IgG4-related disease (IgG4-RD) is a multi-systemic disorder.
IgG4-related sclerosing cholangitis (IgG4-SC) is the biliary manifestation of the disease, often in association with autoimmune pancreatitis (AIP).
Hepatic manifestations of IgG4-RD are less well described within the literature.
Drs Joshi and Webster from the United Kingdom examined and presented an overview of IgG4-RD with a focus on the biliary and hepatic manifestations.
An electronic search using Medline was performed.
Search items included ‘IgG4 multi-system disease, IgG4 associated cholangitis, IgG4 associated liver disease and autoimmune pancreatitis’.
The team characterized IgG4-RD by an IgG4-positive lymphoplasmacytic tissue infiltrate, storiform fibrosis and an obliterative phlebitis.
|Patients with relapsing disease or multifocal disease should be considered for azathioprine|
|Alimentary Pharmacology & Therapeutics|
The HISORt criteria may be used to establish the diagnosis and incorporate a multi-disciplinary approach involving histology, radiology, serum IgG4 levels and response to steroid therapy.
The research team noted that IgG4-SC is the commonest extrapancreatic manifestation of type-1 AIP, while the hepatic manifestations remain poorly defined.
Important differential diagnoses include primary sclerosing cholangitis, secondary sclerosing cholangitis, cholangiocarcinoma and pancreatic carcinoma.
The team report that current treatment regimens remain ill defined although steroid therapy is used first line unless contraindicated.
The researchers recommend that patients with relapsing disease or multifocal disease should be considered for azathioprine.
Available data would also suggest a role for rituximab.
Dr Webster and colleague conclude, "IgG4-related sclerosing cholangitis is a common manifestation of IgG4-related disease which requires a multi-disciplinary approach to establish the diagnosis."
"Differentiating IgG4-related sclerosing cholangitis from other conditions, both benign and malignant, is challenging, but vital."
"Steroids remain the mainstay of treatment."
"Our understanding of the pathogenesis of the hepatic manifestations of IgG4-related disease continues to evolve."