Management of bilateral uveitis in aToxoplasma gondii‐seropositive cat with histopathologic evidence of fungal panuveitis

Abstract

A 5-year-old, neutered male Domestic Short-haired cat was referred with a 5-month history of anterior uveitis and cataract in the right eye. Clinical examination confirmed anterior uveitis and immature cataract in the right eye and chorioretinitis in the left eye. Ocular ultrasound showed a retinal detachment in the right eye. Diagnostic testing revealed elevated serum titers for Toxoplasma gondii. Anterior uveitis in the right eye and chorioretinitis in the left eye progressed, resulting in blindness despite a 21-day course of clindamycin and aggressive topical medical management of uveitis. The right eye was enucleated and histopathologic evaluation of the globe revealed panuveitis and multiple organisms morphologically consistent with Histoplasma capsulatum. Systemic treatment with itraconazole was initiated. Vision returned after 3 months of treatment and complete resolution of the retinal hemorrhages with formation of a flat chorioretinal scar was noted after 6 months of therapy. Itraconazole was discontinued 7 months after starting therapy, at which time the funduscopic appearance of the chorioretinal scar had remained static for 1 month. The cat has remained visual without evidence of disease progression for 6 months following discontinuation of itraconazole.

Utility of antigen testing for the diagnosis of ocular histoplasmosis in four cats: a case series and literature review

“…Although immunosuppression due to concurrent feline leukemia virus or feline immunodeficiency virus infection is reported, evidence of retroviral infection was not found in the three cats tested in the present series. 19,20,48,51 In case 2, serial T gondii titers did not change despite this cat improving clinically while receiving clindamycin and antifungal therapy. Thus, it seems likely that fungal infection was the primary agent in this case.…”

“…These cases are similar to a cat from Missouri that had an elevated Toxoplasma species titer but failed to improve clinically on antiprotozoal therapy until an antifungal drug was also initiated. 51…”

Canine and Feline Uveitis

“…Aqueous or vitreous paracentesis may be useful depending on the degree of ocular involvement (ie, anterior or posterior segment) [5]. Histoplasmosis may be effectively treated using itraconazole [119]. Blastomycosis may be treated with itraconazole or fluconazole, although the response is often poor [117,118].…”