples and screened by polymerase chain reaction for the presence of the genes encoding the following virulence factors: stx1 and stx 2 (verotoxin types 1 and 2) and eae (intimin). All the isolates were negative for the stx 2, 14 isolates (9.5%) were positive for the stx1 gene, and 11 of them also harbored the eae gene. A food worker was probably involved in cheese contamination during the manufacture schedule. While the development of STEC infection in humans is not completely understood, all STEC- contaminated food can be considered potentially hazardous.

Survey of Minas frescal cheese from Southwest Minas Gerais for virulence factors and antimicrobial resistance in Escherichia coli isolates / Avaliação em queijos Minas frescal provenientes do Sudoeste de Minas Gerais da presença de fatores de virulência e resistência antimicrobiana em isolados de Escherichia coli

The soft cheese Minas frescal is one of the most popular cheese in Brazil, which is typically manufactured in small dairy farms under unsatisfactory hygiene conditions. To assess the risk involved in consumption of this cheese, virulence markers were investigated in 330 Escherichia coli strains isolated from 30 Minas frescal cheeses inspected by official government agency (SIF - serviço de inspeção federal), from 50 cheeses not inspected by SIF and 31 cheeses not inspected by SIF with spice added, all of them collected in the southwest of Minas Gerais State. The E. coli isolates were screened for the presence of Shiga toxin-encoding (stx 1 and stx 2), intimin (eae) genes and for the presence of (pap, sfa, afa) genes related to adhesion in epithelial cells. The only gene detected by PCR was the sfa gene at one isolate. The strains were also screened for resistance to 9 antimicrobial drugs. Predominant resistance was to cephalothin, tetracycline and streptomycin. Multidrug resistance was found among isolates from cheese with SIF (16.6%), cheese without SIF (8.0%) and cheese without SIF with spice added (30.0%) what is a reason for concern due to the high consumption of raw milk cheese by the Brazilian population.

O queijo Minas frescal é um dos queijos mais populares no Brasil, ele é tipicamente manufaturado em pequenas fazendas de leite, em condições higiênicas insatisfatórias. Para verificar o risco envolvido no consumo deste queijo, marcadores de virulência foram investigados em 330 cepas de isoladas de 30 queijos Minas frescal, inspecionados pela agencia governamental oficial (SIF- serviço de inspeção federal), de 50 queijos não inspecionados pelo SIF e de 31 queijos não inspecionados pelo SIF e com condimentos adicionados. Todos eles foram coletados na região sudeste do Estado de Minas Gerais. As cepas de E. coli foram examinadas para a presença de genes codificadores de Shiga toxina (stx1 e stx 2), gene da intimina (eae) e também para a presença dos genes (pap, sfa, afa) relacionados com a adesão em células epiteliais. O único gene detectado por PCR foi sfa em um isolado. As cepas também foram examinadas para a resistência a nove fármacos antimicrobianos. As resistências predominantemente detectadas foram para cefalotina, tetraciclina e estreptomicina. A resistência a múltiplas drogas identificadas entre as cepas de E. coli, provenientes de queijo com SIF (16,6%), queijo sem SIF (8,0%) e queijo sem SIF com condimentos adicionados (30,0%), o que representa um motivo de preocupação, devido ao elevado consumo pela população Brasileira de queijos feitos de leite não pasterurizado.

Phenotypical characterization and adhesin identification in Escherichia coli strains isolated from dogs with urinary tract infections

Pathogenic strains of Escherichia coli are the most common bacteria associated with urinary tract infections in both humans and companion animals. Standard biochemical tests may be useful in demonstrating detailed phenotypical characteristics of these strains. Thirteen strains of E. coli isolated from dogs with UTIs were submitted to biochemical tests, serotyping for O and H antigens and antimicrobial resistance testing. Furthermore, the presence of papC, sfa, and afa genes was evaluated by PCR, and genetic relationships were established using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). The antimicrobial that showed the highest resistance rate among the isolates was nalidixic acid (76.9%), followed by cephalotin (69.2%), sulfamethoxazole + trimethoprim (61.5%), tetracycline (61.5%), streptomycin (53.8%), ciprofloxacin (53.8%), ampicillin (46.2%), gentamicin (30.8%) and chloramphenicol (23.1%). No isolate was resistant either to meropenem or nitrofurantoin. Among the five clusters that were identified using ERIC-PCR, one cluster (A) had only one strain, which belonged to a serotype with zoonotic potential (O6:H31) and showed the genes papC+, sfa+, afa-. Strains with the genes papC-, sfa+, afa- were found in two other clusters (C and D), whereas all strains in clusters B and E possessed papC-, sfa-, afa- genes. Sucrose and raffinose phenotypic tests showed some ability in discriminating clusters A, B and C from clusters D and E.

