Cryptococcosis in dogs: a retrospective study of 20 consecutive cases

The clinical and mycological findings in 20 consecutive cases of cryptococcosis evaluated between 1981 and 1995 were analysed retrospectively. Typically, young adult dogs (median age 2 years) of either sex were affected. Dobermann Pinschers and Great Danes were significantly over-represented in relation to other breeds and crossbred dogs, and there was no trend for cryptococcosis to be acquired at a particular time of year. Cryptococcus neoformans was cultured from 18 dogs, with 16 isolates further characterized. Of these, C. neoformans var. neoformans was isolated from 12 cases, while the remaining four strains were C. neoformans var. gattii. Dogs with C. neoformans var. gattii infections resided in rural (two cases) or suburban (two cases) environments. Ten dogs were presented as a result of infection of structures inside, adjacent to, or contiguous with the nasal cavity. Seven dogs were presented primarily for signs of central nervous system disease, of which at least three also had cryptococcal rhinosinusitis. One dog had cryptococcal pneumonia and also possible mycotic rhinitis, another had disseminated disease with lymph node and skin involvement, while the last dog was presented for vomiting referable to cryptococcal mesenteric lymphadenitis. Treatment consisting of surgery and/or antifungal drug therapy was successful in the majority of animals in which it was attempted, including two of three cases with meningo-encephalitis.