Reliability of clinical signs in diagnosis of fungal keratitis

Abstract

Objective: To determine clinical signs predictive of fungal Keratitis (MK) in Uganda.
Methods: We prospectively recruited patients presenting with MK at two main eye units in Southern Uganda between December 2016 and March 2018. We collected information on clinical history and presentation and microbiology. Clinical signs predictive of a positive microbiological diagnosis of fungal keratitis were analyzed in a multi variable logistic regression model.
Results: Three hundred and thirteen individuals were enrolled. Median age was 47 years (range 18-96 years) and 174 (56%) were male. Trauma was reported by 29% and use of traditional eye medicine by 60%. Majority presented with severe infections (median infiltrate size 5.2 mm); 47% were blind in the affected eye (vision <3/60).
Microbiology results were available in 265/313 (84.7%) participants. Overall, most infections were fungal (49%), 10% were bacterial and 4% were mixed (fungal and bacterial). Ninety-seven (37%) of the corneal scrapping samples were negative on both microscopy and culture. Presence of a slough (aOR 3.58, 95% CI [1.60-8.04], p=0.002), a serrated infiltrate margin (aOR 1.58, 95% CI [1.00-2.51], p=0.051), satellite lesions (aOR 2.90, 95% CI [1.65-5.11], p<0.0001) and a hypopyon (aOR 3.24, 95% CI [1.78-5.90], p<0.0001) were associated with a positive microbiology result for fungal keratitis.
Conclusion: This study conducted in a predominantly African population provided clues to support clinicians in making a diagnosis of fungal keratitis in settings where there is no microbiology support.