Hagari Y, Mihara M, Hagari S
Department of Dermatology, Faculty of Medicine, Tottori University, Yonago, Japan.
Br J Dermatol. 1996 Oct;135(4):630-3.
We report nodular localized cutaneous amyloidosis arising in a 74-year-old woman as a single nodule at the left angle of the mouth. Histological examination revealed eosinophilic material deposited in the dermis, identified as amyloid by staining with Dylon stain, and antiamyloid P component, and by electron microscopy. The amyloid material was further determined immunohistochemically to be of AL fibril protein type derived from lambda light chains. Infiltrating plasma cells, around blood vessels in the dermis, stained monotypically with anti-lambda antibody, suggesting plasma cell monoclonality. Semi-nested polymerase chain reaction (PCR), for rearrangement of immunoglobulin heavy chain gene using paraffin-embedded sections, yielded two distinct amplified bands, indicating monoclonality of the infiltrating plasma cells. These findings support the hypothesis that primary localized nodular amyloidosis involves local accumulation of monoclonal plasma cells and their secreted products. The two amplified bands observed on PCR may, in the present case, reflect abnormal secretion of immunoglobulin light chains.
我们报告了一名74岁女性发生的结节性局限性皮肤淀粉样变性，表现为左口角处的单个结节。组织学检查显示嗜酸性物质沉积于真皮，经Dylon染色、抗淀粉样蛋白P成分染色及电子显微镜检查确定为淀粉样物质。免疫组织化学进一步确定淀粉样物质为源自λ轻链的AL纤维蛋白类型。真皮血管周围浸润的浆细胞用抗λ抗体单克隆染色，提示浆细胞单克隆性。使用石蜡包埋切片进行免疫球蛋白重链基因重排的半巢式聚合酶链反应（PCR）产生了两条不同的扩增带，表明浸润浆细胞的单克隆性。这些发现支持了原发性局限性结节性淀粉样变性涉及单克隆浆细胞及其分泌产物局部积聚的假说。在本病例中，PCR上观察到的两条扩增带可能反映了免疫球蛋白轻链的异常分泌。
