Nafamostat mesylate in the prevention of post-ERCP pancreatitis and risk factors for post-ERCP pancreatitis

Pancreas-directed AAV8-hSPINK1 gene therapy safely and effectively protects against pancreatitis in mice

OBJECTIVE

Currently, there is no cure for chronic pancreatitis (CP). Germline loss-of-function variants in SPINK1 (encoding trypsin inhibitor) are common in patients with CP and are associated with acute attacks and progression of the disease. This preclinical study was conducted to explore the potential of adeno-associated virus type 8 (AAV8)-mediated overexpression of human SPINK1 (hSPINK1) for pancreatitis therapy in mice.

DESIGN

A capsid-optimised AAV8-mediated hSPINK1 expression vector (AAV8-hSPINK1) to target the pancreas was constructed. Mice were treated with AAV8-hSPINK1 by intraperitoneal injection. Pancreatic transduction efficiency and safety of AAV8-hSPINK1 were dynamically evaluated in infected mice. The effectiveness of AAV8-hSPINK1 on pancreatitis prevention and treatment was studied in three mouse models (caerulein-induced pancreatitis, pancreatic duct ligation and Spink1 c.194+2T>C mouse models).

RESULTS

The constructed AAV8-hSPINK1 vector specifically and safely targeted the pancreas, had low organ tropism for the heart, lungs, spleen, liver and kidneys and had a high transduction efficiency (the optimal expression dose was 2×1011 vg/animal). The expression and efficacy of hSPINK1 peaked at 4 weeks after injection and remained at significant level for up to at least 8 weeks. In all three mouse models, a single dose of AAV8-hSPINK1 before disease onset significantly alleviated the severity of pancreatitis, reduced the progression of fibrosis, decreased the levels of apoptosis and autophagy in the pancreas and accelerated the pancreatitis recovery process.

CONCLUSION

One-time injection of AAV8-hSPINK1 safely targets the pancreas with high transduction efficiency and effectively ameliorates pancreatitis phenotypes in mice. This approach is promising for the prevention and treatment of CP.

Effectiveness of the pharmacological therapy to prevent post ERCP acute pancreatitis: a network meta-analysis

OBJECTIVE

To determine the effectiveness of the different pharmacological agents in preventing post-ERCP acute pancreatitis.

METHODS

We included clinical trials of pharmacological interventions for prophylaxis of acute post-ERCP pancreatitis. The event evaluated was acute pancreatitis. We conducted a search strategy in MEDLINE (OVID), EMBASE, and Cochrane Central Register of Controlled Trials from inception to nowadays. We reported the information in terms of relative risks (RR) with a 95% confidence interval. We assessed the heterogeneity using the I2 test.

RESULTS

We included 84 studies for analysis (30,463 patients). The mean age was 59.3 years (SD ± 7.01). Heterogeneity between studies was low (I2 = 34.4%) with no inconsistencies (p = 0.2567). Post ERCP pancreatitis was less in prophylaxis with NSAIDs (RR 0.65 95% CI [0.52 to 0.80]), aggressive hydration with Lactate Ringer (RR 0.32 95% CI [0.12-0.86]), NSAIDs + isosorbide dinitrate (RR 0.28 95% CI [0.11-0.71]) and somatostatin and analogues (RR 0.54 [0.43 to 0.68]) compared with placebo.

CONCLUSIONS

NSAIDs, the Combination of NSAIDs + isosorbide dinitrate, somatostatin and analogues, and aggressive hydration with lactate ringer are pharmacological strategies that can prevent post-ERCP pancreatitis when compared to placebo. More clinical trials are required to determine the effectiveness of these drugs.

Nafamostat Reduces the Incidence of post-ERCP Pancreatitis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). As the management of pancreatitis is limited, clinical approaches focus on the prevention of post-ERCP pancreatitis (PEP). In theory, the serine protease inhibitor nafamostat can reduce circulating inflammatory mediators in pancreatitis. We aimed to investigate the effect of nafamostat in the prevention of PEP in this systematic review and meta-analysis. The protocol for this review was registered in PROSPERO (CRD42022367988). We systematically searched 5 databases without any filters on September 26, 2022. The eligible population was adult patients undergoing ERCP. We compared the PEP preventive effect of nafamostat to placebo. The main outcome was the occurrence of PEP. We calculated the pooled odds ratios (ORs), mean differences, and corresponding 95% confidence intervals (95% CIs) and multilevel model. The risk of bias was assessed using the Rob2 tool. Seven randomized controlled trials involving 2,962 patients were eligible for inclusion. Nafamostat reduced the overall incidence rate of PEP (20 mg, OR: 0.50, 95% CI: 0.30-0.82 and 50 mg, OR: 0.48, 95% CI: 0.24-0.96). However, the occurrence of mild PEP was significantly reduced only in the subgroup receiving 20 mg nafamostat (OR, 0.49, 95% CI: 0.31-0.77). Overall, nafamostat therapy reduced moderate PEP in high-risk patients (OR: 0.18, 95% CI: 0.0.4-0.84) and mild PEP in low-risk patients (OR: 0.32, 95% CI: 0.17-0.61). Nafamostat is an effective therapy in the prevention of mild post-ERCP pancreatitis. Further research is required to determine the cost-effectiveness of this therapy.

Efficacy of nafamostat mesylate in the prevention of pancreatitis after endoscopic retrograde cholangiopancreatography: a systematic review and meta-analysis of randomized controlled trials

We conducted a systematic review and meta-analysis to evaluate the effect of nafamostat on the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). PubMed, Web of Science, and Ichushi Web were searched for randomized controlled trials (RCTs) using nafamostat to prevent PEP. In subgroup analyses, we studied the preventive effects of nafamostat according to the severity of PEP, risk category, and dose. A random-effects model was adopted; heterogeneity between studies was examined using the chi-squared test and I2 statistics. This analysis uses the PRISMA statement as general guidance. 9 RCTs involving 3321 patients were included. The risk of PEP was lower in the nafamostat group than in the control group [4.4% vs. 8.3%, risk ratio (RR): 0.50, 95% confidence interval (CI): 0.36-0.68]. In subgroup analyses, the protective effects were evident in low-risk patients for PEP before ERCP (RR: 0.34, 95% CI: 0.21-0.55). The association between PEP and nafamostat was significant only in patients who developed mild PEP (RR: 0.49; 95% CI: 0.36-0.69). The benefits were independent of the dose. The prophylactic use of nafamostat resulted in a lower risk of PEP. The subgroup analyses suggested uncertain benefits for severe PEP or high-risk patients for PEP. This warrants further investigation through additional RCTs.

Drug repurposing for the treatment of COVID-19: Targeting nafamostat to the lungs by a liposomal delivery system

Despite tremendous global efforts since the beginning of the COVID-19 pandemic, still only a limited number of prophylactic and therapeutic options are available. Although vaccination is the most effective measure in preventing morbidity and mortality, there is a need for safe and effective post-infection treatment medication. In this study, we explored a pipeline of 21 potential candidates, examined in the Calu-3 cell line for their antiviral efficacy, for drug repurposing. Ralimetinib and nafamostat, clinically used drugs, have emerged as attractive candidates. Due to the inherent limitations of the selected drugs, we formulated targeted liposomes suitable for both systemic and intranasal administration. Non-targeted and targeted nafamostat liposomes (LipNaf) decorated with an Apolipoprotein B peptide (ApoB-P) as a specific lung-targeting ligand were successfully developed. The developed liposomal formulations of nafamostat were found to possess favorable physicochemical properties including nano size (119-147 nm), long-term stability of the normally rapidly degrading compound in aqueous solution, negligible leakage from the liposomes upon storage, and a neutral surface charge with low polydispersity index (PDI). Both nafamostat and ralimetinib liposomes showed good cellular uptake and lack of cytotoxicity, and non-targeted LipNaf demonstrated enhanced accumulation in the lungs following intranasal (IN) administration in non-infected mice. LipNaf retained its anti-SARS-CoV 2 activity in Calu 3 cells with only a modest decrease, exhibiting complete inhibition at concentrations >100 nM. IN, but not intraperitoneal (IP) treatment with targeted LipNaf resulted in a trend to reduced viral load in the lungs of K18-hACE2 mice compared to targeted empty Lip. Nevertheless, upon removal of outlier data, a statistically significant 1.9-fold reduction in viral load was achieved. This observation further highlights the importance of a targeted delivery into the respiratory tract. In summary, we were able to demonstrate a proof-of-concept of drug repurposing by liposomal formulations with anti-SARS-CoV-2 activity. The biodistribution and bioactivity studies with LipNaf suggest an IN or inhalation route of administration for optimal therapeutic efficacy.

