A 39-year-old man is referred by his GP to the on-call dermatologist with a 3-day history of a sore throat, painful mouth and blistering rash. One week prior to the onset of his painful mouth and rash he developed a sore on his upper lip. The sore on his upper lip and widespread blistering eruption had first occurred at the age of 7 years and had erupted on four previous occasions. He feels well in himself but is having difficulty eating due to his painful mouth. His past medical history includes diet-controlled diabetes, hypertension and hypercholesterolaemia. He was commenced on amlodipine and sim vastatin two years previously.&nbsp;

Examination&nbsp;

Annular target-like lesions are seen over his lips and blistering annular lesions over his hands, elbows and trunk. Within his mouth are painful blisters and eroded erythematous ulcers.

Investigations:

He was apyrexial, blood pressure was 140/88 mmHg, and pulse was normal. Viral and bacterial swabs, and skin biopsy were taken through a blister.

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