Phenotypical characterization and adhesin identification in Escherichia coli strains isolated from dogs with urinary tract infections.

Pathogenic strains of Escherichia coli are the most common bacteria associated with urinary tract infections in both humans and companion animals. Standard biochemical tests may be useful in demonstrating detailed phenotypical characteristics of these strains. Thirteen strains of E. coli isolated from dogs with UTIs were submitted to biochemical tests, serotyping for O and H antigens and antimicrobial resistance testing. Furthermore, the presence of papC, sfa, and afa genes was evaluated by PCR, and genetic relationships were established using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). The antimicrobial that showed the highest resistance rate among the isolates was nalidixic acid (76.9%), followed by cephalotin (69.2%), sulfamethoxazole + trimethoprim (61.5%), tetracycline (61.5%), streptomycin (53.8%), ciprofloxacin (53.8%), ampicillin (46.2%), gentamicin (30.8%) and chloramphenicol (23.1%). No isolate was resistant either to meropenem or nitrofurantoin. Among the five clusters that were identified using ERIC-PCR, one cluster (A) had only one strain, which belonged to a serotype with zoonotic potential (O6:H31) and showed the genes papC+, sfa+, afa-. Strains with the genes papC-, sfa+, afa- were found in two other clusters (C and D), whereas all strains in clusters B and E possessed papC-, sfa-, afa- genes. Sucrose and raffinose phenotypic tests showed some ability in discriminating clusters A, B and C from clusters D and E.

Analysis of Escherichia coli isolated from bovine mastitic milk / Análise de Escherichia coli isolada de leite de vacas com mastite

Mastitis has been recognized for some time as the most costly disease in dairy herds. From February to November 2004, 670 samples of bovine mastitic milk from which 231 Escherichia coli strains were isolated, were collected from two Brazilian states. The strains were screened for the presence of Shiga toxin-producing (stx 1 and stx 2) and intimin (eae) genes. Twenty (8.6 percent) strains were detected by PCR to harbor the Shiga toxin genes (8 the stx 1 gene, 12 the stx 2 gene and none both of them). Two (0.8 percent) of the Escherichia coli strains studied were eae positive non Shiga toxin-producing. The strains were also examined for resistance to 12 antimicrobial agents. The predominantly observed resistance was to tetracycline (92.2 percent), streptomycin (90.4 percent), nalidixic acid (88.3 percent), amikacin (86.5 percent) and cephalothin (84.8 percent). Multidrug resistance was found among 152 isolates (65.8 percent).

A um longo tempo a mastite tem sido reconhecida como a doença que provoca as maiores perdas econômicas nos rebanhos leiteiros. De fevereiro a novembro de 2004, foram coletadas 670 amostras de leite mastítico de vacas, provenientes de dois estados brasileiros, das quais foram isoladas 231 cepas de Escherichia coli. Estas cepas foram analisadas para a detecção dos genes de produção de Shiga toxina (stx 1 e stx 2) e do gene da intimina (eae). Vinte cepas (8,6 por cento) foram detectadas através de PCR como contendo os genes da Shiga toxina (8 stx 1, 12 stx 2 e nenhuma delas ambos os genes). Duas cepas (0,8 por cento) de E. coli eram eae positivo não produtoras de Shiga toxina. As cepas de E. coli foram também examinadas para detectar a resistência a 12 agentes antimicrobianos. As resistências mais freqüentes foram para tetraciclina (92,2 por cento), estreptomicina (90,4 por cento), ácido nalidixico (88,3 por cento), amicacina (86,5 por cento) e cefalotina (84,8 por cento). A resistência a múltiplas drogas foi encontrada em 152 cepas (65,8 por cento).

Beef carcass contamination by Shiga toxin-producing Escherichia coli strains in an abattoir in Brazil: characterization and resistance to antimicrobial drugs.

