A case of generalized lichen nitidus with Koebner's phenomenon.

A 12-year-old boy was seen in our department with a three year history of eruptions on his back consisting of normal colored or slightly reddish, pinhead-sized papules, which had gradually spread to his trunk within the previous year. Four days before the first visit, May 13, 1992, the eruption involved his entire extremities. On the back side of his lumbar region, Koebner's phenomenon was observed. He had received several medications for more than two years to treat this eruption in several hospitals, but none were effective. He was in good general health. Mantoux reaction was negative two months after BCG injection. Histopathologic features of the papules included focal epidermal hyperplasia and elongation of the rete ridges in a narrow area and a well demarcated dense lymphohistiocytic infiltrate on the papillar layer. Biscoclaurine alkaloids (20 mg/day) and Jumi-haidoku-to (TJ-6; 7.5 g/day) were administered to the patient after the biopsy. No topical ointments were applied. Two weeks after of these treatments, he reported moderate pruritus on the back. The eruption diminished rapidly within 2 weeks after the therapy began. Almost all the eruptions were cured within one year. Mantoux reaction developed 8 x 8 mm erythema two and half months after the treatment began, and it was significantly positive (23 x 30 mm) 6 months later.