History A 67-year-old woman presented to the accident and emergency department with a 6-day history of severe, painful and progressive blistering. 2 months earlier she had a worsening ‘burning itchy’ eruption. At that time, she was diagnosed with urticaria and started on a regular antihistamine with no benefit. Two weeks ago, she had painful oral erosions. Her past medical history includes a cholecystectomy and borderline abnormal thyroid function tests, for which she was not on any therapy. She was an ex-smoker.
There were no other remarkable features in her history. Examination The patient was uncomfortable at rest and it was painful for her to move during the examination. She had two small (< 5 mm) healing erosions on her right buccal mucosa and a fresh tense blister (~7 mm) on her hard palate. The rest of her oral examination was normal. She has a symmetrical erythematous urticated…
