Sphincterotomy for biliary sphincter of Oddi disorder and idiopathic acute recurrent pancreatitis: the RESPOnD longitudinal cohort.

OBJECTIVE: Sphincter of Oddi disorders (SOD) are contentious conditions in patients whose abdominal pain, idiopathic acute pancreatitis (iAP) might arise from pressurisation at the sphincter of Oddi. The present study aimed to measure the benefit of sphincterotomy for suspected SOD. DESIGN: Prospective cohort conducted at 14 US centres with 12 months follow-up. Patients undergoing first-time endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy for suspected SOD were eligible: pancreatobiliary-type pain with or without iAP. The primary outcome was defined as the composite of improvement by Patient Global Impression of Change (PGIC), no new or increased opioids and no repeat intervention. Missing data were addressed by hierarchal, multiple imputation scheme. RESULTS: Of 316 screened, 213 were enrolled with 190 (89.2%) of these having a dilated bile duct, abnormal labs, iAP or some combination. By imputation, an average of 122/213 (57.4% (95% CI 50.4% to 64.4%)) improved; response rate was similar for those with complete follow-up (99/161, 61.5% (54.0% to 69.0%)); of these, 118 (73.3%) improved by PGIC alone. Duct size, elevated labs and patient characteristics were not associated with response. AP occurred in 37/213 (17.4%) at a median of 6 months post ERCP and was more likely in those with a history of AP (30.9% vs 2.9%, p<0.0001). CONCLUSION: Nearly 60% of patients undergoing ERCP for suspected SOD improve, although the contribution of a placebo response is unknown. Contrary to prevailing belief, duct size and labs are poor response predictors. AP recurrence was common and like observations from prior non-intervention cohorts, suggesting no benefit of sphincterotomy in mitigating future AP episodes.

Rise in First-Time ERCP for Benign Indications >1 Year After Cholecystectomy Is Associated With Worse Outcomes.

BACKGROUND & AIMS: Greater availability of less invasive biliary imaging to rule out choledocholithiasis should reduce the need for diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in patients who have a remote history of cholecystectomy. The primary aims were to determine the incidence, characteristics, and outcomes of individuals who undergo first-time ERCP >1 year after cholecystectomy (late-ERCP). METHODS: Data from a commercial insurance claim database (Optum Clinformatics) identified 583,712 adults who underwent cholecystectomy, 4274 of whom underwent late-ERCP, defined as first-time ERCP for nonmalignant indications >1 year after cholecystectomy. Outcomes were exposure and temporal trends in late-ERCP, biliary imaging utilization, and post-ERCP outcomes. Multivariable logistic regression was used to examine patient characteristics associated with undergoing late-ERCP. RESULTS: Despite a temporal increase in the use of noninvasive biliary imaging (35.9% in 2004 to 65.6% in 2021; P < .001), the rate of late-ERCP increased 8-fold (0.5-4.2/1000 person-years from 2005 to 2021; P < .001). Although only 44% of patients who underwent late-ERCP had gallstone removal, there were high rates of post-ERCP pancreatitis (7.1%), hospitalization (13.1%), and new chronic opioid use (9.7%). Factors associated with late-ERCP included concomitant disorder of gut-brain interaction (odds ratio [OR], 6.48; 95% confidence interval [CI], 5.88-6.91) and metabolic dysfunction steatotic liver disease (OR, 3.27; 95% CI, 2.79-3.55) along with use of anxiolytic (OR, 3.45; 95% CI, 3.19-3.58), antispasmodic (OR, 1.60; 95% CI, 1.53-1.72), and chronic opioids (OR, 6.24; 95% CI, 5.79-6.52). CONCLUSIONS: The rate of late-ERCP postcholecystectomy is increasing significantly, particularly in patients with comorbidities associated with disorder of gut-brain interaction and mimickers of choledocholithiasis. Late-ERCPs are associated with disproportionately higher rates of adverse events, including initiation of chronic opioid use.

Impact of repeated micro and macro blood sampling on clinical chemistry and haematology in rats for toxicokinetic studies.

Non-clinical rodent safety studies are essential in the development of new medicines to assess for potential adverse effects. Typically, toxicokinetic samples are collected from a satellite group. AstraZeneca implemented repeated microsampling of main study animals as standard in the one-month small molecule regulatory toxicology studies. A retrospective analysis of the clinical chemistry and haematology data collected in 52 independent studies from the adult rat controls explored the impact of micro and macro sampling of main study animals. For the majority of variables, the blood sampling technique had no significant impact on the mean or range. For microsampling, a few variables had statistically significant effects on the mean signal but these were considered to have limited biological relevance and would therefore not introduce a meaningful bias to any toxicological evaluation. The macrosampling had the expected effects on the red cell parameters of haemoglobin, haematocrit and red blood count due to the larger blood volume draw. In contrast, microsampling showed no such changes. In conclusion, this large-scale retrospective analysis supports the use of microsampling, for toxicokinetics, of main study animals and enables us to conduct rodent toxicology studies without satellite animals and further reduce the number of animals used in toxicological assessments.

