Evolution of gastro-oesophageal reflux disease over 5 years under routine medical care--the ProGERD study

BACKGROUND

The evolution of gastro-oesophageal reflux disease (GERD) under current management options remains uncertain.

AIM

To examine whether, depending on the initial presentation, non-erosive (NERD) and erosive reflux disease (ERD) without Barrett's oesophagus will progress to more severe disease under current routine care following the resolution of the initial condition.

METHODS

Patients with the primary symptom of heartburn were included at baseline, and stratified into non-erosive (NERD) and erosive reflux disease (ERD), LA grades A-D (Los Angeles classification). After a 2- to 8-week course with esomeprazole therapy to achieve endoscopic healing in ERD and symptom relief in NERD, patients were treated routinely at the discretion of their physician. We report oesophagitis status and the presence of endoscopic and confirmed Barrett's oesophagus after 5 years.

RESULTS

A total of 6215 patients were enrolled in the study of whom 2721 patients completed the 5-year follow-up. Progression, regression and stability of GERD severity were followed from baseline to 5 years. Only a few patients with NERD and mild/moderate ERD progressed to severe forms of ERD and even Barrett's oesophagus. Most patients remained stable or showed improvement in their oesophagitis; 5.9% of the NERD patients, 12.1% of LA grade A/B patients and 19.7% of LA grade C/D patients in whom no Barrett's oesophagus was recorded at baseline progressed to endoscopic or confirmed Barrett's oesophagus at 5 years.

CONCLUSION

Most GERD patients remain stable or improve over a 5-year observation period under current routine clinical care.

A summary of Food and Drug Administration-reported adverse events and drug interactions occurring during therapy with omeprazole, lansoprazole and pantoprazole

BACKGROUND

Pantoprazole is claimed to have a lower potential for drug interaction than other proton pump inhibitors.

AIM

To estimate the frequency of adverse events and drug interactions reported to the Food and Drug Administration in patients receiving omeprazole, lansoprazole or pantoprazole.

METHODS

The study involved a search of the Food and Drug Administration's database for adverse events and drug interactions with omeprazole, lansoprazole or pantoprazole as primary or secondary suspect drug. An estimate of the amount of drug dispensed during the adverse event collection period (from US drug launch) was obtained from the International Medical Statistics health database.

RESULTS

Of the suspected drug interactions recorded, vitamin K antagonist interactions, although rare, were the most common. The frequency of vitamin K antagonist interactions was 0.09 per million packages for omeprazole and 0.11 per million packages for lansoprazole and pantoprazole. Interactions with benzodiazepines or phenytoin were even rarer, being reported in less than 10 patients on each proton pump inhibitor.

CONCLUSION

The frequency of reported drug interactions was low for omeprazole, lansoprazole and pantoprazole and vitamin K antagonist interactions were by far the most common. These potentially important drug interactions, although rare, were no less frequent on pantoprazole than on omeprazole or lansoprazole, suggesting a class effect.

Treatment of Helicobacter pylori in functional dyspepsia resistant to conventional management: a double blind randomised trial with a six month follow up

BACKGROUND

Previous studies on the treatment of Helicobacter pylori infection in functional dyspepsia have shown little, if any, effect on dyspeptic symptoms. However, whether such treatment might be of benefit in patients resistant to acid inhibitors has not been formally tested.

AIM

The present study investigated the effect of H pylori treatment in patients with functional dyspepsia resistant to conventional treatment.

PATIENTS

A total of 181 H pylori positive patients with chronic functional dyspepsia who had not responded to a one week antacid run-in and two week double blind antisecretory or placebo treatment were included.

METHODS

Patients were randomised to two weeks of treatment with omeprazole 40 mg twice daily combined with amoxicillin 1 g twice daily or omeprazole 20 mg once daily alone. The primary outcome variable ("response") was defined as no need for further therapy or investigations for dyspeptic symptoms 4-6 months after treatment.

RESULTS

H pylori infection was healed in 10% of patients after omeprazole and in 52% after omeprazole plus amoxicillin. The respective "response" rates were 66% and 62% (NS). H pylori treatment and cure of H pylori infection had no effect on complete resolution of all dyspeptic symptoms, individual symptoms, or various aspects of quality of life.

CONCLUSION

In functional dyspepsia, H pylori treatment and cure of H pylori are no more effective for symptoms over six months than short term acid inhibition. These results do not support treatment of H pylori in functional dyspepsia.

