Low risk of new dysplastic lesions in an inflammatory bowel disease population study with dye chromoendoscopy.

Background and study aims Rates of new dysplastic lesions or cancer progression after first dye chromoendoscopy in the era of high-definition endoscopy have yet to be determined. Patients and methods A multicenter, population-based, retrospective cohort study was performed in seven hospitals in Spain. Patients with inflammatory bowel disease and fully resected (R0) dysplastic colon lesions under surveillance with high-definition dye-based chromoendoscopy were sequentially enrolled between February 2011 and June 2017, with a minimum endoscopic follow-up of 36 months. The aim was to assess the incidence of developing more advanced metachronous neoplasia by analyzing possible associated risk factors. Results The study sample included 99 patients and 148 index lesions (145 low-grade dysplasia lesions and three high-grade dysplasia [HGD] lesions with a mean follow-up of 48.76 months [IQR: 36.34-67.15]). The overall incidence of new dysplastic lesions was 0.23 per 100 patient-years, 1.15 per 100 patients at 5 years and 2.29 per 100 patients at 10 years. A history of dysplasia was associated with a higher risk of developing any grade of dysplasia during follow-up ( P  = 0.025), whereas left colon lesions were associated with a lower risk ( P  = 0.043). The incidence of more advanced lesions at 1 year and 10 years was 1 % and 14 % respectively, with lesion size > 1 cm being a risk factor ( P  = 0.041). One of the eight patients (13 %) with HGD lesions developed colorectal cancer during follow-up. Conclusions The risk of dysplasia progressing to advanced neoplasia and, specifically, the risk of new neoplastic lesions after endoscopic resection of colitis-associated dysplasia, are both very low.

Evaluation of abdominal gas by plain abdominal radiographs.

BACKGROUND: Our aim was to determine the reliability of plain abdominal radiographs for the evaluation of abdominal gas content in patients with functional digestive symptoms. METHODS: Abdominal CT scan scout views, mimicking a conventional plain abdominal radiograph, were obtained from 30 patients both during episodes of abdominal distension and basal conditions. Physicians (n = 50) were instructed to rate the estimated volume of gas in the 60 images presented in random sequence using a scale graded from 0 to ≥600 ml. KEY RESULTS: The gas volumes estimated in the scout views differed from those measured by CT by a median of 90 (95% CI 70-102) ml, and the misestimation was not related to the absolute volume in the image. The accuracy of the observers, measured by their mean misestimation, was not related to their specialty or the training status (misestimation by 96 (95% CI 85-104) ml in staff vs 78 (70-106) ml in residents; p = 0.297). The accuracy was independent of the order of presentation of the images. Gas volume measured by CT in the images obtained during episodes of abdominal distension differed by a median of 39 (95% CI 29-66) ml from those during basal conditions, and this difference was misestimated by a median of 107 (95% CI 94-119) ml. The accuracy of these estimations was not related to the absolute gas volumes (R = -0.352; p < 0.001) or the magnitude of the differences. CONCLUSIONS & INFERENCES: Plain abdominal radiographs have limited value for the evaluation of abdominal gas volume in patients with functional gut disorders.

Different responses of the blockade of the P2Y1 receptor with BPTU in human and porcine intestinal tissues and in cell cultures.

BACKGROUND: Gastrointestinal smooth muscle relaxation is accomplished by activation of P2Y1 receptors, therefore this receptor plays an important role in regulation of gut motility. Recently, BPTU was developed as a negative allosteric modulator of the P2Y1 receptor. Accordingly, the aim of this study was to assess the effect of BPTU on purinergic neurotransmission in pig and human gastrointestinal tissues. METHODS: Ca2+ imaging in tSA201 cells that express the human P2Y1 receptor, organ bath and microelectrodes in tissues were used to evaluate the effects of BPTU on purinergic responses. KEY RESULTS: BPTU concentration dependently (0.1 and 1 µmol L-1 ) inhibited the rise in intracellular Ca2+ evoked by ADP in tSA201 cells. In the pig small intestine, 30 µmol L-1 BPTU reduced the fast inhibitory junction potential by 80%. Smooth muscle relaxations induced by electrical field stimulation were reduced both in pig ileum (EC50  = 6 µmol L-1 ) and colon (EC50  = 35 µmol L-1 ), but high concentrations of BPTU (up to 100 µmol L-1 ) had no effect on human colonic muscle. MRS2500 (1 µmol L-1 ) abolished all responses. Finally, 10 µmol L-1 ADPßS inhibited spontaneous motility and this was partially reversed by 30 µmol L-1 BPTU in pig, but not human colonic tissue and abolished by MRS2500 (1 µmol L-1 ). CONCLUSIONS & INFERENCES: BPTU blocks purinergic responses elicited via P2Y1 receptors in cell cultures and in pig gastrointestinal tissue. However, the concentrations needed are higher in pig tissue compared to cell cultures and BPTU was ineffective in human colonic tissue.

