Cryptococcus gattii with bimorphic colony types in a dog in western Oregon: additional evidence for expansion of the Vancouver Island outbreak.

TitleCryptococcus gattii with bimorphic colony types in a dog in western Oregon: additional evidence for expansion of the Vancouver Island outbreak.
Publication TypeJournal Article
Year of Publication2009
AuthorsByrnes EJ, Bildfell RJ, Dearing PL, Valentine BA, Heitman J
JournalJournal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc
Volume21
Issue1
Pagination133-6
Date Published2009 Jan
ISSN1040-6387
KeywordsAnimals, British Columbia, Central Nervous System Infections, Cryptococcosis, Cryptococcus, Disease Outbreaks, Dog Diseases, Dogs, Female, Oregon
Abstract

Cryptococcus gattii was isolated from a 1.5-year-old dog with systemic cryptococcosis in Oregon. The dog had no link to Vancouver Island or British Columbia, Canada. Samples from a nasal swab and from a granulomatous mass within the cranial cavity were pooled for culture. Colonies on Sabouraud dextrose agar were mucoid and exhibited bimorphic morphology, melanin-pigmented and unpigmented. Pigmented colonies were encapsulated budding spherical yeast, whereas unpigmented colonies were of unencapsulated ovoid budding yeast. In addition to defective melanin production, the unpigmented colony type exhibited defective mating. Genetic analysis by high-resolution multilocus sequence typing revealed that the 2 isolates are genetically identical at 8 unlinked loci tested and that the 2 isolates are both the VGIIa Vancouver Island major genotype. Findings are consistent with expansion of the Vancouver Island outbreak onto the mainland Pacific Northwest region of the United States.

Alternate JournalJ. Vet. Diagn. Invest.