Multiple annular lesions on the legs

A 65 year old woman presented with a six week history of an asymptomatic eruption on her thighs. She described a “50 pence” sized area of redness on her right thigh that had gradually expanded in size. Within two weeks of the initial lesion, a second expanding area of erythema developed on the left thigh. She was systemically well, with no fevers, lethargy, or arthralgia. Her only medical history of note was breast carcinoma, which had been treated with a mastectomy, and she had been taking oral tamoxifen for six months. When the eruption first occurred in the summer, she was on holiday in the Limousin region of France (a woodland area), although she did not remember having tick bites. On examination, three 15-20 cm non-scaly patches with a macular erythematous edge were noted on her thighs (fig 1⇓).