A Dragon Felled by Bacteria

A 4-year-old bearded dragon was examined for dysecdysis and chronic skin lesions. Initial cytological examination of wound exudate revealed bacilli, cocci, and hyphal elements. Culture revealed Enterococcus spp and Devriesea agamarum. Despite a brief response to ceftiofur, voriconazole, and meloxicam, lesions recurred 3 months later, and culture revealed Clostridium and Chrysosporium spp; the animal was euthanized. Necropsy with histopathological examination revealed severe fatty degeneration and, in some areas, granulomatous hepatitis with intralesional fungal elements. Skin specimens showed severe granulomatous dermatitis with fungal elements. 

Bearded dragons, commonly kept as pets in America, are frequently presented for veterinary care for a variety of reasons, including skin disease. This article reported a novel case of fungal and bacterial coinfection in an adult bearded dragon. Results of cytology led to a tentative diagnosis of aspergillosis, but the organism Chrysosporium guarroi was eventually isolated as the causative fungal agent. The genus Chrysosporium includes fungal organisms that are often found on the skin of healthy reptiles, although several species, including C guarroi, have been shown to cause clinical disease. Results in this case demonstrated that cytology alone can be misleading, and that culture and biopsy can lead to a faster definitive diagnosis. The systemic spread of the Chrysosporium infection underscores the importance of a thorough diagnostic approach sooner, rather than later, when presented with dermatologic disease in reptiles. The information from this case is helpful to practitioners that see reptile patients, as skin disease is a common presenting complaint, and clinical signs and blood value changes are usually nonspecific for dermatomycoses in reptiles.—Grayson Doss, DVM