Epidemiology, Clinical Profile and Treatment Outcomes of Bacterial and Fungal Keratitis

Abstract

Purpose: The purpose of the study is to determine the microbiological aetiology, epidemiological factors, and clinical profile and treatment outcomes of infective keratitis in Ophthalmology department, Minia University. EgyptMethods:Prospective, non-randomized, observational clinical series of cases, including 150 patients with mean age 30 (range 12 to 85 years), 90 patients (60 %) were males and 60 (40%) were females, clinically diagnosed as infective corneal ulcer, attending the Ophthalmology Department – Faculty of Medicine. Minia University, Minia, Egypt. From 2018 to 2020.Detailed history taking and all clinical findings were collected. Corneal scrapings were obtained from patients and subjected to staining and culture for bacterial and fungal pathogens; Bacterial and fungal growth were identified by standard laboratory procedures.Results:Corneal trauma by a vegetative matter was the commesnest risk factor associated with infective keratitis in 92 cases (61.3%). Smear and Culture was positive in 83 cases (58.4%) of 142 corneal scrapings obtained, of which 60 cases were fungal (72.3%), 21 cases were bacterial (25.3%) and 2 cases were mixed bacterial and fungal (2.4%), Aspergillus species was the commonest fungal species isolated in fungal keratitis. 142 cases (94.67 %) healed completely with scar. Only 6 cases (4%) required evisceration due to aggressive presentation from the start and keratoplasty was performed for 2 cases (1.33%).Conclusions:Fungal keratitis was the commonest type in cases attending to our department. Adequate diagnosis, management and follow up helped in achieving high successful curative outcomes. Clinical Trials.gov ID: NCT04894630. Time of registration 1 December 2018

The approach to diagnosis and management of corneal ulcers

“…Except for organisms like gonococcus, which can penetrate an intact epithelium to generate ulcers, bacterial corneal ulcers are caused by bacteria penetrating the ocular epithelial barrier after a breach (Mabrouk et al, 2022). The epithelium is susceptible to corneal infection due to corneal edema, extended contact lens wear, dry eyes, and trauma.…”

“…Tears and limbal veins carry inflammatory cells to the corneal breach site, producing cytokines and interleukins that cause the cornea to invade gradually and the ulcer to enlarge (Mabrouk et al, 2022). The organism undergoes phagocytosis, releasing free radicals and proteolytic enzymes that cause necrosis and sloughing of the stroma, Bowman's membrane, and epithelium.…”

“…Fungi are classified as yeast, filamentous septated, pigmented and non-pigmented, and filamentous without septae (Mabrouk et al, 2022). In temperate countries, yeast fungi like candida are widespread, but filamentous fungi like Aspergillus and Fusarium are more prevalent in tropical regions (Wuletaw et al, 2021).…”

“…A host inflammatory response is triggered by the invasion of fungal infections, which can also enter the cornea following an epithelial rupture, trauma, or a foreign body in the form of vegetative material or soil particles. In comparison to bacteria, the inflammatory response is slower and less intense (Mabrouk et al, 2022). In order to penetrate deeper into the stroma and break through Descemet's membrane, fungi release proteolytic enzymes, fungal antigens, and toxins.…”