Epidemiology

  • Sex: ♂ > ♀ (2:1)
  • Age: The median age at diagnosis is ∼ 40.

Tip

Compared with Primary biliary cholangitis, which are common among middle-aged women.


Etiology

  • The exact cause is unknown.
  • Associations
    • Chronic inflammatory bowel diseases (IBD)
      • ∼ 90% of patients with PSC have IBD (approx. 87% of these patients have ulcerative colitis)
    • Presence of HLA-B8 and HLA-DR3

The majority of patients with PSC also have


Pathophysiology

Progressive chronic inflammation of both intrahepatic and extrahepatic bile ducts


Clinical features

  • Signs of cholestasis
    • Jaundice/scleral icterus
    • Pruritus
    • Pale stool, dark urine
    • Fatigue
    • Can lead to acute cholangitis (fever, chills, right upper quadrant pain)
  • Later stages: signs of cirrhosis
    • Hepatosplenomegaly
    • Portal hypertension
    • Liver failure
  • Symptoms of chronic inflammatory bowel disease, which is frequently associated with PSC, or other associated comorbidities

Diagnostics

Autoimmune Liver Diseases

FeaturePrimary Sclerosing Cholangitis (PSC)Primary Biliary Cholangitis (PBC)Autoimmune Hepatitis (AIH)
PathoInflammation/fibrosis of intra- & extrahepatic bile ductsAutoimmune destruction of intrahepatic bile ductsAutoimmune destruction of hepatocytes
Epi / Assoc.M > F (2:1), <40s
Assoc: Ulcerative Colitis (IBD) (>80%)
F >> M (9:1), 40-60s
Assoc: Sjögren’s, other autoimmune dz
F > M (3:1), bimodal (young/middle-aged)
Assoc: Other autoimmune dz
LabsCholestatic: ↑↑ ALP, ↑ GGTCholestatic: ↑↑ ALP, ↑ GGTHepatocellular: ↑↑↑ AST/ALT (>1000s common), ↑ IgG
Serology(+) p-ANCA(+) AMA (Anti-Mitochondrial Ab)(+) ANA, (+) ASMA (Anti-Smooth Muscle Ab)
Dx / HistoMRCP/ERCP: “Beads on a string”
Histo: “Onion skinning” periductal fibrosis
Normal imaging
Histo: Florid duct lesion (lymphocytic cholangitis, granulomas)
Normal/nonspecific imaging
Histo: Interface hepatitis, plasma cells
TxSymptomatic Tx; Liver transplant (definitive)Ursodeoxycholic acid (UDCA)Corticosteroids, Azathioprine
Key RiskCholangiocarcinoma, Colorectal Cancer (w/ UC)Osteoporosis, Cirrhosis, HCCCirrhosis, Acute Liver Failure

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  • Cholestatic enzymes
    • ALP
    • ↑ GGT
    • Normal or ↑ conjugated bilirubin
  • Transaminases: normal or moderately elevated (approx. 2–3× ULN) AST and ALT
  • Lipid profile: ↑ total cholesterol

Mnemonic

Suspect PSC in patients with a history of inflammatory bowel disease and elevated cholestatic enzymes (ALP, GGT, and conjugated bilirubin).

  • Typical perinuclear anti-neutrophil cytoplasmic antibodies (pANCA): present in up to 80% of patients with PSC.

Magnetic resonance cholangiopancreatography

  • Method of choice (if there is no biliary obstruction)
  • Supportive findings: multifocal intrahepatic and extrahepatic bile duct strictures alternating with dilatation and beading of bile ductsThere is irregular dilatation (green overlay) of intrahepatic bile ducts proximal to a common duct stenosis (arrow). Alternation of strictured and dilated segments creates a beaded appearance. Peripheral ducts appear pruned as a result of obliteration (examples indicated by arrowheads), and scattered biliary diverticula are seen (example indicated by red overlay).

Differential Diagnosis


Treatment


Complications

  • Cholangiocarcinoma (∼ 10–15% of cases)