Key point: The shallow ulceration surrounded by a ring of erythema is characteristic for aphthous ulcers (canker sores). Her otherwise negative history rules out Behcet’s disease.
Treatment: The patient was given desoximetasone ointment to apply to the lesion 3 or 4 times daily. This led to prompt ulcer resolution.
Note: Prolonged administration of 1000 µg/d of sublingual vitamin B12 reportedly has been effective for reducing, or even preventing, oral aphthosis in those who have very frequent outbreaks of this often debilitating disease.