Nafamostat mesilate for prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis: A systematic review and meta-analysis based on prospective, randomized, and controlled trials

OBJECTIVES

To evaluate the efficacy of nafamostat mesilate in the prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) by conduct a systematic review and meta-analysis.

METHOD

We retrieved for all randomized controlled trials (RCTs) about compare nafamostat mesilate with placebo in preventing PEP published before August 23, 2022, in 5 major electronic databases. The primary outcome was PEP rate, and the secondary outcome was post-ERCP hyperamylasemia (PEHA) rate. Subgroup analyses were performed to reveal the factors that may affect the preventive effect of nafamostat. Assessment of the quality of evidence was conducted based on Grading of Recommendations, Assessment, Development and Evaluations (GRADE) system.

RESULTS

According to the search strategy and criteria of inclusion and exclusion, 8 articles with a number of 3210 patients were included. The PEP incidence of the nafamostat group was inferior compared with the placebo group (4.6% vs 8.5%, RR = 0.50, 95% CI: 0.38-0.66). Subgroup analyses revealed that nafamostat had a preventive effect on patients with different risk stratification (High-risk: RR = 0.61, 95% CI: 0.43-0.86, Low-risk: RR = 0.28; 95% CI: 0.17-0.47). Different doses (20 mg: RR = 0.50, 95% CI: 0.36-0.69, 50 mg: RR = 0.45, 95% CI: 0.27-0.74) and duration (<12 hour: RR = 0.55, 95% CI: 0.37-0.81, ≥12 h: RR = 0.44, 95% CI: 0.29-0.66) of administration of nafamostat are adequate for the prevention of PEP, but postoperative administration may not help (preoperative: RR = 0.52, 95% CI: 0.39-0.69, postoperative: RR = 0.54, 95% CI: 0.23-1.23). Nafamostat may not efficacious in preventing severe PEP (Mild: RR = 0.49, 95% CI, 0.35-0.68, Moderate: RR = 0.47, 95% CI: 0.25-0.86, Severe: RR = 0.91, 95% CI, 0.25-3.29) or in low-quality studies (Low-quality: RR = 0.69, 95% CI: 0.13-3.60, High-quality: RR = 0.49, 95% CI: 0.37-0.65).

CONCLUSION

Preoperative use of nafamostat can effectively prevent PEP in patients with various risk stratification. Nafamostat can prevent mild and moderate PEP, but may not prevent severe PEP and PEHA. There should be more high-quality RCTs in future to strengthen the evidence of nafamostat in preventing PEP.

Incidence, severity, and mortality of post-ERCP pancreatitis: an updated systematic review and meta-analysis of 145 randomized controlled trials

BACKGROUND AND AIMS

The incidence, severity, and mortality of post-ERCP pancreatitis (PEP) largely remain unknown with changing trends in ERCP use, indication, and techniques. We sought to determine the incidence, severity, and mortality of PEP in consecutive and high-risk patients based on a systemic review and meta-analysis of patients in placebo and no-stent arms of randomized control trials (RCTs).

METHODS

The MEDLINE, Embase, and Cochrane databases were searched from the inception of each database to June 2022 to identify full-text RCTs evaluating PEP prophylaxes. The incidence, severity, and mortality of PEP from the placebo or no-stent arms of RCTs were recorded for consecutive and high-risk patients. A random-effects meta-analysis for a proportions model was used to calculate PEP incidence, severity, and mortality.

RESULTS

One hundred forty-five RCTs were found with 19,038 patients in the placebo or no-stent arms. The overall cumulative incidence of PEP was 10.2% (95% confidence interval [CI], 9.3-11.3), predominantly among the academic centers conducting such RCTs. The cumulative incidences of severe PEP and mortality were .5% (95% CI, .3-.7) and .2% (95% CI, .08-.3), respectively, across 91 RCTs with 14,441 patients. The cumulative incidences of PEP and severe PEP were 14.1% (95% CI, 11.5-17.2) and .8% (95% CI, .4-1.6), respectively, with a mortality rate of .2% (95% CI, 0-.3) across 35 RCTs with 3733 patients at high risk of PEP. The overall trend for the incidence of PEP among patients randomized to placebo or no-stent arms of RCTs has remained unchanged from 1977 to 2022 (P = .48).

CONCLUSIONS

The overall incidence of PEP is 10.2% but is 14.1% among high-risk patients based on this systematic review of placebo or no-stent arms of 145 RCTs; this rate has not changed between 1977 and 2022. Severe PEP and mortality from PEP are relatively uncommon.

Cryo-EM structures reveal the activation and substrate recognition mechanism of human enteropeptidase

Enteropeptidase (EP) initiates intestinal digestion by proteolytically processing trypsinogen, generating catalytically active trypsin. EP dysfunction causes a series of pancreatic diseases including acute necrotizing pancreatitis. However, the molecular mechanisms of EP activation and substrate recognition remain elusive, due to the lack of structural information on the EP heavy chain. Here, we report cryo-EM structures of human EP in inactive, active, and substrate-bound states at resolutions from 2.7 to 4.9 Å. The EP heavy chain was observed to clamp the light chain with CUB2 domain for substrate recognition. The EP light chain N-terminus induced a rearrangement of surface-loops from inactive to active conformations, resulting in activated EP. The heavy chain then served as a hinge for light-chain conformational changes to recruit and subsequently cleave substrate. Our study provides structural insights into rearrangements of EP surface-loops and heavy chain dynamics in the EP catalytic cycle, advancing our understanding of EP-associated pancreatitis.

The effect of nafamostat mesilate infusion after ERCP for post-ERCP pancreatitis

Background

Nafamostat mesilate decreases the incidence of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). However, no studies have administered nafamostat mesilate after ERCP. So we investigated if the infusion of nafamostat mesilate after ERCP can affect the post-ERCP pancreatitis (PEP) in high-risk patients.

Methods

In a tertiary hospital, 350 high-risk patients of PEP were reviewed retrospectively. Among them, 201 patients received nafamostat mesilate after ERCP. Patient-related and procedure-related risk factors for PEP were collected. We performed a propensity score matching to adjust for the significant different baseline characteristics. The incidence and severity of PEP were evaluated according to the infusion of nafamostat mesilate. The risk factors of PEP were also analyzed by multivariate logistic regression.

Results

The baseline characteristics were not different after the matching. The PEP rate (17.4% vs. 10.3%, P = 0.141) was insignificant. Among the PEP patients, mild PEP was significantly higher in the nafamostat mesilate group (85.7% vs. 45.5%, P = 0.021). Only one patient in the nafamostat mesilate group developed severe PEP. Although young age (odds ratio [OR] 3.60, 95% CI 1.09–11.85, P = 0.035) was a risk factor, nafamostat mesilate (odds ratio [OR] 0.30, 95% CI 0.09–0.98, P = 0.047) was a protective factor for moderate to severe PEP.

