Successful treatment of localised ocular sporotrichosis caused by itraconazole-resistant Sporothrix schenckii complex in a cat.

Abstract

Case summary: A 2-year-old, indoor domestic shorthair cat presented with a 3-week history of a progressively growing subconjunctival nodule on the right upper eyelid. Fine-needle aspiration was performed and the sample was submitted for cytological examination. The nodule became an ulceration near the lateral canthus within 1 week after application of ofloxacin-prednisolone eye drops. Yeasts of Sporothrix species were detected and treatment was initiated with itraconazole. As the ulcerated nodule continued to progress, the regimen was modified to terbinafine combined with high-dose itraconazole. Sporothrix schenckii complex was diagnosed from fungal culture, and the antifungal testing reported itraconazole resistance. However, the ulceration showed responsiveness to the combined treatment by day 43. Finally, the ulcerated eyelid was healed after 5 months of antifungal therapy. No recurrence of ocular sporotrichosis was detected at the termination of antifungal medications after 2 years.

Relevance and novel information: Feline sporotrichosis is commonly reported in tropical countries; however, localised nodules and eyelid ulcerations due to S schenckii infection are generally uncommon. To the authors' knowledge, this is the first report of localised ocular sporotrichosis in a cat in Thailand. Furthermore, although itraconazole resistance was detected in the fungal culture, the combination of high-dose itraconazole and terbinafine proved effective in treating a cat infected with a non-wild-type S schenckii complex in the current study.