From the Guidelines
Antimitochondrial antibodies (AMA) are typically negative in primary sclerosing cholangitis (PSC), while antinuclear antibodies (ANA) are often positive, with approximately 30-80% of patients showing positivity, as reported in the 2019 British Society of Gastroenterology and UK-PSC guidelines for the diagnosis and management of primary sclerosing cholangitis 1.
Key Points
- Antimitochondrial antibodies are usually negative in PSC, which helps distinguish it from primary biliary cholangitis (PBC) where AMAs are characteristically positive in 90-95% of cases.
- Antinuclear antibodies (ANA) are often positive in PSC patients, but they lack diagnostic specificity for PSC.
- The presence of ANAs in PSC may indicate overlap with autoimmune hepatitis or suggest a more aggressive disease course in some patients.
- Other antibodies, such as p-ANCA (perinuclear anti-neutrophil cytoplasmic antibodies), are also found in PSC patients, with a reported positivity of 26-94% 1.
Diagnosis and Management
- The definitive diagnosis of PSC relies on characteristic cholangiographic findings of multifocal bile duct strictures and dilatations, along with compatible clinical, biochemical, and histological features.
- Antibody testing, including ANA and AMA, should be part of the initial workup for any patient with cholestatic liver disease to help distinguish between PSC, PBC, and potential overlap syndromes.
- Measurement of other biochemical tests, including smooth muscle antibodies (SMA), HIV antibodies, serum angiotensin converting enzyme, total immunoglobulins, and immunoglobulin subsets (including IgG4), should be performed to exclude secondary causes and alternative diagnoses 1.
From the Research
Antimitochondrial Antibodies and ANA in PSC
- Antimitochondrial antibodies (AMA) are typically associated with primary biliary cholangitis (PBC), not primary sclerosing cholangitis (PSC) 2
- There is limited information available on the role of AMA in PSC, as most studies focus on PBC or other autoimmune liver diseases
- ANA (antinuclear antibodies) can be present in various autoimmune diseases, including PSC, but their significance in PSC is not well understood 2
- The presence of ANA in PSC patients may indicate a higher risk of developing other autoimmune disorders or complications, but more research is needed to confirm this
PSC Diagnosis and Management
- PSC is a chronic, progressive liver disease characterized by inflammatory destruction of the bile ducts, leading to bile stasis, fibrosis, and cirrhosis 3, 4
- The diagnosis of PSC is typically made using a combination of imaging studies, liver function tests, and endoscopic retrograde cholangiopancreatography (ERCP) 4, 5
- Management of PSC is focused on treating symptoms, managing complications, and monitoring for disease progression and development of cholangiocarcinoma 3, 4, 5, 6
Autoimmune Associations
- PSC is often associated with inflammatory bowel disease (IBD), particularly ulcerative colitis 3, 4, 5, 6
- The presence of autoimmune antibodies, such as ANA, in PSC patients may indicate a higher risk of developing other autoimmune disorders or complications, but more research is needed to confirm this 2