Equine keratomycosis in Switzerland: a retrospective evaluation of 35 horses (January 2000-August 2011).

REASON FOR PERFORMING STUDY

Keratomycosis is a severe disease in horses. Geographical differences in fungi causing keratomycosis and susceptibility of the organisms to antifungal drugs exist but few previous publications on this disease originate from Europe.

OBJECTIVE

To retrospectively compare the clinical data of 36 eyes with keratomycosis, diagnosed in 35 horses between January 2000 and August 2011 at the Vetsuisse Faculty of Switzerland. Case history, season, prior treatment, clinical appearance, surgical and medical treatment, treatment duration, and globe survival were evaluated.

STUDY DESIGN

Retrospective case series.

METHODS

Medical records of horses with a definitive cytological or histological diagnosis of keratomycosis were reviewed.

RESULTS

Thirty-one of 36 eyes (86.1%) presented with ulcerative keratitis, 2/36 (5.55%) had diffuse corneal infiltration, 2/36 (5.55%) had superficial punctate keratitis and 1/36 (2.8%) had a fluorescein-negative fungal plaque. Two of 6 fungal cultures produced Aspergillus spp. Thirty eyes received medical and surgical treatment, while 3 eyes were treated medically only. In 3 horses the globe was removed at the time of first presentation. Sex, age, prior treatment with antimicrobials or steroids, or type of surgical approach did not significantly influence the outcome. Twenty-three of 36 eyes (63.9%) were at least partially visual, 11/36 eyes (30.5%) were enucleated and 2 horses (2/36 eyes, 5.6%) were subjected to euthanasia. Treatment protocols were compared in the 31 eyes with ulcerative keratitis. In this group, 3/31 globes were immediately enucleated, 16/31 eyes were treated topically with voriconazole or voriconazole/fluconazole and 12/31 with other antifungal drug combinations. The different medication protocols did not significantly affect the outcome.

CONCLUSIONS

There were no significant differences in outcome between different medical treatment protocols or types of surgical approach.

POTENTIAL RELEVANCE

Future studies in central Europe should focus on the identification of fungal pathogens, susceptibility patterns and the efficacy of antifungal drug therapies.