Gastroesophageal Reflux Disease: Pathophysiology and New Treatment Trends.

Gastroesophageal reflux disease (GERD) is caused by the reflux of gastric contents into the esophagus due to a decline in esophageal clearance and anti-reflux barrier mechanisms. Mucosal injury is caused by a combination of gastric juice directly damaging the esophageal mucosa and the immune and inflammatory mechanism in which inflammatory cytokines released from the esophageal mucosal epithelium cause neutrophil migration, triggering inflammation. Gastric secretion inhibitors are the first-line treatment for GERD, but they can be combined with prokinetic agents and Chinese herbal remedies. However, pharmacotherapy cannot improve anatomical problems or prevent physical causes of GERD, such as reflux of non-acidic contents. Therefore, surgery can be warranted, depending on the pathology. Intraluminal endoscopic therapy, which is both less invasive and more effective than surgery, was recently developed and applied in Europe and the United States. In Japan, intraluminal endoscopic therapies, such as anti-reflux mucosectomy, anti-reflux mucosal ablation, and endoscopic submucosal dissection, for GERD have been independently developed.

Evidence-based clinical practice guidelines for functional dyspepsia 2021.

BACKGROUND: Functional dyspepsia (FD) is a disorder that presents with chronic dyspepsia, which is not only very common but also highly affects quality of life of the patients. In Japan, FD became a disease name for national insurance in 2013, and has been gradually recognized, though still not satisfactory. Following the revision policy of Japanese Society of Gastroenterology (JSGE), the first version of FD guideline was revised this time. METHOD: Like previously, the guideline was created by the GRADE (grading of recommendations assessment, development and evaluation) system, but this time, the questions were classified to background questions (BQs, 24 already clarified issues), future research questions (FRQs, 9 issues cannot be addressed with insufficient evidence), and 7 clinical questions that are mainly associated with treatment. RESULTS AND CONCLUSION: These revised guidelines have two major features. The first is the new position of endoscopy in the flow of FD diagnosis. While endoscopy was required to all cases for diagnosis of FD, the revised guidelines specify the necessity of endoscopy only in cases where organic disease is suspected. The second feature is that the drug treatment options have been changed to reflect the latest evidence. The first-line treatment includes gastric acid-secretion inhibitors, acetylcholinesterase (AChE) inhibitors (acotiamide, a prokinetic agent), and Japanese herbal medicine (rikkunshito). The second-line treatment includes anxiolytics /antidepressant, prokinetics other than acotiamide (dopamine receptor antagonists, 5-HT4 receptor agonists), and Japanese herbal medicines other than rikkunshito. The patients not responding to these treatment regimens are regarded as refractory FD.

Vonoprazan-Based Triple-Therapy Could Improve Efficacy of the Tailored Therapy of Helicobacter pylori Infection.

BACKGROUND AND AIMS: The prevalence of clarithromycin resistant bacteria is increasing, and the effectiveness of Helicobacter pylori (H. pylori) triple therapy is gradually decreasing in Japan. Vonoprazan, a potassiumcompetitive acid blocker, has been reported for its effectiveness in eradicating H. pylori. We aimed to evaluate the efficacy of tailored vonoprazan-based triple therapy in patients with H. pylori. This study is the first to compare the efficacy of vonoprazan-based tailored triple therapy to that of vonoprazan-based conventional therapy. METHOD: This retrospective cohort study evaluated the treatment efficacy in 920 patients. Of these, 541 received conventional and 379 received tailored therapy. Successful eradication was confirmed by a negative 13C-urea breath test 6-8 weeks following completion of H. pylori eradication therapy, and the data were evaluated using the Chi-square test, or Fisher's exact test, as appropriate. RESULTS: The eradication rate of tailored therapy was 90% and 96.3% by intent-to-treat analysis and per protocol analysis, respectively, which was significantly higher than the 85% and 90.2% found for conventional therapy (p < 0.05 and p < 0.001, respectively). Amoxicillin- or clarithromycin-resistant bacteria did not affect treatment outcomes. By univariate and multivariate analysis, both amoxicillin- and clarithromycin-resistant bacteria and conventional therapy were detected as risk factors for eradication failure (odds ratio = 6.267, 95% CI [1.056-119.924], p < 0.05, and odd ratio =3.113, 95% confidence interval [1.688-6.160], p < 0.001, by multivariate analysis). CONCLUSION: Vonoprazan-based triple therapy could be a more effective treatment for H. pylori infection than conventional therapy when combined with a therapy regimen tailored according to bacterial antibiotic susceptibility.

