IgG4-related sclerosing cholangitis (IgG4-SC) can be classified into four types based on cholangiographic findings and regions of biliary stricture. This cholangiographic classification is useful to differentiate IgG4-SC from mimickers including cholangiocarcinoma, primary sclerosing cholangitis, and pancreatic cancer. Autoimmune pancreatitis (AIP) is a valuable clue for the diagnosis of IgG4-SC because the two are frequently found in association with each other. Two sets of diagnostic criteria for IgG4-SC have been proposed. In Japan, the clinical diagnostic criteria 2020 were recently developed. These clinical diagnostic criteria include narrowing of the intrahepatic and/or extrahepatic bile duct, thickening of the bile duct wall, serological findings, pathological findings, other organ involvement, and effectiveness of steroid therapy. When these criteria are applied, IgG4-SC is initially classified as associated or not associated with AIP, and cholangiographic classification is used for differential diagnosis. In most instances, IgG4-SC can be diagnosed on the basis of clinical diagnostic criteria. However, it is challenging to diagnose isolated IgG4-SC or IgG4-SC not associated with AIP. Here, we review the classification and diagnostic criteria for IgG4-SC, specifically focusing on the clinical diagnostic criteria 2020 and a large IgG4-SC case series from a nationwide survey in Japan.

中文翻译：

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IgG4 相关硬化性胆管炎的分类和诊断标准。

IgG4 相关硬化性胆管炎 (IgG4-SC) 根据胆管造影结果和胆道狭窄区域可分为四种类型。这种胆管造影分类有助于区分 IgG4-SC 与模仿者，包括胆管癌、原发性硬化性胆管炎和胰腺癌。自身免疫性胰腺炎 (AIP) 是诊断 IgG4-SC 的重要线索，因为这两者经常被发现相互关联。已经提出了两套 IgG4-SC 的诊断标准。在日本，最近制定了 2020 年临床诊断标准。这些临床诊断标准包括肝内和/或肝外胆管狭窄、胆管壁增厚、血清学发现、病理学发现、其他器官受累和类固醇治疗的有效性。当应用这些标准时，IgG4-SC 最初被分类为与 AIP 相关或不相关，并且胆管造影分类用于鉴别诊断。在大多数情况下，可以根据临床诊断标准诊断 IgG4-SC。然而，诊断孤立的 IgG4-SC 或与 AIP 无关的 IgG4-SC 具有挑战性。在这里，我们回顾了 IgG4-SC 的分类和诊断标准，特别关注 2020 年临床诊断标准和来自日本全国调查的大型 IgG4-SC 病例系列。诊断孤立的 IgG4-SC 或与 AIP 无关的 IgG4-SC 具有挑战性。在这里，我们回顾了 IgG4-SC 的分类和诊断标准，特别关注 2020 年临床诊断标准和来自日本全国调查的大型 IgG4-SC 病例系列。诊断孤立的 IgG4-SC 或与 AIP 无关的 IgG4-SC 具有挑战性。在这里，我们回顾了 IgG4-SC 的分类和诊断标准，特别关注 2020 年临床诊断标准和来自日本全国调查的大型 IgG4-SC 病例系列。