A survey was performed to estimate the frequency of Escherichia coli and Shiga toxin-producing E. coli (STEC) in carcasses obtained from an abattoir in Brazil between February 2006 and June 2007. A total of 216 beef carcasses were sampled at three stages of the slaughter process--preevisceration, postevisceration, and postprocessing--during the rain and dry seasons, respectively. Of the carcasses sampled, 58% were preevisceration E. coli positive, 38% were postevisceration positive, and 32% postprocessing positive. At the postprocessing stage, the isolation of E. coli was twice as high in the rain season. E. coli was isolated from 85 carcasses of which only 3 (1.4%) were positive for stx-encoding genes. No E. coli O157 serogroup isolates were detected. No antimicrobial resistance was found in nine of the isolates (10% of the total). The most frequent resistances were seen against cephalothin (78%), streptomycin (38%), nalidixic acid (36%), and tetracycline (30%). Multidrug resistance (MDR) to three or more antimicrobial agents was determined in 28 (33%) E. coli isolates. The presence of STEC and MDR strains among the isolates in the beef carcasses emphasizes the importance of proper handling to prevent carcass contamination.

Occurrence of non-O157 Shiga toxin-producing Escherichia coli in dogs with diarrhea / Ocorrência de Escherichia coli não-O157 Shigatoxigênica em cachorros com diarréia

Shiga toxigenic Escherichia coli (STEC) and Attaching and effacing E. coli (AEEC) have been associated with diarrhea illness in dogs. From January to December 2006, 92 E. coli isolates from 25 diarrheic dogs were analyzed, by screening for the presence of Shiga toxin-producing (stx 1 and stx 2) and intimin (eae) genes. Twelve isolates were detected by PCR to harbor the Shiga toxin genes (7 the stx 1 (7.6 percent); 5 the stx 2 (5.4 percent); and none both of them). Nine (9.8 percent) of the E. coli isolates studied were eae positive non Shiga toxin-producing. Thirteen (62.0 percent) isolates, carrying stx or eae gene, also showed a hemolysin production. The strains with virulence genes were also examined for resistance to 12 antimicrobial agents. Resistances to cephalothin (85.7 percent), streptomycin (81.0 percent), amoxicillin (71.4 percent) and gentamicin (71.4 percent) were predominantly observed.

Escherichia coli Shiga toxigênica (STEC) e E. coli Attaching- effacing (AEEC) têm sido associadas à doença diarréica em cachorros. Entre janeiro e dezembro de 2006, 92 cepas de E. coli isoladas de 25 cachorros diarréicos foram examinadas. As cepas foram analisadas para a detecção dos genes produtores de Shiga toxina (stx 1 e stx 2) e da intimina (eae). Por meio de PCR foi observado que sete cepas (7,6 por cento) portavam o gene stx 1, cinco cepas (5,4 por cento) carregavam o gene stx 2 e nenhum cepa apresentou ambos os genes associados. Nove cepas de E. coli (9,8 por cento) apresentaram o gene eae isoladamente. Treze das cepas (62,0 por cento) que apresentaram os genes stx ou eae também apresentaram a produção de a hemolisina. As cepas que apresentaram genes de virulência foram também examinadas em relação à resistência a 12 agentes antimicrobianos. As resistências mais comuns foram para cefalotina (85,7 por cento), estreptomicina (81,0 por cento), amoxicilina (71,4 por cento) e gentamicina (71,4 por cento).

Isolation of extraintestinal pathogenic Escherichia coli from diarrheic dogs and their antimicrobial resistance profile / Isolamento de Escherichia coli extraintestinal patogênica de cachorros diarréicos e seu perfil de resistência antimicrobiana

From January to December 2006, 92 Escherichia coli isolates from 25 diarrheic dogs were analyzed by screening for the presence of adhesin-encoding genes (pap, sfa, afa), hemolysin and aerobactin genes. Virulence gene frequencies detected in those isolates were: 12 percent pap, 1 percent sfa, 10 percent hemolysin and 6.5 percent aerobactin. Ten isolates were characterized as extraintestinal pathogenic E. coli (ExPEC) strains; all showed a multidrug resistance phenotype that may represent a reason for concern due the risk of dissemination of antimicrobial resistant genes to the microbiota of human beings.