Association of baseline plasma des-acyl ghrelin level with the response to rikkunshito in patients with functional dyspepsia.

BACKGROUND AND AIM: We recently conducted a randomized placebo-controlled trial on the efficacy and safety of rikkunshito, a standardized Japanese herbal medicine, for the treatment of functional dyspepsia (FD). The present post-hoc study aimed to evaluate the differences in clinical characteristics between responders and non-responders among FD patients who received rikkunshito for 8 weeks. METHODS: Rikkunshito responders were defined by using a global patient assessment. Candidate predictors included age, gender, smoking, alcohol consumption, body mass index, comorbidity, Helicobacter pylori infection, plasma levels of acyl ghrelin and des-acyl ghrelin, severity of dyspeptic symptoms, FD subgroup, previous medication, and the type of recruiting institution (clinic or hospital). We calculated hazard ratios (HRs) by using Cox regression analysis with the factors that were indicated to be associated with responders. RESULTS: We assigned 83 and 42 patients to responder and non-responder categories, respectively. Lack of alcohol consumption (HR, 2.04; 95% confidence interval, 1.08-3.88) and low plasma des-acyl ghrelin levels (< 177 fmol/mL; HR, 2.42; 95% confidence interval, 1.24-4.73) were significantly associated with the efficacy of rikkunshito. Lack of alcohol consumption was associated with the efficacy of rikkunshito especially among H. pylori-infected participants. On the other hand, the low plasma des-acyl ghrelin was associated with the efficacy of rikkunshito especially among H. pylori-negative participants. CONCLUSIONS: A low baseline level of plasma des-acyl ghrelin was associated with an increased treatment efficacy of rikkunshito against FD. Lack of alcohol consumption was also clinically useful for predicting the response to rikkunshito.

Solitary amyloidosis of the sigmoid colon featuring submucosal tumor caused hematochezia.

A previously a healthy 64-year-old woman complained of a two-week history of hemorrhaging upon defecation. The laboratory and urinalysis findings were normal, and no serum or urine M components were detectable on protein electrophoresis. An air contrast barium enema revealed an elevated lesion measuring -20 mm in diameter with a smooth surface and a depression in the sigmoid colon. Colonoscopy revealed a red colored and congested tumor. The exposed surface of the submucosal tumor (SMT) center was somewhat yellow in color and covered with fuzz. All other portions of the colon were normal. The endoscopy and double-contrast barium revealed a normal upper gastrointestinal tract and a normal small intestine, respectively. A histopathological evaluation of a biopsy specimen obtained from the SMT suggested amyloid deposition. However, the other biopsy specimens of the esophagus, stomach, duodenal bulb, second portion of the duodenum, terminal ileum and other portions of the colon demonstrated no amyloid deposition. Colonoscopic ultrasonography (US) revealed the hypoechoic, homogeneous SMT to be mainly localized within the submucosa. An endoscopic submucosal resection (EMR) of the solitary amyloidosis was performed and the immunohistopathology revealed the entire SMT to consist of amyloid light chain kappa amyloid deposition. We considered that the US followed by EMR contributed to the precise diagnosis of solitary amyloidosis and the treatment of hematochezia caused by a solitary area of amyloidosis within the sigmoid colon.

Intussusception in a child caused by capillary hemangioma of the colon.

