Abstract:Objective To explore the diagnosis and treatment and prognosis of IgG4-related autoimmune pancreatitis (AIP) . Methods A retrospective analysis was conducted on the clinical data of 9 patients with AIP admitted to Jilin Province FAW General Hospital from 2015 to 2023. The clinical manifestations, laboratory tests, imagingexaminations, and diagnosis and treatment processes of the patients were comprehensively analyzed. Results There were 9 AIP patients, including 3 males and 6 females. Six patients showed different degrees of liver function abnormalities, mainly elevated glutamyl transpeptidase (GGT) and alkaline phosphatase (ALP) , and some patients had elevated total bilirubin (TBIL) and direct bilirubin (DBIL) . Carbohgdrate antigen (CA) 199 was slightly elevated in 3 of the 9 patients, and serum IgG4 was elevated to different degrees in 9 patients, which was more than twice of the normal high value. Imaging examination suggested diffuse enlargement of the pancreas in 4 cases, presenting as a sausage.like change. Two cases showed localized enlargement of the caput pancreatis, with mild enhancement on contrast.enhanced scanning, and the degree of enhancement remained lower than that of normal pancreatic tissue. There were 3 cases of limited enlargement of the body part of the pancreas, and the enhancement scans suggesteddifferent degrees of enhancement. All 9 patients were treated with hormone therapy, with good therapeutic effects, and were followed up through outpatient or hospitalization until 2024, and there were 3 patients relapsed and were treated with hormone therapy again. Conclusion Serum IgG4 associated AIP is an autoimmune disease, and patients with localized pancreatic enlargement are prone to be misdiagnosed as pancreatic cancer. A comprehensive analysis of patients’clinical manifestations, laboratory examinations, imaging examinations, and hormone treatment effects will help to improve the diagnostic rate of this disease. Endoscopic biliary stent implantation can quickly alleviate discomfortcaused by moderate to severe jaundice.