Once in a Bile - the Incidence of Bile Reflux Post-Bariatric Surgery.

PURPOSE: Excellent metabolic improvement following one anastomosis gastric bypass (OAGB) remains compromised by the risk of esophageal bile reflux and theoretical carcinogenic potential. No 'gold standard' investigation exists for esophageal bile reflux, with diverse methods employed in the few studies evaluating it post-obesity surgery. As such, data on the incidence and severity of esophageal bile reflux is limited, with comparative studies lacking. This study aims to use specifically tailored biliary scintigraphy and upper gastrointestinal endoscopy protocols to evaluate esophageal bile reflux after OAGB, sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB). METHODS: Fifty-eight participants underwent OAGB (20), SG (15) or RYGB (23) between November 2018 and July 2020. Pre-operative reflux symptom assessment and gastroscopy were performed and repeated post-operatively at 6 months along with biliary scintigraphy. RESULTS: Gastric reflux of bile was identified by biliary scintigraphy in 14 OAGB (70%), one RYGB (5%) and four SG participants (31%), with a mean of 2.9% (SD 1.5) reflux (% of total radioactivity). One participant (OAGB) demonstrated esophageal bile reflux. De novo macro- or microscopic gastroesophagitis occurred in 11 OAGB (58%), 8 SG (57%) and 7 RYGB (30%) participants. Thirteen participants had worsened reflux symptoms post-operatively (OAGB, 4; SG, 7; RYGB, 2). Scintigraphic esophageal bile reflux bore no statistical association with de novo gastroesophagitis or reflux symptoms. CONCLUSION: Despite high incidence of gastric bile reflux post-OAGB, esophageal bile reflux is rare. With scarce literature of tumour development post-OAGB, frequent low-volume gastric bile reflux likely bears little clinical consequence; however, longer-term studies are needed. CLINICAL TRIAL REGISTRY: Australian New Zealand Clinical Trials Registry number ACTRN12618000806268.

Disturbed colonic motility contributes to anorectal symptoms and dysfunction after radiotherapy for carcinoma of the prostate.

PURPOSE: To evaluate the role of colonic motility in the pathogenesis of anorectal symptoms and dysfunction after radiotherapy (RT) for carcinoma of the prostate. PATIENTS AND METHODS: Thirty-eight patients, median age 71 (range, 50-81) years with localized prostate carcinoma randomized to one of two radiation dose schedules underwent colonic transit scintigraphy and assessment of anorectal symptoms (questionnaire), anorectal function (manometry), and anal sphincteric morphology (endoanal ultrasound) before and at 1 month and 1 year after RT. RESULTS: Whole and distal colonic transit increased 1 month after RT, with faster distal colonic transit only persisting at 1 year. Frequency and urgency of defecation, fecal incontinence, and rectal bleeding increased 1 month after RT and persisted at 1 year. Basal anal pressures remained unchanged, but progressive reductions occurred in anal squeeze pressures and responses to increased intra-abdominal pressure. Rectal compliance decreased progressively in the patients, although no changes in anorectal sensory function ensued. Radiotherapy had no effect on the morphology of the internal and external anal sphincters. Distal colonic retention was weakly related to rectal compliance at 1 month, but both faster colonic transit and reduced rectal compliance were more frequent with increased fecal urgency. At 1 year, a weak inverse relationship existed between colonic half-clearance time and frequency of defecation, although both faster whole-colonic transit and reduced rectal compliance occurred more often with increased stool frequency. CONCLUSION: Colonic dysmotility contributes to anorectal dysfunction after RT for carcinoma of the prostate. This has implications for improving the management of anorectal radiation sequelae.

Anorectal function after three- versus two-dimensional radiation therapy for carcinoma of the prostate.

PURPOSE: To compare the effects of (three-dimensional) 3D vs. two-dimensional (2D) radiation therapy (RT) for carcinoma of the prostate on the prevalence and pathophysiology of anorectal dysfunction. METHODS AND MATERIALS: Anorectal symptoms, motility, sensory function, and anal sphincter morphology were evaluated before and up to 2 years after randomly assigned hypofractionated vs. conventionally fractionated RT in 67 patients (median age, 69 years; range, 54-82 years) with localized prostate carcinoma, using either a 3D (n = 29) or 2D (n = 38) treatment technique. RESULTS: Anorectal symptoms increased 4 to 6 weeks after RT and persisted in both patient groups. At 2 years, abnormalities included increased stool frequency (55% vs. 53%, p = NS), urgency of defecation (72% vs. 47%, p < 0.05), fecal incontinence (28% vs. 26%, p = NS), and rectal bleeding (38% and 42%, p = NS). Anorectal motility and sensory function deteriorated after RT in both groups with reductions in basal anal pressures, anal pressures in response to squeeze, rectal compliance, and rectal volumes associated with the desire to defecate. External but not internal sphincter thickness changed in the treatment groups although in different directions. However no differences in motility or sensory function were detected between the groups. Baseline anorectal motility but not treatment technique and the hypofracionated schedule were of independent prognostic significance for anorectal motor dysfunction and rectal bleeding respectively at 2 years. CONCLUSION: The prevalence and pathophysiology of anorectal dysfunction 2 years after RT for prostate carcinoma was largely independent of the treatment techniques used in this study.

Scintigraphic imaging of experimental colitis with technetium-99m-infliximab in the rat.

The radiolabeled monoclonal antibody (99m)Tc-infliximab was assessed as an inflammation imaging agent in a rat colitis model in comparison with (99m)Tc-tin colloid-labeled-leucocytes. (99m)Tc-infliximab and (99m)Tc-tin fluoride colloid-labeled-leucocytes were administered to (n>3) rats previously exposed to 2,4,6-trinitrobenzenesulfonic acid by rectal instillation. Whole body scintigraphic images were acquired and physiological organ assays were performed to obtain quantitative data. Histological examination of colon samples was performed to assess the site and severity of the colitis. In the inflamed colon, (99m)Tc-infliximab resulted in inflamed target (T) to control (C) colon tracer uptake ratios of 2.7 +/- 1.0 (n=5) and 2.6 +/- 0.3 (n=5) at 1 and 4 h post tracer injection respectively. (99m)Tc-leucocytes gave higher ratios of 19.5 +/- 9.9 (n=3) and 41.2 +/- 16.1 (n=5) respectively. (99m)Tc-leucocytes gave higher ratios of 19.5 +/- 9.9 and 41.2 +/- 16.1 at the corresponding time points. (99m)Tc-infliximab accumulated at sites of inflammation in this rat model but not due to a specific tumor necrosis factor-alpha binding mechanism. Although the tracer uptake was lower than radioactive leucocytes, this easily prepared (99m)Tc-monoclonal antibody may have some advantages in imaging inflammatory bowel disease in humans based on its biological activity.