William G. Paterson

Anecdotal reports suggest that access to pH/motility testing is problematic in Canada, but to date there is little data documenting this. To assess the volume and accessibility of motility lab testing in Canada. The CNN developed a questionnaire directed at the scope, volume and accessibility of pH/motility testing in Canadian labs. Fifty-three labs were identified using lists provided by companies that supply pH/motility recording equipment in Canada. Of these, 12 labs were excluded (10 had incorrect or absent contact information, 1 had recently closed and 1 had just opened). Questionnaires were sent in early 2020 to the remaining 41 labs, and respondents were asked to use data from their last fiscal year pre-pandemic. 26 completed questionnaires were returned (i.e., 63% response rate, but representing ~ 51% of active labs): 23 adult units (7 community, 15 academic and 1 private) and 3 academic pediatric units. Of the adult units, 6 performed studies in children <12 yrs old. All 3 pediatric units provided both esophageal and anorectal high-resolution manometry (HRM) and pH/Impedance recording, with wait times of < 3 months. All 23 adult labs provided esophageal HRM, but just 50% performed anorectal manometry and only 3 anorectal manometry with biofeedback. Ambulatory pH/Impedance was performed in all but 1 adult unit. 15 of 23 adult centres reported access to colon transit studies and only one performed colonic manometry. No units performed antroduodenal manometry. Five units offered Bravo wireless pH recording and 4 performed ENDOFLIP. In adult units, the median number of procedures per year were as follows: esophageal HRMs - 278 (range: 50–1140); pH/impedance - 225 (range: 40–634); anorectal manometry - 90 (range: 10–450). Corresponding median wait times in months were as follows: esophageal HRM - 4 (range: 0.5–14); pH/Impedance - 4.5 (range: 0.5–14); anorectal manometry - 4.6 (range: 2–9). Only 6 of the 23 adult units met recommended wait time targets of <2 months. Testing was performed by a nurse in ~ 80% of centres, while testing was done by technicians in 2 units and physicians in 3 units. 8 units accepted referrals from primary care physicians, whereas the remainder only accepted specialist referrals. 50% screened referrals for appropriateness and restricted access accordingly. The scope of motility and pH testing across Canada is variable, with lower GI testing lacking in many regions. Wait times vary significantly across labs and the majority of centres exceed recommended limits of 2 months. The reasons underlying the identified limitations to pH/motility testing access warrant further study. None

Dysphagia is a common referral to gastroenterology with both benign and malignant etiologies. There is a lack of studies regarding its clinical assessment, complications and outcomes in Canada. To evaluate the assessment and outcomes of secondary and tertiary level dysphagia referrals in adult patients. We conducted a retrospective analysis of 98 consecutive adult patients who were initially referred for dysphagia to the Division of Gastroenterology at the Kingston Health Sciences Centre in 2015. Chart reviews were performed to assess demographics, characteristics of dysphagia, time for clinical assessment and outcomes. Of the referred patients, 19 did not present for their clinic appointment. The majority of patients (60%) were >60 yrs old with an equal distribution of male and female patients. In the assessed patients, reflux was the most common etiology (55.5%) followed by oropharyngeal causes (13.5%) and motility disorders (12%). Only 3 patients of the cohort were diagnosed with esophageal cancer, 2 of whom had metastasis at the time of presentation. Time from referral to clinical assessment was >12 weeks in 55%. For the patients diagnosed with malignancy, 2 were assessed within of 2 weeks while the third patient was assessed and endoscoped at 12 weeks. In patients sent for endoscopy, 28% had an endoscopy > 12 weeks after assessment. Manometry was performed in 18% of the patients assessed. Information was available on the course of the dysphagia in 65 patients. Dysphagia had resolved or improved in 83%, remained unchanged in 14% and worsened in 3%. Reflux-related dysphagia was by far the most common cause of dysphagia in this referral cohort. Wait times for clinical assessment greatly exceeded current CAG recommendations in the majority. Given current resource constraints, this highlights the need for improved referral information and patient care pathways in the management of patients referred with dysphagia. None

