Department of Dermatology, Kinki University School of Medicine, Osakasayama, Japan.
Dermatology. 2010;220(2):169-72. doi: 10.1159/000277273. Epub 2010 Jan 26.
The mosaic pattern of phylloid hypomelanosis is mostly associated with chromosome 13 abnormalities. Recently, 1 case of hypermelanosis in a phylloid pattern has been described. We describe a 29-year-old Japanese male with mental retardation, phylloid hypermelanosis and histopathologically and ultrastructurally peculiar melanocytic nevi, which were associated with 3 aberrant chromosome 13 cell lines. The karyotyping of 30 peripheral blood lymphocytes showed 46,XY,r(13)(p11.2q34) in 21 cells, 45,XY,-13 in 7 cells and 46,XY,dic r(13)(p11.2q34) in 2 cells. Immunohistochemical staining with HMB45 showed a positive reaction to basal keratinocytes in phylloid hypermelanosis. HMB45 staining reacted to the nevus cells and keratinocytes in the melanocytic nevi. Electron microscopy of a specimen excised from a melanocytic nevus showed an unusual finding of aggregated and disfigured melanosomes in the keratinocytes. This case suggests that chromosome 13 abnormalities may be related to the development of phylloid hypermelanosis and the bizarre melanosomes in the keratinocytes of melanocytic nevi.
叶状色素减退症的镶嵌模式大多与 13 号染色体异常有关。最近，描述了 1 例叶状模式的色素沉着过度。我们描述了 1 例 29 岁的日本男性，表现为智力迟钝、叶状色素沉着过度和组织病理学及超微结构上特殊的黑色素细胞痣，这些与 3 条异常的 13 号染色体系有关。30 个外周血淋巴细胞的核型分析显示 21 个细胞中有 46,XY,r(13)(p11.2q34)，7 个细胞中有 45,XY,-13，2 个细胞中有 46,XY,dic r(13)(p11.2q34)。HMB45 的免疫组织化学染色在叶状色素减退症中对基底角质形成细胞呈阳性反应。HMB45 染色反应于黑色素细胞痣中的痣细胞和角质形成细胞。从黑色素细胞痣切除的标本的电子显微镜检查显示了角质形成细胞中聚集和变形的黑色素体的异常发现。该病例提示 13 号染色体异常可能与叶状色素减退症的发生和黑色素细胞痣的角质形成细胞中奇异的黑色素体有关。
