ERCP for the initial management of malignant biliary obstruction - real world data on 596 procedures.

AIMS: To evaluate outcomes of ERCP as first-line management in patients with malignant biliary obstruction (MBO) of all causes and stages, reflecting a real-life setting. METHODS: Retrospective observational study of patients with ERCP as the first-line management of MBO at Oslo University Hospital between 2015 and 2021. Primary outcome measure was a ≥ 50% decrease from the pre-procedural bilirubin within 30 days after ERCP. Secondary outcome measures were technical success of ERCP, complications and overall mortality. RESULTS: A total of 596 patients were included, median age 70 years. ASA score was ≥ III in 67% of patients. The most common cancers causing MBO were pancreatic cancer (52%), metastatic lesions (20%) and cholangiocarcinoma (16%). The primary outcome measure was achieved in 62% of patients. With endoscopic access, overall technical success was 80% with 85% for the distal extrahepatic group, 71% for the perihilar, 40% for the intrahepatic and 53% for multiple level MBOs. Reinterventions were performed in 27% of the patients. Complications occurred in 15% of the patients, including post-ERCP pancreatitis in 9%. Most complications were of minor/moderate severity (81%). Overall mortality was 33% within the first 90 days. Patients deceased by the end of the study period (83%) had median survival of 146 days (range 1-2,582 days). CONCLUSIONS: ERCP has a high rate of clinical effect and technical success in the management of both distal extrahepatic and perihilar MBO. Our data indicate that ERCP is a valid option in the first-line management of MBO.

Pancreas transplant rejection episodes are not revealed by biopsies of the donor duodenum in a prospective study with paired biopsies.

The surgical technique with duodeno-duodenal enteroanastomosis of pancreas transplants allows for representative endoscopic ultrasound-guided needle biopsies of the donor duodenum and the pancreas graft. We assessed whether histological findings in transplanted donor duodenal biopsies can indicate rejection in the transplanted pancreas. Since September 2012, a duodeno-duodenal enteroanastomosis has been the default technique for pancreas transplantations at our center. In 67 recipients we prospectively examined 113 endoscopic ultrasound-guided procedures with representative biopsies from the duodenum grafts and the pancreas grafts (97 per protocol and 16 on indication). All graft biopsies were evaluated according to established rejection criteria. A total of 22 biopsy-proven pancreas rejections were detected, with 2 matching duodenal biopsies showing rejection. This gives a sensitivity of 9% for detection of a pancreas rejection by duodenal biopsies. The other matching duodenal biopsies were either normal (n = 13) or indeterminate (n = 7). Rejection of the donor duodenum was found in only 6/113 biopsies, with 2 concurrent pancreas rejections. In conclusion, the donor duodenum is not a useful reporter organ for rejection in the pancreas graft.

Preoperative liquid gastric emptying rate does not predict outcome after fundoplication.

AIM OF THE STUDY: Preoperative gastric emptying (GE) rate in patients with gastrointestinal reflux disease (GERD) was evaluated as a predictor of outcome after antireflux surgery. METHODS AND PATIENTS: GE was assessed using radionuclide scintigraphy and a standardized meal with cow's milk. GE half time (T1/2), patient demographics and GERD symptoms including vomiting (>4days/week), retching (>4days/week), prolonged feeding time (>3h/day), and discomfort after meals were recorded pre- and postoperatively. A standardized follow-up included a 24-h pH-monitoring and an upper gastrointestinal contrast study. Of 74 patients undergoing Nissen fundoplication between 2003 and 2009, 35 underwent a preoperative GE study. The remaining 39 patients were not examined owing to volume intolerance, cow's milk intolerance or allergy, inability to lie still, or parents refusing participation. MAIN RESULTS: Median age at fundoplication was 4.9 [range 1.1-15.4] years, and follow-up time was median 4.3 [1.9-8.9] years. GERD recurred in 7 (20%) patients. Preoperative T1/2 in the seven patients with recurrent GERD was median 45 [21-87] min compared to 44 [16-121] min in the 28 patients without recurrent GERD (p=0.92). There was no significant difference between the one third of patients with the slowest GE [T1/2 54-121min] and the remaining patients [T1/2 16-49min] regarding GERD recurrence or postoperative vomiting, retching, prolonged feeding time, or discomfort after meals. CONCLUSION: Preoperative GE rate did not predict outcome after antireflux surgery, as slow GE was not associated with recurrent GERD or postoperative troublesome symptoms such as vomiting, retching, or meal discomfort.

