Recalcitrant oral pyoderma gangrenosum in a child responsive to cyclosporine.

We report a case of recalcitrant pyoderma gangrenosum which developed on the tongue of an 8-year-old, previously healthy boy without any systemic associated disease. The lesion was confined to the tongue and was not responsive to conventional treatment with prednisolone and sulfa drug, but it showed dramatic improvement with oral cyclosporine therapy. In addition, the histopathology of the lesion included many eosinophils, which caused difficulties in diagnosis to differentiate this condition from other oral ulcerative diseases showing tissue eosinophilia including eosinophilic ulcer of the tongue.