Age and incidence of occult pancreaticobiliary reflux in patients with benign gallbladder diseases.

BACKGROUND: Occult pancreaticobiliary reflux (OPBR) has a significant correlation with diseases of the gallbladder and biliary system. This study examined the incidence of OPBR by age in patients with benign gallbladder diseases. METHODS: We assessed 475 patients with benign gallbladder diseases who underwent surgery at Shanghai East Hospital from December 2020 to December 2021. Bile samples collected during surgery were tested for amylase. Patients with bile amylase >110 U/L (n = 64) were classified as the OPBR group; the rest (n = 411) as controls. RESULTS: Of the participants, 375 had gallbladder stone (GS), 170 had gallbladder polyp (GP), and 49 had gallbladder adenomyomatosis (GA). The OPBR group was generally older, with OPBR incidence increasing with age, peaking post-45. Rates by age were: 4.9% (<35), 5.2% (35-44), 20.7% (45-54), 22.5% (55-64) and 17.6% (≥65), mainly in GS patients. ROC analysis for predicting OPBR by age yielded an area under the curve of 0.656, optimal cut-off at 45 years. Logistic regression indicated age > 45, GP, male gender, and BMI ≥ 24 kg*m-2 as independent OPBR predictors in GS patients. Based on these variables, a predictive nomogram was constructed, and its effectiveness was validated using the ROC curve, calibration curve and decision curve analysis (DCA). Further stratification revealed that among GS patients ≤ 45, concurrent GA was an OPBR risk; for > 45, it was GP and male gender. CONCLUSIONS: The incidence of OPBR in GS patients is notably influenced by age, with those over 45, especially males without GP, being at heightened risk.

Identification of changes in bile composition in pancreaticobiliary reflux based on liquid chromatography/mass spectrometry metabolomics.

INTRODUCTION: Pancreaticobiliary reflux (PBR) can induce gallstone formation; however, its pathogenic mechanism remains unclear. In this study, we explored the mechanism of PBR by the non-targeted metabolomic analysis of bile in patients with PBR. OBJECTIVE: The aim of this study was to investigate the pathogenic mechanism in PBR by the non-targeted metabolomic analysis of bile collected during surgery. METHODS: Sixty patients who underwent gallstone surgery at our center from December 2020 to May 2021 were enrolled in the study. According to the level of bile amylase, 30 patients with increased bile amylase ( > 110 U/L) were classified into the PBR group, and the remaining 30 patients were classified into the control group (≤ 110 U/L). The metabolomic analysis of bile was performed. RESULTS: The orthogonal projections to latent structure-discriminant analysis of liquid chromatography mass spectrometry showed significant differences in bile components between the PBR and control groups, and 40 metabolites were screened by variable importance for the projection value (VIP > 1). The levels of phosphatidylcholine (PC) and PC (20:3(8Z,11Z,14Z)/14:0) decreased significantly, whereas the levels of lysoPC (16:1(9z)/0:0), lysoPC (15:0), lysoPC (16:0), palmitic acid, arachidonic acid, leucine, methionine, L-tyrosine, and phenylalanine increased. CONCLUSIONS: Significant differences in bile metabolites were observed between the PBR and control groups. Changes in amino acids and lipid metabolites may be related to stone formation and mucosal inflammation.

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.

Free fatty acids and triglyceride change in the gallbladder bile of gallstone patients with pancreaticobiliary reflux.

BACKGROUND: Pancreaticobiliary reflux (PBR) causes chronic inflammation of the gallbladder mucosa and changes in the bile components, which are known to promote gallstone formation. This study aimed to investigate the bile biochemistry changes in gallstone patients with PBR and provide new clues for research on the involvement of PBR in gallstone formation. METHODS: Patients undergoing surgery for gallstones between December 2020 and May 2021 were eligible for inclusion. The bile biochemistry (including amylase, lipase, triglyceride, cholesterol, free fatty acids [FFAs], alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [ALP], and γ-glutamyl transferase [γ-GT]) of the included gallstone patients was analysed to determine correlations with PBR. RESULTS: In this study, 144 gallstone patients who underwent surgery were enrolled. Overall, 15.97 % of the patients had an increased bile amylase level, which was associated with older age and significantly higher bile levels of ALP, lipase, triglyceride, and FFAs. Positive correlations were observed between amylase and lipase, triglyceride, FFAs levels in the gallbladder bile. However, the bile levels of triglyceride, FFAs, and lipase were positively correlated with each other only in the PBR group and showed no significant correlation in the control (N) group. In addition, elevated bile FFAs levels were found to be an independent risk factor for gallbladder wall thickening. CONCLUSIONS: In conclusion, PBR-induced increase in FFAs and triglyceride in the gallbladder bile is a cause of gallstone formation, and an increase in bile ALP suggests the presence of cholestasis in PBR.