Characteristics of Patients Undergoing Endoscopic Retrograde Cholangiopancreatography for Sphincter of Oddi Disorders.

The concept that sphincter of Oddi dysfunction (SOD) can cause attacks of biliary-type pain in postcholecystectomy patients and those with unexplained recurrent acute pancreatitis, and that endoscopic sphincterotomy can ameliorate symptoms, remains unproven. The Evaluating Predictors and Interventions in Sphincter of Oddi Dysfunction (EPISOD) study of patients without objective evidence for biliary obstruction showed no difference in outcomes between those who underwent sphincterotomy or sham treatment.1 To date, there have been no studies examining the characteristics of patients who still are being offered endoscopic retrograde cholangiopancreatography (ERCP) for SOD since the EPISOD publication, although the absolute number appears to have declined.2.

Comparison of Urologist- vs Gastroenterologist-Directed Extracorporeal Shock Wave Lithotripsy for Pancreaticolithiasis.

BACKGROUND & AIMS: Extracorporeal shock wave lithotripsy (ESWL) for pancreaticolithiasis is most commonly performed by urologists. We investigated the effects of transitioning from urologist- to gastroenterologist-directed ESWL on case complexity, process measures, and duct clearance. METHODS: We performed a retrospective study of patients who underwent ESWL for pancreaticolithiasis from 2014 through 2019 at a single center. We collected demographic, clinical, radiographic, and procedural data in duplicate and compared case complexity and process measures between the periods the procedure was performed by urologists (January 2014 through February 2017; 18 patients, 0.47 patients/month) vs gastroenterologists (March 2017 through December 2019; 61 patients; 1.79 patients/month). We also compared data on pancreatic duct stone characteristics and technical success (duct clearance, determined by imaging analysis). RESULTS: There were no differences in patient demographics, comorbidities, pancreatic stone morphology, or time from referral to ESWL during the period the procedure was performed by urologists vs gastroenterologists. Patients received a higher mean number of ESWL shocks per session during the gastroenterology period (4341) than during the urology period (3117) (P < .001). A higher proportion of patients underwent same-session endoscopic retrograde cholangiopancreatography during the gastroenterology time period (66%) than the urology time period (6%) (P < .001). A higher proportion of patients had partial or complete duct clearance during the gastroenterology period (71%) than during the urology period (44%) (P = .04). During the urology period, a higher proportion of patients were hospitalized following ESWL, although there was no difference in captured adverse events between the periods. CONCLUSIONS: Transition from urologist- to gastroenterologist-directed ESWL did not affect case complexity or wait times for ESWL. However, the transition did result in increased procedure volume, more shocks per ESWL session, and improved duct clearance.

Development and initial validation of an instrument for video-based assessment of technical skill in ERCP.

BACKGROUND AND AIMS: The accurate measurement of technical skill in ERCP is essential for endoscopic training, quality assurance, and coaching of this procedure. Hypothesizing that technical skill can be measured by analysis of ERCP videos, we aimed to develop and validate a video-based ERCP skill assessment tool. METHODS: Based on review of procedural videos, the task of ERCP was deconstructed into its basic components by an expert panel that developed an initial version of the Bethesda ERCP Skill Assessment Tool (BESAT). Subsequently, 2 modified Delphi panels and 3 validation exercises were conducted with the goal of iteratively refining the tool. Fully crossed generalizability studies investigated the contributions of assessors, ERCP performance, and technical elements to reliability. RESULTS: Twenty-nine technical elements were initially generated from task deconstruction. Ultimately, after iterative refinement, the tool comprised 6 technical elements and 11 subelements. The developmental process achieved consistent improvements in the performance characteristics of the tool with every iteration. For the most recent version of the tool, BESAT-v4, the generalizability coefficient (a reliability index) was .67. Most variance in BESAT scores (43.55%) was attributed to differences in endoscopists' skill, indicating that the tool can reliably differentiate between endoscopists based on video analysis. CONCLUSIONS: Video-based assessment of ERCP skill appears to be feasible with a novel instrument that demonstrates favorable validity evidence. Future steps include determining whether the tool can discriminate between endoscopists of varying experience levels and predict important outcomes in clinical practice.

