Resistência antimicrobiana de Listeria monocytogenes em produtos de origem animal

Abstract

Studies relate Listeria monocytogenes to contamination of animal products in Brazil and several countries, especially associated with ready-to-eat foods. This bacterium remains a concern in causing outbreaks of listeriosis with strains with antimicrobial resistance. In this context, this study carried out a systematic review of the literature and meta-analysis to identify and compare the anti-microbial resistance of L. monocytogenes to conventional antimicrobial agents (penicillins, aminoglycosides and inhibitors of the folate pathway) and unconventional (all others) used in the treatment of listeriosis. A second step was to standardize a real-time PCR (q-PCR) to detect mecC and erma genes, responsible for providing resistance to ampicillin and erythromycin investigation of these genes in 25 strains of L. monocytogenes from chicken produced in Mato Grosso. The results show that the meta-analysis indicated no significant evidence in the world of L. monocytogenes resistance to conventional and unconventional antibiotics (p = 0.29). The heterogeneity between the studies was high (96%), indicating discrepancies between the studies. Thus, in the subgroup analysis, we found that the study site was significant for North America (p <0.00001), with no heterogeneity between the studies. The effect of the animal chain in South America was also significant for beef (p <0.00001), showing no heterogeneity and evidencing for this continent a risk of more excellent antimicrobial resistance for conventional antibiotics. In poultry meat, the general effect was also significant (p <0.00001), showing greater evidence of resistance risk for unconventional antibiotics. The subgroup analyzes showed that the locality and the animal chain were useful parameters for the meta-analysis and reduced methodological discrepancies. As for q-PCR, it was possible to standardize the detection of ermA and mecC genes in bacteria; however, the absence of these genes was verified in strains of L. monocytogenes from chicken meat produced in Mato Grosso, confirming that these strains are sensitive to ampicillin and erythromycin.