Pancreatobiliary reflux increases macrophage-secreted IL-8 and activates the PI3K/NFκB pathway to promote cholangiocarcinoma progression.

BACKGROUND: Persistent pancreaticobiliary reflux (PBR) is associated with a high risk of biliary malignancy. This study aimed to evaluate the proportion of PBR in biliary tract diseases and mechanisms by which PBR promoted cholangiocarcinoma progression. METHODS: Overall 227 consecutive patients with primary biliary tract disease participated in this study. The amylase levels in the collected bile were analyzed. The mechanisms underlying the effect of high-amylase bile on bile duct epithelial and cholangiocarcinoma cells progression were analyzed. The source of interleukin-8 (IL-8) and its effects on the biological functions of cholangiocarcinoma cells were investigated. RESULTS: The bile amylase levels in 148 of 227 patients were higher than the upper serum amylase limit of 135 IU/L. PBR was significantly correlated with sex, pyrexia, and serum gamma-glutamyl transferase (GGT) levels in the patient cohort. High-amylase bile-induced DNA damage and genetic differences in the transcript levels of the gallbladder mucosa and facilitated the proliferation and migration of bile duct cancer cells (HUCCT1 and QBC939 cells). The concentration of many cytokines increased in high-amylase bile. IL-8 is secreted primarily by macrophages via the mitogen-activated protein kinase pathway and partially by bile duct epithelial cells. IL-8 promotes the progression of HUCCT1 and QBC939 cells by regulating the expression of epithelial-mesenchymal transition-associated proteins and activating the phosphatidylinositol 3-kinase/nuclear factor kappa-B pathway. CONCLUSIONS: PBR is one of the primary causes of biliary disease. IL-8 secreted by macrophages or bile duct epithelial cells stimulated by high-amylase bile promotes cholangiocarcinoma progression.

Comparison of Slab and Pencil Beam Labeling in Spin-labeled MR Imaging for Pancreatic Juice Flow Visualization.

The usefulness of a highly targeted pencil beam (PB) label was compared with the commonly used slab label for direct visualization of pancreaticobiliary reflux using the time-spatial labeling inversion pulse (time-SLIP) technique. Signal profiles of flow phantom images obtained with a 1.5T MRI were analyzed. Both labels had similar labeling capabilities, but the edge characteristics of the PB label were blunt. Next, sixty-eight patients were classified into two groups according to the angle of the pancreaticobiliary ducts, and the displacement of the pancreatic ducts in respiratory fluctuation was measured. The results were approximately 7 mm in both groups. The blunt edge characteristics of the PB label suggest that it is robust to respiratory fluctuations. The overall labeling ability of the PB is comparable to that of the slab. In the larger angle of pancreaticobiliary ducts, the PB label may be able to label the pancreatic duct more selectively.

Gallbladder mucosal lesions associated with high biliary amylase irrespective of pancreaticobiliary maljunction.

BACKGROUND: Previous studies have focused on the presence of reflux in selected cohorts with pancreaticobiliary maljunction (PBM), but little is known regarding the wider incidence of occult reflux and associated mucosal changes. We aimed to correlate gallbladder mucosal abnormalities with objective evidence of PBM and occult pancreaticobiliary reflux (PBR) in an Australian population undergoing cholecystectomy. METHODS: Patients undergoing cholecystectomy between September 2010 and September 2012 were eligible for inclusion. Demographic and pre-operative clinical data were collated and entered into a pre-defined database. Operative cholangiograms were routinely performed and the presence of PBM noted. Gallbladder bile samples were analysed for bilirubin (<20 µmol/L), amylase (<100 U/L) and lipase (<70 U/L) levels. Evidence of PBR was correlated with gallbladder mucosal findings. RESULTS: A total of 305 cholecystectomies were performed for biliary colic (73%), choledocholithiasis (9%), cholecystitis (8.4%) and pancreatitis (6.4%). A total of 12.7% had cholangiographic evidence of PBM and 11.9% possessed gallbladder mucosal changes. Overall, 7.7% had increased biliary amylase, which was associated with significantly higher rates of gallbladder intestinal metaplasia (33% versus 8.6%; P = 0.012). Elevated biliary amylase was also higher in patients with prior pancreatitis (P = 0.02) or choledocholithiasis (P < 0.01). The presence of PBM did not predict for the presence of PBR. CONCLUSION: PBR is associated with an increased frequency of gallbladder mucosal metaplasia, irrespective of the presence of PBM. Objectively identified reflux represents an additional indication for cholecystectomy but the long-term consequences for extra-hepatic biliary malignancy remain unknown and warrant further investigation. Methods of objectively identifying PBR pre-operatively require further investigation.

