The investigators aimed to collect demographic features and clinical outcomes in patients diagnosed with PSC and IgG4-SC by utilizing participants database from multiple medical centers across Mainland China. Cross-sectional studies will focus on characterizing clinical presentations and validating diagnostic and prognostic models on Chinese PSC and IgG4-SC patients.

Inclusion Criteria:

• Age above 18 years old,
• Male or Female,
• Patients admitted in our medical centers which met the PSC criteria according to The European Association for the Study of the Liver Clinical Practice Guidelines "Management of cholestatic liver diseases" in 2009; or patients diagnosed with IgG4-SC which met initially using the Japan Pancreas Society criteria and confirmed using HISORt criteria.

Exclusion Criteria:

• Female subjects who is pregnant, breastfeeding or is considering being pregnant during the study;
• History of other malignancies, including hematological tumors, solid tumors except hepatobiliary system;
• History of infectious diseases, including hepatis A, B, C, E and tuberculosis.

This program will be conducted in multiple medical centers among the major cities across Mainland China. The sample size of subjects will be 1000, including 500 patients with PSC and 500 patients with IgG4-SC.

After this observational study is recruited, we are welcome to share the basic demographics and clinical outcomes of recruited IPD.