Souichi Nakagawa

The Relationship Between Consumption of Antimicrobial Agents and the Prevalence of Primary Helicobacter pylori Resistance

Background. Primary and acquired resistance to the antimicrobial agents is a primary reason for the failure of Helicobacter pylori eradication therapies. We assessed the primary antibiotic resistance rates of H. pylori to three different antibiotics and its relationship due to the annual antibiotic consumption in Japan during the period prior to approval of anti‐H. pylori therapy in Japan.

EMR combined with chemoradiotherapy: a novel treatment for superficial esophageal squamous-cell carcinoma

BACKGROUND Esophagectomy or chemoradiotherapy (CRT) are the procedures of choice for patients with superficial esophageal squamous-cell carcinoma. However, esophagectomy is highly invasive, and CRT is associated with the risk of local failure. A study was conducted of a novel treatment, EMR combined with CRT, for patients with superficial esophageal carcinoma. EMR was performed for the purpose of complete local tumor control and chemoradiotherapy was performed for regional and distant control. METHODS EMR combined with CRT was performed for patients with esophageal carcinoma invading the muscularis mucosae or upper submucosa who refused esophagectomy. The planned treatment after EMR was 40 to 46 Gy of external beam radiation to the mediastinum, including the supraclavicular fossa or cardia. Chemotherapy was given during weeks 1 and 5 (5-fluorouracil, 700 mg/m(2) per 24 hours in a 120-hour infusion, and cisplatin 15 mg/m(2) per day intravenously on days 1 to 5). RESULTS During the study period, 16 patients underwent EMR combined with CRT (EMR plus CRT group) and 39 patients with similar stage cancer underwent esophagectomy (surgical resection group). None of the patients in the EMR plus CRT group have had local recurrence or metastasis. Overall survival rates at 5 years in the EMR plus CRT and surgical resection groups were estimated to be, respectively, 100% and 87.5%. CONCLUSIONS Although this study was not randomized, the results suggest that EMR combined with CRT is a safe and effective method for treating patients with superficial esophageal carcinoma. The results were equivalent or, in view of the lower degree of invasiveness, superior to surgical resection.

Eradication of Helicobacter pylori for primary gastric cancer and secondary gastric cancer after endoscopic mucosal resection

Because most gastric cancers develop from a background of Helicobacter pylori-infected gastric mucosa, H. pylori plays an important role in gastric carcinogenesis. Therefore, eradication of H. pylori may inhibit the incidence of gastric cancers. In experimental studies, H. pylori eradication has proved to act as a prophylaxis against gastric cancer. However, the results of recent randomized controlled studies are absolutely contradictory. In Japan, mucosal gastric cancer is usually resected by endoscopic treatment. As only a small part of the gastric mucosa is resected, secondary gastric cancer after endoscopic resection of the primary gastric cancer often develops at another site in the stomach. A nonrandomized Japanese study involving 132 early gastric cancer patients reported that eradication of H. pylori after endoscopic resection tended to reduce the development of secondary gastric cancer. Also, a retrospective multicenter survey indicated that the incidence rate of secondary gastric cancer in H. pylori-eradicated patients was about one-third that among patients in the noneradication group. We conducted a large-scale multicenter randomized trial to confirm the effect of H. pylori eradication on secondary and residual gastric cancer after endoscopic resection. This study was begun in 2003 and is ongoing at present. Diagnosis of a new carcinoma at another site of the stomach is defined as the primary end point, and recurrence of tumors at the resection site as a secondary end point. A total of 542 subjects have been enrolled in the study. This study will have the statistical power to demonstrate whether H. pylori eradication decreases the incidence and recurrence of gastric cancer.

Randomized, double-blind, placebo-controlled crossover trial of famotidine in patients with functional dyspepsia.

Background : Histamine 2‐receptor antagonists were used as a first therapy against functional dyspepsia. However, few clinical studies with famotidine for functional dyspepsia have been reported.

Effects of preoperative administration of omeprazole on bleeding after endoscopic submucosal dissection: a prospective randomized controlled trial.

BACKGROUND AND AIMS The effectiveness of preoperative administration of proton pump inhibitors (PPIs) for the prevention of bleeding after endoscopic submucosal dissection (ESD) is unclear. Our aim was to evaluate the benefit of starting PPI treatment 1 day before ESD to prevent bleeding after the procedure. PATIENTS AND METHODS This was a prospective randomized controlled trial. Data for 155 patients who underwent ESD (preoperative administration group: N = 81; postoperative administration group: N = 74) were analyzed. All patients received standard ESD using an insulation-tipped knife. Patients in the preoperative group were administered omeprazole from the day before ESD, and patients in the postoperative group received omeprazole after ESD. Follow-up endoscopy was performed on day 1, day 7, and day 28. Intragastric pH was measured from samples of gastric juice. The primary endpoint of this study was major bleeding related to ESD, and the secondary endpoint was minor bleeding. RESULTS Major bleeding occurred in one patient from the postoperative group who had hematemesis. Minor bleeding occurred on day 1 in six patients from the preoperative group and five patients from the postoperative group (7.7 % vs. 7.4 %). There was no significant difference between major and minor bleeding ratios in the two groups. Intragastric pH at ESD in the postoperative group was lower than that in the preoperative group ( P < 0.05). CONCLUSIONS Preoperative administration of omeprazole offers no additional benefit over postoperative administration alone in the prevention of bleeding after ESD among elderly Japanese people.

