Normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity, in patients undergoing cataract surgery at Phramongkutklao Hospital

OBJECTIVE This study aimed to evaluate the normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity. DESIGN This was a prospective cross-sectional study. PATIENTS AND METHODS A prospective study was conducted on 120 patients who underwent cataract surgery at the Phramongkutklao Hospital from September 2014 to October 2014. Conjunctival and lid margin swabs were obtained from patients before they underwent cataract surgery. These swabs were used to inoculate blood agar and chocolate agar plates for culturing. After growth of the normal flora, the antibiotic sensitivity method using tobramycin, moxifloxacin, levofloxacin, and cefazolin was applied. MAIN OUTCOME MEASURES Normal flora of conjunctiva and lid margin, along with its antibiotic sensitivity, from patients who underwent cataract surgery was assessed. RESULTS A total of 120 eyes were included in this study, and bacterial isolation rates were identified. Five bacteria from the lid margin were cultured, namely, coagulase-negative staphylococcus (58.33%), Streptococcus spp. (2.5%), Corynebacterium (1.67%), Micrococcus spp. (1.67%), and Staphylococcus aureus (0.83%). Two bacteria from the conjunctiva were cultured, namely, coagulase-negative staphylococcus (30%) and Streptococcus spp. (0.83%). Results of antibiotic sensitivity test showed that all isolated bacteria are sensitive to cefazolin 100%, tobramycin 98.67%, levofloxacin 100%, and moxifloxacin 100%. CONCLUSION Coagulase-negative staphylococci are the most common bacteria isolated from conjunctiva and lid margin.