Talley, Nicholas J.

SummaryBackgroundRumination syndrome is a functional gastroduodenal disorder characterised by effortless regurgitation of recently ingested food. Emerging evidence reports duodenal eosinophilic inflammation in a subset, suggesting a shared pathophysiology with functional dyspepsia (FD).AimTo assess the clinical features of rumination syndrome and FD in a community‐based study.MethodsWe mailed a survey assessing gastrointestinal symptoms, diet and psychological symptoms to 9835 residents of Olmsted County, MN, USA in 2017‐2018; diagnostic codes were obtained from linked clinical records. The two disorders were assessed as mutually exclusive in ‘pure’ forms with a separate overlap group, all compared to a control group not meeting criteria for either. Prevalence of associations, and univariate and independent associations with predictors were assessed by logistic regression.ResultsPrevalence of rumination syndrome and FD were 5.8% and 7.1%, respectively; the overlap was 3.83‐times more likely than expected by chance. Independent predictors for rumination (odds ratio (OR), 95% confidence interval (CI)) were female gender (1.79, 1.21‐2.63), smoking (1.89, 1.28‐2.78), gluten‐free diet (1.58, 1.14‐2.19), allergic rhinitis (1.45, 1.01‐2.08) and depression (1.10, 1.05‐1.16). FD was independently associated with female gender, depression, non‐coeliac wheat sensitivity, migraine, irritable bowel syndrome and somatic symptoms. A similar reported efficacy (≥54%) of low fat or dairy‐free diets was found with both disorders (P = 0.53 andP = 1.00, respectively). The strongest independent associations with overlapping FD and rumination syndrome were a history of rheumatoid arthritis (3.93, 1.28‐12.06) and asthma (3.02, 1.44‐6.34).ConclusionRumination syndrome overlaps with FD with a shared risk factor profile, suggesting a common pathophysiology.

Serological testing for Helicobacter pylori infection is one of the diagnostic methods of choice. Various commercial kits that use different antigens have been developed, but data on their diagnostic accuracy and direct comparisons between the tests are lacking. We aimed to evaluate the sensitivity, specificity, and predictive value of three immunoglobulin G enzyme-linked immunosorbent assay kits: Pylori stat, Helico-G, and Premier H. pylori. Serum samples and gastric biopsy findings from 76 patients were evaluated. We found by using a priori cutoff values that the Pylori stat, Helico-G, and Premier kits had overall sensitivities of 96, 96, and 88%, respectively, and specificities of 94, 86, and 96%, respectively, compared with gastric biopsy findings. For 232 serum samples, the Pylori stat test and a previously validated standard serological assay on which the test was based disagreed in 3% of the cases, while for 76 samples that were tested, Helico-G and a previously validated standard assay on which it was based disagreed in 8% of the cases. The intra- and interassay precision of each of the test kits was high. We conclude that serology based on any of these commercial tests represents a reliable and valid method for the diagnosis of H. pylori whether or not highly purified antigens are used.

Enzyme-linked immunosorbent assays (ELISAs) have been developed to diagnose Helicobacter pylori infection. However, the methods are not standardized. We therefore prospectively evaluated the sensitivities and specificities of ELISAs developed in the United States and the United Kingdom in a study population comprising 41 consecutive symptomatic outpatients and 35 volunteers. At endoscopy, multiple biopsies were obtained for histology and culture and stained sections were graded for chronic gastritis, active chronic gastritis, and density of H. pylori. Serum samples were analyzed for H. pylori by ELISA. The first set of assays for immunoglobulin G (IgG) and IgA used a pool of sonicated isolates of H. pylori from five patients in the United States (antigen A). The second set of assays, developed in the United Kingdom, used three different antigens: antigen 1, an acid-extractable surface antigen; antigen 2, an acid-extractable antigen from an aflagellate variant; and antigen 3, a urease-containing fraction. Cutoff scores for positive results were determined a priori on the basis of previous serological studies. There was close agreement between histology and culture. In the study population, 36% of the individuals were H. pylori positive. The diagnostic value of the different ELISAs were highly comparable, and the crude antigens performed as well as the more purified antigens. The antigen A IgG had a sensitivity and specificity of 96 and 94%, respectively; the values for antigen 1 were 93 and 96%, respectively. The antigen A IgA and antigen 3 assays were the least sensitive tests.(ABSTRACT TRUNCATED AT 250 WORDS)

Goals and Background: Baseline impedance measured during high-resolution impedance manometry (HRIM) can distinguish patients with gastroesophageal reflux disease (GERD) from controls, presumably due to differences in esophageal acid exposure. The characteristics of regurgitation and reflux in rumination syndrome and GERD are very different, and thus we investigated whether baseline esophageal impedance would differ in these 2 patient groups compared with controls. Study: We compared 20 patients with rumination syndrome with 20 patients who had GERD and 40 controls. Baseline impedance was measured over 15 seconds during the landmark period of HRIM in all 18 impedance sensors on a HRIM catheter. Results: The mean distal baseline impedance measured in ohms during HRIM was 1336 Ω [95% confidence interval (CI)=799, 1873) in patients with GERD, 1536 Ω in rumination syndrome (95% CI=1012, 2061), and 3379 Ω in controls (95% CI=2999, 3759) (P<0.0001). Proximal impedance was significantly lower in the GERD and rumination groups compared with controls; rumination syndrome (2026; 95% CI=1493, 2559 Ω), GERD (2572; 95% CI=2027, 3118 Ω), and controls (3412; 95% CI=3026, 3798 Ω) (P<0.001). Conclusions: Baseline impedance measured during HRIM in patients with rumination syndrome is significantly lower than controls and appears similar to patients with GERD both in the proximal and distal esophagus. These findings suggest that the postprandial regurgitation in rumination syndrome alters both the distal and proximal esophageal mucosal barrier.

Goals: To evaluate agreement of MCM6-13910 with self-report of dairy sensitivity (DS) and lactose hydrogen methane breath test (LHMBT) results in subjects with irritable bowel syndrome (IBS). Background: IBS is a functional gastrointestinal disorder with symptoms including abdominal pain, variable bowel habits, and bloating. Adult patients with lactose malabsorption may present with similar symptoms. Patients with lactose malabsorption have a lactase nonpersistent (LNP) phenotype. Recent studies found 2 single nucleotide polymorphisms associated with LNP: G/A-22018 and C/T-13910. Study: Genotyping the MCM6-13910 variant of LNP in 538 IBS patients and 317 controls (without IBS). Subjects completed questionnaires pertaining to gastrointestinal problems and dietary consumption, with charts abstracted. Results: Self-reported DS was higher in IBS (45%) than controls (9.8%, odds ratio=6.46, P<0.001). The C/C-13910 genotype was similar in IBS cases and controls, 81 (15.1%) and 47 (14.8%). Among subjects reporting DS, 49 (18.0%) had the C/C genotype. Overall agreement between genotype and self-reported DS was 0.06 in IBS and 0.07 in controls. There were 20 subjects with LHMBT results; 3 had positive results, 17 were negative. LNP genotypes were found in all 3 of positive LHMBT results; 16 had negative LHMBT among the 17 who were lactase persistent. Agreement between C/C-13910 genotype and LHMBT was excellent with κ-statistic of 0.83 (0.50-1.00). Conclusions: In IBS patients, self-report of lactose intolerance are highly prevalent but are a poor indicator of underlying C/C-13910 genotype. LHMBT had excellent agreement with C/C-13910 genotype.