Evaluation of abdominal gas by plain abdominal radiographs

Our aim was to determine the reliability of plain abdominal radiographs for the evaluation of abdominal gas content in patients with functional digestive symptoms. 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. 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. Plain abdominal radiographs have limited value for the evaluation of abdominal gas volume in patients with functional gut disorders. Example of three-dimensional reconstruction of abdominal CT scan showing intestinal gas. Plain AP projection (scout view) of the same scan. Relation between objective values of intestinal gas, measured by a validated CT technique in patients with functional gut disorders, and the subjective estimation of gas volumes on plain AP projection of the same CT scans (scout views) by 48 physicians. Individual estimations of 60 images are shown. CONCLUSION: The volumes of abdominal gas were grossly misestimated in the scout views, indicating that plain abdominal radiographs have no value for the evaluation of intestinal 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 P2Y 1 receptors, therefore this receptor plays an important role in regulation of gut motility. Recently, BPTU was developed as a negative allosteric modulator of the P2Y 1 receptor. Accordingly, the aim of this study was to assess the effect of BPTU on purinergic neurotransmission in pig and human gastrointestinal tissues. Methods: Ca 2+ imaging in tSA201 cells that express the human P2Y 1 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 Ca 2+ 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 (EC 50 = 6 µmol L −1) and colon (EC 50 = 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 ADPβS 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 P2Y 1 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

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