11例黄褐斑面部皮损组织病理及超微病理

Histopathological and ultrastructural study on face lesions of eleven cases with melasma

目的:比较黄褐斑患者面部皮损及临近非皮损的组织病理及超微病理学特点。方法:选择11例门诊确诊的黄褐斑患者,对皮损和临近非皮损取活检,分别进行苏木素-伊红、Fontana-M asson染色、HMB45、NK I/beteb免疫组化染色和电镜观察。计算机图像分析技术量化分析。结果:同邻近正常皮损相比,黄褐斑皮损表皮全层色素明显增加,基底层黑素细胞数量无改变。真皮载色素细胞增加。超微结构显示黄褐斑皮损黑素细胞内线粒体、高尔基体、粗质内质网、核糖体及成熟黑素小体数量增加,角质形成细胞内有大量吞噬的Ⅲ期、Ⅳ期黑素小体。结论:黄褐斑皮损的色素增加,可能与多种因素引起的黑素细胞功能活跃和黑素颗粒在表皮内转运增加有关。

Objective：To study the histopathological features of facial melasma skin in comparison with adjacent normal skin. Methods：Biopsies were taken from both melasma lesional skin and adjacent perilesional normal skin in 11 cases with melasma. The sections were stained by using haematoxylin and eosin, Fontana-Masson and immunostaining for melanocytes. The ultrastructure of the skin was also examined. Results： The amount of melanin was significantly increased in all epidermal layers in melasma skin. The staining intensity of epidermal melanocytes increased in melasma lesions. But the number of melanocytes was not changed. Melanosomes increased in number and were more widely dispersed in the keratinocytes of the lesional skin. Lesional melanocytes had many more mature melanosome, mitochondria, Golgi apparatus, rough endoplasmic reticulum and ribosomes in their cytoplasm. Conclusion：Melasma is characterized by epidermal hyperpigmentation, which are possibly caused both by an increased activity of melanogenic enzymes and by an increased function of melanosome transfer.