Comparison of endoscopic based diagnosis with Helicobacter urease test for Helicobacter pylori infection.

BACKGROUND: Helicobacter pylori is an important risk factor for gastritis, peptic ulcers and gastric cancer. The prevalence in developed countries is lower than 40 % but higher than 80 % in some developing countries. It is 75 % in Ghana. The Helicobacter urease test (HUT) is performed at endoscopy and gives an accurate diagnosis. The HUT is not routinely done at our facility and presumption of H. pylori is made based on endoscopic findings and H. pylori eradication prescribed, as the incidence in the general population is presumed high. Is this endoscopic diagnosis sufficient for diagnosing and treating H. pylori? We aimed to assess the feasibility of an endoscopic based H. pylori diagnosis and its accuracy using a HUT as the gold standard in consecutive patients. METHODS: Seventy-six consecutive adult patients with dyspepsia were assessed by upper gastrointestinal endoscopy. A clinical diagnosis of H. pylori or not was made. Biopsy samples were collected for HUT. H. pylori was diagnosed if HUT was positive. The results were then compared. RESULTS: Median age of patients was 45.0 years. H. pylori prevalence detected by HUT was 51.3 % (95 % CI 40.0-63.0). Sensitivity of endoscopic diagnosis of H. pylori was 71.8 % (95 % CI 55.1-85.0) and specificity was 37.8 % (95 % CI 22.5-55.2). There was no association between clinical findings (73.7 %) and HUT (26.3 %) (OR = 0.80; [95 % CI 0.24-2.64], p = 0.682). There was also no association between endoscopic diagnosis (71.8 %) and HUT (28.2 %), (OR = 1.55; 95 % CI 0.59-4.06, p = 0.373). CONCLUSION: Helicobacter pylori infection was not as high as that published in earlier reports. The endoscopic diagnosis alone is not sufficient to make a diagnosis of H. pylori.

Papillary cannulation and sphincterotomy techniques at ERCP: European Society of Gastrointestinal Endoscopy (ESGE) Clinical Guideline

