Non-gonococcal bacterial agents of conjunctivitis and their antibiotic susceptibility patterns in Ilorin, Nigeria.

Periodic bacteriological surveillance of purulent ocular discharge is a necessity. To determine the prevalent bacterial agents of purulent conjunctivitis and their antibiotic susceptibility patterns at the University of Ilorin Teaching Hospital (UITH), Ilorin, Nigeria. All bacterial isolates obtained during routine processing of conjunctival swab specimens were studied at the Department of Microbiology UITH between January and December 2004. The isolates were obtained after inoculation of the specimens onto blood, chocolate and MacConkey agar plates, incubated at 37 degrees C for 18-24hours under aerobic conditions except for chocolate agar plates which were kept in candle extinction jar. The isolates were identified using a combination of colony morphology, biochemical and/or serological tests as applicable. Antibiotic sensitivity testing was performed using the modified Kirby Bauer method. One hundred and four conjunctival swabs from 104 patients were analysed and 72 were bacteriologically positive, giving prevalence rate of 69.2%. The positive samples were from 42 males and 30 females with M:F ratio of 1.4:1. The age range was from 5 hours of life to 80 years. Well over half (61.1%) of the swabs were from neonatal age group. The isolated organisms included Staphylococcus aureus 43.1%, Klebsiella pneumoniae 22.2%, Pseudomonas aeruginosa 3.9%, Streptococcus pneumoniae 11.1%, and Escherichia coli 9.7%. Most of the isolates were sensitive to fluoroquinolones while erythromycin has the least bacterial coverage. The most common bacterial agent of purulent conjunctivitis in Ilorin is Staphylococcus aureus and fluoroquinolones have the best coverage for common bacterial agents of purulent conjunctivitis.