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Published on: August 11, 2018
Visual Impairment in Fungal Versus Bacterial Corneal Ulcers 4 Years After Successful Antimicrobial Treatment
Namperumalsamy V Prajna1, Muthiah Srinivasan1, Jeena Mascarenhas1
1Department of Cornea and External Diseases, Aravind Eye Care System, Madurai, India.
Purpose:
To compare longitudinal outcomes of visual acuity after fungal corneal ulcers with those of bacterial ulcers.
Design:
Prospective cohort study.
Methods:
This study was conducted in a tertiary eye hospital in South India. The population consisted of 100 of 152 individuals whose fungal or bacterial keratitis had been diagnosed 4 years prior and had been enrolled in 1 of 2 concurrent randomized trials. Causative organisms of infectious keratitis were either bacterial or fungal. Presenting visual acuity consisted of best spectacle corrected visual acuity (BSCVA) and hard contact lens-corrected visual acuity (CLVA).
Results:
Fifty study participants with prior fungal keratitis and 50 with prior bacterial keratitis were enrolled. Four years after treatment for keratitis, participants' presenting vision in the better eye was worse than 20/60 for 12 individuals (24.0%) in the fungal group and 10 individuals (20.0%) in the bacterial group. Median BSCVA in the affected eye at the 4-year visit in the fungal group was similar to that in the bacterial group (Snellen equivalent, 20/32 for each), although vision worse than 20/400 was more common in the fungal ulcer group after spectacle correction (odds ratio [OR] 4.19; 95% confidence interval [CI], 1.11-15.8) and contact lens correction (OR, 5.74; 95% CI, 1.37-24.1).
Conclusions:
In this South Indian population with a previous episode of fungal or bacterial keratitis, correctable bilateral visual impairment was common. Although long-term visual outcomes were, on average, similar between fungal and bacterial ulcers, fungal ulcers were more likely to produce severe visual impairment.
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