Profile of Microbial Isolates in Ophthalmic Infections and Antibiotic Susceptibility of the Bacterial Isolates: A Study in an Eye Care Hospital, Bangalore

Abstract

Ocular infections are common and vary from self-limiting to sight-threatening. All the structures of the eye can be infected by various microbes.The present study was undertaken to determine the prevalence of bacterial and fungal infections of the eye and also to assess the antibiotic susceptibility pattern of bacterial isolates at an eye care hospital in Bangalore, India. Two hundred thirty five samples were received from infections of the eye-conjunctivitis including dacrocystis, corneal ulcers, endophthalmitis and post-traumatic infections. Culture, Gram's stain and potassium hydroxide (KOH) mount was done for allclinical specimens. Giemsa staining was done occasionally as required. Antibiotic susceptibility testing was performed for bacterial growth. Out of 235 samples processed, 81(34.5%) yielded bacterial growth and 32 (13.6%) yielded fungal growth. One corneal scraping showed the presence of Acanthamoeba by microscopy. Predominant bacterial isolates were-Staphylococcus species 36 (39.9%), Pseudomonas species 20 (22.2%) and Escherichia coli 12 (13.3%). Among 25 fungal isolates, Aspergillus flavus 11(44%) and Fusarium 8 (32%) predominated. Bacterial strains were susceptible to gatifloxacin (86.4%), tetracycline (65.4%), chlorampenicol (69.1%) and least sensitive to the beta- lactam group like amoxicillin (23.5%). Conjunctival specimens yielded mainly bacterial growth with Staphylococcus species being the predominant isolate followed by Pseudomonas species. Maximum fungal isolates were from corneal scrapings with Aspergillus flavus and Fusarium being predominant. Majority of the bacteria were susceptible to gatifloxacin.