ABSTRACT
Objective To investigate the value of serum IgG4 level for the diagnosis of IgG4-related hepatobiliary diseases and the differentiation from other hepatobiliary diseases.Methods A total of 270 patients with hepatobiliary diseases in the People's Hospital of Hunan Province from August 2015 to April 2017 were enrolled in this study,and 20 healthy subjects were selected as controls.The 270patients were divided into eight groups:liver cirrhosis group (n =17),acute pancreatitis group (n =52),chronic pancreatitis group (n =33),cholecystitis and gallstone group (n =27),bile duct carcinoma group (n =30),cholangitis and biliary calculi group (n =41),pancreatic cancer group (n =47),IgG4-related hepatobiliary disease group (n =23).The levels of serum IgG4 were measured by rate nephelometery assay.The sensitivity and specificity of IgG4 levels for distinguishing IgG4-associated hepatobiliary diseases were evaluated by receiver operating characteristic curve.Results The levels of IgG4 of the cirrhosis group and the IgG4 related hepatobiliary disease group were significantly higher than those of the control group (P ＜ 0.05).The IgG4 level in the hepatobiliary disease group was significantly higher than those of the other seven groups (Z =-5.267,-6.802,-5.921,-6.005,-6.173,-6.513,-6.014,P all ＜ 0.01).The area under curve (AUC) for IgG4 level in distinguishing IgG4 associated hepatobiliary diseases and other hepatobiliary diseases was 0.982.When 4.13 g/L was used as the cut off value of diagnosis,the sensitivity and specificity of IgG4for diagnosis were 95.7％ and 96.0％ respectively.The IgG4 levels in twelve patients with IgG-associated hepatobiliary diseases after 2 months of glucocorticoid therapy were significantly lower than those before glucocorticoid therapy (Z =-2.021,P =0.043).Conclusion The elevated serum IgG4 level may not be specific just for IgG4-related hepatobiliary diseases.The cut off value of 4.13 g/L should be very useful for diagnosing IgG4-related hepatobiliary diseases,differentiating from other hepatobiliary diseases and evaluating the therapeutic effect of glucocorticoid therapy.The further detailed verification for these findings should be necessary in clinical practice by increasing the sample size.