This Guideline is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). It provides practical advice on how to achieve successful cannulation and sphincterotomy at minimum risk to the patient. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was adopted to define the strength of recommendations and the quality of evidence. Main recommendations 1 ESGE suggests that difficult biliary cannulation is defined by the presence of one or more of the following: more than 5 contacts with the papilla whilst attempting to cannulate; more than 5 minutes spent attempting to cannulate following visualization of the papilla; more than one unintended pancreatic duct cannulation or opacification (low quality evidence, weak recommendation). 2 ESGE recommends the guidewire-assisted technique for primary biliary cannulation, since it reduces the risk of post-ERCP pancreatitis (moderate quality evidence, strong recommendation). 3 ESGE recommends using pancreatic guidewire (PGW)-assisted biliary cannulation in patients where biliary cannulation is difficult and repeated unintentional access to the main pancreatic duct occurs (moderate quality evidence, strong recommendation). ESGE recommends attempting prophylactic pancreatic stenting in all patients with PGW-assisted attempts at biliary cannulation (moderate quality evidence, strong recommendation). 4 ESGE recommends needle-knife fistulotomy as the preferred technique for precutting (moderate quality evidence, strong recommendation). ESGE suggests that precutting should be used only by endoscopists who achieve selective biliary cannulation in more than 80 % of cases using standard cannulation techniques (low quality evidence, weak recommendation). When access to the pancreatic duct is easy to obtain, ESGE suggests placement of a pancreatic stent prior to precutting (moderate quality evidence, weak recommendation). 5 ESGE recommends that in patients with a small papilla that is difficult to cannulate, transpancreatic biliary sphincterotomy should be considered if unintentional insertion of a guidewire into the pancreatic duct occurs (moderate quality evidence, strong recommendation).In patients who have had transpancreatic sphincterotomy, ESGE suggests prophylactic pancreatic stenting (moderate quality evidence, strong recommendation). 6 ESGE recommends that mixed current is used for sphincterotomy rather than pure cut current alone, as there is a decreased risk of mild bleeding with the former (moderate quality evidence, strong recommendation). 7 ESGE suggests endoscopic papillary balloon dilation (EPBD) as an alternative to endoscopic sphincterotomy (EST) for extracting CBD stones < 8 mm in patients without anatomical or clinical contraindications, especially in the presence of coagulopathy or altered anatomy (moderate quality evidence, strong recommendation). 8 ESGE does not recommend routine biliary sphincterotomy for patients undergoing pancreatic sphincterotomy, and suggests that it is reserved for patients in whom there is evidence of coexisting bile duct obstruction or biliary sphincter of Oddi dysfunction (moderate quality evidence, weak recommendation). 9 In patients with periampullary diverticulum (PAD) and difficult cannulation, ESGE suggests that pancreatic duct stent placement followed by precut sphincterotomy or needle-knife fistulotomy are suitable options to achieve cannulation (low quality evidence, weak recommendation).ESGE suggests that EST is safe in patients with PAD. In cases where EST is technically difficult to complete as a result of a PAD, large stone removal can be facilitated by a small EST combined with EPBD or use of EPBD alone (low quality evidence, weak recommendation). 10 For cannulation of the minor papilla, ESGE suggests using wire-guided cannulation, with or without contrast, and sphincterotomy with a pull-type sphincterotome or a needle-knife over a plastic stent (low quality evidence, weak recommendation).When cannulation of the minor papilla is difficult, ESGE suggests secretin injection, which can be preceded by methylene blue spray in the duodenum (low quality evidence, weak recommendation). 11 In patients with choledocholithiasis who are scheduled for elective cholecystectomy, ESGE suggests intraoperative ERCP with laparoendoscopic rendezvous (moderate quality evidence, weak recommendation). ESGE suggests that when biliary cannulation is unsuccessful with a standard retrograde approach, anterograde guidewire insertion either by a percutaneous or endoscopic ultrasound (EUS)-guided approach can be used to achieve biliary access (low quality evidence, weak recommendation). 12 ESGE suggests that in patients with Billroth II gastrectomy ERCP should be performed in referral centers, with the side-viewing endoscope as a first option; forward-viewing endoscopes are the second choice in cases of failure (low quality evidence, weak recommendation). A straight standard ERCP catheter or an inverted sphincterotome, with or without the guidewire, is recommended by ESGE for biliopancreatic cannulation in patients who have undergone Billroth II gastrectomy (low quality evidence, strong recommendation). Endoscopic papillary ballon dilation (EPBD) is suggested as an alternative to sphincterotomy for stone extraction in the setting of patients with Billroth II gastrectomy (low quality evidence, weak recommendation).In patients with complex post-surgical anatomy ESGE suggests referral to a center where device-assisted enteroscopy techniques are available (very low quality evidence, weak recommendation).

Edge density based automatic detection of inflammation in colonoscopy videos.

