Abstract

Ocular infections are widespread and they exert heavy burden on eye health. Virtually, any eye component can be infected by a diversity of bacteria. The present study was performed to determine the prevalence of external ocular bacterial infections and to find out antibiotic susceptibility pattern of bacterial isolates at eye care hospitals in Khartoum, Sudan. Two hundred and four corneal scrape and drained pus materials were received from infected eyes with clinical diagnoses of bacterial conjunctivitis, keratoconjunctivitis, keratitis, blepharo-conjunctivitis, blepharitis, dacryo-cystitis and eye abscess. Culture, microscopy with Gram’s stain of both samples, bacterial colonies and biochemical tests were carried out. Antibiotic susceptibility analysis using Kirby–Bauer disc diffusion test and standard table of antibiotic susceptibility was performed. Out of 204 samples processed, 130 (63.7%) yielded bacterial growth. The most prevalent bacterial eye infection was conjunctivitis (59.2%). Of all the isolates, 75 (57.7%) were Gram’s positive and 55 (42.3%) were Gram’s negative. Coagulase positive Staphylococcus aureus were the most prevalent, 39 (30%) followed by Streptococcus pneumonia 31 (23.8%), Haemophilus influenzae 22 (16.9%), Pseudomonas aeruginosa 13 (10%) and Neisseria gonorrheae 10 (7.7%). Gram positive bacteria were highly sensitive to vancomycin (95%), followed by chloramphenicol and ciprofloxacin (91%) and ceftriaxone (84%), while the majority were resistant to penicillin (72%). Gram-negative organisms were highly susceptible to amikacin (92.7%) followed by ceftriaxone (87.3%) and ciprofloxacin (78.2%). Major resistance was towards cotrimoxazole (82%) and ampicillin (73%).

Key words: External ocular bacterial infections, bacterial isolate, antibiotic susceptibility, normal flora, pathogenic bacteria.