An Initial Study on Normal Commensel Flora of Throat

Abstract

Introduction: The normal throat flora of humans is complex and consists of several species of bacteria. Materials &Methods: The study aimed at finding out the normal commensel flora of throat of healthy individual in a tertiary care hospital with 157 selected individuals of different ages and both sexes over a period of three months (January 2015 to March2015). Diagnosed cases of immunocompromisation were excluded from the study. Aseptically collected throat swabs were processed for microbiological workup as per standard protocols. Speciation and antimicrobial susceptibility testing of the isolates were done by VITEK-2 Advanced Expert System. Data were analyzed as per standard statistical methods. Results: Amongst study population, Staphylococcus aureus was isolated in 71 cases (45.22%), viridans group of Streptococcus (Streptococcus mitis)was isolated from 93 cases (59.23%)and Diphtheroids were isolated in 29 cases (18.47%). Moraxella sppwere isolated in 17 cases(10.82%). Streptococcus pneumoniae was isolated in 13 cases (0.08%) and Candida albicanswas isolated in 9 cases(0.057%). Polymicrobial isolations were associated in 139 cases (88.53%). All of the Streptococcus isolates were sensitive to Penicillin and Erythromycin. All isolated Staphylococcus aureus were sensitive to Vancomycin and Linezolid. Amongst 71 isolated Staphylococcus aureus, 19 were Methicillin resistant (26.76%). Candida isolates were sensitive to Fluconazole and Itraconazole. Candida albicans was isolated from study group belonging to below 10 years and above 60 years. Moraxella spp. was isolated from the age group of 21years to 40 years. ViridansStreptococcus and Mthicillin Resistant Staphylococcus aureus were isolated from the study population aged ≥10 years. Conclusion: Viridans group of Streptococcus is the leading microbe to form the commensal flora of throat specially after 10 years.