Primary prevention of diclofenac associated ulcers and dyspepsia by omeprazole or triple therapy in Helicobacter pylori positive patients: a randomised, double blind, placebo controlled, clinical trial

BACKGROUND

There is much controversy as to whether or not treatment of Helicobacter pylori reduces the occurrence of peptic ulcers during therapy with a non-steroidal anti-inflammatory drug (NSAID).

AIM

To assess the efficacy of triple therapy or omeprazole on the occurrence of diclofenac associated ulcers in H pylori positive patients.

METHODS

This was a randomised, double blind, placebo controlled, multicentre trial in H pylori positive patients requiring NSAID therapy who had no past or current peptic ulcer. They received diclofenac 50 mg twice daily for five weeks in combination with one of the four randomly assigned treatments: anti-H pylori treatment for one week (omeprazole 20 mg+clarithromycin 500 mg+amoxicillin 1 g, all twice daily) followed by placebo for four weeks (OAC-P); anti-H pylori treatment for one week followed by antisecretory treatment with omeprazole 20 mg once daily for four weeks (OAC-O); omeprazole 20 mg once daily for five weeks (O-O); or placebo for five weeks (P-P). Patients were endoscoped before and after treatment.

RESULTS

Data from 660 patients were included in an intention to treat analysis. The occurrence of peptic ulcers in the four treatment groups during the study period was: 1.2% for OAC-P, 1.2% for OAC-O, 0% for O-O, and 5.8% for P-P (p<0.05 between placebo and all active treatment groups). Patients who received active treatment developed therapy requiring dyspeptic symptoms less frequently than those who received placebo (p<0.05 between placebo and all active treatment groups).

CONCLUSIONS

In H pylori infected patients, all three active therapies reduced the occurrence of NSAID associated peptic ulcer and dyspeptic symptoms requiring therapy.

Short course acid suppressive treatment for patients with functional dyspepsia: results depend on Helicobacter pylori status. The Frosch Study Group

BACKGROUND AND AIMS

Treatment of functional dyspepsia with acid inhibitors is controversial and it is not known if the presence of Helicobacter pylori infection influences the response.

METHODS

After a complete diagnostic workup, 792 patients with functional dyspepsia unresponsive to one week of low dose antacid treatment were randomised to two weeks of treatment with placebo, ranitidine 150 mg, omeprazole 10 mg, or omeprazole 20 mg daily. Individual dyspeptic and other abdominal symptoms were evaluated before and after treatment according to H pylori status.

RESULTS

The proportions of patients considered to be in remission (intention to treat) at the end of treatment with placebo, ranitidine 150 mg, omeprazole 10 mg, and omeprazole 20 mg were, respectively, 42%, 50%, 48%, and 59% in the H pylori positive group and 66%, 73%, 64%, and 71% in the H pylori negative group. In H pylori positive patients, the therapeutic gain over placebo was significant for omeprazole 20 mg (17.6%, 95% confidence intervals (CI) 4.2-31.0; p<0.014 using the Bonferroni-adjusted p level of 0.017) but not for omeprazole 10 mg (6.8%, 95% CI -6.7-20.4) or ranitidine 150 mg (8.9%, 95% CI -4.2-21. 9). There was no significant therapeutic gain from active treatment over placebo in H pylori negative patients. Complete disappearance of symptoms and improvement in quality of life also occurred most frequently with omeprazole 20 mg and was significant in both H pylori positive and H pylori negative groups. The six month relapse rate of symptoms requiring treatment was low (<20%) in all groups.

CONCLUSIONS

Omeprazole 20 mg per day had a small but significant favourable effect on outcome in H pylori positive patients. The differential response in these patients may be explained by an enhanced antisecretory response in the presence of H pylori. The effect of weaker acid inhibition was unsatisfactory.

Helicobacter pylori and functional dyspepsia: a real causal link?

This chapter reviews the evidence for a link between functional dyspepsia and Helicobacter pylori infection from three angles. In the section on pathophysiology, we evaluate how H. pylori could theoretically produce dyspeptic symptoms: many mechanisms can be proposed. In the discussion on epidemiology, we evaluate possible associations between the occurrence of symptoms and infection. Here, many studies claiming a coincidence or chronological sequence of infection and symptoms are criticized because of their poor design. In the section on the improvement of functional dyspepsia by the treatment of H. pylori infection, the conclusion is reached that if such an effect occurs at all--which is unlikely--it is very weak. The controversy on the link between H. pylori infection and functional dyspepsia is presently ongoing. Some authors are still trying to save an elegant concept that once looked so plausible but now has the facts against it.

