Nasal phaeohyphomycosis in a cat caused by Cladophialophora boppii.

Phaeohyphomycosis is an opportunistic mycosis caused by dematiaceous fungi, typically affecting the cutaneous or subcutaneous tissues of the facial region and distal extremities in cats. This report documents a case of Cladophialophora boppii infection in a cat. A 7-year-old neutered male domestic shorthair cat was presented with a chronic, pigmented nasal lesion, non-productive sneezing, and stertor. Computed tomography, rhinoscopy, and tissue sampling were performed. Fungal culture and molecular sequencing confirmed the diagnosis. Oral itraconazole treatment failed to arrest progression, necessitating delayed nasal planectomy. Despite transient remission, disease recurred, requiring repeat surgical debridement, and prolonged antifungal treatment. Clinical resolution was ultimately achieved, with marked improvement in the cat's quality of life. Identification of a novel species of phaeohyphomycosis in a cat emphasizes the need for increased awareness of emerging fungal pathogens that can precipitate considerable morbidity, particularly in the absence of prompt aggressive intervention.