chapter 35 Mycoses, Deep.......................................
DEFINITION/OVERVIEW
Cryptococcosis, coccidioidomycosis, blastomycosis: localized or disseminated sys-
temic fungal infections.
Clinical signs vary with the organ system involved.
ETIOLOGY/PATHOPHYSIOLOGY
Cryptococcus neoformansandC. gattii:ubiquitous yeast-like organism;C. neoformans
associated with bird droppings and decaying vegetation;C. gattiiendemic in the envi-
ronment as well as in humans and small ruminants.Coccidioides immitis: dimorphic saprophytic fungus; prefers warm and dry environ-
ments with alkaline soil (southwestern US).
Blastomyces dermatitidis(Mississippi, Ohio, Tennessee river basins, and parts of
Wisconsin) are soil-borne fungal organisms.
CLINICAL FEATURES
Cryptococcosis
Most common systemic fungal infection in cats; seven times more common in cats;
rare in dogs.
Inhalation of the yeast organisms causes focal infection in the nasal passages; infection
rarely caused by inoculation of organism through a wound; primary entry via the
gastrointestinal tract may occur.Disseminated form spreads hematogenously from the nasal passages to the brain,
eyes, lungs, and other tissues or by extension to the skin of the nose, eye, retroor-
bital tissue, and draining lymph nodes (lymphadenopathy).Immunosuppression (especially resulting from glucocorticoid administration) is a
risk factor for development of disseminated disease (Figures 35.1, 35.2).
Associated with fever, anorexia, nasal discharge, skin nodules/ulceration, lethargy,
neurologic signs (seizures, ataxia, paresis, blindness).
Blackwell’s Five-Minute Veterinary Consult Clinical Companion: Small Animal Dermatology, Third Edition.
Karen Helton Rhodes and Alexander H. Werner.
©2018 John Wiley & Sons, Inc. Published 2018 by John Wiley & Sons, Inc.
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