Antibiotic Susceptibility Pattern and Bacterial Spectrum Among Patients with External Eye Infections at Menelik II Referral Hospital in Addis Ababa, Ethiopia

Abstract

Background: Eye infections can cause loss or impairment of visual function and can lead to severe impairment. Bacteria are the most common pathogens that affect the structure of the eye. As a result, quick identification of the causative agents and testing of their medication susceptibility are essential for effective treatment of eye infections. This study was intended for determining the extent of bacterial isolates from external eye infections (EEIs) and their susceptibility to antibiotics. Methods: A facility-based cross-sectional study was conducted among patients attending Menelik II Referral Hospital. The study comprised patients who had EEIs verified. EEI samples were collected using sterile methods. Bacterial isolates were identified using gram stain, colony morphology, and biochemical tests. The Kirby-Bauer disk diffusion technique was used to conduct a drug susceptibility test. Results: Totally, 323 participants were recruited for this study and 184 bacterial isolates were obtained from 175 (54.5%) participants. The main clinical diagnosis was blepharitis 122 (37.8%), followed by conjunctivitis 73 (22.6%) and keratitis 57 (17.6%). The gram-positive isolates were 171 (92.9%). CoNS with a frequency of 76 (41.3%) was the most common bacterial isolates, followed by S. aureus 67 (36.4%), Viridans streptococcus 16 (8.7%), and Klebsiella species 6(3.3%). Gram-positive isolates were sensitive to tobramycin, gentamicin, chloramphenicol, vancomycin, and ceftriaxone. In contrast, 94.0% of these gram-positive isolates showed resistance to penicillin. Multidrug resistance (MDR) was observed in both gram-positive and negative bacteria at rates of 123 (72%) and 12 (92.1%), respectively. The overall MDR rate among the isolates was 135 (73.4%). Conclusion: In this study, blepharitis was the major EEI, followed by conjunctivitis. The predominant bacterial species isolated from EEIs were CoNS, followed by S. aureus. More than half of the isolates were drug-resistant, with a large number being multidrug-resistant, highlighting the necessity for continued and coordinated surveillance to hunt for infections that are known to be resistant.