Nambiar Sudheer, Oliver Tony I.
Cancer Treatment Centers of America
University Of South Dakota
IgG4-related disease (IgG4-RD) is known as an IgG4-related systemic disease, hyper-IgG4 disease, IgG4-related autoimmune disease, IgG4-associated disease, IgG4-related sclerosing disease, and IgG4-syndrome. It is a multi-organ, fibro-inflammatory condition with tumefactive lesions of unknown etiology and characteristic histopathological features. Virtually any organ can be involved, but the most commonly involved organs are the pancreas, kidneys, orbital adnexal structures, salivary glands, and retroperitoneum. The pathological hallmark of this disease is dense lymphoplasmacytic infiltrate with IgG4 positive plasma cells, storiform fibrosis, obliterative phlebitis, and a variable amount of eosinophils. Elevated levels of serum IgG4 is frequent. The pathology is very specific and looks similar in all organs. Because of this finding, it is considered to be analogous to systemic sarcoidosis. IgG4-RD affected patients are often misdiagnosed as having a malignancy since the lesions can mimic tumors, infections, or immune-mediated diseases. This is because of the lack of a systemic approach, and hence, this disease is underdiagnosed. These patients usually have a good recovery after being treated with systemic glucocorticosteroids. The response to steroids is so dramatic that it is has been suggested as one diagnostic criterion for the disease.
IgG4相关疾病（IgG4-RD）被称为IgG4相关性全身性疾病、高IgG4疾病、IgG4相关自身免疫性疾病、IgG4相关疾病、IgG4相关硬化性疾病和IgG4综合征。它是一种多器官的纤维炎症性疾病，具有病因不明的肿块性病变和特征性组织病理学特征。实际上任何器官都可能受累，但最常受累的器官是胰腺、肾脏、眼眶附属结构、唾液腺和腹膜后。这种疾病的病理特征是密集的淋巴细胞和浆细胞浸润，伴有IgG4阳性浆细胞、席纹状纤维化、闭塞性静脉炎和数量不等的嗜酸性粒细胞。血清IgG4水平升高很常见。其病理非常特异，在所有器官中表现相似。基于这一发现，它被认为类似于系统性结节病。IgG4-RD患者常被误诊为患有恶性肿瘤，因为病变可类似肿瘤、感染或免疫介导性疾病。这是由于缺乏系统性的诊断方法，因此该疾病诊断不足。这些患者在接受全身性糖皮质激素治疗后通常恢复良好。对类固醇的反应非常显著，以至于有人建议将其作为该疾病的一项诊断标准。
