Oral Calcinosis Circumscripta Associated with Wasp (Hymenoptera vespidae) Sting in a Cat

In veterinary medicine, calcinosis circumscripta is a morphological diagnosis for which the cause may be known or idiopathic. The aetiology of the lesion must be investigated because the nature of the underlying disease process will dictate appropriate treatment. We present a case of oral calcinosis circumscripta in a cat caused by a wasp sting and associated with moderate unilateral facial oedema. Following corticosteroid therapy and oedema resolution, hyperaemic, circular, firm, elevated lesions were observed on the buccal mucosa and evolved into whitish, slightly elevated multifocal plaques with an irregular surface. As antibiotic and corticosteroid therapy was ineffective, an excisional biopsy was performed after 6 months of lesion development and a diagnosis of calcinosis circumscripta of dystrophic aetiology was made. To our knowledge, this is the first report of calcinosis circumscripta in association with an insect sting in an animal. Insect stings should be included in the differential diagnosis of calcinosis circumscripta in cats.