Entre Janeiro e dezembro de 2006, 92 cepas de Escherichia coli isoladas de 25 cachorros diarréicos foram analisadas para a detecção de genes codificadores de adesinas (pap, sfa e afa), hemoisina e aerobactina. As freqüências dos genes de virulência detectadas nestas cepas foram: 12 por cento pap, 1 por cento sfa, 10 por cento hemolisina e 6,5 por cento aerobactina. Dez cepas foram caracterizadas como E. coli extraintestinal patogênica (ExPEC) e todas as cepas apresentaram um fenótipo de multiresistência, o que pode representar um motivo de preocupação, por causa do risco de disseminação de genes de resistência a drogas antimicrobianas para a microbiota dos seres humanos.

Isolation of Pseudomonas aeruginosa strains from dental office environments and units in Barretos, state of São Paulo, Brazil, and analysis of their susceptibility to antimicrobial drugs / Isolamento de cepas de Pseudomonas aeruginosa provenientes do meio ambiente e de equipos dentarios em clinicas dentarias em Barretos, São Paulo, Brasil; analises da susceptibilidade das cepas a drogas antimicrobianas

A wide variety of opportunistic pathogens has been detected in the tubing supplying water to odontological equipment, in special in the biofilm lining of these tubes. Among these pathogens, Pseudomonas aeruginosa, one of the leading causes of nosocomial infections, is frequently found in water lines supplying dental units. In the present work, 160 samples of water, and 200 fomite samples from forty dental units were collected in the city of Barretos, State of São Paulo, Brazil and evaluated between January and July, 2005. Seventy-six P. aeruginosa strains, isolated from the dental environment (5 strains) and water system (71 strains), were tested for susceptibility to six antimicrobial drugs most frequently used against P. aeruginosa infections. Susceptibility to ciprofloxacin, followed by meropenem was the predominant profile. The need for effective means of reducing the microbial burden within dental unit water lines is emphasized, and the risk of exposure and cross-infection in dental practice, in special when caused by opportunistic pathogens like P. aeruginosa, are highlighted.

Uma ampla variedade de patógenos oportunistas tem sido detectadas nos tubos de alimentação de água dos equipos odontológicos, particularmente no biofilme formado na superfície do tubo. Entre os patógenos oportunistas encontrados nos tubos de água, Pseudomonas aeruginosa é reconhecida como uma das principais causadoras de infecções nosocomiais. Foram coletadas 160 amostras de água e 200 amostras de fomites em quarenta clinicas odontológicas na cidade de Barretos, São Paulo, Brasil, durante o período de Janeiro a Julho de 2005. Setenta e seis cepas de P. aeruginosa, isoladas a partir dos fomites (5 cepas) e das amostras de água (71 cepas), foram analisadas quanto à susceptibilidade à seis drogas antimicrobianas freqüentemente utilizadas para o tratamento de infecções provocadas por P. aeruginosa. As principais suscetibilidades observadas foram para a ciprofloxacina, seguida pelo meropenem. A necessidade de um mecanismo efetivo para reduzir a contaminação bacteriana dentro dos tubos de alimentação de água dos equipos odontológicos foi enfatizada, e o risco da exposição ocupacional e infecção cruzada na prática odontológica, em especial quando causada por patógenos oportunistas como a P. aeruginosa foi realçado.

Isolation of extraintestinal pathogenic Escherichia coli from diarrheic dogs and their antimicrobial resistance profile.

From January to December 2006, 92 Escherichia coli isolates from 25 diarrheic dogs were analyzed by screening for the presence of adhesin-encoding genes (pap, sfa, afa), hemolysin and aerobactin genes. Virulence gene frequencies detected in those isolates were: 12% pap, 1% sfa, 10% hemolysin and 6.5% aerobactin. Ten isolates were characterized as extraintestinal pathogenic E. coli (ExPEC) strains; all showed a multidrug resistance phenotype that may represent a reason for concern due the risk of dissemination of antimicrobial resistant genes to the microbiota of human beings.

Isolation of Pseudomonas aeruginosa strains from dental office environments and units in Barretos, state of São Paulo, Brazil, and analysis of their susceptibility to antimicrobial drugs.