Colon cancer is one of the deadliest diseases where early detection can prolong life and can increase the survival rates. The early stage disease is typically associated with polyps and mucosa inflammation. The often used diagnostic tools rely on high quality videos obtained from colonoscopy or capsule endoscope. The state-of-the-art image processing techniques of video analysis for automatic detection of anomalies use statistical and neural network methods. In this paper, we investigated a simple alternative model-based approach using texture analysis. The method can easily be implemented in parallel processing mode for real-time applications. A characteristic texture of inflamed tissue is used to distinguish between inflammatory and healthy tissues, where an appropriate filter kernel was proposed and implemented to efficiently detect this specific texture. The basic method is further improved to eliminate the effect of blood vessels present in the lower part of the descending colon. Both approaches of the proposed method were described in detail and tested in two different computer experiments. Our results show that the inflammatory region can be detected in real-time with an accuracy of over 84%. Furthermore, the experimental study showed that it is possible to detect certain segments of video frames containing inflammations with the detection accuracy above 90%.

Randomised controlled trial of temoporfin photodynamic therapy plus chemotherapy in nonresectable biliary carcinoma--PCS Nordic study.

BACKGROUND: Photodynamic therapy (PDT) in combination with stent have shown promising results in the treatment of biliary tract cancer (BTC) in patients not suitable for surgery. Chemotherapy has been shown to improve survival in patients with local advanced and metastatic BTC. MATERIAL AND METHODS: In the current randomized trial the combination of chemotherapy and stent with and without temoporfin (Foscan) photodynamic therapy (PDT), with a primary endpoint on feasibility and safety, has been performed. Ten patients in each group. RESULTS: No serious, acute procedure-related complication related to PDT or the treatment combination was seen. The number of patients with cholangitis was equal in both groups. In the PDT group--arm A--two patients had cutaneous erythema after sun exposition, one of them with a localized blister. No neutropenic infection was seen. Quality of Life (QoL) was similar in both treatment groups. Progression free survival was numerically longer in the PDT group. CONCLUSION: The treatment combination was feasible. There was no serious complication related to PDT or the treatment combination. Number of cholangitis was equal in both groups, two abscesses were observed in the PDT group. Progression free survival was numerically longer in the PDT group.

Implementation of Endoscopic Submucosal Dissection for Gastric Lesions in Norway.

BACKGROUND AND AIMS: Endoscopic submucosal dissection is a minimal invasive method for an en bloc resection of dysplasia or early cancer in the stomach. It was developed in Japan in the 1990s, but thus far has not been widely adopted in Western countries. The aim of this study is to report from the introductory phase of gastric endoscopic submucosal dissection in a small-volume Scandinavian center. MATERIAL AND METHODS: The 15 first patients operated on with endoscopic submucosal dissection in the stomach at the University Hospital of North Norway were consecutively registered in a prospective database and evaluated as a quality assurance study. The indications for the procedures were diagnostic or therapeutic. RESULTS: Three patients had benign lesions, three had low-grade dysplasia, five had high-grade dysplasia, two had neuroendocrine tumors, and two had early gastric cancers (T1b). The R0 resection rate was 83%. One neuroendocrine tumor was directed to surgery. No recurrences have been detected after the median of 6 months, and with the exception of one delayed bleeding being treated endoscopically, no serious complications occurred. Two perforations were perioperatively closed with clips. CONCLUSION: This is the first report on gastric endoscopic submucosal dissection in Scandinavia. Preliminary results from an introductory phase indicate that endoscopic submucosal dissection for dysplasia or early gastric cancer may be conducted safely and with acceptable results even in a small-volume center, assuming that surgeons and gastroenterologists in a region direct cases to one individual who can learn this skill.

Pancreas transplantation with enteroanastomosis to native duodenum poses technical challenges--but offers improved endoscopic access for scheduled biopsies and therapeutic interventions.

