Clinical and Etiological Profile of Mycotic Keratitis from a Tertiary Care Centre in South India

Abstract

BACKGROUND Corneal ulcer is the leading cause of ocular morbidity and monocular blindness worldwide. To effectively prevent blindness in patients with corneal ulcer, a proper understanding of the risk factors predisposing to ulceration, its clinical and microbiological characteristics are essential. Timely identification of aetiological agents causing corneal ulcers and their prompt treatment helps to save the vision. We wanted to detect aetiological agents of corneal ulcer with special references to fungal causes and characterize the fungal aetiological agents to species level. METHODS This is a cross sectional study, conducted in Government Medical college, Kozhikode, between January 2016 and June 2017. All patients who were clinically diagnosed as cases of infectious corneal ulcer in the Ophthalmology department, Government Medical College, Kozhikode were included in the study. Corneal scrapings collected from the infected eye were subjected to microbiological examination and culture. A total of 120 cases were analysed. Each patient was examined with the slit lamp bio microscope after staining with fluorescein. Scrapings from cornea at the site of corneal ulcer were collected by ophthalmologist after a detailed clinical history and examination of the affected eye. The laboratory procedures used in the diagnosis of infectious keratitis were based on direct visualization of organisms by subjecting corneal scrapings to Gram stain and KOH wet mount and inoculation of material on to blood agar and Sabouraud dextrose agar. RESULTS Among the 120 cases, a total of 49 cases were culture positive. Twenty-one [17.5 %] were bacterial, twenty-two [18.34 %] were fungal and six [5.0 %] were poly microbial [bacteria and fungus]. Among the fungal aetiology, fusarium species was most common [32.14 %], followed by aspergillus species - 25.0 %. Trauma was the major risk factor. Diabetes mellitus, exposure keratitis were the other comorbidities / risk factors. CONCLUSIONS This study shows majority of infected corneal ulcers are associated with risk factors and the aetiology are mainly fungi. Microscopy, culture, and clinical correlation helped in adequate management. Thus, prognosis and outcome of corneal ulcers rely on timely identification of their aetiology and prompt treatment. KEY WORDS Corneal ulcer, Fungal Keratitis