Multidrug Resistance and Phage Pattern of Staphylococcus Aureus in Pyoderma Cases

Background: Pyoderma is common in India and other tropical countries. Staphylococcus aureus is the commonest causative agent of pyoderma. Aims and Objectives: To know the antibiotic susceptibility and bacteriophage pattern of Staphylococcus aureus isolated from pyoderma infection. Materials and Methods: One hundred clinically diagnosed pyoderma cases were investigated bacteriologically. A total of 59 isolates of S. aureus were subjected to antibiotic susceptibility testing by Kirby Bauer s disk diffusion method and phage typing by routine test dilution X 100 bacteriophages. Results: Most of the strains were resistant to penicillin, ampicillin and were susceptible to gentamicin, streptomycin and erythromycin. Multidrug resistance was also high among these strains. Regarding the phage types, Phage type 52 (15 strains), 96 (8 strains) and 71(16 strains) were predominant among the typed strains (55.95%) of S. aureus. The most common group was mixed phage group (17%) followed by phage group I (13.55%). Conclusion: Knowledge of antibiotic susceptibility pattern is essential to give proper antibiotic therapy and avoid unnecessary medication with non-effective drugs, which may increase resistance. Gentamicin, streptomycin and erythromycin are the drugs of choice in that order. Association of phage typing and antibiotic sensitivity of S. aureus showed the predominance of phage group III with greater frequency of penicillin resistance