Intussusception is one of the most common abdominal emergencies in children, but identifying the cause is very difficult. Hemangioma is a common tumor of the head and neck area in children, but it rarely arises in the gastrointestinal tract. This report describes a rare occurrence of intussusception caused by capillary hemangioma of the colon that was identified by ultrasonography (US), computed tomography (CT), and colonoscopy. A male child aged 2 years and 10 months developed painful abdominal cramps and hematochezia. Abdominal US and CT revealed both target and pseudo-kidney signs in the colon, indicating colonic intussusception. An initial diagnostic and therapeutic laparotomy did not reveal any abnormalities. Seven days later, severe abdominal pain recurred. A barium enema revealed the shadow of a 25-mm mass at the hepatic flexure of the colon. Colonoscopic findings revealed a submucosal tumor in the descending colon that was moved to the cecum by compressed air introduced through the colonoscope. We considered that the mass in the cecum had caused the intussusception. The tumor was removed at a second laparotomy, and microscopic pathological examination revealed that it was a capillary hemangioma.

Association of polymorphism in the human mu-opioid receptor OPRM1 gene with proinflammatory cytokine levels and health perception.

Recent studies in psychoneuroimmunology have indicated that proinflammatory cytokines cause several diseases and behaviors that overlap symptomatically with depression. It is known that the endogenous opioid peptide beta-endorphin regulates proinflammatory cytokine secretion from peripheral immune cells via mu-opioid receptor-dependent mechanisms. Therefore, it is possible that the functional polymorphism of the mu-opioid receptor gene (OPRM1, SNP: A118G) influences peripheral circulating proinflammatory cytokine levels and the health-related quality of life (QOL) even in healthy populations. In this study, we compared the serum concentrations of several proinflammatory cytokines (interleukin-2 (IL-2), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma)) and the health-related QOL between OPRM1 genotypes. Interestingly, serum concentrations of IL-6, TNF-alpha, and IFN-gamma were significantly lower and the general health score was significantly higher in carriers of the G allele, who show a strong binding of beta-endorphin to the mu-opioid receptor as compared to individuals without the G allele. Correlation analysis indicated that the general health score was negatively correlated with the IL-6 serum concentration. These results suggest that the sensitive endogenous opioid system in carriers of the G allele may suppress proinflammatory cytokine secretion from peripheral immune cells; consequently, it may influence the health perception.

Successful treatment for pouchitis with rebamipide refractory to a combination of metronidazole (MNZ) and ciprofloxacin (CFX).

A 35-year-old male who had undergone proctocolectomy and ileo-anal pouch surgery (IPAA) because of ulcerative colitis presented with worsening diarrhea and hematochezia. Pouchitis was diagnosed, and he was prescribed with metronidazole (MNZ) and a betamethasone enema. However, his condition did not remarkably improve despite these strategies. Endoscopy revealed ulceration and inflammation in the ileal pouch together with contact bleeding and mucous discharge. He underwent granulocytapheresis (G-CAP) and was prescribed anal 5-aminosalicylic acid (5-ASA) and oral prednisolone. Oral azathioprine (AZA) and a combination of MNZ and ciprofloxacin (CFX) did not result in any improvement. He was then treated with rebamipide enemas twice daily for 8 weeks without additional drug therapy. Two weeks thereafter, stool frequency started to decrease, fecal hemoglobin became negative, and his symptoms gradually improved. Endoscopic findings after the rebamipide therapy showed that the ulcers in the ileal pouch had mostly healed without obvious inflammation and bleeding. Rebamipide was thus maintained throughout the therapeutic period and for 13 months of follow-up. Rebamipide effectively treated severe pouchitis that was refractory to intensive conventional medication including antibiotics and corticosteroids.

Rebamipide enemas-new effective treatment for patients with corticosteroid dependent or resistant ulcerative colitis.

In this study we investigated the effect of rebamipide enema in patients with steroid-resistant and/or dependent ulcerative colitis. Rebamipide enemas were administered twice daily for a 12-week period; this treatment was further continued longer in patients who requested this. Disease activity index as reflecting the clinical condition and endoscopic index with histological grading were determined before and after the treatment period. Nine of 11 (81.8%) patients on 12-week treatment with rebamipide approved and were classified as colitis in remission. Moreover, seven of 11 patients requested long-term medication, the longest medication term being 80 weeks. These results medicated that rebamipide enemas may be effective in patients with steroid-resistant and/or dependent ulcerative colitis.