Mycosis Due to Tropicoporus tropicalis (= Inonotus tropicalis) in a Domestic Dog.

Mycelial basidiomycetes rarely produce mycoses in animals including humans. We report a case of a 9-year-old female mongrel dog with lesions in the prescapular lymph nodes. The histopathology of a lymph node sample showed flexuous septate hyphae, and a sterile mold grew in culture from that specimen. DNA sequencing of the ITS region allowed us to identify the fungus as Tropicoporus tropicalis. The dog was treated with itraconazole, but it was euthanized six months later due to an unfavorable clinical outcome. Tropicoporus tropicalis is an infrequent pathogen of pets, and the use of molecular tools is needed for its identification. Animal infections due to T. tropicalis were not previously been reported in Argentina.