[Gastroenterology. II: Acid research and ulcer therapy]

Three discoveries of the last thirty years have revolutionized acid research and ulcer therapy: H2-receptors and their competitive inhibition, the acid pump and its blockade and, finally, Helicobacter pylori and its central role in ulcer disease. Today the problem of ulcer treatment is more or less solved by the correct use of antibiotics, while the cure of reflux disease is still problematic: pump blockers accelerate the healing of mucosal breaks and prevent, when given at long term, recurrences but they cannot change the natural history of reflux disease. These facts form the basis for future research.

[Reflux, lung and heart]

The connections between gastroesophageal reflux, nonallergic asthma and angina pectoris are critically reviewed. Although there is no convincing evidence of a widespread pathophysiological link, such interaction may play a role in selected cases.

Comparison between esophageal Wallstent and Ultraflex stents in the treatment of malignant stenoses of the esophagus and cardia

BACKGROUND AND STUDY AIMS

Several published studies have examined various self-expanding metal esophageal stents for use in the palliative treatment of esophageal or cardiac neoplasia, but few have compared different self-expanding metal stents. The aim of this study was to evaluate non-covered Wallstent and Ultraflex prostheses in the treatment of malignancies in the esophagus and the cardiac region.

MATERIALS AND METHODS

In a retrospective study, the effectiveness of non-covered Wallstents (46 patients) and Ultraflex stents (36 patients) was compared in the treatment of malignancies in the esophageal and cardiac regions.

RESULTS

Reintervention procedures were necessary in 16 of the 46 Wallstent patients (six patients during an early phase) and in 22 of the 36 Ultraflex patients (13 during an early phase) (overall P = 0.022; early P = 0.018). The major complication in the Wallstent group was tumor ingrowth (12 of 35 complications), while in the Ultraflex group, it was incomplete deployment (18 of 49 complications). Incomplete stent deployment occurred more often in patients treated with Ultraflex (P = 0.01), and food impaction was more often observed in the Wallstent group (P = 0.001). In addition, in patients with Ultraflex stents, more complex reinterventions were necessary than those required with Wallstents (four vs. 13 complex reinterventions, P = 0.0046). Wallstents tended to improve dysphagia better than Ultraflex stents.

CONCLUSION

Compared to Ultraflex stents, Wallstents have several significant short-term and long-term advantages in the palliative treatment of malignancy of the esophagus and cardia.

[Recurrence of reflux esophagitis can be prevented with maintenance therapy with sucralfate]

OBJECTIVE

To determine whether the recurrence of reflux oesophagitis can be prevented with sucralfate suspension 2 g daily.

DESIGN

Double-blind, placebo-controlled, multinational drug study.

SETTING

Sixteen research centres in Switzerland, Germany and the Netherlands.

METHOD

184 Patients whose earlier reflux oesophagitis Savary-Miller grades I and II were cured by an antisecretory therapy before being included in the study. For 6 months, they were given 2 g of a sucralfate suspension or a placebo twice daily, with random division. The symptoms were checked monthly. Endoscopy was performed at the end of the study or when there was a clinical suspicion of recurrence.

RESULTS

Eighty-eight patients of the sucralfate group and 93 of the placebo group could be evaluated. The proportion of endoscopical recurrence was significantly reduced (31 in the sucralfate group as against 55 in the placebo group; p < 0.001). This decrease was particularly clear where symptomatic recurrences were concerned (10 and 34%, respectively; p < 0.001).

CONCLUSION

This is the first trial that demonstrates that sucralfate suspension can prevent recurrences of reflux oesophagitis in patients with solitary or confluent erosions previously cured with an antisecretory therapy.

Sucralfate maintenance therapy in reflux esophagitis. Sucralfate Investigational Working Team

OBJECTIVE

to prove in a double-blind placebo-controlled multinational trial the effects of sucralfate suspension 2 g BID and placebo in the prevention of recurrent reflux esophagitis.

