IgG4-related conditions affecting the digestive tract are part of a multi-organ fibro-inflammatory disorder termed IgG4-related disease (IgG4-RD), with autoimmune pancreatitis and IgG4-related cholangitis being the most prominent manifestations. Gastrointestinal symptoms include jaundice, weight loss, abdominal pain, biliary strictures, and pancreatic and hepatic masses that mimic malignant diseases. IgG4-RD manifestations occur less frequently elsewhere in the digestive tract, namely in the oesophagus, retroperitoneum or intestine. Evidence-based European guidelines frame the current state-of-the-art in the diagnosis and management of IgG4-related digestive tract disease. Diagnosis is based on histology (if available), imaging, serology, other organ involvement and response to therapy (HISORt criteria). Few biomarkers beyond serum IgG4 concentrations are reliable. The first-line therapy (glucocorticoids) is swiftly effective but disease flares are common at low doses or after tapering. Second-line therapy might consist of other immunosuppressive drugs such as thiopurines or rituximab. Further trials, for example, of anti-CD19 drugs, are ongoing. Although an association between IgG4-RD and the development of malignancies has been postulated, the true nature of this relationship remains uncertain at this time.

影响消化道的 IgG4 相关疾病是称为 IgG4 相关疾病 (IgG4-RD) 的多器官纤维炎症性疾病的一部分，其中自身免疫性胰腺炎和 IgG4 相关胆管炎是最突出的表现。胃肠道症状包括黄疸、体重减轻、腹痛、胆道狭窄以及类似于恶性疾病的胰腺和肝脏肿块。IgG4-RD 表现较少出现在消化道其他部位，即食道、腹膜后或肠道。以证据为基础的欧洲指南框架了当前 IgG4 相关消化道疾病诊断和管理的最新技术。诊断基于组织学（如果有）、影像学、血清学、其他器官受累和对治疗的反应（HISORt 标准）。除了血清 IgG4 浓度之外，很少有生物标志物是可靠的。一线治疗（糖皮质激素）迅速有效，但在低剂量或逐渐减量后疾病发作很常见。二线治疗可能包括其他免疫抑制药物，如硫嘌呤或利妥昔单抗。例如，抗 CD19 药物的进一步试验正在进行中。尽管已经假设 IgG4-RD 与恶性肿瘤的发展之间存在关联，但目前这种关系的真实性质仍不确定。