12. Blisters on lips

A 31-year-old secretary complained of recurrent lip blistering. She had suffered from blisters on the lips since she was a teenager. The blistering affected either one or both lips, and appeared spontaneously or after sun exposure. She was aware of no other precipitants and had no other mucocutaneous, ocular or genital complaints and no fever or allergies. She was on no medication. Her medical history was otherwise clear, apart from hay fever. She was teetotal.

Extra-oral examination revealed no significant abnormalities apart from the lip blistering as shown (Figure 1), and specifically no cervical lymph node enlargement, or cranial nerve, salivary or temporomandibular joint abnormalities or pyrexia. Oral examination revealed no abnormalities whatsoever.