Frequency and antimicrobial resistance in Staphylococcus

The objective of the present investigation was to establish the frequency of isolation of the different species of staphylococci and to determine the antimicrobial resistance of the isolated strains. A retrospective study was carried out in isolated strains at the Bacteriological Reference Center of the Autonomous Service of the University Hospital of Maracaibo during the period January 2011 to December 2015. A percentage of isolation was obtained for S. aureus of 61.36% and 38, 64% for coagulase negative, showing a higher frequency of isolation in the hospitalization area for both groups of microorganisms. Skin and soft tissue samples represented the main sources of isolation for S. aureus; while for the coagulase negative group, they were blood samples. All strains were sensitive to glycopeptides. Resistance for β-lactams was accentuated for both bacterial groups, showing variability for macrolides and lincosamides and for the remaining antibiotics tested, low percentages of resistance were found. The results show that S. aureus is the most frequent species of the genus; followed by S. epidermidis and S. haemolyticus, among coagulase negative. Both groups of microorganism express phenotypes of resistance to penicillin and erythromycin, sensitivity to vancomycin and teicoplanin and variable susceptibility to the rest of evaluated antibiotics.