A Clinical and Histopathologic Study of 20 Cases of Lichen Striatus

Background : Lichen striatus(LS) is an uncommon dermatosis that generally affects children. LS can usually be identified by clinical history and histology of typical lesions. However, the clinical manifestations and the histologic features are diverse. Objective : The aim of this study is to investigate clinical and histopathologic features of LS in Koreans. Methods : Total 20 patients were included in this study. Data compiled were sex, age, duration, distribution, symptoms, course and some histopathologic findings including hyperkeratosis acanthosis, dyskeratosis, basal degeneration, perivascular lymphocytic infiltration, lichenoid infiltration and eccrine sweat gland inflammation. Seventeen cases were studied further by immunohistochemistry for interleukin(IL)-1 to understand the biological basis of the disease. Results and Conclusions : 1. It was observed predominantly in females as the sex ratio of 1:2.3. the mean age was 5.5 years and the mean duration was 17.7 months. 2. Most patients were asymptomatic, but only five patients complained of mild itching. 3. It occured most frequently in the lower(11 cases) extremities, upper extremities(6 cases), axilla(1 case), anterior chest(1 case) and multiple location(1 case). Twelve cases consisted of erythematous papules, and the rest appeared as hypopigmented macules. 4. The lesions of 9 of 10 patients were almostly cleared in one year. Five of 9 consisted of erythematous papules and four hypopigmented macules. one who had no change consisted of hypopigmented macules. Therefore, there was no significant difference of prognosis between two groups. 5. Histologic examination revealed hyperkeratosis(65%), acanthosis(70%), parakeratosis(50%), exocytosis(95%), spongiosis(55%), dyskeratosis(70%), basal degeneration(90%) in epidermis, and colloid body(35%), lichenoid infiltration(65%), perivascular lymphocytic infiltration(95%) and eccrine sweat gland inflammation(50%) in dermis. 6. There was no significant difference between the papular group and the macular group, except parakeratosis and spongiosis, which were increased in the papular group as compared with the macular group. 7. IL-1 was expressed diffusely in keratinocytes, endothelial cells, hair follicles and eccrine sweat glands. IL-1 immunoreactivity was expressed in the entire epidermis in 15 of 17 cases. Most of the eccrine sweat glands showed intense immunolabeling in 12 of 17 cases. In contrast, only 2 cases of lichen planus were positive for epidermis and only 1 case for eccrine sweat gland. therefore, we think that it is helpful for discriminating two diseases immunohistochemically.