Elevated bile amylase level without pancreaticobiliary maljunction is a risk factor for gallbladder carcinoma.

BACKGROUND: Elevated bile amylase level in patients with pancreaticobiliary maljunction (PBM) or high confluence of pancreaticobiliary ducts (HCPBD) is well known as a risk factor for gallbladder carcinoma (GBC) development. However, the effects of occult pancreaticobiliary reflux (OPR), a condition characterized by high bile amylase level in the presence of an anatomically normal pancreaticobiliary junction, on GBC development remain unclear. The aim of this study was to assess the relationship between OPR and GBC. METHODS: Clinicopathological data of 52 patients who were preoperatively diagnosed with gallbladder (GB) tumor (22 malignant, 30 benign) were retrospectively reviewed. All of the patients underwent preoperative endoscopic retrograde cholangiopancreatography to evaluate pancreaticobiliary junction morphology and bile amylase level. The relationship between the histological diagnosis of GB lesions, and pancreaticobiliary junction morphology and bile amylase level were investigated. RESULTS: Pancreaticobiliary maljunction, HCPBD, and normal pancreaticobiliary junction (NPJ) were identified in 12, nine, and 31 patients, respectively. The rates of GBC in patients with PBM, HCPBD, and NPJ were 58% (7/12), 67% (6/9), and 29% (9/31), respectively. Of the 31 patients with NPJ, 22 had OPR and nine of these had GBC. None of the patients with NPJ and normal bile amylase level had GBC. Additionally, among patients with NPJ, bile amylase level was significantly higher in patients with GBC than in patients with benign tumors. CONCLUSIONS: Occult pancreaticobiliary reflux, like PBM and HCPBD, is a risk factor for GBC development.

Long-term follow-up may be needed for pancreaticobiliary reflux in healthy adults.

PURPOSE: The reflux of pancreatic enzymes into the biliary tract is associated with chronic inflammation and increases cellular proliferation of the biliary epithelium, leading to biliary carcinoma. The aim of this study is to detect the incidence of occult pancreaticobiliary reflux (OPBR) in patients who underwent elective cholecystectomy. METHODS: Forty-seven patients with symptomatic gallstones who underwent cholecystectomy were recruited for this study. The gallbladder bile samples were obtained from the specimen of gallbladder and the amylase level was measured. The immunohistochemistry of p53, SMAD4 and Ki-67 were performed for the detection of metaplasia and dysplasia. RESULTS: Biliary amylase was higher than the serum amylase in 10 patients (group A, 15,402.66 ± 33,592.43 IU/L; group B, 13.06 ± 18.12 IU/L). The mean age was 67.2 years in group A and 51.2 in group B (P < 0.01). The ratio of male to female was 1:2.3 and 1:1.8 in group A and B, respectively (P = 0.297). Eight patients in group A and thirteen patients in group B had inflammation (P = 0.014). The positive results of the Ki-67 test were exhibited in five cases in each group (P = 0.024). CONCLUSION: Results from the study indicate that the age was older, degree of inflammation and positive rate of Ki-67 were higher when OPBR was suspected. In conclusion, the patients with OPBR would need long-term follow-up, because the OPBR can cause dysplasia and the reflux of pancreatic juice may be considered as a risk factor for extrahepatic bile duct carcinoma.

Pancreaticobiliary reflux in patients with a normal pancreaticobiliary junction: Pathologic implications.

