Prevalence and antibiotic susceptibility of Streptococcus pyogenes isolated from pyoderma in a tertiary care hospital, Hyderabad, South India

Abstract

Pyoderma is a common acute superficial bacterial skin infection which is highly contagious. In the great majority of cases, pyoderma is caused by , , or both. The present study was carried out to determine the prevalence and antibiotic susceptibility of isolated from pyoderma in Dr. VRK Women’s Teaching hospital. Swabs or pus samples were collected from 250 patients attending Dermatology, outpatient department (OPD) of Dr. VRK Women’s Teaching hospital. Samples were inoculated onto 5% sheep blood agar plates and incubated for 24 h at 37°C in a candle jar. BHS isolates were phenotypically identified by standard microbiological techniques, all the isolates presumptively identified as BHS were tested for Bacitracin susceptibility. Presumptive identification of a strain as a Group A Streptococcus (GAS) was also made by PYRase test. Presumptively identified GAS isolates were serogrouped by Lancefield grouping using a commercially available latex agglutination test. isolates were subjected to antimicrobial susceptibility testing by Kirby-Bauer disc diffusion method. BHS were isolated from 30% of samples. Prevalence of BHS was more among 0-10 years age group (38%). BHS were isolated more frequently from males (38.8%). were isolated from 52 (20.8%) samples. All 52 isolates were found to be susceptible to Penicillin G, amoxicillin, ceftriaxone, azithromycin and vancomycin. Erythromycin and clindamycin showed good activity with sensitivity rates of 92.3% & 96.1%, respectively. Resistance to tetracycline (59.6%) and chloramphenicol (23.1%) was commonly seen in . This study reports the prevalence and antibiotic susceptibility of isolated from pyoderma in Dr. VRK Women’s Teaching hospital. Results of this study suggests the peak incidence of pyoderma in children aged 0 to 10 years and male preponderance. Our study also reports high prevalence of tetracycline and chloramphenicol resistance in .