Histopathologic features in vitiligo.
Nevus depigmentosus is a congenital disorder characterized by a nonprogressive hypopigmented lesion, which may not be apparent at birth. Thus, it is sometimes difficult to differentiate vitiligo from nevus depigmentosus only by clinical features. We postulated that the histologic changes in lesional and perilesional skin might be different in the 2 conditions. We took biopsies from both lesional and perilesional skin of 100 cases of vitiligo to assess the number of melanocytes, the amount of melanin, dermal inflammatory infiltrate, and other changes. We compared them with 30 cases of nevus depigmentosus. Histologically, lesions of vitiligo showed more basal hypopigmentation and dermal inflammation than perilesional normal skin. With Fontana-Masson staining, 16% of cases of vitiligo showed the presence of melanin. The ratio of pigmented area to epidermal area was 0.06% in vitiligo, whereas 17% in perilesional normal skin and 8.9% in nevus depigmentosus. In NKI/beteb staining, 12% of vitiligo showed the presence of melanocytes, and their average number was 7.68 per square millimeter. The number of melanocytes was also decreased in nevus depigmentosus but not as much as in vitiligo. We also confirmed the presence of melanocytes in 1 of 3 cases of vitiligo by electron microscopy. In conclusion, there are a few melanocytes and melanin in some cases of vitiligo. Therefore, the diagnosis of vitiligo should be made considering these points.
Kim
You Chan
YC
Department of Dermatology, Ajou University School of Medicine, Suwon, Korea. maychan@ ajou.ac.kr
Kim
Yun Jeon
YJ
Kang
Hee Young
HY
Sohn
Seonghyang
S
Lee
Eun-So
ES
D000293:Adolescent; D000328:Adult; D001707:Biopsy, Needle; D016022:Case-Control Studies; D003872:Dermatitis / Q000473:pathology*; D005260:Female; D006801:Humans; D017496:Hypopigmentation / Q000378:metabolism / Q000473:pathology; D007090:Image Interpretation, Computer-Assisted; D007150:Immunohistochemistry; D008297:Male; D008543:Melanins / Q000378:metabolism*; D008544:Melanocytes / Q000166:cytology / Q000378:metabolism*; D008854:Microscopy, Electron; D008875:Middle Aged; D011336:Probability; D012016:Reference Values; D012680:Sensitivity and Specificity; D012867:Skin / Q000473:pathology / Q000648:ultrastructure; D018709:Statistics, Nonparametric; D014820:Vitiligo / Q000473:pathology*
D008543:Melanins