METHODS

One hundred and eighty-four patients from 16 centers with reflux esophagitis Savary grade 1 and 2 were initially healed with antisecretory therapy before entering the study. They were randomly allocated to sucralfate suspension 2 g BID or placebo for 6 months. Symptoms were monitored monthly. Endoscopy was performed at the end of the trial or earlier in case of clinical suspension of relapse.

RESULTS

The two treatment groups were well matched. We were able to analyze 88 sucralfate- and 93 placebo-treated patients. There was a significant reduction in the endoscopic relapse rate (31% in the sucralfate group vs. 65% in the placebo group, p < 0.001). This reduction was especially obvious for symptomatic relapses (10% vs. 34%, respectively, p < 0.001).

CONCLUSION

This is the first study to show that sucralfate suspension is capable of preventing recurrent reflux esophagitis in patients with solitary or confluent erosions previously healed with antisecretory therapy.

[Dyspepsia: work-up or provisional treatment?]

Dyspepsia is defined as symptoms that are considered by a physician to originate from the upper gastrointestinal tract. The term 'functional dyspepsia' designates dyspepsia after exclusion of organic causes. Dyspepsia is a frequent problem in general practice. Mainly for economical reasons, it is impossible to perform every available diagnostic test in every patient to exclude all possible organic causes. The initial work-up is directed at identifying alarm symptoms and alarm signs from history, physical examination, and simple laboratory tests. The presence of any alarm symptoms or alarm sign requires prompt investigation. If none can be found, empirical drug treatment may be performed according to the leading symptom. Treatment failure or rapid recurrence require additional investigations, in particular by gastroscopy.

[Ulcer prevention during anti-rheumatism therapy and in intensive medicine]

Gastrointestinal side effects are common to all nonsteroidal anti-inflammatory drugs (NSAID). Relevant to the patient are NSAID-induced dyspepsia and ulcer complications such as hemorrhage and perforation. The most important prophylactic means is repeated verification that the NSAID cannot be replaced by other measures, e.g. physical therapy or simple analgesics. If a NSAID is needed, it should be administered at the lowest effective dose. The present drugs used in preventing NSAID-induced ulcers and their complications are far from perfect. Major problems are adverse effects, high costs and insufficient efficacy in the prevention of ulcer complications. Thus, prophylactic antiulcer treatment is recommended in high-risk patients (as a primary prophylaxis) and in patients with previous ulcers (as a secondary prophylaxis). Similar arguments apply for prevention of ulcers in intensive-care patients. Patients at risk are critically ill, those with previous ulcers and in particular those with clotting disorders. Acid-reducing drugs are recommended for nonintubated patients, whereas sucralfate is preferred in patients on artificial ventilation because it is associated with a lower risk for nosocomial pneumonias.

[Therapy of gastroesophageal reflux disease]

The natural history of gastroesophageal reflux disease is usually that of a chronic disorder. Spontaneous remission is rare, and cure even more so, especially in more severe cases. Treatment of esophagitis has been eased in most cases with current drugs, but recurrence is almost the rule after discontinuation of therapy. Therefore, long-term treatment is required in many patients. The drugs of preference for long-term treatment are acid inhibitors given at the lowest dose that suppresses symptoms. Surgical treatment should be reserved for the rare patient who cannot be managed satisfactorily with conservative treatment. Because of the high risk of adenocarcinoma in Barret's esophagus, endoscopic surveillance of all patients with acceptable surgical risk is recommended.

Comparison of pantoprazole and ranitidine in the treatment of acute duodenal ulcer. Pantoprazole-Duodenal Ulcer-Study Group

BACKGROUND

Pantoprazole is a new substituted benzimidazole that blocks the H+/K(+)-ATPase in the gastric mucosa and thus inhibits acid secretion.

METHODS

Efficacy and tolerability of pantoprazole (40 mg at breakfast) and ranitidine (300 mg at bedtime) in the treatment of uncomplicated acute duodenal ulcer were compared in a double-blind randomized multicentre trial.

RESULTS

Of 202 outpatients who entered the study, 185 terminated the treatment without violation of the protocol. After 2 weeks of treatment, healing rates (protocol correct) with pantoprazole and ranitidine were 81 and 53%, respectively (P < 0.001), the corresponding results after 4 weeks were 97 and 83% (P < 0.01). Pantoprazole was more effective with respect to symptom relief. Both treatments were well tolerated.

CONCLUSION

Pantoprazole 40 mg at breakfast is superior to ranitidine 300 mg at bedtime in the short-term treatment of acute, uncomplicated duodenal ulcer.

