Abstract Introduction: Skin infections are one of the commonest conditions encountered in dermatological practice. These infections are commonly caused by Staphylococcus. aureus and Streptococcus. pyogens. Of late there is a significant change in the pattern of organisms causing pyodermas and their antibiotic sensitivities due to indiscriminate use of topical and systemic antibiotics. The present study was undertaken to find the causative organisms and their pattern of antibiotic susceptibility. Objective: The objective was to isolate and identify various microorganisms and study the antibiotic sensitivity patterns in primary and secondary pyodermas. Methods: 100 consecutive clinically diagnosed and untreated cases of primary and secondary pyoderma were studied over a period of 1 year. All clinically diagnosed cases of pyoderma with positive pus culture report, irrespective of age and sex were included. Cases with history of using topical or systemic antibiotic in the past 2 weeks were excluded. Primary inoculation of the swab was done on MacConkey Agar Plate (M.A), Nutrient Agar Plate (N.A) and Blood Agar Plate (B.A). These samples were incubated aerobically at 37 degree C for 24 hours. Plates showing no growth during the first next 24 hours were further incubated for 24 hours. Various subcultures and standard biochemical tests were performed for identification of organisms. Sensitivity of the organisms to antibiotics was tested on Muller Hinton agar by Kirby- Bauer disc diffusion method. For analysis of data, Chi-Square test was applied. Results: Higher incidence of primary pyodermas were seen in all age groups compared to secondary pyodermas. Lower extremities were involved frequently. In 93 (93%) patients gram-positive organisms, while in 6(6%) patients gram-negative organisms were isolated. Staph. aureus was isolated from 84 (84%) samples followed by coagulase negative staphylococcus (5, 5%) E.coli (4;4%), Strept. Haemolyticus (2; 2%), strept. Non-haemolyticus (3; 3%), pseudomonas (1;1%) enterobacter (1;1%). Conclusion: This study yielded some useful epidemiological andclinico-bacterilogical data that might assist clinicians to choose suitable antibiotics for pyodermas, especially in absence of culture and sensitivity report.

Keywords: pyoderma