David A. Peura

Control of Gastric Acid Secretion in Health and Disease

Recent milestones in the understanding of gastric acid secretion and treatment of acid-peptic disorders include the (1) discovery of histamine H(2)-receptors and development of histamine H(2)-receptor antagonists, (2) identification of H(+)K(+)-ATPase as the parietal cell proton pump and development of proton pump inhibitors, and (3) identification of Helicobacter pylori as the major cause of duodenal ulcer and development of effective eradication regimens. This review emphasizes the importance and relevance of gastric acid secretion and its regulation in health and disease. We review the physiology and pathophysiology of acid secretion as well as evidence regarding its inhibition in the management of acid-related clinical conditions.

Cimetidine for Prevention and Treatment of Gastroduodenal Mucosal Lesions in Patients in an Intensive Care Unit

The efficacy of cimetidine in the prevention and treatment of stress-induced gastroduodenal lesions was evaluated in a randomized, double-blind, placebo-controlled study in which serial endoscopy was used to examine patients without clinical evidence of bleeding who were admitted to a medical intensive care unit. Endoscopy showed that 14 of 21 patients treated with cimetidine, compared with 5 of 18 patients treated with placebo, had normal or improved gastroduodenal mucosa (p less than 0.05). Endoscopic signs of bleeding cleared or did not develop in 20 patients treated with cimetidine and in 11 patients treated with placebo (p less than 0.01). Significantly fewer blood transfusions were given to patients with endoscopic signs of bleeding in the cimetidine-treated group (0.5 +/- 0.3 [SE] units) than in placebo-treated patients (4.5 +/- 1.5 units; p less than 0.05). The mortality rate was not statistically different between treatment groups. By preventing established gastroduodenal stress lesions from progressing in severity, cimetidine diminished both bleeding and the need for transfusions.

Helicobacter pylori infection and related gastrointestinal diseases

Helicobacter pylori has been implicated in the pathogenesis of a number of digestive tract disorders, such as chronic active gastritis, peptic ulceration, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. Disease outcome is dependent on many factors, including bacterial genotype, host physiology and genetics, and environmental factors such as diet. Researchers continue to explore the complexities of H. pylori infection, seeking to explain why some individuals have asymptomatic infection, whereas others experience clinical disease. The importance of treating H. pylori infection in patients with gastrointestinal problems has been confirmed in recent years, with clinical trials showing that cure of infection can prevent duodenal ulcer and, to a lesser extent, gastric ulcer recurrence; cure early stage mucosa-associated lymphoid tissue lymphoma; and reduce the chances of developing gastric cancer in high-risk individuals.

Clinical trials: healing of erosive oesophagitis with dexlansoprazole MR, a proton pump inhibitor with a novel dual delayed-release formulation – results from two randomized controlled studies

Background  Dexlansoprazole MR employs a dual delayed‐release delivery system that extends drug exposure and prolongs pH control compared with lansoprazole.

An assessment of the management of acute bleeding varices: a multicenter prospective member-based study

