Abstract:

Zhou Ying, Wang Sijie, Wu Yayun, Li Shijie, Li Zhaojun, Zhang Guoxue, Fan Yiming Department of Dermatology, Affiliated Hospital of Guangdong Medical University, Zhanjiang 524001, Guangdong, China （Zhou Y, Wu YY, Li SJ, Li ZJ, Zhang GX, Fan YM）; Electron Microscopy Room, Affiliated Hospital of Guangdong Medical University, Zhanjiang 524001, Guangdong, China （Wang SJ） Corresponding author: Fan Yiming, Email: ymfan1963@163.com 【Abstract】 Objective To investigate ultrahistopathological features of symmetrical acrokeratoderma. Methods Biopsy specimens were obtained from skin lesions and perilesional normal-appearing skin of 6 patients with symmetrical acrokeratoderma, as well as from normal skin of 3 healthy volunteers. Then, these skin specimens were subjected to transmission electron microscopy （TEM）. Results TEM showed obviously thickened stratum corneum, irregular morphology of keratinocytes and discontinuous cornified envelope. Aggregation and abnormal arrangement of keratin filaments occurred in all epidermal layers. Many vacuoles of different sizes were observed in the transitional zone between the stratum corneum and stratum granulosum. Hypogranulosis, abnormal shape and different sizes of keratohyalin granules, and reduction of membrane-coating granules were found in the stratum granulosum. Increased melanocytes with a large number of stage Ⅳ melanosomes in the cytoplasm were observed in the basal layers. Moreover, there was infiltration of a few lymphocytes in the superficial dermis. Perilesional normal-appearing skin tissues showed similar but milder ultrastructural changes. Conclusion Abnormal metabolism of keratins, epidermal differentiation complex proteins and lipids may exist in skin lesions of symmetrical acrokeratoderma, which may contribute to epidermal thickening and impairment of skin barrier function.