1st order laboratory parameters – obligatory laboratory tests.
- Cholestasis parameters (elevated)
- [Only mild transaminase elevation; elevated AP (alkaline phosphatase) (3- to 10-fold) is often suggestive; GGT (gamma-GT) is often normal or discretely elevated]Note: Wg. fluctuations of the AP in the course, even a normal-value AP can not exclude a primary sclerosing cholangitis (PSC)!
- Bilirubin may be elevated (in 50% of cases; increases only with increase in destruction of the biliary system). Note: No meaningful conclusions can be drawn from the level of serum bilirubin.
- A high AP compared with bilirubin usually indicates infiltrative processes. Usually LDH (lactate dehydrogenase) also increases].
- Detection of ANA (antinuclear antibodies) and ANCA (antineutrophil cytoplasmic antibodies) with perinuclear fluorescence pattern (pANCA) [positive: 60% of cases].
- Liver puncture (liver biopsy; tissue removal from the liver; examination method for the investigation of diffuse or circumscribed liver changes); [in PSC shows:
- Periductal fibrosis (“around a duct” occurring pathological proliferation of connective tissue); the intrahepatic (located within the liver) bile ducts are affected
- Inflammatory infiltrates
- Biliary proliferates (formation of new bile ducts)]
- Serum copper (elevated)
Note: Primary sclerosing cholangitis-specific auto-Ak are not known.
Laboratory parameters 2nd order – depending on the results of the history, physical examination, etc. – for differential diagnostic clarification.
- Carbohydrate antigen (CA) 19-9 – tumor marker for cholangiocellular carcinoma (CCC; bile duct cancer); annual (according to EASL and AASLD recommendations).