A wide variety of opportunistic pathogens has been detected in the tubing supplying water to odontological equipment, in special in the biofilm lining of these tubes. Among these pathogens, Pseudomonas aeruginosa, one of the leading causes of nosocomial infections, is frequently found in water lines supplying dental units. In the present work, 160 samples of water, and 200 fomite samples from forty dental units were collected in the city of Barretos, State of São Paulo, Brazil and evaluated between January and July, 2005. Seventy-six P. aeruginosa strains, isolated from the dental environment (5 strains) and water system (71 strains), were tested for susceptibility to six antimicrobial drugs most frequently used against P. aeruginosa infections. Susceptibility to ciprofloxacin, followed by meropenem was the predominant profile. The need for effective means of reducing the microbial burden within dental unit water lines is emphasized, and the risk of exposure and cross-infection in dental practice, in special when caused by opportunistic pathogens like P. aeruginosa, are highlighted.

Presence of extraintestinal pathogenic Escherichia coli in butcheries in Taquaritinga, SP, Brazil

The study was conducted in twenty-three butcheries in the city of Taquaritinga, State of São Paulo, Brazil, surveyed during a 10 months period. Among two hundred and eighty-seven Escherichia coli strains isolated from samples of ground beef, meat-grinding-machines and the hands of manipulators, five were recognized as extraintestinal pathogenic E. coli (ExPEC), showing virulence factors (P and S fimbriae, hemolysin and aerobactin) and presenting multidrug resistance. Retail-sold food may constitute an important vehicle for the dissemination of ExPEC in communities, giving rise to reasons for concern.

O trabalho foi desenvolvido em 23 açougues em Taquaritinga, Estado de São Paulo, Brasil, durante um período de 10 meses. De duzentas e oitenta e sete cepas de E.coli isoladas de carne moída, moedor de carne e mãos de manipuladores de carne, cinco foram caracterizadas como E. coli patogênica extraintestinal (ExPEC) apresentando fatores de virulência (fimbria P e S, hemolisina e aerobactina), assim como multiresistencia a drogas antimicrobianas. Retalhos de carne podem ser um veiculo importante para a disseminação de ExPEC, o que representa um motivo de preocupação.

Isolation of Shiga toxigenic Escherichia coli from butcheries in Taquaritinga city, State of São Paulo, Brazil

Shiga toxigenic Escherichia coli (STEC) has been implicated as the cause of several human diseases. Samples (ground beef, grinding-machines and human hands) from 23 butcheries were assayed for E. coli using standard microbiological methods, and 287 isolates were submitted to polymerase chain reaction for the detection of stx 1, stx 2 and eae genes. Four STEC isolates were recovered, two from ground beef and two from grinding-machines; all harbored the stx 2 gene and were negative for the eae gene. All E. coli isolates including the four STEC were screened for antibiotic resistance. High levels of resistance against several antimicrobial agents were detected; those most commonly observed were to tetracycline (76.6 percent), amoxicillin (64.1 percent) and cephalothin (58.8 percent). Such high levels of antimicrobial resistance highlight the need for a more rational use of these agents in cattle.

Escherichia coli Shiga toxigênica (STEC) tem sido responsabilizada como o agente etiológico de diversas doenças nos seres humanos. Neste estudo foram analisadas amostras provenientes de 23 açougues (carne moída, moedor de carne e mãos de manipuladores) visando o isolamento de cepas de E. coli utilizando os métodos microbiológicos tradicionais. Um total de 287 cepas de E. coli, isoladas destas amostras, foram submetidas a reação em cadeia da polimerase para a detecção dos genes stx 1, stx 2 e eae. Foram identificadas 4 cepas STEC, 2 provenientes de carne moída e 2 provenientes do moedor de carne, todas as cepas apresentando o gene stx 2 e negativas para a presença do gene eae. Todas as cepas de E. coli, incluindo as 4 cepas STEC, foram examinadas para verificar a resistência antimicrobiana. Foram detectados altos níveis de resistência a diferentes agentes antimicrobianos, sendo as resistências mais elevadas para a tetraciclina (76,6 por cento), amoxicilina (64,1 por cento) e cefalotina (58,8 por cento). Estes altos índices de resistência ressaltam a necessidade de uma utilização mais racional destes agentes no gado bovino.

