Occurrence of the vanA gene in Staphylococcus epidermidis from nasopharyngeal secretion of Health-Care Workers, Recife, Brazil

Abstract INTRODUCTION: The increasing reports of vancomycin-resistant Staphylococcus strains (VRS) haves caused concern worldwide, from the laboratory detection to patient management. This study aimed to identify the occurrence of VRS strains among healthcare professionals from a university hospital. METHODS: A total of 102 Staphylococcus sp. isolates from healthcare professionals, obtained in a previous study were evaluated according to standard techniques for VRS detection. RESULTS: After screening inoculation of plates containing 6µg/ml of vancomycin, 19 resistant isolates were identified. The susceptibility profile to other antimicrobials revealed 18 multidrug resistant isolates. The minimum inhibitory concentration (MIC) was determined by E-test and broth microdilution. According to E-tests, of 19 isolates grown in BHI-V6, four isolates presented MIC ≥ 128 µg/ml, seven with MIC ranging from 4 to 8 µg/ml, and eight with MIC ≤ 2µg/ml. By broth microdilution, 14 isolates presented MIC ≤ 2 µg/ml and five with MIC ≥ 16µg/ml. The presence of the gene vanA was determined by PCR in the five resistant isolates, and this gene was detected in one of the strains. Furthermore, among the 19 strains, the gene mecA was found in 13 (39,4%) isolates, including the strain carrying the gene vanA. CONCLUSIONS: Based on these results, we highlight the presence of one strain carrying both vanA and the mecA genes, as well as multidrug-resistant strains colonizing healthcare professionals, and their importance as potential vectors to spread strains carrying resistance genes in the hospital environment