Conclusions

The administration of nafamostat mesilate after ERCP in high-risk patients was not effective in preventing PEP, but may attenuate the severity of PEP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02345-3.

Cooling the papilla with ice water in preventing post-ERCP pancreatitis (ice water challenge study)

BACKGROUND

The most common adverse event of endoscopic retrograde cholangiopancreatography (ERCP) is post-ERCP pancreatitis (PEP). The aim of this study was to investigate the efficacy of cooling the papilla with iced water to reduce PEP.

PATIENTS AND METHODS

Between December 2018 and July 2019, 100 consecutive patients with native papilla undergoing ERCP were prospectively enrolled in this study. In all patients, iced water was injected endoscopically toward the papilla via the working channel at the end of ERCP. The results were compared with 100 previous cases with native papilla that underwent ERCP under the same conditions without papilla cooling.

RESULTS

Although the difference was not significant, the incidence of PEP tended to be lower in the study group (4%) than in the control group (11%) (p = 0.060). In addition, the incidence of PEP was significantly reduced in patients who underwent biliary sphincterotomy (p = 0.033). All cases of PEP were mild.

CONCLUSIONS

Cooling the papilla with iced water injection, which is safe, easy, and cheap might reduce PEP.

Nafamostat Mesylate is Not Effective in Preventing Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis

BACKGROUND

Endoscopic retrograde cholangiopancreatography (ERCP) is associated with complications such as post-ERCP pancreatitis (PEP). Protease inhibitors, including nafamostat mesylate (NM), have been evaluated for prophylaxis against PEP.

AIM

We describe the first multicenter randomized controlled trial assessing the prophylactic efficacy of NM against PEP.

METHODS

In this multicenter prospective study, we aimed to enroll 800 patients aged ≥ 20 years with a planned ERCP between December 2012 and March 2019. The primary outcome was the incidence and severity of PEP in patients who did not receive NM (non-NM) versus those who did (NM; 20 mg). Secondary outcomes included the incidence of PEP by NM initiation (pre- and post-ERCP), risk factors for PEP, and NM-related adverse events.

RESULTS

Only 441 of the planned 800 patients were enrolled (non-NM: n = 149; NM: n = 292 [pre-ERCP NM: n = 144; post-ERCP NM: n = 148]). Patient characteristics were balanced at baseline with no significant differences between groups. PEP occurred in 40/441 (9%) patients (non-NM: n = 15 [10%]; NM: n = 25 [9%]), including 17 (12%) and eight (8%) in the pre-ERCP and post-ERCP NM groups, respectively. In the NM group, the incidence of PEP was lower in the low-risk group than in the high-risk group. Pancreatic injection and double-guidewire technique were independent risk factors for PEP. NM-related adverse events of hyperkalemia occurred in two (0.7%) patients.

CONCLUSIONS

We found no evidence for the prophylactic effect of NM against PEP, regardless of the timing of administration; however, further studies are needed.

Identification of impurities in nafamostat mesylate using HPLC-IT-TOF/MS: A series of double-charged ions

Nafamostat mesylate is a serine protease inhibitor used in the treatment of acute pancreatitis. The impurities in nafamostat mesylate, the active pharmaceutical ingredient (API), were profiled via high performance liquid chromatography tandem ion trap coupled with time-of-flight mass spectrometer (HPLC-IT-TOF/MS). The chromatography was performed on an ACE-3 C₁₈ column (200 mm × 4.6 mm, 3 μm) using methanol and 0.1% formic acid in purified water as mobile phase at a flow rate of 1.0 mL/min. The ions were detected by IT-TOF/MS with a full-scan mass analysis from m/z 100 to 800. In total, eleven impurities were detected in nafamostat mesylate API. The impurity profile was estimated based on the HPLC-IT-TOF/MS data, including accurate masses, MSⁿ fingerprints of fragmentation pathways and a series of double-charged ions. Finally, seven impurities were identified and reported for the first time. The results will provide technical support for the quality control and clinical safety of nafamostat mesylate.

Naproxen, isosorbide dinitrate and co-administration cannot prevent post-endoscopic retrograde cholangiopancreatography pancreatitis: Randomized controlled trial

Backgrounds/Aims

Acute pancreatitis is the most widespread complication of endoscopic retrograde cholangiopancreatography. Here, we investigated the efficacy of rectal suppository naproxen, sublingual isosorbide dinitrate and their co-administration in the prevention of post-ERCP pancreatitis.

Methods

This double-blind randomized clinical trial carried out from June 2015 to February 2016 at the Gastrointestinal and Liver Diseases Research Center in Rasht, Iran. A total of 585 patients were selected from candidates for diagnostic or therapeutic ERCP by using the simple sampling method. Patients divided into three groups. Group A received 500 mg naproxen, group B took 5 mg isosorbide dinitrate, and group C was co-administrated both agents before ERCP. The primary outcome measure was the development of pancreatitis onset of pain in the upper abdomen and increase of serum amylase activity more than 3 times over the upper normal limit (60-100 IU/L) within first the 24 h post-ERCP.

Results

Totally, 80 patients developed PEP included 29 (4.9%), 24 (4.1%), and 27 (4.6%) patients in groups A, B, and C, respectively (p=0.845). Longer ERCP time (p=0.041), using diazepam (p=0.033), a higher number of pancreatic ducts cannulation (p<0.001), pancreatic duct injection (p=0.013), and using pancreatic stent (p=0.004) were the predisposing factors for PEP.

Conclusions

Our findings indicated that prophylactic naproxen suppository or isosorbide dinitrate sublingually or co-administration had no significant difference in the prevention and severity of PEP, however, enhancing the endoscopist’s skills can be effective. Departments and educational hospitals should develop their assessment and quality assurance measures for the training of fellows’ not only technical training but also an understanding of the diagnostic and therapeutic roles of the procedure.

Post-endoscopic retrograde cholangiopancreatography pancreatitis: A systematic review for prevention and treatment

BACKGROUND

Post endoscopic retrograde cholangiopancreatography (ERCP) is comparatively complex application. Researchers has been investigated prevention of post-ERCP pancreatitis (PEP), since it has been considered to be the most common complication of ERCP. Although ERCP can lead various complications, it can also be avoided.

AIM

To study the published evidence and systematically review the literature on the prevention and treatment for PEP.

METHODS

A systematic literature review on the prevention of PEP was conducted using the electronic databases of ISI Web of Science, PubMed and Cochrane Library for relevant articles. The electronic search for the review was performed by using the search terms “Post endoscopic retrograde cholangiopancreatography pancreatitis” AND “prevention” through different criteria. The search was restricted to randomized controlled trials (RCTs) performed between January 2009 and February 2019. Duplicate studies were detected by using EndNote and deleted by the author. PRISMA checklist and flow diagram were adopted for evaluation and reporting. The reference lists of the selected papers were also scanned to find other relevant studies.

RESULTS

726 studies meeting the search criteria and 4 relevant articles found in the edited books about ERCP were identified. Duplicates and irrelevant studies were excluded by screening titles and abstracts and assessing full texts. 54 studies were evaluated for full text review. Prevention methods were categorized into three groups as (1) assessment of patient related factors; (2) pharmacoprevention; and (3) procedural techniques for prevention. Most of studies in the literature showed that young age, female gender, absence of chronic pancreatitis, suspected Sphincter of Oddi dysfunction, recurrent pancreatitis and history of previous PEP played a crucial role in posing high risks for PEP. 37 studies designed to assess the impact of 24 different pharmacologic agents to reduce the development of PEP delivered through various administration methods were reviewed. Nonsteroidal anti-inflammatory drugs are widely used to reduce risks for PEP. Rectal administration of indomethacin immediately prior to or after ERCP in all patients is recommended by European Society for Gastrointestinal Endoscopy guidelines to prevent the development of PEP. The majority of the studies reviewed revealed that rectally administered indomethacin had efficacy to prevent PEP. Results of the other studies on the other pharmacological interventions had both controversial and promising results. Thirteen studies conducted to evaluate the efficacy of 4 distinct procedural techniques to prevent the development of PEP were reviewed. Pancreatic Stent Placement has been frequently used in this sense and has potent and promising benefits in the prevention of PEP. Studies on the other procedural techniques have had inconsistent results.