OBJECTIVE:Bleeding from esophagogastric varices is a major complication of portal hypertension. Despite recent practice guidelines for the management of bleeding esophageal or gastric varices, the widespread application of these measures by gastroenterologists has not been evaluated. The purpose of this study was to continue the concept of membership-based research within diverse practice settings by expanding the American College of Gastroenterology (ACG) GI Bleeding Registry to assess the management and outcome of acute variceal bleeding.METHODS:All ACG members (domestic and foreign) were invited to participate during the 1997 Annual Fall meeting and by mail. Data were collected over 12 months. Information obtained included physician training, practice demographics, patient demographics, disease etiology and severity, clinical presentation, medications, transfusion needs, therapy, complications, and rebleeding within 2 wk.RESULTS:A total of 93 physicians/centers (79.6% domestic, 26.9% university and affiliated, 3.2% Veterans Affairs) participated. Complete demographic data were available for 725 of the 741 patients enrolled with index bleeding. The median age of these 725 patients was 52 yr and 73.3% were male. The most common single etiology for portal hypertension was cirrhosis (94.3%). The most common causes of cirrhosis were alcohol (56.7%), hepatitis C virus (30.3%), and hepatitis B virus (10.0%). Hemodynamic instability was noted in 60.7% of the patients (22.3% tachycardic, 9.7% orthostatic, 28.7% hypotensive). Index interventions included banding (40.8%; median five bands), sclerotherapy (36.3%), combination banding/sclerotherapy (6.2%), octreotide (52.6%; median 3 days), balloon tamponade (5.5%), transjugular intrahepatic portosystemic shunt (TIPS) (6.6%), liver transplantation (1.1%), surgical shunt (0.7%), and embolization (0.1%). Transfusion of packed red blood cells, fresh frozen plasma, and platelets was given in 83.4%, 44.7%, and 24.6% of the patients with index bleeding, respectively. Median transfusion was four units of packed red blood cells, three units of fresh frozen plasma, and 1.5 units of platelets. Rebleeding occurred in 92 of the 741 patients (12.6%) at a median of 7 days (mean 11 days) and was treated by banding (18.5%; median six bands), sclerotherapy (30.4%), octreotide (63%; median 2 days), balloon tamponade (17.4%), TIPS (15.2%), and surgical shunt (3.3%). Complications from the index bleeding and rebleeding within 2 wk included ulceration (2.6%, 2.2%), aspiration (2.4%, 3.3%), medication side effects (0.8%, 0%), dysphagia (2.3%, 0%), odynophagia (2.2%,0%), encephalopathy (13%,17.4%), and hepatorenal syndrome (2.4%, 2.2%), respectively. After the index bleeding, 46.2% of patients were treated with β-blockers and 8.2% with nitrates. The majority of patients with index bleeding had Childs B cirrhosis (61.5%). Patients presenting with recurrent bleeding had mostly Childs B (46.7%) or Childs C cirrhosis (44.6%). The overall short-term mortality after index bleeding was 12.9%.CONCLUSIONS:Acute variceal hemorrhage occurs more often in patients with Childs B and C cirrhosis. Endoscopic banding is the most common single endoscopic intervention. Adjunctive pharmacotherapy is prevalent acutely and after stabilization. Both morbidity and mortality may be lower than reported in previous studies.

Gastrointestinal blood loss associated with running a marathon

Gastrointestinal bleeding has been observed in long-distance runners. We prospectively studied participants of the Eighth Annual Marine Corps Marathon to determine the incidence of gastrointestinal blood loss associated with long-distance running. Of 600 runners contacted, 125 (21%) returned a questionnaire as well as pre- and postmarathon stool specimens. Stool specimens converted from Hemoccult negative to positive in 29/125 (23%) of the participants, indicating that running the marathon was associated with gastrointestinal blood loss (P<0.001). The incidence of this conversion (negative to positive) was significant for both males (N=68,P<0.001) and females (N=57,P<0.05). Gastrointestinal bleeding appeared to be independent of age, race time, abdominal symptoms, and the recent ingestion of aspirin, vitamin C, or steak.

A Novel Composite Endpoint to Evaluate the Gastrointestinal (GI) Effects of Nonsteroidal Antiinflammatory Drugs Through the Entire GI Tract