[Prevention of recurrence of ulcer disease: indications and choice of procedure]

In this contribution we discuss the relapse prophylaxis of ulcers by nonmedicamentous measures, by long-term drug therapy and, in particular, with inhibitors of secretion, by eradication therapy of Helicobacter pylori and by surgical therapy. Besides secondary prophylaxis (prevention of ulcer relapses), primary prophylaxis (prevention of the first episode) is also briefly treated.

[Therapy of the acute ulcer attack]

Medical treatment of acute ulcers can be optimized by paying attention to risk factors for slow healing and for rapid recurrence. Therapy-resistant ulcers have become virtually unknown with modern drugs, so elective ulcer surgery is nowadays rarely needed for this reason. While drug therapy of acute ulcer hemorrhage is probably of little, if any, benefit for stopping bleeding, endoscopic treatment reduces the risk of continuous or recurrent bleeding, the need for emergency surgery, and mortality of this most common complication.

[Intramural rupture and intramural hematoma of the esophagus: 3 case reports and literature review]

Together with three of our own observations of intramural rupture (IRO) or hematoma (IHO) of the esophagus, we have analyzed 91 case reports from the literature. Precipitating factors were identified in 63% of all patients. Most frequently potentially traumatic events such as vomiting (22%) or instrumentation (17%) preceded IRO/IHO. In 21% there were disturbances of hemostasis, either alone (15%) or in addition to a traumatic event (6%). 37% of IRO/IHO were spontaneous. In 35% the typical clinical triad of acute retrosternal pain, odynophagia or dysphagia and hematemesis was complete; in 46% only two out of three symptoms were present. IRO/IHO was managed conservatively in 84% of the patients, whereas 9% required surgery for complications. 7% were operated on without a precise indication. One patient died following surgery for endoscopic perforation. The rare syndrome of IRO/IHO must be considered in patients with acute retrosternal pain. Treatment is primarily conservative and the prognosis is excellent.

Gastric acid in vertebrates

Gastric secretion of hydrochloric acid appears to be unique to vertebrates and is almost ubiquitous in all fishes, amphibians, reptiles, birds and mammals. Comparative anatomy and physiology suggest that gastric acid has evolved approximately 350 million years ago. The similarity of the acid-secreting mechanism across all classes of vertebrates implies a major advantage for selection, but the evidence regarding its precise purpose remains inconclusive.

Smoking and pH response to H2-receptor antagonists

Smoking has been shown to impair the therapeutic effect of H2-receptor antagonists. To evaluate the acid-reducing capacity of H2-receptor antagonists in relation to smoking habits, we tested the effect of ranitidine (Ran) and famotidine (Fam) under physiologic conditions, using ambulatory pH-metry. Intragastric pH was measured over 20 h. Each of 18 healthy volunteers, 9 smokers and 9 nonsmokers, received 40 mg Fam, 300 mg Ran, or placebo in a double-blind, randomized study as a single evening dose. With both drugs 20-h acidity was markedly suppressed. After Fam treatment mean inhibition was 61% in smokers and 76% in nonsmokers and after Ran 51% and 67%, respectively. When areas under the pH curves for each individual were calculated and treatment compared with placebo (= 100%), the response was smaller in smokers than in nonsmokers with either drug (Fam, 153 +/- 21% versus 214 +/- 19%, p less than 0.01; Ran, 176 +/- 21% versus 232 +/- 29%, p less than 0.05) during the first 4 h after drug intake. A similar effect was observed in the morning period from 0600 to 1000 h (Fam, 118 +/- 19% versus 206 +/- 19%, p less than 0.001; Ran, 133 +/- 21% versus 207 +/- 31%, p less than 0.02). During the nighttime there were no significant differences. These findings indicate that smoking impairs the response to both drugs tested.

