**4. Diagnosis**

#### **4.1 Clinical symptoms**

The clinical manifestation of AIP is variable and non-specific. The most frequent symptom is painless jaundice due to compression of intrapancreatic segment of choledochus by the fibroinflammatory process in the pancreatic head. Unfortunately, it shares typical symptoms of pancreatic head cancer and represents one of the most challenging difficulties in differential diagnosis. Abdominal pain and mild acute pancreatitis are also important manifestations. However, severe acute pancreatitis and major local fluid collections practically do not occur and autoimmunity is not a frequent cause of recurrent acute pancreatitis.