To facilitate endoscopic access for rejection surveillance and stenting of the pancreas, we have abandoned the duodenojejunostomy (DJ) in favor of duodenoduodenostomy (DD) in pancreas transplantation (PTx). From September 2012 to September 2013 we performed 40 PTx with DD; 20 solitary-PTx (S-PTx) and 20 simultaneous pancreas and kidney transplantation (SPK). We compared the outcomes with results from 40 PTx-DJ (10 S-PTx and 30 SPK) from the preceding era. The DD-enteroanastomoses were performed successfully. Endoscopic pancreas biopsies (endoscopic ultrasound examination [EUS]) yielded representative material in half of the cases. One exocrine fistula was treated by endoscopic stenting. PTxs-DD were associated with a higher rate of thrombosis compared to PTx-DJ (23% vs. 5%) and reoperations (48% vs. 30%), as well as inferior graft survival (80% vs. 88%). Time on waiting list, HLA A + B mismatches and reoperations were associated with graft loss. Only recipient age remained an independent predictor of patient death in multivariate analysis. PTx-DD showed a higher rate of thrombosis and inferior results, but facilitated a protocol biopsy program by EUS that was feasible and safe. Given that technical difficulties can be solved, the improved endoscopic access might confer long-term benefits, yet this remains to be proven.

Patterns and predictive factors of complications after endoscopic retrograde cholangiopancreatography.

BACKGROUND: With an increased use of magnetic resonance imaging, the indications for endoscopic retrograde cholangiopancreatography (ERCP) have changed. Consequently, the patterns and factors predictive of complications after ERCP performed during current routine clinical practice are not well known. METHODS: A prospective multicentre cohort study was undertaken in 11 Norwegian hospitals. Complications and mortality within 30 days after ERCP were analysed by univariable and multivariable regression analysis. RESULTS: There were 2808 ERCP procedures, of which 2573 (91·6 per cent) were therapeutic. More than half of the patients were aged 70 years or more. Common bile duct cannulation was achieved in 2557 procedures (91·1 per cent). Complications occurred in 327 (11·6 per cent) of the procedures, including cholangitis in 100 (3·6 per cent), pancreatitis in 88 (3·1 per cent), bleeding in 66 (2·4 per cent), perforation in 25 (0·9 per cent) and cardiovascular-respiratory events in 32 (1·1 per cent). In the multivariable regression analysis, older age, increasing American Society of Anesthesiologists fitness score, centre ERCP volumes of more than 150 procedures annually and precut sphincterotomy were predictive factors for severe complications. The overall 30-day mortality rate was 2·2 per cent (63 patients), with a procedure-related mortality rate of 1·4 per cent (39 patients). Malignancy was diagnosed in 46 (73 per cent) of the patients who died. CONCLUSION: ERCP is a procedure with considerable risk for complications. Morbidity and mortality are related to patient age and co-morbidity, as well as hospital volume of ERCP procedures and the type of intervention.

European guidelines for quality assurance in colorectal cancer screening and diagnosis: overview and introduction to the full supplement publication.

Population-based screening for early detection and treatment of colorectal cancer (CRC) and precursor lesions, using evidence-based methods, can be effective in populations with a significant burden of the disease provided the services are of high quality. Multidisciplinary, evidence-based guidelines for quality assurance in CRC screening and diagnosis have been developed by experts in a project co-financed by the European Union. The 450-page guidelines were published in book format by the European Commission in 2010.  They include 10 chapters and over 250 recommendations, individually graded according to the strength of the recommendation and the supporting evidence. Adoption of the recommendations can improve and maintain the quality and effectiveness of an entire screening process, including identification and invitation of the target population, diagnosis and management of the disease and appropriate surveillance in people with detected lesions. To make the principles, recommendations and standards in the guidelines known to a wider professional and scientific community and to facilitate their use in the scientific literature, the original content is presented in journal format in an open-access Supplement of Endoscopy. The editors have prepared the present overview to inform readers of the comprehensive scope and content of the guidelines.

Incontinence after colonoscopy--an unrecognized and preventable problem. A cross-sectional study from the Gastronet quality assurance program.