Preliminary Trial of Rebamipide for Prevention of Low-Dose Aspirin-Induced Gastric Injury in Healthy Subjects: A Randomized, Double-Blind, Placebo-Controlled, Cross-Over Study

Although low-dose aspirin is widely used, since it is a cheap and effective means of prevention of cardiovascular events, it can cause hemorrhagic gastrointestinal complications. The aim of this study was to evaluate the efficacy of rebamipide in preventing low-dose aspirin-induced gastric injury. A randomized, double-blind, placebo-controlled, crossover trial was performed in twenty healthy volunteers. Aspirin 81 mg was administered with placebo or rebamipide 300 mg three times daily for 7 consecutive days. The rebamipide group exhibited significant prevention of erythema in the antrum compared with the placebo group (p = 0.0393, respectively). Results for the body and fornix did not differ significantly between the placebo and rebamipide groups. In conclusion, short-term administration of low-dose aspirin induced slight gastric mucosal injury in the antrum, but not in the body or fornix. Rebamipide may be useful for preventing low-dose aspirin-induced gastric mucosal injury, especially which confined to the antrum.

USEFULNESS OF MAGNIFYING ENDOSCOPY IN UPPER GASTROINTESTINAL TRACT: HISTORY AND RECENT STUDIES

Although clinical trials using magnifying optical endoscopy have been reported, magnifying endoscopies have been remarkably developed in the period of electronic endoscopy. Magnifying electronic endoscopies with 80 or 100‐fold magnification are used for routine endoscopic examination of upper gastrointestinal tract in Japan. Magnifying endoscopy is used to visualize the microstructure and microvascular architecture of gastrointestinal surface mucosa. Microsurface structure of the mucosa includes normal structure, changed structure by inflammation and biological response, and tumor‐specific structure. Microvascular architecture includes normal vascular system and tumor microvessels. Magnifying endoscopy is starting to play an important role in diagnosis of any upper gastrointestinal diseases by assessment of magnified observation. Magnifying endoscopy holds a great deal of promise in the near future because magnifying endoscopic observation is approaching optical biopsy.

THE RESULTS OF QUESTIONNAIRE ABOUT ENDOSCOPIC MUCOSAL RESECTION IN THE STOMACH

Isolated exfoliation method of gastric endoscopic mucosal resection (EMR) as a new technique has not yet reached the popularity of the conventional EMR techniques. From the results of a questionnaire about EMR in the stomach, the isolated exfoliation method has the advantage of permitting en bloc and histologically complete resection regardless of lesion size. However, this method has the disadvantage of long performance time and high frequency of complication as well as the need for a high level of technical skill. New devices and ideas are needed for the development of the isolated exfoliation method.

A Case Report of the Therapeutic Effect of Cryofiltration in a Patient With Glucocorticoid‐Resistant Ulcerative Colitis

Abstract:  Ulcerative colitis (UC) is characterized by chronic inflammation of the colon and its cause and pathogenesis have not been fully clarified. Although UC is treated with various drugs, including 5‐amino‐salycilate and glucocorticoids, some patients are resistant to them. It was recently reported that apheresis, such as leukocytapheresis and granulocytapheresis, improves intestinal inflammation in refractory cases of UC. On the other hand, cryofiltration, in which plasma apheresis is used to remove immunoglobulin and immune complexes, has been used for the treatment of autoimmune diseases. We herein report a case of glucocorticoid‐resistant UC successfully treated with cryofiltration. Interestingly, the level of interleukin‐10 (IL‐10) in the patients serum was markedly increased after eight sessions of cryofiltration. This suggests that cryofiltration suppresses intestinal inflammation, in part via up‐regulation of IL‐10.

THE EFFICACY OF MAGNIFYING ENDOSCOPY WITH ADAPTIVE INDEX OF HEMOGLOBIN ENHANCEMENT FOR DIAGNOSIS OF HELICOBACTER PYLORI-INDUCED GASTRITIS

Two decades have passed since Helicobacter pylori ( H. pylori ) was first confirmed to be present on the gastric mucosal surface. Many basic and clinical studies have been carried out to investigate the relationship between H. pylori and gastrointestinal disorders. Helicobacter pylori is now established as a major cause of histological gastritis, gastric ulcer, duodenal ulcer, gastric carcinoma, and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Eradication of H. pylori is extremely effective in improving histological gastritis, preventing recurrence of peptic ulcers, promoting rapid healing of peptic ulcers, and inducing complete remission of gastric low-grade MALT lymphoma. Although biopsied specimens obtained during endoscopic performance are often used for the detection of H. pylori infection, it would be of great value to be able to diagnose the presence of H. pylori infection by specific endoscopic findings without biopsy. Atrophic features observed using endoscopy could suggest H. pylori -induced chronic gastritis. However, endoscopic features that are associated with histopathological findings of inflammation and activity are usually non-specific. At the present, no consensus has been reached about whether or not gastritis related to H. pylori can be diagnosed from microscopic changes of the gastric mucosa.