伴IgG4阳性浆细胞增多的皮肤Rosai-Dorfman病一例

患者女，28岁。右下肢皮肤硬化性红斑、结节2年，伴轻度痒痛。皮肤科检查示右侧大腿伸侧一约10 cm × 5 cm暗红色斑片，形状不规则，边界较清，表面散在或密集分布绿豆至黄豆大小紫红色、类圆形结节，表面光滑，质地稍硬；皮下可触及质地中等的结节，部分表面可见色素沉着；局部皮温高，触痛。皮损组织病理检查：真皮中上部结节状或片状分布单一核细胞，部分胞质淡染，并见较多浆细胞；免疫组化示S100强阳性；IgG4阳性浆细胞数量明显增多，每400倍视野 > 50个；IgG4阳性浆细胞在IgG阳性浆细胞中占45%。诊断：伴IgG4阳性浆细胞增多的皮肤Rosai?Dorfman病。

A case of cutaneous Rosai-Dorfman disease with increased IgG4-positive plasma cells

Li Lei, Xiao Yujuan, Yan Heng, Hao Jin, Diao QingchunSouthwest Medical University, Luzhou 646000, Sichuan, China （Li L）; Department of Dermatology, Chongqing Traditional Chinese Medicine Hospital, Chongqing First People′s Hospital, Chongqing 400011, China （Xiao YJ, Yan H, Hao J, Diao QC）Corresponding authors: Xiao Yujuan, Email: Xiaoyujuan1986@163.com; Hao Jin, Email: 284706197@qq.com【Abstract】 A 28-year-old female patient presented with indurated erythema and nodules on the right lower limb for 2 years, with mild itching and pain. Skin examination showed a well-circumscribed irregular dark red patch measuring about 10 cm × 5 cm in size on the extensor aspect of the right thigh. On the patch, there were scattered or densely distributed mung bean- to soybean-sized quasi-circular violaceous nodules with a smooth surface, which were hard on palpation. Subcutaneous nodules with medium hardness were found on palpation, and hyperpigmentation was observed on the surface of some nodules. Local skin temperature was increased, with tenderness on palpation. Histopathologically, mononuclear cells showed nodular or sheet-like distribution in the middle and upper dermis, some of which had pale-staining cytoplasm. Moreover, plenty of plasma cells were observed. Immunohistochemistry revealed that histiocytes were stained strongly positive for S100. The number of IgG4-positive plasma cells increased obviously, and was more than 50 per high-power field （× 200）. The proportion of IgG4-positive plasma cells in IgG-positive plasma cells was 45%. Finally, the patient was diagnosed with cutaneous Rosai-Dorfman disease with increased IgG4-positive plasma cells.