Enprostil reduces the increase of gastric corpus mucosal mass induced by the hydrogen-potassium-stimulated adenosine triphosphatase inhibitor BY 831-78 in the rat

We studied whether enprostil, a synthetic prostaglandin E2 derivative, might inhibit gastrin release and the trophic effects on gastric oxyntic mucosa induced by prolonged treatment with an inhibitor of hydrogen-potassium-stimulated adenosine triphosphatase, the substituted benzimidazole BY 831-78. Rats were treated intragastrically with enprostil (1 or 15 micrograms/kg b.i.d.), BY 831-78 (15 mumol/kg once daily), the combination of enprostil and BY 831-78, ranitidine (300 mumol/kg b.i.d.), and placebo. Plasma gastrin and somatostatin levels and gastric acid secretion were measured during a 1-day treatment in animals fitted with chronic gastric fistulas and repeatedly during 9 wk of treatment in intact rats. Despite inhibiting acid secretion, enprostil did not increase plasma gastrin. When combined with BY 831-78, enprostil transiently reduced the BY 831-78-induced increase of integrated plasma gastrin (1375 +/- 206 vs. 2137 +/- 256 pmol/L.12 h, p less than 0.05) in fasted rats with fistulas, but failed to prevent the marked hypergastrinemia following 9 wk of treatment with BY 831-78 (717 +/- 80 vs. 731 +/- 56 pmol/L) in intact rats. However, enprostil reduced the BY 831-78-induced increase of oxyntic mucosal volume (458 +/- 31 vs. 567 +/- 33 mm3, p less than 0.01), whereas BY 831-78 prevented the enprostil-induced increase of antral mucosal volume (42 +/- 3 vs. 56 +/- 3 mm3, p less than 0.01). These results demonstrate that some of the trophic effects induced by a hydrogen-potassium-stimulated adenosine triphosphatase inhibitor are not exclusively governed by gastrin.

Early dinner reduces nocturnal gastric acidity

This study examines whether eating food at different times has differential effects on intragastric pH. Experiments were done in 23 healthy volunteers (12 men). Intragastric acidity was monitored by ambulatory 22 hour pH-metry. Composition of meals was standardised: breakfast and lunch at 7 am and 12 noon respectively, and dinner at 6 or 9 pm, in random order. The time of going to bed and getting up was also standardised. With early dinner nocturnal pH was higher, than with late dinner (pH median: 1.67 and 1.39, p less than 0.001). During the remaining time periods, pH values were similar. Thus early dinner may be helpful in conditions where low intragastric acidity is desirable.

[Clozapine-induced cholestatic jaundice: a case report]

We report on a patient who became jaundiced during treatment with clozapine (Leponex). Histologically, cholestatic hepatitis with single-cell necroses of hepatocytes and infiltration of the portal zones with eosinophilic granulocytes were found. The patient recovered after discontinuation of clozapine, and liver function tests returned to normal within 4 weeks. This adverse effect of clozapine suggests that this "atypical" tricyclic neuroleptic resembles the phenothiazines both with regard to therapeutic spectrum and side effects.

Sucralfate and ranitidine in the treatment of acute duodenal ulcer. Healing and relapse. Ulcer Study Group

Healing and relapse of acute duodenal ulcer were investigated in an endoscopically controlled multicenter study using a double-blind design. Patients with acute uncomplicated duodenal ulcer were randomly assigned to treatment with sucralfate (1 g four times per day) or ranitidine (150 mg twice per day) for four to eight weeks. After healing, all anti-ulcer treatment was discontinued except for low-dose antacids needed for occasional upper abdominal pain, and the patients were observed for up to one year. Endoscopy was repeated after one year or at any time earlier if symptoms suggested ulcer relapse. Of the 83 patients who entered the study, 75 (sucralfate 40, ranitidine 35) underwent endoscopy after four weeks and could be fully evaluated. Healing rates after four and eight weeks were similar in the two groups (four- and eight-week healing rates after sucralfate and ranitidine: 78 and 74 percent, and 95 and 94 percent, respectively). Fifty-three patients with healed ulcers (sucralfate 29, ranitidine 24) were observed for up to one year. Duodenal ulcers occurred somewhat later after sucralfate than after ranitidine treatment, but life table analysis showed no significant difference. Thus, this study confirms a similar efficacy of sucralfate and ranitidine in healing of duodenal ulcer. A tendency to delayed relapse early after discontinuation of sucralfate failed to reach statistical significance.

