Department of Dermatology, Faculty of Medicine, Shimane University, Izumo, Japan.
Photodermatol Photoimmunol Photomed. 2010 Dec;26(6):333-5. doi: 10.1111/j.1600-0781.2010.00548.x.
Actinic lichen planus (ALP) is a rare variant of lichen planus in which lichen planus develops on the light-exposed areas of the skin. ALP is reported to occur in the African, Middle Eastern,and Indian populations, with very few cases reported in Caucasians. Here, we report a case of ALP in a Japanese man; to the best of our knowledge, this is the first reported occurrence of ALP in the East Asian population. A 52-year-old Japanese man developed recurrent painful annular erythema on the face and hands. Histopathological examination of his skin biopsy revealed lichenoid-type infiltrates of lymphocytes and histiocytes. We established a diagnosis of ALP on the basis of the distribution of eruptions only on the sunlight-exposed areas and histological findings. Oral administration of systemic steroids proved effective in improving his condition. Lichen planus is known to be induced by an irritant (Koebner phenomenon);we believe that our patient is genetically susceptible to sunlight exposure and that sunlight acted as an irritant stimulating the development of ALP.
光化性扁平苔藓（ALP）是扁平苔藓的一种罕见变异，其中扁平苔藓发生在皮肤的暴露于光的区域。据报道，ALP 发生在非洲、中东和印度人群中，而在白种人中很少有病例报告。在这里，我们报告了一例发生在日本男性中的 ALP；据我们所知，这是首例在东亚人群中报告的 ALP 病例。一名 52 岁的日本男性面部和手部反复出现疼痛性环状红斑。他的皮肤活检的组织病理学检查显示淋巴细胞和组织细胞呈苔藓样浸润。我们根据皮疹仅发生在阳光暴露部位和组织学发现，诊断为 ALP。口服全身类固醇治疗对改善他的病情有效。已知扁平苔藓是由刺激物（Koebner 现象）引起的；我们认为我们的患者对阳光暴露具有遗传易感性，阳光作为一种刺激物刺激了 ALP 的发展。