Background: The etiology of noncardiac chest pain (NCCP) is poorly understood. Some evidence suggests that it may be related to sustained esophageal contractions (SECs) of longitudinal smooth muscle. This study attempts to evaluate whether SECs play a role in symptom production in NCCP patients.Methods: This was a prospective double‐blind study comparing NCCP patients to healthy controls. Subjects underwent high‐resolution esophageal manometry followed by infusions of normal saline and 0.1N hydrochloric acid into the esophagus. Pain intensity was recorded during each minute of the infusion using a visual analog scale between 0 and 10. Two blinded investigators measured the esophageal length at the end of the saline and acid infusion periods as well as the point at which esophageal shortening began using the computer based manometry software.Key Results: Seventeen NCCP patients and 16 controls completed the study. 64% of study subjects demonstrated esophageal shortening in response to acid infusion with mean shortening of 0.4 ± 0.54 cm. The mean decrease in esophageal length with acid was similar between the groups (1.9% ± 2.6% for NCCP patients vs 1.7% ± 2.4% for controls, P = .82). There was no correlation between pain onset and esophageal shortening.Conclusions and Inferences: NCCP patients did not appear to have an exaggerated esophageal shortening response to intraluminal acid. As well, there was poor temporal correlation between esophageal shortening and symptoms. Thus, acid‐induced SECs may not play a significant role in pain production in NCCP patients.

Patients with eosinophilic esophagitis (EoE) present with mechanical type dysphagia. Barium esophagrams occasionally demonstrate focal strictures or multiple concentric rings. Diffuse narrowing has also been reported but may be difficult to recognize because of lack of normative data. The aim of this study is to assess esophageal diameters at multiple sites in healthy controls in comparison with EoE patients. A standardized barium swallow was performed in 22 healthy male volunteers without esophageal symptoms and compared with 10 untreated EoE patients. A radiopaque ruler attached at the subject’s back was used to measure maximal esophageal diameter at three esophageal sites by a blinded observer. Peak intraepithelial eosinophil counts and Mayo Dysphagia Questionnaire scores were correlated to esophageal diameters in EoE patients. Two of 10 EoE patients had areas of focal narrowing on barium Xray. Esophageal diameters were significantly less at all three esophageal sites in EoE patients compared with controls. Using a total esophageal diameter score (i.e., sum of the three diameters) to establish the 95th percentile for minimal diameter in controls, four of 10 EoE patients fell below the normal range. There was no significant correlation between esophageal diameters, peak eosinophil counts and any of the Mayo Dysphagia Questionnaire severity scores. Patients with EoE have a diffusely narrow esophagus in comparison to healthy controls, and this abnormality may not be appreciated without using appropriate normative data.

Background Screening sigmoidoscopy is effective in reducing mortality from colorectal cancer. In 2009, Cancer Care Ontario (CCO) launched a nurse-performed screening flexible sigmoidoscopy program at Hotel Dieu Hospital, Kingston, Ontario. Prior to this program, there was a pilot sigmoidoscopy screening program by gastroenterologists in a similar average risk cohort. Aim To compare neoplasia detection rates and associated costs of screening sigmoidoscopy performed by nurses and gastroenterologists. Method A retrospective chart review was conducted on flexible sigmoidoscopies performed as part of two average risk screening programs performed by gastroenterologists and nurse-endoscopists. Detected polyps were categorized as hyperplastic, low-risk adenomas or high-risk adenomas. Average cost per procedure was estimated based on physician fee for service charges, nurse wage and benefits, physician supervisory fees, pathology costs and administrative expenses. Results There were 538 procedures performed by nurses and 174 by physicians. Adenomas were detected in 18% of nurse-performed procedures versus 9% in physician-performed procedures (p=0.003), with the higher adenoma detection rate restricted to low risk adenomas. One cancer was found in the physician group. Seven physicians performed the 174 sigmoidoscopies, with one physician performing the majority. This physician’s adenoma detection rate was 4.5%, whereas detection rate for the remaining physicians combined was 16.5%. Nurses biopsied more polyps per case (0.96 versus 0.18). Average estimated cost per case was greater for nurses ($387.54 versus $309.37). Conclusion Well-trained nurse-endoscopists can provide an effective service for colorectal cancer screening, but as currently structured in Ontario, the associated cost is higher for nurse-performed procedures.

