Evidence-based clinical practice guidelines for gastroesophageal reflux disease 2021.

In Japan, with the increasing prevalence of gastroesophageal reflux disease (GERD) and growing public interest, the Japanese Society of Gastroenterology issued Evidence-based Clinical Practice Guidelines for GERD (1st edition) in 2009 and a revised 2nd edition in 2015. A number of studies on GERD were subsequently conducted in Japan and abroad, and vonoprazan, a potassium-competitive acid blocker (P-CAB), became available for the first time in Japan in February 2015. The revised 3rd edition (Japanese edition), which incorporates new findings and information, was published in April 2021. These guidelines are summarized herein, particularly sections related to the treatment of GERD. The important clinical issues addressed in the present revision are (i) the introduction of treatment algorithms that classify GERD into reflux esophagitis and non-erosive reflux disease, (ii) the clarification of treatment algorithms based on to the severity of reflux esophagitis, and (iii) the positioning of vonoprazan in the treatment for GERD. The present guidelines propose vonoprazan as the initial/maintenance treatment for severe reflux esophagitis. They also recommend vonoprazan or PPI as an initial treatment for mild reflux esophagitis and recommended PPI and proposed vonoprazan as maintenance treatment. These updated guidelines offer the best clinical strategies for GERD patients in Japan and hope that they will be of global use for the diagnosis and treatment for GERD.

Evidence-based clinical practice guidelines for gastroesophageal reflux disease 2015.

As an increase in gastroesophageal reflux disease (GERD) has been reported in Japan, and public interest in GERD has been increasing, the Japanese Society of Gastroenterology published the Evidence-based Clinical Practice Guidelines for GERD (1st edition) in 2009. Six years have passed since its publication, and there have been a large number of reports in Japan concerning the epidemiology, pathophysiology, treatment, and Barrett's esophagus during this period. By incorporating the contents of these reports, the guidelines were completely revised, and a new edition was published in October 2015. The revised edition consists of eight items: epidemiology, pathophysiology, diagnosis, internal treatment, surgical treatment, esophagitis after surgery of the upper gastrointestinal tract, extraesophageal symptoms, and Barrett's esophagus. This paper summarizes these guidelines, particularly the parts related to the treatment for GERD. In the present revision, aggressive proton pump inhibitor (PPI) maintenance therapy is recommended for severe erosive GERD, and on-demand therapy or continuous maintenance therapy is recommended for mild erosive GERD or PPI-responsive non-erosive GERD. Moreover, PPI-resistant GERD (insufficient symptomatic improvement and/or esophageal mucosal break persisting despite the administration of PPI at a standard dose for 8 weeks) is defined, and a standard-dose PPI twice a day, change in PPI, change in the PPI timing of dosing, addition of a prokinetic drug, addition of rikkunshito (traditional Japanese herbal medicine), and addition of histamine H2-receptor antagonist are recommended for its treatment. If no improvement is observed even after these treatments, pathophysiological evaluation with esophageal impedance-pH monitoring or esophageal manometry at an expert facility for diseases of the esophagus is recommended.

Tochu (Eucommia ulmoides) leaf extract prevents ammonia and vitamin C deficiency induced gastric mucosal injury.

The ingestion of dietary antioxidants, including vitamin C (VC), is suggested to play an important role in the prevention of gastric cancer associated with Helicobacter pylori (HP) infection. Recently, water extracts of Tochu (Du-zhong, Eucommia ulmoidea OLIVER) leaves (WETL) have been reported to have potent antioxidant and antimutagenic effects. The present study investigated the effect(s) of VC and WETL on gastric mucosal injury induced by ammonia and a VC deficient diet. Guinea pigs fed the water containing ammonia and/or a VC-deficient diet were simultaneously treated with WETL or VC. Intramucosal levels of thiobarubiturate reactive substances (TBARS), an index of lipid peroxidation, increased significantly in animals fed ammoniated water and VC-deficient diets. This was accompanied by accelerated cell proliferation and increases in immunohistochemical staining indices for oxidative stress-induced DNA adducts and strand breaks (e.g., BrdU-uptake, 8-OhdG, ssDNA and the TUNEL reaction). The administration of either WETL or VC to the ammoniated water and VC-deficient diets ameliorated the increases in intramucosal TBARS levels and labeling indices of BrdU, 8-OHdG, ssDNA and TUNEL, i.e., the levels were similar to those measured in the normal-fed control animals. These data suggest that insufficient VC ingestion may be an important risk factor for gastric cancer development in patients with HP infections. Furthermore, our results suggest that WETL or some constituent may contribute to the prevention of oxidative gastric injury that precedes carcinogenesis.