Occult pancreaticobiliary reflux is a pathogenic factor of some benign biliary diseases and gallbladder cancer

Background:Pancreaticobiliary maljunction(PBM)is a well-known high-risk factor for biliary malignant tumors because of constant pancreaticobiliary reflux(PBR).However,the impact of occult pancreaticobiliary reflux(OPR),which is characterized by high bile amylase levels in individuals with anatomically normal pancreaticobiliary junction,on biliary diseases remains unclear.The aim of this study was to assess the correlation between OPR and biliary diseases.Methods:We enrolled 94 consecutive patients with normal pancreaticobiliary junction and primary biliary diseases confirmed by magnetic resonance cholangiopancreatography.We prospectively collected patients’bile samples and measured bile amylase levels.We investigated the incidence of OPR and the difference in bile amylase levels among these patients and assessed the correlation between high bile amylase levels(HBAL)and benign or malignant biliary diseases,as well as the OPR risk factors.Results:The incidence of OPR was 36.6%in patients with benign biliary diseases,26.7%in those with cholangiocarcinoma and 62.5%in those with gallbladder cancer.The median bile amylase level tended to be higher in patients with gallbladder cancer than in those with benign biliary diseases,but there was no significant difference(165.5 IU/L vs.23.0 IU/L,P=0.212).The prevalence of an HBAL with bile amylase levels of 1000-7500 IU/L was similar in patients with gallbladder cancer and benign biliary diseases.However,the incidence of HBAL with bile amylase levels greater than 7500 IU/L was significantly higher in patients with gallbladder cancer than in those with benign biliary diseases(37.5%vs.4.2%,P=0.012).Multivariate logistic regression analysis revealed that choledocholithiasis was an independent risk factor for OPR.Conclusions:OPR can occur in benign and malignant biliary diseases,and it may be a pathogenic factor for some benign biliary diseases and a high-risk factor for gallbladder cancer.There is a correlation between choledocholithiasis and OPR.

Western blotting in the diagnosis of duodenal-biliary and pancreaticobiliary refluxes in biliary diseases

BACKGROUND: Currently adopted diagnostic methods for duodenal-biliary and pancreaticobiliary refluxes carry many flaws, so the incidence of the two refluxes demands further larger sample size studies. This study aimed to evaluate Western blotting for the diagnosis of refluxes in biliary diseases. METHODS: An oral radionuclide (99)mTc-DTPA test (radionuclide, RN) was conducted for the observation of duodenal-biliary reflux prior to measuring bile radioactivity and Western blotting for detecting bile enterokinase (EK). Pancreaticobiliary reflux was assessed by biochemical and Western blotting tests for biliary amylase activity and trypsin-1, respectively. In accordance with bile sample origin, our samples were classified into ductal bile and gall bile groups; based on each individual biliary disease, we further classified the ductal bile group into five subgroups, and the gall bile group into four sub-groups. Western blotting was conducted to assess the two refluxes in biliary diseases. RESULTS: Consistencies were noted between EK and RN tests when diagnosing duodenal-biliary reflux (P<0.001). The amylase and trypsin-1 tests also showed consistency in diagnosing pancreaticobiliary reflux (P<0.001). Amylase and lipase levels within gall and ductal bile were strongly correlated (P<0.05). In the common bile duct pigment stone group, the EK and trypsin-1 positive rates were found to be insignificant (P>0.05); in the common bile duct cyst group, the EK positive rate was significantly lower than the trypsin-1 positive rate (P<0.05). CONCLUSIONS: Western blotting can accurately reflect duodenal-biliary and pancreaticobiliary refluxes. EK has greater sensitivity than RN for duodenal-biliary reflux. The majority of biliary amylase and lipase comes from the pancreas in all biliary diseases; pancreaticobiliary reflux is the predominant source in the common bile duct cyst group and duodenal-biliary reflux is responsible for the ductal pigment stone group.