TABLE 1.

HISORt diagnostic criteria for autoimmune pancreatitis (AIP) and immunoglobulin G4 (IgG4)-associated cholangitis (IAC)

AIP	IAC
Histology Plasmacytic infiltrate with =10 IgG4-positive cells cells/HPF Periductal infiltrate with obliterative phlebitis and storiform fibrosis	Histology Plasmacytic sclerosing cholangitis with =10 IgG4-positive cells/HPF Obliterative phlebitis and storiform fibrosis
Imaging Diffusely enlarged pancreas with delayed (rim) enhancement with irregular, attenuated main pancreatic duct Variants with focal pancreatic mass, focal pancreatic duct stricture, pancreatic atrophy, pancreatic calcification or pancreatitis	Imaging Strictures involving intrahepatic, proximal extrahepatic or intrapancreatic bile ducts Fleeting/migrating biliary strictures
Serology Elevated serum IgG4 level (>140 g/L)	Serology Elevated serum IgG4 level (>140 g/L)
Other organ involvement Hilar, intrahepatic or distal biliary strictures Parotid and lacrimal gland Mediastinal lymphadenopathy Retroperitoneal fibrosis	Other organ involvement Features of AIP on imaging or histology Retroperitoneal fibrosis Renal lesions Salivary/lacrimal gland enlargement
Response to steroid therapy Resolution or marked improvement of pancreatic and extrapancreatic manifestations	Response to steroid therapy Normalization of liver enzyme levels or resolution of biliary stricture

HISORt Histology, imaging, serology, organ involvement and response to steroid therapy; HPF High-power field. Adapted with permission from reference 43