CONCLUSION

Prevention of PEP involves multifactorial aspects, including assessment of patients with high risk factors for alternative therapeutic and diagnostic techniques, administration of pharmacological agents and procedural techniques with highly precise results in the literature.

Postendoscopic retrograde cholangiopancreatography pancreatitis

Endoscopic retrograde cholangiopancreatography (ERCP) has been a mainstay examination to clarify the biliary and pancreatic system. Not just diagnostic purpose, it could achieve therapeutic goal. Under the trend of more and more procedures about ERCP being interventional, the rate of adverse events after the procedure is increasing. Among them, post-ERCP pancreatitis (PEP) is the most common and sometimes tremendous complication. This mini-review will overview the PEP from definition, pathogenesis, and risk factors to prevention.

On the value of therapeutic interventions targeting the complement system in acute myocardial infarction

The complement system plays an important role in the inflammatory response subsequent to acute myocardial infarction (AMI). The aim of this study is to create a systematic overview of studies that have investigated therapeutic administration of complement inhibitors in both AMI animal models and human clinical trials. To enable extrapolation of observations from included animal studies toward post-AMI clinical trials, ex vivo studies on isolated hearts and proof-of-principle studies on inhibitor administration before experimental AMI induction were excluded. Positive therapeutic effects in AMI animal models have been described for cobra venom factor, soluble complement receptor 1, C1-esterase inhibitor (C1-inh), FUT-175, C1s-inhibitor, anti-C5, ADC-1004, clusterin, and glycosaminoglycans. Two types of complement inhibitors have been tested in clinical trials, being C1-inh and anti-C5. Pexelizumab (anti-C5) did not result in reproducible beneficial effects for AMI patients. Beneficial effects were reported in AMI patients for C1-inhibitor, albeit in small patient groups. In general, despite the absence of consistent positive effects in clinical trials thus far, the complement system remains a potentially interesting target for therapy in AMI patients. Based on the study designs of previous animal studies and clinical trials, we discuss several issues which require attention in the design of future studies: adjustment of clinical trial design to precise mechanism of action of administered inhibitor, optimizing the duration of therapy, and optimization of time point(s) on which therapeutic effects will be evaluated.

The "Scope" of Post-ERCP Pancreatitis

Pancreatitis is the most common adverse event of endoscopic retrograde cholangiopancreatography, with the potential for clinically significant morbidity and mortality. Several patient and procedural risk factors have been identified that increase the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). Considerable research efforts have identified several pharmacologic and procedural interventions that can drastically affect the incidence of PEP. This review article addresses the underlying mechanisms at play for the development of PEP, identifying patient and procedural risk factors and meaningful use of risk-stratification information, and details current interventions aimed at reducing the risk of this complication.

Endoscopic and pharmacological treatment for prophylaxis against postendoscopic retrograde cholangiopancreatography pancreatitis: a meta-analysis and systematic review

BACKGROUND AND AIM

Postendoscopic retrograde cholangiopancreatography (post-ERCP) pancreatitis (PEP) is the most common complication following ERCP. We carried out a systematic review and meta-analysis of the global literature on PEP prevention to provide clinical guidance and a framework for future research in this important field.

METHODS

PubMed, Embase, Science Citation Index, Ovid, and the Cochrane Controlled Trials Register were searched by two independent reviewers to identify full-length, prospective, randomized controlled trials (RCTs) published up until March 2016 investigating the use of pancreatic duct stents and pharmacological agents to prevent PEP.

RESULTS

Twelve RCTs comparing the risk of PEP after pancreatic duct stent placement (1369 patients) and 30 RCTs comparing pharmacological agents over placebo (10251 patients) fulfilled the inclusion criteria and were selected for final review and analysis. Meta-analysis showed that prophylactic pancreatic stents significantly decreased the odds of post-ERCP pancreatitis [odds ratio (OR), 0.28; 95% confidence interval (CI), 0.18-0.42]. Significant OR reduction of PEP was also observed in relation to rectal administration of diclofenac (OR, 0.24; 95% CI, 0.12-0.48) and rectal administration of indometacin (OR, 0.59; 95% CI, 0.44-0.79) compared with placebo. Subgroup analysis showed a significant reduction with bolus-administered somatostatin (OR, 0.23; 95% CI, 0.11-0.49). Subgroup analysis showed a significant reduction with bolus-administered somatostatin (OR, 0.23; 95% CI, 0.11-0.49).

CONCLUSION

Pancreatic stent placement, rectal diclofenac, and bolus administration of somatostatin appear to be most effective in preventing post-ERCP pancreatitis.

Update on innate immunity and perspectives on metabolite regulation in acute pancreatitis

PURPOSE OF REVIEW

Acute pancreatitis is a major cause of gastrointestinal morbidity for which specific therapy is greatly needed to prevent progression to and induce resolution of severe disease.

RECENT FINDINGS

Innate immune components and metabolite signaling are recently identified as strong determinants of disease severity and resolution in acute pancreatitis and this work will be discussed herein.

SUMMARY

Targeting innate immune cell populations and metabolite signaling pathways in acute pancreatitis may result in broader and ultimately more efficacious re-direction of the inflammatory programme toward disease resolution and improved clinical outcomes.

A Randomized Comparative Study of 24- and 6-Hour Infusion of Nafamostat Mesilate for the Prevention of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis: A Prospective Randomized Comparison Trial

OBJECTIVES

Although prolonged intravenous infusion (24 hours) of nafamostat mesilate is effective for the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis, it requires hospitalization and is expensive. The aim of this study was to compare the efficacy of 24- versus 6-hour intravenous infusion of 20 mg nafamostat mesilate for the prevention of post-ERCP pancreatitis (PEP).

METHODS

A total of 382 patients who underwent ERCP were randomly assigned into 2 groups: 24 hours or 6 hours. In both groups, nafamostat mesilate (20 mg) infusion was initiated up to an hour before ERCP and continued for either 24 or 6 hours.

RESULTS

The overall incidence of pancreatitis was 2.4% (9/371). The rates of PEP following 24- and 6-hour infusion were 2.8% (5/179) and 2.1% (4/192), respectively (P = 0.744). No significant difference was observed in the severity of pancreatitis between the groups. On multivariate analysis, increasing pancreatic duct cannulations (odds ratio, 1.685; 95% confidence interval, 1.036-2.741; P = 0.036) was identified as a statistically significant risk factor of PEP.

CONCLUSIONS

No difference was found in the incidence of PEP regardless of the duration of nafamostat mesilate infusion. Therefore, 6-hour infusion of 20 mg nafamostat mesilate may be useful for the prevention of PEP in an outpatient setting.

Evaluation of Pharmacologic Prevention of Pancreatitis After Endoscopic Retrograde Cholangiopancreatography: A Systematic Review

BACKGROUND & AIMS

There is controversy over the efficacy of pharmacologic agents for preventing pancreatitis after endoscopic retrograde cholangiopancreatography (PEP). We performed a systematic review of PEP pharmacoprevention to evaluate safety and efficacy.