Multidrug-resistant urinary tract isolates of escherichia coli from Ribeirão Preto, São Paulo, Brazil

Multiple resistances to antimicrobial drugs arising in Escherichia coli isolates may complicate therapeutic management of urinary tract infection (UTI) by this organism. In order to assess the multidrug resistance (MDR) among urinary E. coli isolates, we have tested 11 antimicrobial drugs against 67 isolates from outpatients attended in a tertiary-care teaching hospital and of 78 isolates from a municipal health unit, respectively in Ribeirão Preto, State of São Paulo, Brazil. Seventy-six percent and 22 percent of the isolates from the tertiary-care hospital and the municipal unit, respectively, were resistant to three or more different classes of agents, and were considered to present MDR. Among the isolates from the hospital patients, 73.0 percent, 65.0 percent, 58.0 percent, 58.0 percent and 31.0 percent were resistant to tetracycline, ampicillin, cephalothin, trimethoprim-sulfamethoxazole (TMP/SMX) and norfloxacin, respectively; resistance from the municipal unit patients were 31.0 percent, 37.0 percent, 8.0 percent, 29.0 percent and 12.0 percent respectively, to the same drugs. The predominant phenotype among the MDR isolates presented is ampicillin, TMP/SMX and tetracycline resistance. The high prevalence of drug resistance among UTI patients calls for continuous surveillance to assure effective control of this infection.

Infecção experimental em suínos jovens com Leptospira interrogans sorovar wolffi: determinação de parâmetros bioquímicos / Experimental infection by Leptospira interrogans serovar wolffi in young pigs: determination of biochemical parameters

Um estudo sobre infecção experimental foi realizado em oito suínos, com idade média de 90 dias, machos castrados, da raça Wessex, e distribuídos em dois grupos de quatro suínos cada. Durante 36 dias, foram analisadas as alterações bioquímicas nos soros dos suínos dos dois grupos. O Grupo I foi mantido como testemunho e recebeu 5,0mL de solução fisiológica estéril por via intravenosa (veia cava craniana) e, no Grupo II, os suínos foram inoculados pela mesma via com 5,0mL de cultura de Leptospira interrogans sorovar wolffi , amostra L-10 selvagem isolada de tatu (Dasypus novemcinctus), contendo 1,0 x 10(8) leptospiras/mL. A partir do terceiro dia após a inoculação e em intervalos de 72 horas até o décimo oitavo dia, foram feitas coletas de sangue, sem anticoagulante, dos animais inoculados e testemunhas. Os parâmetros bioquímicos analisados foram: bilirrubina total, direta e indireta, ácidos graxos, glicose e proteínas plasmáticas. Foi detectado um aumento da bilirrubina direta no terceiro dia e um aumento no sexto dia da bilirrubina total e indireta após a inoculação. As dosagens de glicose, ácidos graxos e proteínas plasmáticas apresentaram uma diminuição a partir do terceiro dia da inoculação. Com os resultados obtidos, pode-se concluir que o aumento das taxas de bilirrubinas levam a uma definição de um diagnóstico de hemólise aguda, e que a hipoglicemia, a hipolipidemia e a hipoproteinemia podem estar relacionadas com lesões hepáticas e a uma septcemia.Todas as dosagens em todos os animais retornaram aos seus valores normais a partir do décimo quinto dia.

Eight, 90 days old pigs, of the Wessex lineage all castrated male were used in experiment, divided into two groups of four animals. Biochemical alterations in the serum of the animals were analyzed in both groups during 36 days. Control (Group I) received 5.0mL of a 0.9 percent sterile sodium chloride solution by intracranial vein injection; Group II animals were inoculated by the same way with 5.0mL of a cell culture containing 1.0x10(8)cells/mL of Leptospira interrogans sorovar wolffi, wild strain L-10, isolated from a wild especies of brazilian "armadillo" (Dasypus novemcinctus). Three days after inoculation, blood was collected without anticoagulant; the same process was repeated at 72 hours intervals during eighteen days in both, control and experimental groups. Quantitative biochemical parameters were direct, indirect and total bilirubin, fatty acids and serum proteins. The experimental animals showed an increase of direct bilirubin three days after inoculation. Increases in indirect and total bilirubin were, also, observed after six days. Glucose, fatty acids and serum proteins decreased after the third day of inoculation. In conclusion, the increase in bilirubin levels could be due to acute hemolysis; hypoglycemia, hypolipidemia and hypoproteinemia that could be related to hepatic lesions and septicemia. All parameters returned to normal levels after fifteen days, in all animals tested.

Multidrug-resistant urinary tract isolates of escherichia coli from Ribeirão Preto, São Paulo, Brazil.