Ecological mechanisms explaining interactions within plant-hummingbird networks: morphological matching increases towards lower latitudes.

Interactions between species are influenced by different ecological mechanisms, such as morphological matching, phenological overlap and species abundances. How these mechanisms explain interaction frequencies across environmental gradients remains poorly understood. Consequently, we also know little about the mechanisms that drive the geographical patterns in network structure, such as complementary specialization and modularity. Here, we use data on morphologies, phenologies and abundances to explain interaction frequencies between hummingbirds and plants at a large geographical scale. For 24 quantitative networks sampled throughout the Americas, we found that the tendency of species to interact with morphologically matching partners contributed to specialized and modular network structures. Morphological matching best explained interaction frequencies in networks found closer to the equator and in areas with low-temperature seasonality. When comparing the three ecological mechanisms within networks, we found that both morphological matching and phenological overlap generally outperformed abundances in the explanation of interaction frequencies. Together, these findings provide insights into the ecological mechanisms that underlie geographical patterns in resource specialization. Notably, our results highlight morphological constraints on interactions as a potential explanation for increasing resource specialization towards lower latitudes.

The EPISOD study: long-term outcomes.

BACKGROUND AND AIMS: The EPISOD (Evaluating Predictors and Interventions in Sphincter of Oddi Dysfunction) study randomized patients with post-cholecystectomy pain, and little or no objective evidence for biliary obstruction, to sphincterotomy or sham intervention. Results at 1 year showed no benefit for the active treatment. We now report the outcomes at up to 5 years. METHODS: One hundred three patients completing 1 year, and still blinded to treatment allocation, were enrolled and followed by phone every 6 months for a median of 58 months (range, 17-71 months). Their success was assessed at the final visit by 2 criteria: (1) a low pain score (Recurrent Abdominal Pain and Disability instrument [RAPID] <6) and (2) much or very much improved on the Patients' Global Impression of Change (PGIC) questionnaire (both with no repeat intervention and not taking narcotics). RESULTS: By the RAPID criteria, success rates for the patients in the sphincterotomy and sham arms were similar: 26/65 (40%) versus 16/38 (42%), respectively. However, by the PGIC criteria, actively treated patients fared worse: 16/43 (37%) versus 16/22 (73%). A total of 75 patients underwent active treatment during the entire study. Their success rate by the RAPID criteria was 31 (41%) compared with 16 (62%) who had no active treatment at any time. CONCLUSIONS: These data confirm our initial report that endoscopic sphincterotomy is no better than sham intervention in these patients (and, by some criteria, worse), and that ERCP can no longer be recommended. The patients have genuine and often severe symptoms, and further research is needed to establish effective management. (Clinical trial registration number: 00688662 05/3/2008.).

Trends in the timing of inpatient ERCP relative to cholecystectomy: a nationwide database studied longitudinally.

BACKGROUND AND AIMS: ERCP has largely replaced common bile duct exploration for therapy of common bile duct pathology, yet its use as a purely diagnostic test has declined. Among inpatients, we hypothesized that timing between ERCP and cholecystectomy (CCY) has changed. The objectives were to measure temporal trends in the timing between inpatient ERCP and CCY and to examine factors associated with delays. METHODS: We used the National Inpatient Sample between 1998 and 2013 to classify admissions for gallstone-related diagnoses undergoing inpatient CCY and ERCP by timing relative to CCY: within (±) 1 day, ≥2 days before, and ≥2 days after. Logistic regression and Poisson regression were used to determine pattern utilization and association of ERCP timing on hospital length of stay. RESULTS: Between 1998 and 2013, the proportion of admissions for CCY associated with same-stay ERCP increased (14.5% in 1998 to 17.3% in 2013, P < .001), and approximately two-thirds of ERCPs were performed within 1 day of CCY. After adjusting for covariates, the mean adjusted length of stay remained significantly shorter for patients who underwent CCY within 1 day of ERCP (5.13 vs 7.48 days for ERCP ≥2 days before and vs 7.41 days for ERCP ≥2 days after, P < .001). CONCLUSIONS: Use of inpatient ERCP in conjunction with CCY has increased minimally between 1998 and 2013, whereas length of stay has decreased. ERCPs performed within 1 day of CCY were associated with shorter hospital length of stay, suggesting delays between inpatient procedures should be minimized unless medical comorbidities preclude it.

How much pain relief do patients expect after cholecystectomy?