METHODS

We performed a systematic search of the literature for randomized controlled trials (RCTs) and meta-analyses of PEP pharmacoprevention through February 2014. After identifying relevant studies, 2 reviewers each extracted information on study characteristics, clinical outcomes, and risk of bias. A research classification scale was developed to identify pharmacologic agents ready for clinical use, agents for which a confirmatory RCT should be considered a high priority, agents for which exploratory studies are still necessary, and agents for which additional research should be of low priority. Clinical and research recommendations for each agent were made by consensus after considering research classification results and other important factors such as magnitude of benefit, safety, availability, and cost.

RESULTS

After screening 851 citations and 263 potentially relevant articles, 2 reviewers identified 85 RCTs and 28 meta-analyses that were eligible. On the basis of these studies, rectal nonsteroidal anti-inflammatory drugs were found to be appropriate for clinical use, especially for high-risk cases. Sublingual nitroglycerin, bolus-administered somatostatin, and nafamostat were found to be promising agents for which confirmatory research is warranted. Additional research was found to be required to justify confirmatory RCTs for topical epinephrine, aggressive intravenous fluids, gabexate, ulinastatin, secretin, and antibiotics.

CONCLUSIONS

On the basis of a systematic review, NSAIDs are appropriate for use in prevention of PEP, especially for high-risk cases. Additional research is necessary to clarify the role of other pharmacologic agents. These findings could inform future research and guide clinical decision-making and policy.

Nafamostat mesilate for prevention of post-ERCP pancreatitis: a meta-analysis of prospective, randomized, controlled trials

OBJECTIVES

We aimed to evaluate the efficacy of nafamostat on the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).

METHODS

Medline, Embase, Cochrane Central Register of Controlled Trials, and Web of Science were searched until April 18, 2014.

RESULTS

Seven randomized controlled trials and 2956 patients met the search criteria. When compared with nonnafamostat, the incidence of PEP was reduced to 53% in the patients who received nafamostat (risk ratio [RR], 0.47; 95% confidence interval [CI], 0.34-0.63). Further analyses were conducted based on the different risk classifications (n = 641 in patients with high risks: RR, 0.54; 95% CI, 0.30-0.96 and n = 944 with low risks: RR, 0.31; 95% CI, 0.17-0.56), PEP severities (n = 1654: RR, 0.38; 95% CI, 0.25-0.59 for mild; RR, 0.37; 95% CI, 0.15-0.96 for moderate; RR, 0.92; 95% CI, 0.13-6.38 for severe), and nafamostat doses (n = 1902: RR, 0.42; 95% CI, 0.28-0.63 for 20 mg; n = 1150: RR, 0.40; 95% CI, 0.25-0.63 for 50 mg). However, there was no reduction of the incidence of post-ERCP hyperamylasemia (n = 1585; 95% CI, 0.68-1.45) or cannulation difficulty (n = 1585; 95% CI, 0.91-1.23).

CONCLUSIONS

Pooled analyses from current randomized controlled trials support the effectiveness of nafamostat for prophylaxis of PEP.

Randomized controlled trial for efficacy of nafamostat mesilate in preventing post-endoscopic retrograde cholangiopancreatography pancreatitis

OBJECTIVE

The objective of this study was to investigate whether prophylactic administration of nafamostat mesilate reduces the incidence of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP), its efficacy, and risk factors for PEP.

METHODS

Potential subjects comprised 876 patients who underwent ERCP between September 2008 and February 2011. Of these, 58 patients were excluded after meeting exclusion criteria, and 818 patients were randomized. Patients in the nafamostat mesilate group were administered 20 mg of nafamostat mesilate dissolved in 500 mL of 5% glucose solution, whereas the control group received 500 mL of 5% glucose solution alone, over 2 hours from the start of ERCP.

RESULTS

Post-ERCP pancreatitis occurred in 5.1% (41 patients) overall, with a significantly lower frequency in the nafamostat mesilate group (3.5%) than in the control group (6.7%; P = 0.0349). Analysis of the 322 patients who had undergone ERCP for the first time (n = 158 in the nafamostat mesilate group; n = 164 in the control group) found that PEP again significantly less frequently occurred in the nafamostat mesilate group (5.7%) than in the control group (13.4%; P = 0.0172).

CONCLUSIONS

Our randomized controlled study suggested that short-term administration of nafamostat mesilate 20 mg may reduce the incidence of PEP.

Incidence, severity, and mortality of post-ERCP pancreatitis: a systematic review by using randomized, controlled trials

BACKGROUND

Data regarding the incidence and severity of post-ERCP pancreatitis (PEP) are primarily from nonrandomized studies.

OBJECTIVE

To determine the incidence, severity, and mortality of PEP from a systematic review of the placebo or no-stent arms of randomized, controlled trials (RCTs).

DESIGN

MEDLINE, EMBASE, and Cochrane databases were searched to identify RCTs evaluating the efficacy of drugs and/or pancreatic stents to prevent PEP.

SETTING

Systematic review of patients enrolled in RCTs evaluating agents for PEP prophylaxis.

PATIENTS

Patients in the placebo or no-stent arms of the RCTs

INTERVENTION

ERCP.

MAIN OUTCOME MEASUREMENTS

Incidence, severity, and mortality of PEP.

RESULTS

There were 108 RCTs with 13,296 patients in the placebo or no-stent arms. Overall, the PEP incidence was 9.7% and the mortality rate was 0.7%. Severity of PEP was reported for 8857 patients: 5.7%, 2.6%, and 0.5% of cases were mild, moderate, and severe, respectively. The incidence of PEP in 2345 high-risk patients was 14.7% and the severity of PEP was mild, moderate, and severe in 8.6%, 3.9%, and 0.8%, respectively, with a 0.2% mortality rate. The incidence of PEP was 13% in North American RCTs compared with 8.4% in European and 9.9% in Asian RCTs. ERCPs conducted before and after 2000 had a PEP incidence of 7.7% and 10%, respectively.

LIMITATIONS

Difference in PEP risk among patients in the included RCTs.

CONCLUSION

The incidence of PEP and severe PEP is similar in high-risk patients and the overall cohort. Discrepancies in the incidence of PEP across geographic regions require further study.

Risk factors for post-ERCP pancreatitis: A systematic review and meta-analysis

BACKGROUND AND AIM

Pancreatitis is the most common and serious complication of diagnostic and therapeutic endoscopic retrograde cholangiopancreatography (ERCP). Prevention strategies targeting risk factors could be important to reduce the rate of post-ERCP pancreatitis. However, the risk factors for post-ERCP pancreatitis (PEP) are still debated. This systematic review and meta-analysis was performed to identify risk factors for PEP.

METHODS

Medline (PubMed and Ovid), Cochrane Central Register of Controlled trials & Database of Systematic Reviews, Embase, Scopus, ScienceDirect, Springer links and WEB OF SCIENCE were searched for published studies in all languages. Inclusion and exclusion criteria were defined a priori. Eighteen probable risk factors were evaluated, and outcomes were expressed in the case of dichotomous variables, as an odds ratio (OR) (with a 95% confidence interval, (CI)).

RESULTS

When patient-related risk factors were analyzed, the ORs for female gender was 1.46 (95%CI: 1.30-1.64); for previous pancreatitis 2.03 (95%CI: 1.31-3.14); for previous PEP was 2.90 (95%CI: 1.87-4.48); for Sphincter of Oddi dysfunction (SOD) was 2.04 (95%CI: 1.73-2.33) and for Intraductal papillary mucinous neoplasm (IPMN) was 3.01 (95%CI: 1.34-6.77). Four endoscopy-related factors were confirmed: the OR for difficult cannulation was 3.49 (95%CI: 1.364-8.925); for endoscopic sphincterotomy (EST) it was 1.39 (95%CI: 1.09-1.79); for precut sphincterotomy it was 2.25 (95%CI: 1.70_2.96); and for main pancreatic duct injection it was 1.58 (95%CI: 1.21-2.08).

