[The clinical characteristics of 32 patients with autoimmune pancreatitis]

To explore the clinical characteristics and diagnosis of autoimmune pancreatitis (AIP) with the aim to raise awareness of AIP.

Clinical data of 32 patients with AIP were retrospectively analyzed, including clinical manifestations, imaging features, laboratory examination, histopathology and treatment from November 2009 to April 2013 in the First Affiliated Hospital of Medical School, Zhejiang University.

All 32 AIP patients including 25 males and 7 females had a median age of (62.5 ± 12.6) years (27-84 years). The initial symptoms included obstructive jaundice in 50.0% patients (16/32), abdominal pain in 43.8% (14/32), fatigue and weight loss in 12.5% (4/32), and bloody stool in 6.3% (2/32). Laboratory findings revealed abnormal liver function in 6.3% (2/32) patients, increased immunoglobulins in 71.9% (23/32) patients and elevated IgG4 in 8/10 patients. Computerized tomography (CT) scan and ultrasonography were performed in all patients. Diffusely enlarged pancreas were found in 62.5% (20/32) patients and focally enlarged in 37.5% (12/32), additionally main pancreatic duct stenosis in 62.5% (20/32) patients. Nineteen patients obtained histopathological examination, indicating pancreatic interstitial fibrosis, and infiltration of lymphocytes and plasma cells.

Autoimmune pancreatitis is an autoimmune disease which may be misdiagnosed as pancreatic cancer. The clinical features, laboratory findings, imaging characteristics, and typical histopathologic presentation, as well as good response to glucocorticoids provide supportive evidence for the diagnosis of AIP.