Ocular bacterial flora and antibiotic sensitivity among Filipino patients undergoing routine cataract surgery

Abstract

Objective: This study determined the most common normal lid-margin and conjunctival bacterial flora, antibiotic sensitivity, and resistance patterns in eyes of Filipinos scheduled for routine cataract surgery at a tertiary government hospital.

Methods: Lid-margin and conjunctival swab specimens were collected from patients scheduled to undergo routine cataract-extraction surgery at the Department of Ophthalmology and Visual Sciences of the University of the Philippines– Philippine General Hospital. The specimens were cultured using standard technique and those with bacterial growth were tested for antibiotic sensitivity and resistance using the disc-diffusion method.

Results: Sixty eyes of 30 patients were sampled, 17 females (57%) and 13 males (43%), with a mean age of 61.4  12.5 years (range, 37 to 84). Of the 30 patients swabbed, 27 (90%) were culture positive. The most common organism identified was Staphylococcus epidermidis (24/27, 89%). Bacillus sp. was identified in 12 (44%) patients. Staphylococcus aureus was identified in 3 (12%) patients. Results of antibiotic sensitivity testing revealed that 85% or more of the coagulase-negative staphylococcus isolates were sensitive to moxifloxacin, gatifloxacin, ciprofloxacin, vancomycin, gentamycin, tobramycin, and chloramphenicol.

Conclusions: Staphylococcus epidermidis was the most frequently isolated organism in the eyelid margin and conjunctiva of patients for routine cataract surgery. The isolates showed high sensitivity to commonly prescribed topical antibiotic preparations.