CONCLUSIONS

Female gender, previous pancreatitis, previous PEP, SOD, IPMN, difficult cannulation, EST, precut sphincterotomy and main pancreatic duct injection are risk factors for post-ERCP pancreatitis.

Comparison between ulinastatin and nafamostat for prevention of post-endoscopic retrograde cholangiopancreatography complications: a prospective, randomized trial

OBJECTIVES

Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). The aim of this prospective trial was to compare the effect of ulinastatin and nafamostat on the prophylaxis of post-ERCP complications.

METHODS

A total of 159 patients who underwent ERCP were divided into ulinastatin (n = 53), nafamostat (n = 53) and control (n = 53) groups. Each patient received ulinastatin (150,000 units), nafamostat (20 mg), or placebo from 2-4 h before ERCP to 6-8 h after ERCP. The primary endpoint was the incidence of PEP, and the secondary endpoints were the incidence of post-ERCP hyperamylasemia, hyperlipasemia and abdominal pain.

RESULTS

The overall incidence of PEP was 6.3% (10/159) and no significant differences were observed between ulinastatin and nafamostat groups in terms of the incidences of PEP (1.9% and 3.8%, P = 0.560), hyperamylasemia, hyperlipasemia, and abdominal pain, although these were significantly lower than those of the control group (P < 0.001).

CONCLUSIONS

There was no significant difference for preventing PEP between ulinastatin and nafamostat and both drugs were efficacious for preventing post-ERCP complications.

How and when should NSAIDs be used for preventing post-ERCP pancreatitis? A systematic review and meta-analysis

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAIDs) have been shown to be efficacious to prevent pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). However, the target patients, the type of NSAID, the route of administration and the time of drug delivery remain unclear, as well as the potential efficacy in reducing the severity of pancreatitis, length of hospital stay and mortality. The objective of the study was to evaluate these questions by performing a systematic review and meta-analysis.

METHODS

Multiple searches were performed in the main databases. Randomized controlled trials (RCTs) comparing NSAIDs vs. placebo in the prevention of post-ERCP pancreatitis were included. Primary endpoint of the study was the efficacy for pancreatitis prevention. Sub-analyses were performed to determine the risk reduction in high and low risk patients, and to define optimal time, route of administration, and type of NSAID. Secondary endpoints were safety, moderate to severe pancreatitis prevention and reduction of hospital stay and mortality.

RESULTS

Nine RCTs enrolling 2133 patients were included. The risk of pancreatitis was lower in the NSAID group than in the placebo group (RR 0.51; 95%CI 0.39-0.66). The number needed to treat was 14. The risk of moderate to severe pancreatitis was also lower in the NSAID group. (RR 0.46; 95%CI 0.28-0.76). No adverse events related to NSAID use were reported. NSAIDs were effective in both high-risk and unselected patients (RR 0.53; 95%CI 0.30-0.93 and RR 0.57; 95%CI 0.37-0.88). In the subanalyses, only rectal administration of either indomethacin (RR 0.54; 95%CI 0.38-0.75) or diclofenac (RR 0.42; 95%CI 0.21-0.84) was shown to be effective. There were not enough data to perform a meta-analysis in hospital stay reduction. No deaths occurred.

CONCLUSION

A single rectal dose of indomethacin or diclofenac before or immediately after ERCP is safe and prevents procedure-related pancreatitis both in high risk and in unselected patients.

Pharmacologic prophylaxis of post-endoscopic retrograde cholangiopancreatography pancreatitis: protease inhibitors and NSAIDs in a meta-analysis

Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis is the most frequent complication of ERCP. Several meta-analyses have examined the effects of protease inhibitors (gabexate mesilate, ulinastatin, and nafamostat mesilate) and non-steroidal anti-inflammatory drugs (NSAIDs) on post-ERCP pancreatitis, but the results have been confusing. Since the previous meta-analysis, several new studies have been published on this topic. To provide an updated quantitative assessment of the effectiveness of protease inhibitors and NSAIDs in preventing post-ERCP pancreatitis, we conducted a meta-analysis of randomized trials for patients at risk of post-ERCP pancreatitis. Twenty-six articles were included in this meta-analysis. Nafamostat mesilate (summary RR = 0.41; 95 %CI 0.28-0.59; n = 4 studies) and NSAIDs (summary RR = 0.58; 95 %CI = 0.44-0.76; n = 7 studies) were associated with decreased risk of post-ERCP pancreatitis in the high-quality studies. However, gabexate mesilate (summary RR = 0.64; 95 %CI = 0.36-1.13; n = 6 studies) and ulinastatin (summary RR = 0.65; 95 %CI = 0.33-1.30; n = 2 studies) were not associated with decreased risk of post-ERCP pancreatitis in the high-quality studies. This is the first meta-analysis to compare the effects of three protease inhibitors. Solid evidence supports the use of nafamostat mesilate and NSAIDs for preventing post-ERCP pancreatitis.

Prophylactic pancreatic stent placement and post-ERCP pancreatitis: an updated meta-analysis

BACKGROUND AND AIM

Pancreatitis is one of the most frequent post-endoscopic retrograde cholangiopancreatography (ERCP) complications. Previous meta-analyses show that prophylactic pancreatic stent (PS) placement after ERCP is beneficial for the prevention of post-ERCP pancreatitis (PEP). However, the results of these meta-analyses are controversial due to the limited sample size of the eligible studies, in which six additional randomized controlled trials (RCTs) are not included. Our aim is, therefore, to update the current meta-analyses regarding PS placement for prevention of PEP.

METHODS

We conducted a meta-analysis to identify RCTs comparing PS placement and the subsequent incidence of PEP. The primary outcome was the incidence of PEP.

RESULTS

Fourteen studies were enrolled in this meta-analysis. Of the 1,541 patients, 760 patients received a PS and 781 patients were allocated to the control group. PS placement was associated with a statistically significant reduction of PEP [relative risk (RR) 0.39; 95 % confidence interval (CI) 0.29-0.53; P < 0.001]. Subgroup analysis stratified according to the severity of PEP showed that a PS was beneficial in patients with mild to moderate PEP (RR 0.45; 95 % CI 0.32-0.62; P < 0.001) and in patients with severe PEP (RR 0.26; 95 %CI 0.09-0.76; P = 0.01). In addition, subgroup analysis performed according to patient selection demonstrated that PS placement was effective for both high-risk and mixed case groups.

CONCLUSIONS

This meta-analysis showed that PS placement prevented PEP after ERCP as compared with no PS placement. We therefore recommend PS placement after ERCP for the prevention of PEP.

Results of the Tokyo trial of prevention of post-ERCP pancreatitis with risperidone-2: a multicenter, randomized, placebo-controlled, double-blind clinical trial

BACKGROUND

Our previous study suggested that a combination of ulinastatin and risperidone reduced post-ERCP pancreatitis (PEP) compared with ulinastatin alone.

OBJECTIVE

The aim of this study was to evaluate the efficacy of risperidone alone for prevention of PEP.

DESIGN

A multicenter, randomized, placebo-controlled, double-blind clinical trial.

SETTING

Two academic hospitals and 5 referral hospitals in Tokyo and Saitama, Japan.

PATIENTS

Patients undergoing therapeutic or interventional-diagnostic ERCP.

INTERVENTION

The patients were randomized to receive 2 mg of oral risperidone or oral placebo at 0.5 to 2 hours before ERCP.

MAIN OUTCOME MEASUREMENTS

The primary endpoint was the incidence of PEP. Secondary endpoints were the incidence of hyperenzymemia and enzyme levels (amylase, pancreatic amylase, lipase). Risk factors for PEP were evaluated.

