Conjunctival Bacterial Antibiotic Sensitivity Pattern in Patients Undergoing Cataract Surgery at the National Eye Centre, Kaduna, Nigeria

Background: Bacterial contamination from conjunctiva of surgical eye patients may lead to infective endophthalmitis and identification of conjunctival isolates and their antibiotic sensitivity would help in planning appropriate prophylactic interventions. The objective was to determine the predominant conjunctiva bacterial flora in patients scheduled for cataract surgery and their antibiotic sensitivity pattern. Materials and methods: The study comprised of 275 consecutive adult patients who underwent cataract surgery from January to April 2017 and met the inclusion criteria. The participants' socio-demographic characteristics, social, and medical history were obtained through interviewer-administered Questionnaire. Conjunctival swabs were collected from patients prior to cataract surgery and used to inoculate blood agar and chocolate agar plates and then incubated at 37°C for 18-24 hours. Bacterial identification was then carried out using standard. methods. Susceptibility testing was done on Mueller Hinton agar based on modified Kirby Bauer methods using the following drugs; Chloramphenicol, Ciprofloxacin, Ofloxacin, Levofloxacin, Imipenem, Cefuroxime, Ceftriaxone, Ceftazidime, Amikacin, Gentamicin, Tetracycline and Penicillin. Epi Info 7 software was used for univariate and bivariate data analysis as appropriate. Results: Bacterial growth was seen in 118 (42.9%) of the patients. The bacteria identified were: Staphylococcus epidermidis (48.3%); Staphylococcus aureus (44%); Gram positive bacilli (6%) and Streptococcus species (1.7%). The isolates were susceptible to Imipenem, Cefuroxime, Gentamicin, Chloramphenicol, Amikacin and Levofloxacin. Resistance to Tetracycline and Penicillin was also recorded. A statistically significant relationship was found between age and culture status (p = 0.0192). Conclusion: The predominant bacteria on the conjunctival sac were Staphylococcus epidermidis and Staphylococcus aureus, which were sensitive to some commonly perioperative antibiotics like chloramphenicol and gentamicin. Keywords: Cataract surgery; Conjunctival flora; Antibiotic sensitivity