Clinical and Histopathological Characteristics of Trichrome Vitiligo / 대한피부과학회지

ABSTRACT

BACKGROUND: The term trichrome vitiligo was first suggested in 1964 by Fitzpatrick, There is a tan zone of varying width between the normal and the totally depigmented skin and this exhibits the intermediate hue. The etiopathogenesis and the histopathological characteristics of trichrome vitiligo are unknown. OBJECTIVE: Our purpose was to evaluate the clinical and histopathological characteristics of trichrome vitiligo. Methods . Four punch biopsies were taken from twenty-one patients with trichrome vitiligo; from vitiliginous skin, light brown skin, perilesional normal skin and normal skin as far as 5cm from the nearest vitiligo spot. The sections were stained with hematoxylin-eosin and S-100 protein. RESULTS: 1. Trichrome vitiligo occurred mostly on the trunk in active vitiligo vulgaris. 2. Vacuolar degeneration of the basal cell layer in the epidermis and mild inflammatory cell infiltration in the epidermis and dermis were more prominent in light, brown skin and perilesional normal skin than in vitiliginous skin and normal skin of trichrome vitiligo. 3. The number of melanocytes was decreased in light brown skin compared with perilesional normal skin(p<0.05), and in vitiligonous skin compared with light brown skin(p<0.05), 4. A few melanocytes were also observed in vitiliginous skin of trichrome vitiligo. 5. In the trichrome vitiligo, the result of treatment was excellent in cases of systemic PUVA therapy. CONCLUSION: Melanocytes, keratinocytes and lymphocytes may be involved in the genesis of depigmentation in trichrome vitiligo, which means cell-mediated immunity may play an important role in the pathogenesis of trichrome vitiligo.