Oral eosinophilic granuloma in three cavalier King Charles spaniels.

Oral eosinophilic granuloma is a rare and enigmatic disease in dogs. The clinical, haematological, cytological and histopathological features of three unrelated Cavalier King Charles spaniels with oral ulcers are presented. The disease was characterised by granuloma or plaque formation in the oral cavity. Common clinical signs were clearing the throat, swallowing problems, coughing during and after meals, reduced appetite and difficulty in eating. Haematological findings were not specific. Cytology was considered easier to perform than tissue biopsy due to friability of the tissue, but could not be used to confirm a granuloma diagnosis. The diagnosis of oral eosinophilic granuloma was verified histopathologically in each case. Response to glucocorticoid therapy varied, from complete remission to lack of any visible effect, leading to a guarded prognosis. The aetiology of the disease was not determined; however, the gross and microscopic morphologies of the lesions, their location and the response to corticosteroid therapy was suggestive of hypersensitivity.