BACKGROUND: Colonoscopy requires insufflation of gas for visualization of the bowel wall. Worldwide, this is usually done using air. The aim of the present study was to assess the risk of postcolonoscopy incontinence, and to investigate whether insufflation of CO2 instead of air may reduce this risk, since it is easily absorbed through the bowel mucosa. METHODS: This is a prospective multicenter study of colonoscopy patients undergoing bowel insufflation using air or CO2. A successive series of colonoscopies were reported to a national quality assurance program in Norway between January and December 2009 from 21 endoscopy centers with varying insufflation practices. The study comprised 7812 patients aged 18 years or older who were referred for outpatient colonoscopy. Of these, 5015 underwent colonoscopy performed using air and 2797 colonoscopy using CO2 insufflation. RESULTS: Patient-reported incontinence up to 24 h after colonoscopy was compared using binary logistic regression analysis for the type of gas used for insufflation. The air and CO2 patient groups were comparable with regard to age, sex, indication for colonoscopy, and sedation practice. Incontinence was reported by 336 out of 7812 patients (4.3%). Incontinence was significantly less frequent in the CO2 group than in the air group [2.1% versus 5.5%; adjusted odds ratio (OR) 0.38; 95%CI 0.28-0.50; P < 0.001]. Female patients had a higher risk of incontinence than men (adjusted OR 1.77; 95% CI 1.39-2.24; P < 0.001). CONCLUSION: About every 20th patient undergoing colonoscopy using standard air insufflation experiences postexamination incontinence. This proportion can be reduced by 60% by converting from air insufflation to insufflation with the absorbable CO2.

Clinical predictors of poor outcomes among patients with nonvariceal upper gastrointestinal bleeding in Europe.

BACKGROUND: Nonvariceal upper gastrointestinal bleeding (NVUGIB) is a common medical emergency associated with substantial morbidity and mortality. Despite advances in endoscopic and pharmacological treatment during the past two decades, the incidence of mortality associated with NVUGIB has remained relatively constant. AIM: To report outcomes and predictive factors for bleeding continuation/re-bleeding and mortality of NVUGIB in clinical practice in different European countries. METHODS: This observational, retrospective cohort study (NCT00797641; ENERGIB) was conducted in Belgium, Greece, Italy, Norway, Portugal, Spain and Turkey. Eligible patients were hospitalised (new admissions or inpatients), presenting with overt NVUGIB with endoscopy from 1 October to 30 November, 2008. Patients were managed according to routine care, and data regarding bleeding continuation/re-bleeding, pharmacological treatment, surgery and mortality during 30-days after the initial bleed were collected. A multivariate analysis of clinical factors predictive of poor outcomes was conducted. RESULTS: Overall, 2660 patients (64.7% men; mean age 67.7 years) were evaluable. Significant differences across countries in bleeding continuation/re-bleeding (range: 9-15.8%) or death (2.5-8%) at 30 days were explained by clinical factors (number of comorbidities, age > 65 years, history of bleeding ulcers, in-hospital bleeding, type of lesion or type of concomitant medication). Other factors (country, size of hospital, profile of team managing the event, or endoscopic/pharmacological therapy received) did not affect these outcomes. Similar predictors were observed in patients with high-risk stigmata. CONCLUSION: Differences in the outcomes of nonvariceal upper gastrointestinal bleeding in clinical practice across some European countries are explained mainly by patient-related factors, and not by management factors.

Single- vs. double-balloon enteroscopy in small-bowel diagnostics: a randomized multicenter trial.

