选择性IgA缺乏症

Selective IgA deficiency

报告1例选择性IgA缺乏症。患儿男,10岁。因皮下结节2年余就诊。血清IgA含量持续≤50 mg/L,皮损组织病理检查显示慢性炎症性改变,个别小血管纤维蛋白样变性,管腔狭窄、闭塞,红细胞外渗。免疫组化染色显示CD20少量表达,符合选择性IgA缺乏症的诊断。该病临床多并发反复肺部感染、自身免疫性疾病及肿瘤等。

A case of selective IgA deficiency is reported. A 10-year-old boy presented with subcutaneous nodules for 2 years. Laboratory study showed a stable lower concentration of serum IgA （≤50mg/L）. Histological examination on skin lesions revealed chronic cutaneous inflammation, with fibrinoid degeneration of blood vessels and the extravasation of erythrocytes. The narrow and even the closure of the vessels could be seen. Immunohistochemical study showed a mild positive staining for CD20. These findings are consistent with the selective IgA deficiency. There is a tendency in the patients with selective IgA deficiency to develop recurrent pulmonary infections, autoimmune disorders and malignancies.