Case presentation 

A 42-year-old woman presents with an eruption of papules and pustules on her chin and both cheeks (Figure). The lesions are painful and tender and associated with oedema and lymphadenopathy. The lesions appeared suddenly about three weeks ago. She is systemically well and afebrile. 

The patient has a history of minor acne as a teenager. She denies taking any medications. 

Skin swabs and scrapings have been taken from the lesions and returned negative results for bacteria, herpes viruses and fungi. She has been treated with oral flucloxacillin, but the condition has not improved.