BACKGROUND: Cholecystectomy is a common operation, increasingly performed, in the USA, for "functional gall bladder disorder" (FGBD). Outcomes of these surgeries are uncertain. In planning a study of FGBD, we needed to define the best outcome measures. METHODS: We sought the opinions of patients (52 with FGBD and 100 with stones for comparison) coming to cholecystectomy. They were asked to respond in four ways about the minimum benefit they would count as "success." RESULTS: We found that most patients do not expect cholecystectomy to relieve their pain-related disability completely, regardless of the presence or absence of stones. CONCLUSIONS: Future studies of the success of surgery should use patient-centered outcome assessments, such as PGIC (patient's global impression of change), in addition to objective measures of the impact of treatment on key symptoms, such as pain.

A survey of credentialing for ERCP in the United States.

BACKGROUND AND AIMS: There are limited data measuring the variability in standards used by hospitals for credentialing physicians to ERCP in the United States. METHODS: We performed an electronic survey of U.S. gastroenterologists. RESULTS: Among 1126 respondents, 21% reported that their hospitals had no written guidelines for initial credentialing, and 59% reported that their hospitals had no written guidelines for repeat credentialing. Among those with guidelines, less than half had any of the criteria recommended by the American Society for Gastrointestinal Endoscopy. CONCLUSIONS: There is an urgent need to improve the credentialing process to enhance practice and to protect patients. An easy-to-use national system for recording and reporting ERCP quality data, like that of the GI Quality Improvement Consortium, is needed.

High proportion of smaller ranged hummingbird species coincides with ecological specialization across the Americas.

Ecological communities that experience stable climate conditions have been speculated to preserve more specialized interspecific associations and have higher proportions of smaller ranged species (SRS). Thus, areas with disproportionally large numbers of SRS are expected to coincide geographically with a high degree of community-level ecological specialization, but this suggestion remains poorly supported with empirical evidence. Here, we analysed data for hummingbird resource specialization, range size, contemporary climate, and Late Quaternary climate stability for 46 hummingbird-plant mutualistic networks distributed across the Americas, representing 130 hummingbird species (ca 40% of all hummingbird species). We demonstrate a positive relationship between the proportion of SRS of hummingbirds and community-level specialization, i.e. the division of the floral niche among coexisting hummingbird species. This relationship remained strong even when accounting for climate, furthermore, the effect of SRS on specialization was far stronger than the effect of specialization on SRS, suggesting that climate largely influences specialization through species' range-size dynamics. Irrespective of the exact mechanism involved, our results indicate that communities consisting of higher proportions of SRS may be vulnerable to disturbance not only because of their small geographical ranges, but also because of their high degree of specialization.

An assessment of existing risk stratification guidelines for the evaluation of patients with suspected choledocholithiasis.

BACKGROUND: Prior studies have demonstrated that existing risk stratification guidelines for the evaluation of suspected choledocholithiasis lack accuracy, leading to the overutilization of endoscopic retrograde cholangiopancreatography (ERCP). The aim of our study was to evaluate the performance characteristics of published guidelines in predicting choledocholithiasis and to determine the impact of laboratory trends on diagnostic accuracy. METHODS: We identified patients with suspected choledocholithiasis hospitalized over a 5-year period (2009-2014) at a tertiary care academic medical center. Among eligible patients, we assessed the performance characteristics of the American Society for Gastrointestinal Endoscopy (ASGE) guidelines predicting the presence of choledocholithiasis, confirmed by endoscopic ultrasound, magnetic resonance cholangiography, ERCP, or intra-operative cholangiography. We also evaluated whether a second set of liver function tests improved the accuracy of the guidelines. RESULTS: On presentation, 71 of the 173 eligible patients (41.4 %) met ASGE high-probability criteria for choledocholithiasis. Of these, only 39 (54.9 %) were found to have a choledocholithiasis on confirmatory testing. Conversely, of the 102 patients (58.6 %) who were classified as low or intermediate probability, 32 (31.4 %) had choledocholithiasis. Overall, the accuracy of the guidelines was 63 % (sensitivity 54.9 %; specificity 68.6 %). Incorporating a second set of laboratory tests did not improve accuracy (62.7 %), and a significant decline in liver function tests did not reliably predict spontaneous stone passage. CONCLUSIONS: Existing guidelines performed suboptimally for predicting choledocholithiasis in our patient population, similar to other validation studies. These findings further underscore the importance of developing alternate risk stratification tools for choledocholithiasis, aiming to minimize unnecessary diagnostic ERCP.

Duloxetine for the Treatment of Patients with Suspected Sphincter of Oddi Dysfunction: A Pilot Study.

