Cutaneous mycosis in a Barbastelle bat (Barbastella barbastellus) caused by Hyphopichia burtonii

A rare barbastelle bat (Barbastella barbastellus) died shortly after being found in emaciated condition in Devon, England. The skin over the muzzle and face was grossly thickened, crusty, and in places was sloughing and ulcerated. There were numerous nodules up to 3 mm in diameter on both wings and ear pinnae. Histologically, multiple foci of epidermal hyperplasia, hyperkeratosis, and crateriform erosions containing masses of fungal spores and septate hyphae were found in the wing. Epidermal hyperplasia and follicular hyperkeratosis, with fungal masses within keratinized follicles and also in fissured stratum corneum, were found in the pinna. Hyphae did not invade the dermis, and there was no inflammation, but there was multifocal serous exudation and crusting. No parasites or other significant organisms were identified. Microscopic and multiple cultural analyses of face and wing lesions demonstrated (10/10) a fine, septate fungus bearing laterally oval to clavate conidia; morphologically and culturally this was entirely consistent with Hyphopichia burtonii, and polymerase chain reaction analysis and sequencing gave 100% identity with the type strain. The organism isolated was morphologically consistent with that repeatedly seen in histology sections and demonstrates that although H. burtonii has not previously been recognized as a dermatophyte, it clearly has the ability to invade the skin of live bats. Although not identical, the lesions in this case show similarity with those of white nose syndrome and therefore H. burtonii should be considered as a potential pathogen of bats.