From the Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands; Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Nijmegen, The Netherlands; and
From the Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, The Netherlands;
Am J Clin Pathol. 2014 Jul;142(1):76-81. doi: 10.1309/AJCP41XCVBHEQCEL.
IgG4-related disease (IgG4-RD) is an increasingly recognized syndrome of unknown etiology that can affect a wide variety of organs. The commonly shared features include tumor-like swelling of the involved organs, a lymphoplasmacytic infiltrate enriched with polyclonal IgG4-positive plasma cells, variable degree of fibrosis, and elevated serum concentrations of polyclonal IgG4.
In a qualitative retrospective study, the electrophoretic characteristics of serum from patients with increased polyclonal IgG4 were studied to see if a reproducible pattern could be identified.
We demonstrate that a characteristic focal band bridging the β and γ fraction by serum protein electrophoresis may be a first serologic indication for IgG4-RD. We further demonstrate that significant κ:λ skewing can occur in the polyclonal IgG4 fraction.
The focal band detected by electrophoresis in sera from patients with IgG4-RD can be confirmed as polyclonal by immunofixation or immunosubtraction. Because these bands may be predominately of one light chain isotype, they could be misinterpreted as monoclonal gammopathies.
IgG4 相关疾病(IgG4-RD)是一种病因不明的日益被认识的综合征,可影响多种器官。其共同特征包括受累器官的肿瘤样肿胀、富含多克隆 IgG4 阳性浆细胞的淋巴浆细胞浸润、不同程度的纤维化和多克隆 IgG4 血清浓度升高。
在一项定性回顾性研究中,研究了血清 IgG4 升高患者的电泳特征,以确定是否可以识别出可重复的模式。
我们证明血清蛋白电泳中β和γ区之间的特征性焦点带可能是 IgG4-RD 的第一个血清学指标。我们进一步证明,多克隆 IgG4 部分可发生显著的κ:λ倾斜。
可通过免疫固定或免疫扣除法确认 IgG4-RD 患者血清中电泳检测到的焦点带为多克隆。因为这些带可能主要为一种轻链同种型,所以它们可能被误诊为单克隆丙种球蛋白病。