Influence of prostaglandins, omeprazole, and indomethacin on healing of experimental gastric ulcers in the rat

We investigated whether the trophic actions of prostaglandins, omeprazole, and indomethacin on gastric mucosa lead to accelerated healing of gastric ulcers in the rat. Cryoulcers were produced in the corpus area and treated with 16,16-dimethyl prostaglandin E2 (5 or 100 micrograms/kg b.i.d., intragastrically), omeprazole (40 mumol/kg once daily, subcutaneously), indomethacin (2 mg/kg b.i.d., subcutaneously), or placebo. At the end of the treatment, plasma gastrin, cell labeling index (autoradiography with [3H]thymidine), and the size and depth of mucosal defects were measured. Compared with placebo, omeprazole accelerated ulcer healing as indicated by a smaller ulcer area [1.1 +/- 0.2 vs. 4.8 +/- 1.2 mm2 (mean +/- SEM)] and smaller ulcer depth (383 +/- 31 vs. 488 +/- 41 microns) after 10 days of treatment. Prostaglandins did not affect ulcer healing despite thickening of gastric corpus mucosa. Indomethacin delayed ulcer healing and reduced the labeling index. Omeprazole induced a marked hypergastrinemia (208 +/- 12 vs. 66 +/- 12 pmol/L on day 5, and 469 +/- 23 vs. 58 +/- 16 pmol/L on day 10). The results indicate that abolishment of acid secretion by omeprazole accelerates healing. Trophic actions and "cytoprotective" effects by prostaglandins are not relevant for ulcer healing in this model.

Prophylactic treatment of acute gastroduodenal stress ulceration. Low-dose antacid treatment without and with additional ranitidine

Low-dose antacid treatment without and with additional ranitidine in the prevention of acute gastroduodenal stress ulceration in high-risk patients was compared in a randomized, double-blind clinical trial with endoscopic examination of the upper gastrointestinal tract before entry and after the 7-day study period. Of 67 patients who entered the study, 56 could be evaluated. Only one patient, allocated to antacid and placebo, had massive acute upper gastrointestinal bleeding, arising from a gastric ulcer. Although gastric intraluminal pH was better controlled with additional ranitidine treatment, the occurrence of mucosal lesions did not depend on the assigned treatment. We conclude that there is no significant difference between the two regimens in terms of endoscopically visible lesions and clinical outcome.

Effect of 16,16-dimethyl prostaglandin E2 on small intestinal mucosa in suckling rats

Suckling rats were treated every 8 h by intragastric instillation of 16,16-dimethyl prostaglandin E2 (PG) in a dose of 25 micrograms kg-1 (PG25), or 100 micrograms kg-1 (PG100), or saline from postnatal day 7-11. PG increased small intestinal villus length and crypt depth, most markedly in the duodenum, leading to a mucosal height of 543 +/- 24 microns after saline, 670 +/- 26 microns after PG25 and 823 +/- 40 microns after PG100. In the proximal small bowel, PG100 raised the mean activities of sucrase by 439%, maltase by 98%, trehalase by 584%, lactase by 58% and alkaline phosphatase by 76%. In the distal small intestine, only sucrase and trehalase activities were stimulated whereas other enzymes were depressed. PG25 caused similar but less pronounced changes of enzyme activities. Eight hours after both the last PG25 and the last PG100 dose, plasma gastrin and corticosterone levels were decreased while thyroxine remained unchanged. The effect of a single dose of 100 micrograms kg-1 PG or saline was also tested on 5- and 11-day-old rats; they were killed 16 h after PG administration. An increase in villus length occurred along the entire small intestine of rats treated on day 5, and also in the ileum of rats treated on day 11. In the proximal intestine, maltase and trehalase were stimulated after early and late treatment and, in addition, sucrase and lactase after late treatment. Serum corticosterone levels were found to be significantly higher 2-6 h after PG100 than in the controls and then decreased gradually.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of prostaglandins on the adult rat stomach and intestine

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It is wise to prescribe NSAIDs with modern gastroprotective agents?

The administration of non-steroidal anti-inflammatory drugs (NSAIDs) leads to mucosal lesions in the upper gastrointestinal tract. Furthermore, NSAIDs increase the risk of ulcer bleeding and perforation, but the overall risk of fatal complications is relatively small (about 21 per one million prescriptions). Therefore, in asymptomatic patients, it is not justified to prescribe NSAIDs together with gastroprotective agents. The following recommendations can be given with respect to the management of peptic lesions in patients taking NSAIDs: (i) Fibre endoscopy should be performed even when there are relatively mild symptoms since mucosal lesions in rheumatic patients under NSAIDs produce minor or no symptoms. (ii) "Modern" NSAIDs might produce less gastric lesions than aspirin. (iii) Rheumatic patients with peptic disorders should be treated with an H2-antagonist. (iv) After complications such as ulcer bleeding or after rapid recurrence of peptic lesions, maintenance treatment with an H2-antagonist is advisable.

