Table 1

The HISORt criteria for the diagnosis of autoimmune pancreatitis2

1.Histopathology—one or both criteria requiredCharacteristic appearances within biopsy or resection material*
At least 10 IgG4-positive plasma cells per high power field within areas of lymphoplasmacytic infiltrate
2.Imaging and serology—all three criteria requiredDiffusely enlarged pancreas with delayed and ‘rim’ enhancement
Irregular attenuated pancreatic duct
Increased serum IgG4 concentration
Unexplained pancreatic disease after a full clinical workup—including exclusion of cancer
Raised serum IgG4 concentration and/or extrapancreatic organ involvement with increased numbers of tissue IgG4-positive plasma cells
3.Response to steroid therapy—all three criteria requiredResolution or marked improvement in disease with steroid therapy
  • *This includes a lymphoplasmacytic infiltrate, ‘storiform’ fibrosis and obliterative phlebitis; the inflammatory cell infiltrate alone is not sufficient to meet this criterion.