Objective. Nonsteroidal antiinflammatory drugs (NSAID) not only cause damage to the upper gastrointestinal (GI) tract but also affect the lower GI tract. To date, there is no endpoint that evaluates serious GI events in the entire GI tract. The objective of this report is to introduce a novel composite endpoint that measures damage to the entire GI tract — clinically significant upper and lower GI events (CSULGIE) — in patients with NSAID-induced GI damage. Methods. We reviewed the data from largescale, multicenter, randomized, clinical trials on lower GI toxicity associated with NSAID use. The rationale for using CSULGIE as a primary endpoint in 2 ongoing trials — the Celecoxib vs Omeprazole and Diclofenac for At-risk Osteoarthritis (OA) and Rheumatoid Arthritis (RA) Patients (CONDOR) trial and the Gastrointestinal Randomized Events and Safety Open-Label NSAID Study (GI-REASONS) — is also discussed. Results. Previous randomized trials focused primarily on damage to the upper GI tract and often neglected the lower GI tract. The CSULGIE endpoint extends the traditional “perforation, obstruction, and bleeding” assessment of upper GI complications by including events in the lower GI tract (small/large bowel) such as perforation, bleeding, and clinically significant anemia. Conclusion. By providing clinicians with a new, descriptive language for adverse events through the entire GI tract, the CSULGIE endpoint has the potential to become a standard tool for evaluating the GI effects of a range of therapies.

Meshed capillary vessels found on narrow-band imaging without optical magnification effectively identifies colorectal neoplasia: a North American validation of the Japanese experience.

BACKGROUND The presence of meshed capillary (MC) vessels is highly sensitive (96%) and specific (92%) for diagnosing colorectal neoplasia on colonoscopy by using narrow-band imaging (NBI) with optical magnification, which is not available in North America. However, the efficacy of NBI to identify an MC pattern without optical magnification has not been determined. OBJECTIVE To determine the diagnostic capabilities of NBI colonoscopy without optical magnification in differentiating neoplastic from non-neoplastic colorectal polyps by using the MC pattern. DESIGN Retrospective comparison of prospectively collected colorectal polyp data. SETTING Large, academic medical center. PATIENTS This study involved 126 consecutive colorectal polyps (median size 3 mm) that were found in 52 patients (33 men) with a median age of 59.5 years. INTERVENTION All lesions identified by white-light colonoscopy were prospectively diagnosed in real-time by using the MC pattern as determined on high-definition NBI, with 1.5x zoom but without true optical magnification, and then endoscopically excised. Surgical pathology was used as the criterion standard. MAIN OUTCOME MEASUREMENTS Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of identifying neoplastic polyps were calculated. RESULTS NBI without optical magnification was found to have a sensitivity of 93%, specificity of 88%, positive predictive value of 90%, negative predictive value of 91%, and diagnostic accuracy of 91% when all polyp sizes were considered. For lesions < or =5 mm, sensitivity was 87%, specificity was 93%, positive predictive value was 89%, negative predictive value was 91%, and diagnostic accuracy was 90%. LIMITATIONS Single-center, single-endoscopist experience. CONCLUSION Use of the MC pattern on NBI colonoscopy without optical magnification effectively distinguishes neoplastic from non-neoplastic colorectal polyps. NBI colonoscopy without optical magnification for neoplastic polyp diagnosis appears to be comparable with NBI with optical magnification when the MC pattern is used. A large, prospective trial is needed for further validation.

Small bile duct abnormalities in sarcoidosis.

We report four patients with hepatic involvement of sarcoidosis manifested primarily by bile duct depletion. The patients developed fever, weight loss, anorexia, a markedly elevated alkaline phosphatase, and mildly abnormal serum levels of aspartate aminotransferase. Endoscopic retrograde cholangiopancreatography showed slight intrahepatic irregularities but were not diagnostic of sclerosing cholangitis. Liver biopsy showed predominantly bile duct depletion, ranging from an estimated 10–100% absence of bile ducts in portal areas, which correlated with the degree of fibrosis. The degree of bile duct depletion is useful as a histological marker in patients with sarcoid liver disease. Steroids improve symptoms, but do not inhibit the development of “ductopenia.”

Running-Associated Proximal Hemorrhagic Colitis

Excerpt Gastrointestinal bleeding has been seen in long-distance runners (1), but the source of this bleeding, when not of gastric or anorectal origin, remains obscure. Intestinal ischemia has been...