Multiple resistances to antimicrobial drugs arising in Escherichia coli isolates may complicate therapeutic management of urinary tract infection (UTI) by this organism. In order to assess the multidrug resistance (MDR) among urinary E. coli isolates, we have tested 11 antimicrobial drugs against 67 isolates from outpatients attended in a tertiary-care teaching hospital and of 78 isolates from a municipal health unit, respectively in Ribeirão Preto, State of São Paulo, Brazil. Seventy-six percent and 22% of the isolates from the tertiary-care hospital and the municipal unit, respectively, were resistant to three or more different classes of agents, and were considered to present MDR. Among the isolates from the hospital patients, 73.0%, 65.0%, 58.0%, 58.0% and 31.0% were resistant to tetracycline, ampicillin, cephalothin, trimethoprim-sulfamethoxazole (TMP/SMX) and norfloxacin, respectively; resistance from the municipal unit patients were 31.0%, 37.0%, 8.0%, 29.0% and 12.0% respectively, to the same drugs. The predominant phenotype among the MDR isolates presented is ampicillin, TMP/SMX and tetracycline resistance. The high prevalence of drug resistance among UTI patients calls for continuous surveillance to assure effective control of this infection.

Detection of Streptococcus mutans and Streptococcus sobrinus in dental plaque samples from Brazilian preschool children by polymerase chain reaction.

The purposes of this study were to detect S. mutans and S. sobrinus by polymerase chain reaction (PCR) amplification, and to relate their presence to the incidence of dental caries in 42 Brazilian preschool children. Dental plaque samples were collected from the cervical margin of all erupted teeth of 5-6 years old children with primary dentition, using a sterile explorer. Examination of the dmft (decayed, missing, filled teeth) index, performed following the World Health Organization (WHO) caries diagnostic criteria, showed a 2.71 score. Prevalence of S. mutans and S. sobrinus was respectively, of 85.7% and 14.3%; no dental plaque sample was either positive or negative for both bacterial species. Children harboring either S. mutans or S. sobrinus presented the same caries prevalence. PCR showed good discriminative ability for differentiation between these species, and suggested that it is a technique suitable for epidemiological studies on mutans streptococci.

Detection of streptococcus mutans and streptococcus sobrinus in dental plaque samples from Brazilian preschool children by polymerase chain reaction

The purposes of this study were to detect S. mutans and S. sobrinus by polymerase chain reaction (PCR) amplification, and to relate their presence to the incidence of dental caries in 42 Brazilian preschool children. Dental plaque samples were collected from the cervical margin of all erupted teeth of 5-6 years old children with primary dentition, using a sterile explorer. Examination of the dmft (decayed, missing, filled teeth) index, performed following the World Health Organization (WHO) caries diagnostic criteria, showed a 2.71 score. Prevalence of S. mutans and S. sobrinus was respectively, of 85.7 percent and 14.3 percent; no dental plaque sample was either positive or negative for both bacterial species. Children harboring either S. mutans or S. sobrinus presented the same caries prevalence. PCR showed good discriminative ability for differentiation between these species, and suggested that it is a technique suitable for epidemiological studies on mutans streptococci.

A presença de Streptococcus mutans e S. sobrinus, detectadas através da técnica da reação em cadeia da polimerase (PCR) foi comparada com a incidência de cárie dental em 42 crianças pré-escolares brasileiras. As amostras da placa dental foram obtidas utilizando-se um explorador estéril, o qual foi passado na margem cervical de todos os dentes erupcionados nas crianças de 5-6 anos de idade, as quais possuíam a dentição primária. Foi realizado um exame dental para a avaliação do índice ceod (índice de dentes decíduos cariados, extraídos por cárie ou obturados) de acordo com os critérios de diagnóstico de cárie preconizados pela Organização Mundial de Saúde (OMS). O índice ceod foi de 2,71. A presença de S. mutans e S. sobrinus foi detectada em 85,7 por cento e 14,3 por cento das crianças analisadas respectivamente, nenhuma amostra da placa dental foi positiva ou negativa para a presença das duas bactérias ao mesmo tempo. As crianças que apresentavam S. mutans ou S. sobrinus isoladamente apresentaram o mesmo índice de cárie. A técnica de PCR apresentou um grande poder discriminatório entre as duas espécies o que sugere que ela é adequada para estudos epidemiológicos no grupo mutans.