Deep fungal dermatitis in three inland bearded dragons (Pogona vitticeps) caused by theChrysosporiumanamorph ofNannizziopsis vriesii

Abstract

The Chrysosporium anamorph of Nannizziopsis vriesii (CANV), a keratinophilic fungus that naturally and experimentally causes severe and often fatal dermatitis in multiple reptile species, was isolated in pure culture from skin samples of three inland bearded dragons (Pogona vitticeps) with deep granulomatous dermatomycosis. The first animal presented with a focal maxillary swelling involving the skin and gingiva. This lizard died while undergoing itraconazole and topical miconazole therapy. The second presented with focally extensive discoloration and thickening of the skin of the ventrum and was euthanized after 10 weeks of itraconazole therapy. A third lizard presented with hyperkeratotic exudative dermatitis on a markedly swollen forelimb. Amputation and itraconazole therapy resulted in a clinical cure. Histopathology of tissue biopsies in all cases demonstrated granulomatous dermatitis with intralesional hyphae morphologically consistent with those produced by the CANV. The second lizard also had granulomatous hepatitis with intralesional hyphae. Evidence in this report suggests that the CANV is the etiologic agent of an emerging condition in captive bearded dragons that has been called 'yellow fungus disease'.

Molecular Characterization of Reptile Pathogens Currently Known as Members of the Chrysosporium Anamorph of Nannizziopsis vriesii Complex and Relationship with Some Human-Associated Isolates

“…Most data on antifungal therapy concerns N. guarroi. Itraconazole failed to resolve infections in two of three bearded dragons after 6 to 8 weeks, but a third was cured with itraconazole and amputation of the affected limb (7). Only seven of 13 bearded dragons responded to itraconazole together with topical clotrimazole (9).…”

“…Infections with the CANV and Chrysosporium species have been documented in lizards, including chameleons (Calumna parsonii, Furcifer lateralis, Trioceros (formerly Chamaeleo) jacksonii (3), inland (Pogona vitticeps) (7)(8)(9) and coastal bearded dragons (Pogona barbata) (10), green iguanas (Iguana iguana) (11,12), ameivas (Ameiva sp., Ameiva chaitzami) (13,14), day geckos (Phelsuma sp.) (15), sungazers (Cordylus giganteus) (16), brown anoles (Anolis sagrei) (17), leopard geckos (Eublepharis macularius) (18), terrestrial and aquatic snakes, including brown tree snakes (Boiga irregularis) (19), a garter snake (Thamnophis sp.)…”

Dermatomycosis in three central bearded dragons (Pogona vitticeps) associated with Nannizziopsis chlamydospora

“…[1][2][3][4][5]9 Captive-born bearded dragons are affected as well as wild-caught animals. 4 Clinical signs include swellings and discolored, crusty, ulcerative to necrotic skin lesions of the facial region, body, limbs, or tail.…”

“…6 Hyphomycete fungi of the family Nannizziopsiaceae isolated from bearded dragons include N. chlamydospora, N. draconii, N. barbata, N. guarroi, and N. vriesii. [1][2][3][4][5][6][7]9 Clinical signs include swellings, subcutaneous masses, and skin lesions. [1][2][3][4][5]9 Antifungal treatments were not always successful in resolving the skin lesions, or skin lesions recrudesce, resulting in the animals being euthanized and, at postmortem, systemic fungal infections were occasionally identified.…”

“…1-7,9 Clinical signs include swellings, subcutaneous masses, and skin lesions. [1][2][3][4][5]9 Antifungal treatments were not always successful in resolving the skin lesions, or skin lesions recrudesce, resulting in the animals being euthanized and, at postmortem, systemic fungal infections were occasionally identified.2,4,5 Three central bearded dragons (syn. inland bearded dragon; Pogona vitticeps) from the same owner were privately held as companion animals.…”