RESUMO Objetivos: avaliar a carga microbiana e a aderência de Escherichia coli em diferentes áreas da superfície de instrumento cirúrgico exposto à contaminação experimental ao longo do tempo. Métodos: estudo experimental em que fragmentos de pinças crile (serrilha, haste e cremalheira) foram contaminados por imersão em Tryptic Soy Broth, contendo 106 UFC/mL de E. coli, por 1, 2, 4, 6, 8, 12 e 24 horas. A carga microbiana e a aderência bacteriana foram avaliadas com uso de cultura microbiológica e microscopia eletrônica de varredura, respectivamente. Resultados: verificou-se aumento da carga microbiana no instrumento cirúrgico, proporcional ao intervalo de contaminação, variando de 102 após 1 hora a 105 UFC/cm2 em 24 horas. A presença de exapolissacarídeo foi detectada após 2 horas de contaminação. Conclusões: carga microbiana e aderência de E. coli aumentaram ao longo do tempo, atingindo 105 UFC/cm2 após 24 horas de contaminação, iniciandose formação de biofilme após 2 horas.

ABSTRACT Objectives: to evaluate the microbial load and adherence of Escherichia coli in different areas of the surgical instrument surface exposed to experimental contamination over time. Methods: experimental study in which fragments of crile forceps (serrated, rod and rack) were contaminated by immersion in Tryptic Soy Broth, containing 106 CFU/mL of E. coli, for 1, 2, 4, 6, 8, 12 and 24 hours. Microbial load and bacterial adherence were evaluated using microbiological culture and scanning electron microscopy, respectively. Results: there was an increase in the microbial load on the surgical instrument, proportional to the contamination interval, ranging from 102 after 1 hour to 105 CFU/cm2 in 24 hours. The presence of exopolysaccharide was detected after two hours of contamination. Conclusions: microbial load and adhesion of E. coli increased over time, reaching 105 CFU/cm2 after 24 hours of contamination, starting biofilm formation after two hours.

RESUMEN Objetivos: evaluar la carga microbiana y adherencia de Escherichia coli en diferentes áreas de la superficie de instrumento quirúrgico expuesto a la contaminación experimental a lo largo del tiempo. Métodos: estudio experimental en que fragmentos de tenacillas quirúrgicas (sierra, asta y cremallera), contaminados por inmersión en Tryptic Soy Broth, conteniendo 106 UFC/mL de E. coli, por 1, 2, 4, 6, 8, 12 y 24 horas. La carga microbiana y la adherencia bacteriana evaluadas con uso de cultivo y microscopia electrónica de barredura, respectivamente Resultados: verificó aumento de la carga microbiana en el instrumento quirúrgico, proporcional al intervalo de contaminación, variando de 102 tras 1 hora a 105 UFC/cm2 en 24 horas. La presencia de polisacárido detectada tras 2 horas de contaminación. Conclusiones: carga microbiana y adherencia de E. coli aumentaron a lo largo del tiempo, atingiendo 105 UFC/cm2 tras 24 horas de contaminación, iniciándose formación de biopelícula tras 2 horas.

The association between worm infections and bacterial diseases has only recently been emphasized. This study examined the effect of experimental Angiostrongylus costaricensis infection on endogenous intestinal flora of Swiss Webster mice. Eight mice aging six weeks were selected for this experiment. Four were infected with A. costaricensis and the other four were used as controls. Twenty eight days after the worm infection, all mice in both groups were sacrificed and samples of the contents of the ileum and colon were obtained and cultured for aerobic and anaerobic bacteria. In the mice infected with A. costaricensis there was a significant increase in the number of bacteria of the endogenous intestinal flora, accompanied by a decrease in the number of Peptostreptococcus spp. This alteration in the intestinal flora of mice infected by the nematode may help to understand some bacterial infections described in humans.