Unilateral linear capillaritis: two unusual Chinese cases.

Unilateral linear capillaritis (ULC) is a rare special variation of pigmented purpuric dermatosis (PPD), which is characterized clinically by linear or segmental distribution of pigmented purpuric macules located predominantly on the lower extremities and showing a favorable prognosis. In this case report, we describe two unusual cases of ULC, in one male and one female patient, with unilateral lesions involving the upper extremities that loosely follow the dermatome lines. Biopsy results revealed a common histopathology feature to PPD without heavy band-like infiltration in the upper dermis. On review 20 months after the onset, the eruptions of Patient 1 had spontaneously faded from parts of the affected area. Meanwhile, after a period of 18 months post onset, the eruptions of Patient 2 had became less visible after treatment with PUVA for 2 months, leaving a faded pigmentation.