Cholangiocarcinoma (CCA) presents significant diagnostic challenges, resulting in late patient diagnosis and poor survival rates. Primary sclerosing cholangitis (PSC) patients pose a particularly difficult clinical dilemma because they harbor chronic biliary strictures that are difficult to distinguish from CCA. MicroRNAs (miRs) have recently emerged as a valuable class of diagnostic markers; however, thus far, neither extracellular vesicles (EVs) nor miRs within EVs have been investigated in human bile. We aimed to comprehensively characterize human biliary EVs, including their miR content. We have established the presence of extracellular vesicles in human bile. In addition, we have demonstrated that human biliary EVs contain abundant miR species, which are stable and therefore amenable to the development of disease marker panels. Furthermore, we have characterized the protein content, size, numbers, and size distribution of human biliary EVs. Utilizing multivariate organization of combinatorial alterations (MOCA), we defined a novel biliary vesicle miR-based panel for CCA diagnosis that demonstrated a sensitivity of 67% and specificity of 96%. Importantly, our control group contained 13 PSC patients, 16 with biliary obstruction of varying etiologies (including benign biliary stricture, papillary stenosis, choledocholithiasis, extrinsic compression from pancreatic cysts, and cholangitis), and 3 with bile leak syndromes. Clinically, these types of patients present with a biliary obstructive clinical picture that could be confused with CCA. Conclusion: These findings establish the importance of using extracellular vesicles, rather than whole bile, for developing miR-based disease markers in bile. Finally, we report on the development of a novel bile-based CCA diagnostic panel that is stable, reproducible, and has potential clinical utility. (Hepatology 2014;60:896–907)

Less common etiologies of exocrine pancreatic insufficiency

The combination of prophylactic pancreatic stent placement (PSP) – a temporary plastic stent placed in the pancreatic duct – and rectal non-steroidal anti-inflammatory drugs (NSAIDs) is recommended for preventing post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) in high-risk cases. Preliminary data, however, suggest that PSP may be unnecessary if rectal NSAIDs are administered. Given the costs and potential risks of PSP, we aim to determine whether rectal indomethacin obviates the need for pancreatic stent placement in patients undergoing high-risk ERCP. The SVI (Stent vs. Indomethacin) trial is a comparative effectiveness, multicenter, randomized, double-blind, non-inferiority study of rectal indomethacin alone versus the combination of rectal indomethacin and PSP for preventing PEP in high-risk cases. One thousand four hundred and thirty subjects undergoing high-risk ERCP, in whom PSP is planned solely for PEP prevention, will be randomized to indomethacin alone or combination therapy. Those who are aware of study group assignment, including the endoscopist, will not be involved in the post-procedure care of the patient for at least 48 hours. Subjects will be assessed for PEP and its severity by a panel of independent and blinded adjudicators. Indomethacin alone will be declared non-inferior to combination therapy if the two-sided 95 % upper confidence bound of the treatment difference is less than 5 % between the two groups. Biological specimens will be obtained from trial participants and centrally banked. The SVI trial is designed to determine whether PSP remains necessary in the era of NSAIDs pharmacoprevention. The associated bio-repository will establish the groundwork for important scientific breakthrough. NCT02476279, registered June 2015.

Summary: Background: The efficacy of many pharmacological agents for preventing post‐ERCP pancreatitis (PEP) has been evaluated in randomised controlled trials (RCTs), but it is unclear which agent(s) should be used in clinical practice. Network meta‐analyses of RCTs are used to simultaneously compare several agents to determine their relative efficacy and identify priority agents for comparison in future RCTs.Aim: To evaluate pharmacological agents for the prevention of PEP by conducting a network meta‐analysis of RCTs.Methods: We searched MEDLINE, EMBASE and Cochrane Library databases for RCTs that evaluated the efficacy of agents for preventing PEP. RCTs were simultaneously analysed using random‐effects network meta‐analysis under the Bayesian framework to identify the best agents. The efficacy of agents was ordered according to the probability of being ranked as any of the top three best performing agents.Results: The network meta‐analysis included 99 RCTs evaluating 16 agents in 25 313 patients. Topical epinephrine (adrenaline) was the most efficacious agent with 85.9% probability of ranking among the top three agents, followed by nafamostat (51.4%), antibiotics (44.5%) and NSAIDs (42.8%). However, in a sensitivity analysis including only rectal NSAIDs, NSAIDs moved from fourth rank to second (58.1%). Patients receiving topical epinephrine, compared with placebo, had a 75% reduced risk of PEP (OR 0.25, 95% probability interval 0.06–0.66).Conclusions: Topical epinephrine and rectal NSAIDs are the most efficacious agents for preventing post‐ERCP pancreatitis, based on existing RCTs. Combinations of these agents, which act on different steps in the pathogenesis of post‐ERCP pancreatitis, should be evaluated in future trials.