Even non-experts identify non-dysplastic lesions in inflammatory bowel disease via chromoendoscopy: results of a screening program in real-life.

Background and study aims Chromoendoscopy with targeted biopsy is the technique of choice for colorectal cancer screening in longstanding inflammatory bowel disease. We aimed to analyze results of a chromoendoscopy screening program and to assess the possibility of identifying low-risk dysplastic lesions by their endoscopic appearance in order to avoid histological analysis. Materials and methods We retrospectively reviewed chromoendoscopies performed between February 2011 and June 2017 in seven Spanish hospitals in a standardized fashion. We analyzed the findings and the diagnostic yield of the Kudo pit pattern for predicting dysplasia. Results A total of 709 chromoendoscopies (569 patients) were reviewed. Median duration of disease was 16.7 years (SD 8.1); 80.4 % had ulcerative colitis. A total of 2025 lesions (3.56 lesions per patient) were found; two hundred and thirty-two lesions were neoplastic (11.5 %) (223 were LGD (96.1 %), eight were HGD (3.4 %), and one was colorectal cancer (0.5 %). The correlation between dysplasia and Kudo pit patterns predictors of dysplasia (≥ III) was low, with an area under the curve of 0.649. Kudo I and II lesions were correctly identified with a high negative predictive value (92 %), even by non-experts. Endoscopic activity, Paris 0-Is classification, and right colon localization were risk factors for dysplasia detection, while rectum or sigmoid localization were protective against dysplasia. Conclusions Chromoendoscopy in the real-life setting detected 11 % of dysplastic lesions with a low correlation with Kudo pit pattern. A high negative predictive value would prevent Kudo I and, probably, Kudo II biopsies in the left colon, reducing procedure time and avoiding complications.

Timing of Thiopurine or Anti-TNF Initiation Is Associated with the Risk of Major Abdominal Surgery in Crohn's Disease: A Retrospective Cohort Study.

INTRODUCTION: Early stages of Crohn's disease [CD] are predominantly inflammatory and early treatment could be useful to change the natural history of CD. We aimed to evaluate the impact of early treatment in our cohort of CD patients. METHODS: We retrospectively reviewed clinical records of all CD patients at our centre who have received immunomodulators. Time from diagnosis to first CD-related major abdominal surgery or end of follow-up was considered. Dates of diagnosis, of starting immunomodulators (thiopurines / anti-tumour necrosis factor [TNF]), and of the first CD-related surgery when appropriate were collected. RESULTS: Of 422 patients who received thiopurines, 189 operated patients started thiopurines after a median of 117 months (interquartile range [IQR] 44-196) since diagnosis; non-operated patients, after a median of 30 months [IQR 6-128], p < 0,005. Odds ratio [OR] for surgery was 1.006 (95% confidence interval [CI]1.004-1008) for each month of delay in starting thiopurines. Among 272 patients who received anti-TNFs, 137 operated patients started anti-TNFs after a median of 166 months [IQR 90-233] since diagnosis; non-operated patients after a median of 59 months [IQR 14-162]; p < 0,005. OR for surgery was 1.008 [95% CI 1.005-1.010] for each month of delay in starting anti-TNFs. Among 467 patients who received thiopurines and/or anti-TNF, 210 operated patients started any immunomodulator after a median of 120 months [IQR 48-197] since diagnosis and non-operated patients after a median of 30 months [IQR 6-126], p < 0,005. OR for surgery was 1.008 [95% CI 1.005-1.010] for each month of delay in starting immunomodulators. CONCLUSIONS: In our experience, time between diagnosis and thiopurine or anti-TNF initiation was associated with the risk of major abdominal surgery in Crohn's disease.