In 2007, Ontario launched a colon cancer screening program for average-risk individuals based on biennial fecal occult blood tests (FOBTs) on three fecal samples, followed by colonoscopy for individuals who tested positive. To determine whether >1 positive screening FOBT was predictive of finding advanced neoplasia at colonoscopy. A retrospective chart review of outpatient colonoscopic procedures performed at Hotel Dieu Hospital (Kingston, Ontario) in the first two years of the colon cancer screening program was conducted, focusing on endoscopic and pathological findings. Of 5556 individuals undergoing colonoscopy, 346 were referred for positive FOBT. Overall, 41 (11.8%) patients with a positive FOBT had colon cancer. In 16 (4.6%) cases, the number of positive FOBTs was not reported. For the 330 individuals in whom the number of positive tests was specified, 198, 71 and 61 cases had one, two and three positive results, respectively. Cancer was found at colonoscopy in 11 (5.6%), 11 (15.5%) and 18 (29.5%) of individuals with one, two and three positive FOBT results, respectively (OR 3.0 [95% CI 1.2 to 7.3] and 6.5 [95% CI 2.8 to 15.0] for two or three positive FOBTs compared with one; P=0.015 and P1 cm in diameter, villous component and/or high-grade dysplasia) were found in 41 (20.8%), 29 (42.0%) and 25 (41.0%) individuals with one, two and three positive FOBTs, respectively (OR 2.8 [95% CI 1.5 to 5.0] and 2.4 [95% CI 1.3 to 4.5] for two or three positive FOBTs compared with one; P=0.001 and P=0.006, respectively). The diagnostic yield of colonoscopy varied directly with the number of positive FOBTs. This information may be useful in assigning scheduling priority for patients with positive FOBTs.

The following on esophageal disease provides updated information the mucosal defense against acid and acid–pepsin injury; the roles of platelet activating factor, mast cells, proinflammatory cytokines, and chemokines in inflammation; differences and similarities in erosive and nonerosive esophagitis; acid and vanilloid receptors in esophageal mucosa; and bile acid receptors in esophageal epithelium.

Long wait times for health care have become a significant issue in Canada. As part of the Canadian Association of Gastroenterology’s Human Resource initiative, a questionnaire was developed to survey patients regarding wait times for initial gastroenterology consultation and its impact. A total of 916 patients in six cities from across Canada completed the questionnaire at the time of initial consultation. Self-reported wait times varied widely, with 26.8% of respondents reporting waiting less than two weeks, 52.4% less than one month, 77.1% less than three months, 12.5% reported waiting longer than six months and 3.6% longer than one year. One-third of patients believed their wait time was too long, with 9% rating their wait time as ‘far too long’; 96.4% believed that maximal wait time should be less than three months, 78.9% believed it should be less than one month and 40.3% believed it should be less than two weeks. Of those working or attending school, 22.6% reported missing at least one day of work or school because of their symptoms in the month before their appointment, and 9.0% reported missing five or more days in the preceding month. A total of 20.2% of respondents reported being very worried about having a serious disease (ie, scored 6 or higher on 7-point Likert scale), and 17.6% and 14.8%, respectively, reported that their symptoms caused major impairment of social functioning and with the activities of daily living. These data suggest that a significant proportion of Canadians with digestive problems are not satisfied with their wait time for gastroenterology consultation. Furthermore, while awaiting consultation, many patients experience an impaired quality of life because of their gastrointestinal symptoms.

To address the controversy surrounding the role of interstitial cells of Cajal (ICC) in nitrergic neurotransmission to gastrointestinal smooth muscle, circular smooth muscle from the lower esophageal sphincter (LES) of W/W^vwild-type and mutant (ICC-deficient) mice were studied by using intracellular and tension recordings in vitro. Resting membrane potential was more negative, and the spontaneous unitary potentials diminished in mutant mice. In wild-type mice, nerve stimulation induced a biphasic inhibitory junction potential (IJP) consisting of a fast initial IJP followed by a long-lasting slow IJP (LSIJP). The IJP was markedly impaired in a significant proportion of mutant mice, whereas in others it was normal. Pharmacological studies in the mice with markedly impaired IJPs revealed that cholinergic and purinergic components of the nerve-mediated responses appeared intact. In wild-type mice, caffeine hyperpolarized smooth muscle cells, inhibited the initial fast IJP, and completely abolished the LSIJP. In mutant mice, caffeine depolarized smooth muscle cells and abolished the impaired LSIJP but did not affect the initial fast IJP. Immunohistochemical staining for c-Kit confirmed deficiency of ICC in mutant mice with a normal nitrergic IJP. Rings of LES circular smooth muscle from W/W^vmutant mice generated significantly less spontaneous tone than controls. When tone was restored with carbachol, normal nitrergic LES relaxation was recorded. These data suggest that 1) there is significant variability in the generation of nitrergic neurotransmission in the LES of W/W^vmutant mice, whereas purinergic and cholinergic neurotransmission are intact; 2) the altered nitrergic responses appear to be associated with abnormal Ca²⁺-dependent signaling initiated by spontaneous Ca²⁺release from sarcoplasmic reticulum in smooth muscle cells; and 3) c-Kit-positive ICC are not essential for nitrergic neurotransmission in mouse LES smooth muscle.