Investigation of four diagnostic methods to identify infectious ulcerative keratitis in horses in Colorado, USA

Le résumé fourni par la source

Summary Background Ulcerative keratitis in equine patients can result in keratomalacia and perforation. Prompt and accurate diagnostics are necessary for appropriate therapy and a favourable outcome. Objective To determine the diagnostic utility (specificity and speed) of four diagnostic methods for infectious ulcerative keratitis in the horse. Study design Prospective methodology pilot study. Methods Ten client‐owned horses presented to Colorado State University's veterinary ophthalmology service for suspected infectious ulcerative keratitis from June 2021 to July 2022. For all horses, a complete ophthalmic examination was done along with the collection of appropriate samples for corneal cytology, culture (aerobic bacterial and fungal culture), next‐generation sequencing (NGS) and quantitative polymerase chain reaction (qPCR) analysis for the detection of Aspergillus fumigatus , Fusarium sp. and Candida albicans . A mixed effects statistical model was used to compare the four methods, and p ‐values ≤0.05 were statistically significant. Results Sixty per cent of horses ( n = 6) had infectious organisms noted on cytology, 50% ( n = 5) had positive growth on aerobic bacterial culture, 10% ( n = 1) had positive growth on fungal culture ( Penicillium sp.), 30% ( n = 3) had positive identification of infectious organisms on NGS, and all were negative for fungal qPCR. There was not significant evidence to suggest that the odds of a positive test were different among the methods ( p = 0.276). There was evidence that the average time to receive results for fungal culture is higher than the other diagnostics ( p < 0.001). There was not sufficient evidence that the average time to receive results differed between aerobic culture and cytology ( p = 0.622) or aerobic culture and NGS ( p = 0.140). Main limitations Small sample size and Colorado's low prevalence of fungal disease contributed to low statistical power. Conclusions Based on the results of the current study, there was no significant evidence to suggest that the odds of a positive test were higher for any diagnostic methods tested.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.