免疫球蛋白G4相关疾病（IgG4-RD）是一种最近被描述的罕见系统纤维炎性疾病，每年发病率估计不到10万人中的1例。该疾病可以影响几乎任何器官，并表现出统一的组织病理学特征。最近，已经确定了四个亚组的患者：肝胆、头颈、米库利兹综合症和腹膜后纤维化，它们表明该疾病主要针对腹部和耳鼻喉的倾向。然而，胸部受累并不罕见。在系统IgG4-RD患者中，可在多达30％的病例中检测到胸部受累，并且该疾病在大约10％的病例中仅表现为胸部症状，如呼吸困难、咳嗽或胸痛。胸部CT表现是异质性的，主要包括支气管血管周围的增厚、结节、地玻璃状浸润和淋巴结肿大。没有特异性的诊断测试可用于IgG4-RD胸部受累，而它可能模拟恶性肿瘤或血管炎。因此，需要谨慎对待以做出准确的诊断：需要寻找多器官受累表现、升高的血清IgG4水平、浆细胞前体细胞的循环水平以及病理证据。虽然很有说服力，但是多克隆IgG4淋巴浆细胞浸润、纺锤形纤维化或闭塞性静脉炎的存在都不足以确认组织学诊断。建议作为一线治疗使用类固醇。在复发或类固醇耐药性疾病的罕见情况下，可以使用利妥昔单抗或疾病修饰抗风湿药物。在本综述中，我们总结了有关IgG4-RD胸部受累的病理生理学、流行病学、诊断方法（临床-生物学-影像-组织学）和治疗的最新知识。 ©2022作者。Respirology由John Wiley＆Sons Australia,Ltd代表亚太呼吸病学会出版。

Immunoglobulin G4-related disease (IgG4-RD) is a recently described rare systemic fibroinflammatory disease with an estimated incidence of less than 1 in 100,000 persons per year. The disease can affect virtually any organ and is characterized by unifying histopathological findings. Recently, four subgroups of patients have been characterized: hepatobiliary, head and neck, Mikulicz syndrome and retroperitoneal fibrosis, who illustrate the mainly abdominal and ENT tropism of the disease. Yet, thoracic involvement is not uncommon. It can be detected in up to 30% of patients with systemic IgG4-RD and is the exclusive manifestation of the disease in about 10% of cases. Clinical symptoms are nonspecific and may include dyspnoea, cough or chest pain. Chest CT findings are heterogeneous and primarily include peribronchovascular thickening, nodules, ground-glass opacities and lymphadenopathy. There is no specific diagnostic test for IgG4-RD thoracic involvement, which may mimic malignancy or vasculitis. Therefore, a cautious approach is needed to make an accurate diagnosis: a search for extra-thoracic manifestations, elevated serum IgG4 levels, circulating levels of plasmablasts and pathologic evidence of disease is warranted. Although very suggestive, neither the presence of a polyclonal IgG4 lymphoplasmacytic infiltrate, storiform fibrosis or obliterative phlebitis are sufficient to confirm the histological diagnosis. Steroids are recommended as first-line therapy. Rituximab or disease-modifying antirheumatic drugs may be used in relapsed or rare cases of steroid-refractory disease. In this review, we summarize current knowledge regarding the pathophysiology, epidemiology, diagnostic modalities (clinical-biological-imaging-histopathology) and treatment of IgG4-RD thoracic involvement.© 2022 The Authors. Respirology published by John Wiley & Sons Australia, Ltd on behalf of Asian Pacific Society of Respirology.