Resolution of exfoliative dermatitis and Malassezia pachydermatis overgrowth in a cat after surgical thymoma resection

A four-year-old, male neutered domestic shorthaired cat was presented with a two-week history of nasal and ocular discharge, generalised exfoliative dermatitis, intense pruritus, polydipsia, polyphagia, weight loss, intermittent hindlimb ataxia and lethargy. Cutaneous populations of Malassezia pachydermatis yeast organisms were found to be elevated. The generalised nature of the disease prompted survey radiography which revealed the presence of a cranial mediastinal mass which was subsequently resected and found to be a thymoma. Within six months of surgery, systemic and cutaneous signs had resolved and yeast counts had returned to normal, suggesting a causal relationship between the thymoma and the skin disease.