Demographical and etiological diagnosis of infective corneal ulcer in a tertiary care center in West Bengal: A cross-sectional study

Abstract

Purpose: The purpose was to study the demographical factors and microbial etiology associated with infective keratitis in a tertiary care center in West Bengal. Materials and Methods: In this cross-sectional study, 142 patients with suspected microbial keratitis were enrolled from June 2019 to May 2020. After taking the history and diagnosing the infective ulcer clinically, the corneal scrapings and cultures were evaluated. The smears were fixed with Gram stain and 10% potassium hydroxide wet preparation. The scrapped material was inoculated in blood agar and Sabouraud dextrose agar for culture. Results: Ocular trauma was the most common predisposing factor in 94 (70.6%) corneal ulcers (P < 0.0001). The most common etiologic agent causing corneal injury was wooden object (38.3%). Microbial etiology was established in 76 (53.52%) corneal scrapings. Out of the total culture-positive cases, 45 patients (31.7%) had pure fungal infections, 25 patients (17.6%) had pure bacterial infections, and 6 patients (4.2%) reported mixed infections. Among the fungal pathogens, Aspergillus species was the most common fungal isolate (29 cases, 56.8%), followed by Fusarium species (17 cases, 33.3%) and Candida species (5 cases, 9.8%). The most common bacterial isolate was Staphylococcus aureus (16 cases, 51.6%), followed by Pneumococcus species (7 cases, 22.5%). Conclusion: Trauma with wooden material was the most common predisposing factor for infective keratitis. Fungal ulcers predominated in the study findings. Aspergillus species and S. aureus were the most common fungal and bacterial isolates, respectively. Regional variations exist in the microbial etiology of infective keratitis.