This is a randomized, open-label, single-center clinical trial to compare the efficacy and safety profile for medium-dose versus high dose glucocorticoid in patients with IgG4-related Disease. Patients will be followed for three months to measure the primary outcome and secondary outcomes.

Inclusion Criteria:

• Males and females

• Age 18-70 years old with informed consent

• Patients with IgG4-RD:

  1. swelling, sclerosing and inflammatory involvement of one or more organ, including sclerosing pancreatitis, sclerosing cholangitis, inflammatory pseudotumors, retroperitoneal or mediastinal fibrosis, interstitial nephritis, hypophysitis, sclerosing dacryoadenitis, sialadenitis, inflammatory aortic aneurysm, lymphadenopathy, or other inflammatory conditions;
  2. elevated serum IgG4 (>1.35 g/L)
  3. histopathologic features of fibrosis and/or lymphocytic and polyclonal plasma cell infiltration (and IgG4+ plasma cells on immunohistology when performed);
  4. exclusion of other diseases.

Exclusion Criteria:

• Previously or currently received glucocorticoid and(or) immunomodulator
• Pregnancy or lactating
• Concurrent severe and/or uncontrolled and/or unstable diseases
• Patient with malignancy