Zaynoun S T, Aftimos B G, Tenekjian K K, Bahuth N, Kurban A K
Br J Dermatol. 1983 Jan;108(1):83-90. doi: 10.1111/j.1365-2133.1983.tb04582.x.
Nine patients with extensive pityriasis alba were studied using histopathological and histochemical techniques and electron microscopy. There was a reduction in the density of functional melanocytes in the affected areas without any change in their cytoplasmic activity. The melanosomes tended to be fewer and smaller, but their distribution pattern in the keratinocytes was normal. Melanosomal transfer to keratinocytes was generally not disturbed. The histology was non-specific. Hyperkeratosis and parakeratosis were not consistently present, and it seems unlikely that they played a significant role in the pathogenesis of the hypomelanosis. A variable degree of intercellular oedema and intracytoplasmic lipid droplets were present. The hypopigmentation may thus be due primarily to the reduced numbers of active melanocytes and a decrease in number and size of melanosomes in the affected skin.
采用组织病理学、组织化学技术及电子显微镜对9例泛发性白色糠疹患者进行了研究。患区功能性黑素细胞密度降低，但其胞质活性无变化。黑素小体数量趋于减少且体积变小，但其在角质形成细胞中的分布模式正常。黑素小体向角质形成细胞的转运通常未受干扰。组织学表现无特异性。角化过度和角化不全并非始终存在，它们似乎不太可能在色素减退的发病机制中起重要作用。存在不同程度的细胞间水肿和胞质内脂滴。因此，色素减退可能主要归因于受累皮肤中活性黑素细胞数量减少以及黑素小体数量和大小的减少。
