The immunoglobulin level, which is specifically elevated in autoimmune pancreatitis is which of the following?
Serum IgG4 is elevated at least twofold higher than 135 mg/dL in those with autoimmune pancreatitis. Reference: Harrisons Principles of Internal Medicine, 18th Edition, Page 2644
IgM
IgE
IgG4
IgG2