date: “2024-01-01” title: Primary sclerosing cholangitis PSC alias: Primary sclerosing cholangitis
Primary sclerosing cholangitis (PSC)
(NEJM 2016;375:1161; Clin Liver Dis 2020;15:125)
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Diffuse inflammation of intrahepatic and extrahepatic bile ducts leading to fibrosis & stricturing of biliary system. A/w HLA-B8 and -DR3 or -DR4, frequent ⊕ autoantibodies.
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Epi:
- ♂ >♀ (20-50 y) ~70% Pts w/ PSC have IBD (usually UC);
- only 1-4% w/ UC have PSC. ⊕ prognostic factors: ♂, absence of IBD, small duct PSC (Gastro 2017;152:1829).
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Symptoms:
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Ddx:
- 👉 Extrahepatic cholestasis
- PBC
- overlap w/ AIH,
- IgG4 autoimmune cholangitis,
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Dx:
- cholangiography (MRCP ± ERCP) → multifocal beaded bile duct strictures
- exclude 2° cause
- 一種自身抗體,即核週抗中性粒細胞胞漿抗體 (pANCA),在約 65% 的 PSC 患者中呈陽性。
- 60% 至 80% 的 PSC 有潰瘍性結腸炎 (UC);因此,建議在診斷時進行結腸鏡檢查。
- may miss dx if confined to small intrahepatic ducts (“small duct PSC”).
- Liver bx if unclear: onion-skin fibrosis around bile ducts + some findings similar to PBC.