RESULTS

We initially enrolled 500 patients in the study (250 in the risperidone group and 250 in the placebo group), but 17 (11 in the risperidone and 6 in the placebo group) were excluded after randomization. PEP developed in 24 patients (10.0%) in the risperidone group and 21 patients (8.6%) in the placebo group (P = .587). Serum amylase levels at 3 hours after ERCP were lower in the risperidone group (P = .007 in a single test of hypothesis, significance removed by Bonferroni correction for multiple testing). In multivariate analysis, a small papilla of Vater, total procedure time ≥40 minutes, and stenosis of the intrahepatic duct were significantly associated with PEP.

LIMITATIONS

Multiplicity of study centers and a relatively wide time range of drug administration time.

CONCLUSION

Risperidone did not show a benefit in prevention of PEP in this trial. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT000004592.).

Preventing pancreatitis after endoscopic retrograde cholangiopancreatography

Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis is a common and potentially devastating complication of ERCP. Advances in risk stratification, patient selection, procedure technique, and prophylactic interventions have substantially improved the endoscopists' ability to prevent this complication. This article presents the evidence-based approaches to preventing post-ERCP pancreatitis and suggests timely research questions in this important area.

Prospective, randomized, double-blind, placebo-controlled trial of ulinastatin for prevention of hyperenzymemia after double balloon endoscopy via the antegrade approach

BACKGROUND

Double balloon endoscopy (DBE) allows the entire small intestine to be viewed using a combination of antegrade and retrograde approaches. Acute pancreatitis is a serious complication of antegrade DBE with no effective prophylactic treatment currently available. Ulinastatin has been shown to be effective for the prevention of pancreatitis following endoscopic retrograde cholangiopancreatography. We therefore assessed the efficacy of ulinastatin for hyperenzymemia after antegrade DBE.

PATIENTS AND METHODS

Forty-four patients were enrolled in this prospective, randomized, double-blind, placebo-controlled trial. Patients in the ulinastatin group received 150 000 U ulinastatin by i.v. drip infusion for 2 h from the start of the procedure. Serum concentrations of pancreatic amylase and lipase were measured before and 3 and 18 h after antegrade DBE.

RESULTS

The study was terminated after interim analysis. Of the 44 patients, 23 were randomized to ulinastatin and 21 to placebo.The groups were similar with regard to sex ratio, age, type of endoscope, insertion time, total procedure time, number of endoscope pull-back procedures, and baseline pancreaticamylase and lipase concentrations. Post-DBE hyperenzymemia was observed in 35.0% and 47.8% of patients in the placebo and ulinastatin groups, respectively. The higher frequency of hyperenzymemia in the ulinastatin group was unexpected, but the difference was not statistically significant. One patient in the placebo group (5.0%) and none in the ulinastatin group experienced acute pancreatitis, but the difference was not statistically significant.

CONCLUSION

The results of this trial suggest that ulinastatin does not prevent hyperenzymemia following antegrade DBE.

Mast cells and vascular diseases

Mast cells are increasingly being recognized as effector cells in many cardiovascular conditions. Many mast-cell-derived products such as tryptase and chymase can, through their enzymic action, have detrimental effects on blood vessel structure while mast cell-derived mediators such as cytokines and chemokines can perpetuate vascular inflammation. Mice lacking mast cells have been developed and these are providing an insight into how mast cells are involved in cardiovascular diseases and, as knowledge increase, mast cells may become a viable therapeutic target to slow progression of cardiovascular disease.

Rethinking information delivery: using a natural language processing application for point-of-care data discovery

OBJECTIVE

This paper examines the use of Semantic MEDLINE, a natural language processing application enhanced with a statistical algorithm known as Combo, as a potential decision support tool for clinicians. Semantic MEDLINE summarizes text in PubMed citations, transforming it into compact declarations that are filtered according to a user's information need that can be displayed in a graphic interface. Integration of the Combo algorithm enables Semantic MEDLINE to deliver information salient to many diverse needs.

METHODS

The authors selected three disease topics and crafted PubMed search queries to retrieve citations addressing the prevention of these diseases. They then processed the citations with Semantic MEDLINE, with the Combo algorithm enhancement. To evaluate the results, they constructed a reference standard for each disease topic consisting of preventive interventions recommended by a commercial decision support tool.

RESULTS

Semantic MEDLINE with Combo produced an average recall of 79% in primary and secondary analyses, an average precision of 45%, and a final average F-score of 0.57.

CONCLUSION

This new approach to point-of-care information delivery holds promise as a decision support tool for clinicians. Health sciences libraries could implement such technologies to deliver tailored information to their users.

The use of gabexate mesylate and ulinastatin for the prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis

Background/Aims

Acute pancreatitis is a common complication of endoscopic retrograde cholangiopancreatography (ERCP). Only a few pharmacologic agents have been shown to have potential efficacy for the prophylactic treatment of post-ERCP pancreatitis (PEP). The aim of this study was to determine whether prophylactic gabexate and ulinastatin can decrease the incidence of PEP.

Methods

From January 2005 to April 2010, 1,679 patients undergoing ERCP treatment were consecutively enrolled in the study. After selective exclusion, a total of 1,480 patients were included in the analysis. The patients were separated into 3 groups according to the prophylactic administration of gabexate (593 patients), ulinastatin (229 patients), or saline solution (658 patients) and analyzed retrospectively. The primary outcome measurements were the incidence of pancreatitis and hyperamylasemia.

Results

PEP occurred in 21 of the 593 (3.5%) patients who received gabexate, 16 of the 229 (7.0%) patients who received ulinastatin, and 48 of the 658 (7.3%) patients who received a saline solution. The incidence of PEP was significantly different between the gabexate and ulinastatin or saline solution groups (p<0.05).

Conclusions

Gabexate prophylaxis is effective in preventing PEP. However, there is no difference in the beneficial effects of the prophylactic administration of ulinastatin and a saline solution.

Is high-dose nafamostat mesilate effective for the prevention of post-ERCP pancreatitis, especially in high-risk patients?

OBJECTIVE

Infusion of the protease inhibitor nafamostat mesilate (20 mg) effectively prevents post-ERCP pancreatitis, but only in low-risk groups. This study was performed to evaluate the use of high-dose nafamostat mesilate (50 mg) for prevention of post-ERCP pancreatitis (PEP), especially in high-risk groups.

METHODS

A total of 608 patients who underwent ERCP were included; 13 patients were excluded. Patients were divided into 3 groups: controls (group A), infusion with 20 mg of nafamostat mesilate (group B), or infusion with 50 mg of nafamostat mesilate (group C). The incidence of PEP was analyzed.

RESULTS

The overall incidence of acute pancreatitis was 7.4% (44/595). There was a significant difference in the incidence of PEP with or without nafamostat mesilate (13.0% vs 4.0% and 5.1%, respectively; P < 0.0001). Subgroup analysis showed that in low-risk patients, the rate of PEP was significantly different with nafamostat (11.9% vs 2.7% and 4.0%, respectively; P = 0.007). In high-risk patients, the rate of PEP was not significantly different among treatment groups (14.6% vs 5.9% vs 6.9%, respectively; P = 0.108).

CONCLUSIONS

Nafamostat mesilate prophylaxis (20 or 50 mg) is effective in preventing post-ERCP pancreatitis. However, the preventive effect of high-dose nafamostat mesilate (50 mg) is not significant in high-risk patients.

Use of udenafil is not associated with a reduction in post-ERCP pancreatitis: results of a randomized, placebo-controlled, multicenter trial

BACKGROUND

Udenafil, a phosphodiesterase-5 inhibitor, may decrease sphincter of Oddi tone and allow efficient cannulation.

OBJECTIVE

To determine whether prophylactic udenafil reduces the rates of occurrence of post-ERCP pancreatitis.

DESIGN

Prospective, randomized, double-blind, placebo-controlled, multicenter study.

SETTING

Three academic medical centers.

