Avaliação de métodos e ocorrência de Clostridium difficile em carnes / Evaluation of methods and occurrence of Clostridium difficile in meats

AUTOR(ES)
FONTE

IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia

DATA DE PUBLICAÇÃO

09/04/2012

RESUMO

Clostridium difficile is an anaerobic bacillus responsible for intestinal deseases in individuals previouslly treated with antibiocs, who can manifest from a mild diarrhea to severe cases of pseudomembranous colitis, mainly caused by toxins A (TcdA) and B (TcdB). The infections are related to contamination in hospitals, but recent researches sugests a possible association with the consumiption of contaminated foods as C. difficile has been isolated from bovines, suines and poultries and their meat, sugesting animals as reservatories. Thus, studies are extremelly important to elucidate the transmition of the desease caused by C. difficile. Faced with few researches about this bacteria and the lack of a standard method for its isolation from food, this work is divided in three steps: 1) Evaluation of the methodology for C. difficile detection in meet (commercial bovine mince and chicken breast ¿ [Peitoralis superficialis and Peitoralis profundus] [using two procedures (treatment with alcohol and direct plating) and two selective mediums (agar Clostridium difficile moxalactan norfloxacin ¿ CDMNA and cycloserine cefoxitin fructose agar¿ CCFA)]; 2) Assessing of the occurrence of C. difficile in samples of chilled meat (bovine: commercial mince and the whole Semimembranosus; suine: whole Longuisimus dorsi; chicken: Peitoralis profundus and Peitoralis superficialis) by detection, isolation and identification of the isolated; 3) Evaluation of the toxicogenic profile of the isolated by the detection of the genes tcdA and tcdB, which are encoding of TcdA and TcdB respectivelly, and the capacity of toxine production by the isolated bacterias. From the comparison of the two proceeding above it was observed that the direct plating was more efficient and recovered a larger aumont of C. difficile than the treatment with alcohol. Furthermore, the CDMNA agar presented a higher recovery rate compared to CCFA agar. It was observed the occurrence of C. difficile in 11,5% (17/147) of the analyzed samples, comprising 80 isolates, of which 41,2% (33/83) showed a positive response for at least one virulence gene (A-B+), or for both genes (A+B-). In addition, there was a 70,5% concordance between the phenotypic and genotypic tests used to detect toxins. In this way, it is suggested that foods of animal origin are a potential source of transmission of C. difficile for humans

ASSUNTO(S)

toxinas esporos reação em cadeia de polimerase diarreia toxins pathogen spores polymerase chain reaction diarrhore

ACESSO AO ARTIGO

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