Knowledge on pancreaticobiliary reflux in normal pancreaticobiliary junction and its pathologic implications has experienced tremendous progress during the last few years. This editorial reviews the current knowledge on this condition and its pathological implications on gallbladder diseases. The following aspects were defined appropriate for discussion: (1) Evidence of carcinogenesis associated with pancreaticobiliary reflux; (2) Evidence of pancreaticobiliary reflux in normal pancreaticobiliary junction; and (3) Evidence of sphincter of Oddi (SO) dysfunction as a cause of pancreaticobiliary reflux in normal pancreaticobiliary junction. The articles reviewed were selected and classified according to five levels of evidence: Level I, meta-analysis double-blind randomized clinical trials, Level II, cohort non-blinded studies and non-randomized clinical trials, Level III, good quality case-control studies and non-randomized cohort studies, Level IV, case series and poor quality case-control studies, and Level V, case report articles and experts' opinion. Evidence levels II, III, IV and V were found to support biliary carcinogenesis associated with pancreaticobiliary reflux in normal and abnormal pancreaticobiliary junction. The same levels of evidence were found to support the common occurrence of pancreaticobiliary reflux in normal pancreaticobiliary junction, and SO dysfunction as the most plausible cause of this condition. Although an important body of research has been published regarding pancreaticobiliary reflux in normal pancreaticobiliary junction and its clinical significance, the current evidence does not fully support what has been suggested. Studies with evidence level I have not been undertaken. This is a fascinating subject of study, and if finally supported by evidence level I, the importance of this condition will constitute a major breakthrough in biliary pathology.

Reflujo pancreáticobiliar en pacientes con colelitiasis y sin colelitiasis: estudio comparativo / Pancreaticobiliary reflux in patients with cholelithiasis and without cholelithiasis: a comparative study

Background. Pancreaticobiliary reflux is a pathologic phenomenon occurring in patients with gallstones. However, the occurrence of pancreaticobiliary reflux has not been studied in patients without gallstones. The objective of this study was to measure the bile levels of amylase and lipase in patients without gallstones submitted to cholecystectomy as part of another surgical procedure, and to compare these values with patients submitted to cholecystectomy for gallstone disease. Patients and Methods. A prospective observational comparative study was designed. A sample of 136 consecutive patients was included. Amylase and lipase levels were measured in bile. Normal serum amylase levels at our institution are 28-100 U/L and for lipase are 13-60 U/L. There are no established normal levels for pancreatic enzymes in bile. However, we considered elevated the bile amylase and lipase levels whenever they were higher than normal plasma levels. Results. One-hundred three patients (76 percent) had gallstones and 33 (24 percent) liad healthy gallbladders without gallstones. According to normal plasma levels for amylase and lipase, these enzymes in bile were elevated in 83.5 percent patients with gallstones, compared to elevated levels of amylase in 6 percent patients and lipase in 3 percent patients without gallstones. Conclusions. Pancreaticobiliary reflux is a common phenomenon in patients with gallstones and occurs sporadically in patients without gallstones.

Introducción. El reflujo pancreáticobiliar es un fenómeno patológico que ocurre en pacientes con colelitiasis. La ocurrencia de este fenómeno no ha sido estudiada en pacientes sin colelitiasis. El presente estudio tiene por objetivo medir los niveles de amilasa y lipasa en la bilis de pacientes sin colelitiasis, colecistectomizados como parte de otro procedimiento quirúrgico y comparar estos valores con pacientes colecistectomizados por colelitiasis. Pacientes y Métodos. Se diseñó un estudio observacional y comparativo. Una muestra de 136 pacientes consecutivos fue incluida. Se midieron los niveles de amilasa y lipasa en la bilis. En nuestra institución los valores normales para amilasa son 28-100 U/L y para lipasa 13-60 U/L. No se han establecido valores normales de enzimas pancreáticas en la bilis. Para efectos del presente estudio, se consideró como elevados los niveles biliares de amilasa y lipasa cuando fueron mayores a los valores plasmáticos normales. Resultados. 103 pacientes (76 por ciento) tenían colelitiasis y 33 (24 por ciento) tenían vesículas normales sin cálculos. De acuerdo a los valores plasmáticos normales de amilasa y lipasa, estas enzimas se encontraron elevadas en 83,5 por ciento de los pacientes con colelitiasis comparados con valores elevados de amilasa en 6 por ciento en pacientes sin colelitiasis y de lipasa en 3 por ciento de estos pacientes. Conclusiones. El reflujo pancreaticobiliar es un fenómeno común en pacientes con colelitiasis y ocurre esporádicamente en pacientes sin colelitiasis.