Resumo

Enterococcus spp are recognized by their pathogenic potential in humans, mainly by high mortality rates in nosocomial infections. A factor that contributes to its pathogenicity is extrinsic and intrinsic resistance to antibiotics. The aim of this study was to evaluate the antibiotic resistant of Enterococcus spp isolated from food. Bacterial used in this study are isolated from 19 samples of “Minas frescal” cheese of trade from Londrina, PR. Cheese samples (25 g) were homogenized in 250 ml of peptone water for 3 min. The suspensions (0.1 ml) were directly spread onto Enterococcus spp selection KEAA (kanamicyn esculin azida agar). The bacteria isolated were identified by biochemical tests and confirmed by molecular technique of Polymerase Chain Reaction (PCR) with specific primers. Antimicrobial susceptibility testing was determined using the disk diffusion method on Mueller-Hinton agar as established by the Clinical and Laboratory Standards Institute (CLSI). The following antimicrobial agents were used in this study: nalidixic acid (30μg), vancomycin (30μg), imipenem (10μg), erythromycin (15 μg), tetracycline (30 μg); amikacin (30μg), norfloxacin (10μg), cephalothin (30 μg), ciprofloxacin (5 μg), amoxicillin and clavulonic acid (10-20μg), chloramphenicol (30 μg) and ampicillin (10μg). Were obtained 36 isolates of Enterococcus sp:E. faecium(n = 21),E. faecalis (n = 10), E. casseliflavus (n = 4) and E. gallinarum (n = 1). Some samples of cheese (52%) showed more than one species of Enterococcus. The highest rate of antimicrobial resistance was to nalidixic acid (n = 19), tetracycline (n = 11), vancomycin (n = 7) and erythromycin (n = 7). The species most frequently expressed resistance was E.faecium followed by E.faecalis. In conclusion, the isolation of Enterococcus spp in food is an indicator of contamination that might suggest problems related to sanitary conditions of its acquisition, storage or transport, and also isolates resistant to antimicrobials, clinic of choice, is of concern because they can transmit resistant for strains of the natural microbiota of humans.