BACKGROUND AND STUDY AIMS: Double-balloon enteroscopy (DBE) is the first choice endoscopic technique for small-bowel visualization. However, preparation and handling of the double-balloon enteroscope is complex. Recently, a single-balloon enteroscopy (SBE) system has been introduced as being a simplified, less-complex balloon-assisted enteroscopy system. PATIENTS AND METHODS: This study was a randomized international multicenter trial comparing two balloon-assisted enteroscopy systems: DBE vs. SBE. Consecutive patients referred for balloon-assisted enteroscopy were randomized to either DBE or SBE. Patients were blinded with regard to the type of instrument used. The primary study outcome was oral insertion depth. Secondary outcomes included complete small-bowel visualization, anal insertion depth, patient discomfort, and adverse events. Patient discomfort during and after the procedure was scored using a visual analog scale. RESULTS: A total of 130 patients were included over 12 months: 65 with DBE and 65 with the SBE technique. Patient and procedure characteristics were comparable between the two groups. Mean oral intubation depth was 253 cm with DBE and 258 cm with SBE, showing noninferiority of SBE vs. DBE. Complete visualization of the small bowel was achieved in 18 % and 11 % of procedures in the DBE and SBE groups, respectively. Mean anal intubation depth was 107 cm in the DBE group and 118 cm in the SBE group. Diagnostic yield and mean pain scores during and after the procedures were similar in the two groups. No adverse events were observed during or after the examinations. CONCLUSIONS: This head-to-head comparison study shows that DBE and SBE have a comparable performance and diagnostic yield for evaluation of the small bowel.

Relationship between Fecal Content of Fatty Acids and Cyclooxygenase mRNA Expression and Fatty Acid Composition in Duodenal Biopsies, Serum Lipoproteins, and Dietary Fat in Colectomized Familial Adenomatous Polyposis Patients.

A few familial adenomatous polyposis studies have focused upon faecal sterols and bile acids but none has analysed the fecal content of fatty acids. We report here findings of an observational study on 29 colectomized familial adenomatous polyposis patients that describe the fecal content of fatty acids, and relate this to the proportions of fatty acids and levels of cyclooxygenase mRNA expression in duodenal biopsies, levels of serum lipoproteins, and diet. In the ileostomy group separately (n = 12), the fecal content of arachidonic acid was correlated negatively to the proportions of eicosapentaenoic acid and docosahexaenoic acid in duodenal biopsies. Total serum-cholesterol was negatively correlated to the fecal content of saturates and monounsaturates. The fecal palmitoleic acid/palmitic acid ratio was positively correlated to the levels of cyclooxygease-2 expression in duodenal biopsies.In the ileal-pouch-anal anastomosis group separately (n = 17), significant correlations were found between the fecal contents of oleic acid, linoleic acid, and alpha-linolenic acid, and the proportions of myristic acid, oleic acid and eicosaenoic acid in duodenal biopsies. Dietary monounsaturates were positively correlated to different fecal fatty acids. Future studies should focus on molecular mechanisms relevant to fatty acid metabolism, inflammation, and angiogenesis, in addition to nutrition.

Validation of a cholangiographic prognostic model in primary sclerosing cholangitis.

BACKGROUND AND STUDY AIMS: We previously developed a prognostic model for primary sclerosing cholangitis (PSC), which was primarily based on a cholangiographic classification of the intra- and extrahepatic biliary tree lesions. The aim of the present study was to validate the performance of this model in an external cohort. PATIENTS AND METHODS: The validation dataset consisted of patients with PSC from a single referral center in Oslo, Norway. The patients' cholangiograms were scored according to the Amsterdam classification. We then examined whether adjusting the value of the original coefficients of the predictors or adding new predictors would improve the fit of the original model in the validation cohort. In addition, we evaluated calibration (closeness between observed and expected survival) and discrimination using the concordance index. RESULTS: A total of 111 patients (mean age 35 +/- 13 years; 76 % male) were included in the validation study. Baseline clinical characteristics were comparable between the two cohorts. None of the coefficients that were re-estimated in the validation cohort differed significantly from the values of the original model. Observed and expected survival curves were in close agreement across different risk groups. Discrimination of the original model was preserved in the validation cohort: the concordance index was the same in both cohorts. CONCLUSIONS: The prognostic model showed adequate performance in an independent series of patients. Therefore, we updated the model using the data from both cohorts to provide more robust estimates of transplant-free survival for individual patients. A nomogram was constructed, which can be used to predict medium- and long-term prognosis in individual patients with PSC.