Avaliação da sensibilidade de cepas de Escherichia coli isoladas de mexilhões (Perna perna linnaeus, 1758) à antimicrobianos

Abstract

Nos tempos modernos, uma das grandes preocupações da comunidade científica é a grande probabilidade de colonização da mucosa intestinal do homem, através da ingestão de alimentos contaminados, por microrganismos extremamente resistentes à maioria dos antimicrobianos utilizados no tratamento de enfermidades.O uso de antibióticos foi revolucionário no tratamento das infecções bacterianas e crucial para a redução da mortalidade (NATARO; KAPER, 1998). Entretanto, seu uso abusivo e indiscriminado, tanto em humanos (CHUC et al., 2002) quanto na medicina veterinária (COSTA et al., 2006), pode ter contribuído para o aumento da resistência antimicrobiana (CHUC et al., 2002). Essa resistência relaciona-se, ainda, à produção de enzimas (β-lactamases e β-lactamases de amplo espectro), que atuam sobre a estrutura das penicilinas, inativando-as, característica que constitui um mecanismo de defesa desses agentes. Emery e Weymouth (1997) constataram que a síntese dessas enzimas era codificada por genes presentes AbstractForty-four strains of Escherichia coli isolated from mussel samples collected in the city of Niterói, State of Rio de Janeiro, were evaluated in terms of antimicrobial sensitivity. Twenty-four antimicrobials were tested, and different standards of behavior could be observed. All strains evaluated presented total sensitivity to only 41.66% of the antimicrobials (R, Ac, C, To, Fx, Cz, Ct, NT, Cp, and GE) and total resistance to 4.16% of the antimicrobials (Ca). The strain number eighteen presented sensitivity to 95.83% of the antimicrobials, whereas the strain number thirty presented resistance to 41.66% of the antimicrobials. Based on the results obtained, it is important to consider the health risk posed by raw fish consumption, especially filter-feeding bivalves, contaminated by microorganisms resistant to different antimicrobials since they may be involved in processes of human reinfection causing gastroenteritis.

Molecular characterization and evaluation of antimicrobial susceptibility of enteropathogenic E. coli (EPEC) isolated from minas soft cheese

“…Although multi-resistance E. coli cases have been reported (BACCARO et al, 2002;GUERRA et al, 2003;DIAS et al, 2010), such feature was not observed in this study.…”

“…High resistance to ampicillin was described by Baccaro et al (2002) and Blanco et al (2006); however, Dias et al (2010) found only 2.27% of resistance to this antimicrobial. The E. coli strains isolated by Paneto et al (2007) in Minas soft cheese showed higher cephalothin resistance (69%) and only 29% to ampicillin.…”

“…The results of antimicrobial susceptibility evaluation are described in Table 2. Dias et al (2010) reported that E. coli strains show high variability and high capacity to acquire resistance genes according to Gonçalves (2009). This association of factors can explain the divergences observed in the study of this microorganism.…”

“…A substantial progress and development has been achieved based on nucleic acids analysis; thus the amplification of specific DNA sequences of those genes has been used as an appropriate tool for the challenging task of finding pathogenic E. coli in clinical samples (GÓMEZ-DUART et al, 2009) and food samples (LÓPEZ-SAUCEDO et al, 2003). Furthermore, another concern is the probability of human intestinal mucosa colonization by microorganisms which are resistant to the antimicrobial frequently used to treat illnesses caused by ingestion of contaminated food (DIAS et al, 2010).…”

“…Cases of pathogenic E. coli strains showing different resistance patterns (COSTA et al, 2006) and cases of multi-resistant strains (GUERRA et al, 2003;DIAS et al, 2010) have been reported.…”