Einstein International Journal Organization(EIJO)

Abstract

Background: Microbial keratitis is a potentially sight-threatening corneal infection and a major cause of preventable corneal blindness in developing countries, particularly in tropical and agrarian regions of India. Early identification of clinical patterns and etiological agents is essential for timely management and improved visual outcomes.

Objectives: To evaluate the demographic characteristics, predisposing factors, clinical presentation, microbiological spectrum, complications, and predictors of visual outcome in patients with microbial keratitis presenting to a tertiary care hospital in Central India.

Methods: This hospital-based prospective observational study was conducted over 12 months (July 2024–June 2025) in the Department of Ophthalmology at a tertiary care teaching hospital in Central India. A total of 240 patients with clinically diagnosed microbial keratitis were enrolled. Detailed history and comprehensive ophthalmic examination were performed. Corneal scrapings were subjected to Gram staining, KOH mount, and culture on standard media. Antibiotic susceptibility testing was conducted using the Kirby–Bauer disc diffusion method as per CLSI 2023 guidelines. Patients were followed for 3 months. Statistical analysis was performed using SPSS version 26.0, with p < 0.05 considered statistically significant.

Results: The mean age of patients was 42.6 ± 15.8 years, with the highest incidence in the 21–40 years age group (40%). Males constituted 64.17% of cases. Ocular trauma was the most common predisposing factor (49.17%), particularly vegetative matter injury (35%). Bacterial keratitis (56.67%) was more prevalent than fungal keratitis (34.17%). Medium-sized ulcers (2–5 mm) were most common (50.83%), while 30% presented with large ulcers (>5 mm). Hypopyon was observed in 40.83% of cases. At 3 months, 46.67% achieved BCVA ≥6/18, whereas 22.5% had BCVA <6/60. Multivariate logistic regression identified large ulcer size (Adjusted OR 4.76), delayed presentation >7 days (Adjusted OR 3.92), fungal etiology (Adjusted OR 2.48), and presence of hypopyon (Adjusted OR 2.15) as independent predictors of poor visual outcome (p < 0.05).

Conclusion: Microbial keratitis predominantly affects working-age males and is strongly associated with ocular trauma in this region. Although bacterial keratitis was more common, fungal keratitis was associated with poorer outcomes. Large ulcer size, delayed presentation, fungal etiology, and hypopyon significantly predicted visual impairment. Early diagnosis, prompt microbiological evaluation, and timely targeted therapy are crucial to reducing corneal blindness.

Keywords: Microbial Keratitis, Corneal Ulcer, Fungal Keratitis, Bacterial Keratitis, Ocular Trauma, Visual Outcome, Hypopyon, Tertiary Care Hospital, Central India.

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