OBJECTIVE: To examine the tolerability and efficacy of duloxetine in patients with suspected sphincter of Oddi dysfunction (SOD). METHODS: An open-label, single-center, 12-week trial of duloxetine 60 mg once daily was conducted in 20 patients with suspected SOD. All patients were evaluated by expert pancreato-biliary specialists. The primary outcome measure was a Patient Global Impression of Change (PGIC) scale. Secondary measures included the pain burden, assessed by the Recurrent Abdominal Pain Intensity and Disability scale, the Short-Form Health Survey, and the Hospital Anxiety and Depression Scale. A positive clinical response was defined as a PGIC score of much or very much improved at 3 months and was estimated using a two-sided 90 % confidence interval. The primary outcome was analyzed using a one-sample binomial test at a significance level of 0.10. RESULTS: Of the 20 screened patients, 18 were enrolled; 14 completed at least one post-baseline evaluation; and 10 patients completed the third month endpoint visit. Patients missing the third month visit were considered non-responders for the primary outcome. Response rates were 90 % for study completers (n = 10; 90 % CI 74-100; p = 0.02) and 64 % for patients who completed at least one post-baseline evaluation (n = 14; 90 % CI 43-85; p = 0.42). Seven patients did not complete the study due to adverse events (mostly fatigue and nausea). CONCLUSIONS: Duloxetine showed an indication of efficacy in the treatment of pain in patients with suspected SOD, but adverse events limited its use. These preliminary, open-label results justify definitive placebo-controlled trials.

Safety data on 19 vehicles for use in 1 month oral rodent pre-clinical studies: administration of hydroxypropyl-ß-cyclodextrin causes renal toxicity.

Potential new drugs are assessed in pre-clinical in vivo studies to determine their safety profiles. The drugs are formulated in vehicles suitable for the route of administration and the physicochemical properties of the drug, aiming to achieve optimal exposure in the test species. The availability of safety data on vehicles is often limited (incomplete data, access restricted/private databases). Nineteen potentially useful vehicles that contained new and/or increased concentrations of excipients and for which little safety data have been published were tested. Vehicles were dosed orally once daily to HanWistar rats for a minimum of 28 days and a wide range of toxicological parameters were assessed. Only 30% (w/v) hydroxypropyl-ß-cyclodextrin was found unsuitable owing to effects on liver enzymes (AST, ALT and GLDH), urinary volume and the kidneys (tubular vacuolation and tubular pigment). 20% (v/v) oleic acid caused increased salivation and hence this vehicle should be used with caution. As 40% (v/v) tetraethylene glycol affected urinary parameters, its use should be carefully considered, particularly for compounds suspected to impact the renal system and studies longer than 1 month. There were no toxicologically significant findings with 10% (v/v) dimethyl sulphoxide, 20% (v/v) propylene glycol, 33% (v/v) Miglyol®812, 20% (w/v) Kolliphor®RH40, 10% (w/v) Poloxamer 407, 5% (w/v) polyvinylpyrrolidone K30 or 10% (v/v) Labrafil®M1944. All other vehicles tested caused isolated or low magnitude effects which would not prevent their use. The aim of sharing these data, including adverse findings, is to provide meaningful information for vehicle selection, thereby avoiding repetition of animal experimentation.

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.

Endoscope storage time: assessment of microbial colonization up to 21 days after reprocessing.

BACKGROUND: Insufficient data exist for how long endoscopes can be stored after reprocessing. Concern about possible microbial colonization has led to various recommendations for reprocessing intervals among institutions, with many as short as 5 days. A significant cost savings could be realized if it can be demonstrated that endoscopes may be stored for as long as 21 days without risk of clinically significant contamination. OBJECTIVE: To demonstrate whether flexible endoscopes may be stored for as long as 21 days after reprocessing without colonization by pathogenic microbes. DESIGN: Prospective, observational study. SETTING: Tertiary care center. ENDOSCOPES: Four duodenoscopes, 4 colonoscopes, and 2 gastroscopes. INTERVENTION: Microbial testing of endoscope channels. MAIN OUTCOME MEASUREMENTS: Culture results at days 0, 7, 14, and 21. RESULTS: There were 33 positive cultures from 28 of the 96 sites tested (29.2% overall contamination rate). Twenty-nine of 33 isolates were typical skin or environmental contaminants, thus clinically insignificant. Four potential pathogens were cultured, including Enterococcus, Candida parapsilosis, α-hemolytic Streptococcus, and Aureobasidium pullulans; all were likely clinically insignificant as each was only recovered at 1 time point at 1 site, and all grew in low concentrations. There were no definite pathogenic isolates. LIMITATIONS: Single center. CONCLUSION: Endoscopes can be stored for as long as 21 days after standard reprocessing with a low risk of pathogenic microbial colonization. Extension of reprocessing protocols to 21 days could effect significant cost savings.