Background: A corneal ulcer or keratitis is an open sore on the cornea. The cornea covers the iris and the round pupil much like a watch crystal covers the face of a watch. A corneal ulcer usually results from an eye infection, but severe dry eye or other eye disorders can cause it. Corneal ulcer is a major cause of ocular blindness and visual disability in different developing countries in Middle East, Africa and Asia, ranking only second to cataract. This is an endeavour to study about the microbiological figure and prevalence of infectious keratitis in a tertiary eye care hospital of Eastern India, and to test for the in vitro antimicrobial resistance of the bacterial isolates.

Methods: A total of 348 patients who visited a tertiary eye care hospital in Eastern India, with infected corneal ulcer were enlisted in this study. Their risk factors and socio‑demographic data were documented. Corneal scrapings were assembled from the margin of the ulcer and sent for routine microbiological examination which included Gram stain and KOH mount. Culture was obtained from MacConkey agar, blood agar, chocolate agar and Sabouraud’s dextrose (SDA) agar in multiple C shaped streaks. After overnight incubation, bacterial culture was proceeded by standard biochemical tests and antimicrobial sensitivity as stated in the clinical and laboratory standards institute (CLSI) guidelines. Inoculated SDA was observed everyday for up to 10 days and the growth was identified by its colony morphology, pigment production and lacto‑phenol cotton blue mount examination.

Results: Of 348 patients, a microbial etiology was entrenched in 132 cases (37.5%). Of these, 84 (63.63%) were male. The 41‑60 years age range was the most afflicted group. Of 132 positive cases, 58 (43.93%) were bacterial, 67 (50.75%) were fungal and 7 (5.30%) patients showed mixed variety. The most common isolated fungus was Fusarium which was detected in 44 (33.33%) cases, succeeded by Aspergillus spp in 13 (9.84%) patients. Staphylococcus aureus was the most prevailing isolated bacteria. All Gram positive cocci were susceptible to Vancomycin followed by Gatifloxacin, while all Gram negative bacilli were susceptible to Gatifloxacin.

Conclusion: These findings demonstrated the current trend in the microbiological etiology of patients with corneal ulcer in Eastern India, which has a significant public health involvement for the treatment in conjunction with prevention of corneal ulceration in developing world. 

Keywords: Corneal Ulcer; Microbiological figure; Antibiotic Susceptibility.

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Raktima Baksi (Mandal)

RMO-CT (Tutor), Dept. of Ophthalmology, Rampurhat Government Medical College, Birbhum