PATIENTS

From November 2008 to November 2010, a total of 278 patients who underwent ERCP were analyzed.

INTERVENTION

ERCP.

MAIN OUTCOME MEASUREMENT

Rate of post-ERCP pancreatitis.

RESULTS

Demographic features, indications for ERCP, and therapeutic procedures were similar in each group. The overall rate of pancreatitis was 7.9% (22/278). There was no significant difference in the rate (8.0% [11/137] vs 7.8% [11/141], P = .944) and severity of post-ERCP pancreatitis between the udenafil and placebo groups. Severe pancreatitis developed in 1 patient in the placebo group. On both univariate and multivariate analyses, age 40 years or younger, suspected sphincter of Oddi dysfunction, complete pancreatic duct opacification, and failed cannulation were associated with post-ERCP pancreatitis. Only mild udenafil-related complications occurred, including flushing (n = 3) and headache (n = 3).

LIMITATIONS

Unselected patient group, overestimation of the rate of pancreatitis in the placebo group.

CONCLUSION

Udenafil was not effective for prevention of post-ERCP pancreatitis in this study. (

CLINICAL TRIAL REGISTRATION NUMBER

KCT0000021.).

Prevention of Post-ERCP Pancreatitis

Pancreatitis is the most common complication of ERCP. It can be associated with substantial morbidity. Hence, the minimization of both the incidence and severity of post-ERCP pancreatitis is paramount. Considerable efforts have been made to identify factors that may be associated with an increased risk of this complication. In addition, both procedure- and pharmacological-related interventions have been proposed that may prevent this complication. This paper outlines these interventions and presents the evidence to support their use in the prevention of post-ERCP pancreatitis.

Protease inhibitors for preventing complications associated with ERCP: an updated meta-analysis

BACKGROUND AND OBJECTIVES

The prophylactic use of protease inhibitors in patients undergoing ERCP is still controversial. Our purpose was to evaluate the efficacy of protease inhibitors in preventing ERCP-associated complications.

DESIGN AND SETTING

Meta-analysis; randomized trials that evaluated the efficacy of protease inhibitors were identified.

PATIENTS

A total of 4966 patients were evaluated.

MAIN OUTCOME MEASUREMENTS

ERCP-associated pancreatitis, hyperamylasemia, abdominal pain, and death.

RESULTS

Eighteen studies (19 cohorts) met the inclusion criteria. Overall results for protease inhibitors showed a significant but small risk reduction in ERCP-associated pancreatitis (pooled risk difference [RD]: -0.029; 95% CI, -0.051 to -0.008 and the number needed to treat, 34.5; 95% CI, 19.6-125). Subgroup analysis in 8 high-quality studies showed a borderline significant efficacy (pooled RD, -0.027; 95% CI, -0.051 to -0.004). Subgroup analysis in 8 gabexate studies did not show significant efficacy (pooled RD, -0.030; 95% CI, -0.062 to 0.003). Subgroup analysis in 5 ulinastatin studies was significant (pooled RD, -0.035; 95% CI, -0.063 to -0.006). Two high-quality studies on ulinastatin yielded nonsignificant results. Analyses for the other outcomes were all nonsignificant. Sensitivity analysis showed that the effect size and level of statistical significance were decreased with increasing study quality.

CONCLUSIONS

At present, there is no solid evidence to support the use of protease inhibitors to prevent ERCP-associated complications. Although overall and ulinastatin subgroup analyses showed a small risk reduction for pancreatitis, it seems very possible that low-quality primary studies produced a veneer of efficacy.

Nafamostat mesilate for prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis: a prospective, randomized, double-blind, controlled trial

OBJECTIVES

Pancreatitis is the most common major complication of endoscopic retrograde cholangiopancreatography (ERCP). Efforts have been made to identify pharmacologic agents capable of reducing its incidence and severity. The aim of this trial was to determine whether prophylactic nafamostat mesilate, a synthetic protease inhibitor, would reduce the frequency and severity of post-ERCP pancreatitis.

METHODS

A total of 286 patients were randomized to receive either intravenous nafamostat mesilate or placebo 60 minutes before ERCP and for 6 hours after ERCP. A database was prospectively collected by a defined protocol. Standardized criteria were used to diagnose and grade the severity of pancreatitis.

RESULTS

The groups were similar with regard to patient demographics and to patient and procedure risk factors for pancreatitis. The overall incidence of pancreatitis was 5.9%. It occurred in 4 (2.8%) of 143 patients in the nafamostat group and in 13 (9.1%) of 143 patients in the control group (P = 0.03). Pancreatitis was graded mild in 2.1% and moderate in 0.7% of the nafamostat group and mild in 7.0% and moderate in 2.1% of the control group. There was no significant difference between the groups in the severity of pancreatitis.

CONCLUSIONS

Prophylactic intravenous nafamostat mesilate reduces the frequency of post-ERCP pancreatitis.

Endoscopy: a guide for the registered nurse

As an invasive procedure, endoscopic studies require patient care and considerations that are very similar to minor surgical procedures. There are some general guidelines that are applicable to all endoscopic procedures, and there are special considerations that are dictated by the specific endoscopic procedure. It is important for the critical care nurse to understand the procedures because the differences and similarities of each procedure guide nursing actions to effect the best patient outcomes.

Endoscopic retrograde cholangiopancreatography associated pancreatitis: A 15-year review

The aim of this article is to review the literature regarding post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis. We searched for and evaluated all articles describing the diagnosis, epidemiology, pathophysiology, morbidity, mortality and prevention of post-ERCP pancreatitis (PEP) in adult patients using the PubMed database. Search terms included endoscopic retrograde cholangiopancreatography, pancreatitis, ampulla of vater, endoscopic sphincterotomy, balloon dilatation, cholangiography, adverse events, standards and utilization. We limited our review of articles to those published between January 1, 1994 and August 15, 2009 regarding human adults and written in the English language. Publications from the reference sections were reviewed and included if they were salient and fell into the time period of interest. Between the dates queried, seventeen large (> 500 patients) prospective and four large retrospective trials were conducted. PEP occurred in 1%-15% in the prospective trials and in 1%-4% in the retrospective trials. PEP was also reduced with pancreatic duct stent placement and outcomes were improved with endoscopic sphincterotomy compared to balloon sphincter dilation in the setting of choledocholithiasis. Approximately 34 pharmacologic agents have been evaluated for the prevention of PEP over the last fifteen years in 63 trials. Although 22 of 63 trials published during our period of review suggested a reduction in PEP, no pharmacologic therapy has been widely accepted in clinical use in decreasing the development of PEP. In conclusion, PEP is a well-recognized complication of ERCP. Medical treatment for prevention has been disappointing. Proper patient selection and pancreatic duct stenting have been shown to reduce the complication rate in randomized clinical trials.

NSAIDs and Acute Pancreatitis: A Systematic Review

The resulting pain is the main symptom of acute pancreatitis and it should be alleviated as soon as possible. NSAIDs are the first line therapy for pain and they are generally administered to acute pancreatitis patients upon admission to the hospital. In addition, these drugs have also been used to prevent post-endoscopic cholangiopancreatography (ERCP) acute pancreatitis. On the other hand, there are several reports indicating that NSAIDs may be the actual cause of acute pancreatitis. We carried out a literature search on PubMed/MEDLINE; all full text papers published in from January 1966 to November 2009 on the use of NSAIDs in acute pancreatitis were collected; the literature search was also supplemented by a review of the bibliographies of the papers evaluated. Thus, in this article, we will systematically review the current literature in order to better illustrate the role of NSAIDs in acute pancreatitis, in particular: i) NSAIDs as a cause of acute pancreatitis; ii) their use to prevent post-retrograde ERCP pancreatitis and iii) their efficacy for pain relief in the acute illness of the pancreas.