Healing and relapse of reflux esophagitis during treatment with ranitidine

In 108 patients the healing and relapse of reflux esophagitis, defined endoscopically by the presence of epithelial defects (erosions and ulcerations) of the esophageal mucosa, were studied. In the first study, with open treatment of ranitidine, the healing rate after 6 wk was 50%. The most important factor that negatively influenced healing was the extent of esophageal erosions. Patients with isolated erosions had a 6-wk healing rate of 78%; the healing rate was 38% in patients with longitudinally confluent lesions and 23% in those with circumferential erosions of the distal esophagus. Smoking also had an unfavorable effect. Age, sex, duration of history, body weight, and alcohol consumption were not related to outcome. Symptoms improved during treatment with ranitidine, but the correlation between symptoms and endoscopic findings at 6 wk was weak. In the second study, relapse was investigated in 61 patients with healed esophagitis in a randomized, double-blind trial comparing placebo and ranitidine (150 mg at bedtime for 6 mo). In both groups, relapse occurred in more than one-third of the patients, with no significant difference between ranitidine and placebo treatment. Patients with worse daytime symptoms at the time of previous healing had a higher relapse rate. The initial severity of esophagitis and smoking did not influence recurrence. Thus, the initial endoscopic findings are of prognostic value in reflux esophagitis. Smoking retards healing. Low-dose maintenance treatment with ranitidine does not prevent relapse.

Indomethacin and turnover of gastric mucosal cells in the rat

Mucosal morphology and the balance between cell loss and cell renewal were analyzed during treatment with a non-ulcerative dose of indomethacin. All rats were treated twice daily by subcutaneous injection of 2 mg/kg indomethacin or the solvent. The following parameters were assessed: cell proliferation on day 3 (determination of in vitro [3H]thymidine incorporation), cell migration on days 1 and 3 (autoradiography), cell shedding on days 7 and 14 (measurement of the remaining DNA-bound mucosal radioactivity after in vivo labeling with [3H]thymidine prior to treatment), mucosal morphology on day 14 (light microscopy), ex vivo mucosal prostaglandin E2 on day 14, and serum gastrin on days 0, 7, and 14. Indomethacin treatment had no effect on serum gastrin levels but reduced mucosal prostaglandin E2. Indomethacin produced a significant increase of [3H]thymidine incorporation, cell migration, and loss of mucosal DNA-bound radioactivity in the corpus and, to a lesser degree, in the antrum. Morphologically, this led to a hyperplasia of parietal cells (+15%, P less than 0.05) and chief cells (+45%, P less than 0.01) in the corpus, but antral morphology remained unchanged. We conclude that indomethacin stimulates the turnover of gastric mucosal cells. In the corpus, but not in the antrum, proliferation exceeds shedding, thus leading to increased mucosal volume.

Effect of acid inhibition on the growth of parietal cells

Studies in the rat have shown that prolonged inhibition of acid secretion by high doses of a histamine H2 antagonist is followed by a 20-30% increase in the number of parietal cells, and that this is paralleled by an augmentation of the maximum acid output. A similar effect has been shown after prolonged acid neutralization with high doses of an antacid. These trophic effects are not unexpected. An increase in gastric pH is followed by gastrin release, and the parietal cell mass may be augmented by repeated exogenous administration of gastrin or by endogenous hypergastrinaemia following surgery. To further evaluate whether a direct correlation exists between the magnitude of drug-induced hypergastrinaemia and parietal cell hyperplasia, rats were treated for 24 days with two acid inhibitors which differ markedly in the degree of acid inhibition and acute or chronic gastrin release. Six animals each were treated with either omeprazole (40 mumol/kg once daily), or atropine (3 mg/kg twice daily), or omeprazole combined with atropine or with placebo. On day 24, plasma gastrin was elevated more than 10-fold in both groups of rats treated with omeprazole but not in animals given atropine alone. As compared to placebo treatment, total parietal cell volume was significantly higher in animals treated with atropine (102 +/- 9 mm3 versus 140 +/- 18 mm3), but was unchanged in the other two groups. These studies demonstrate that marked prolonged drug-induced hypergastrinaemia does not necessarily exert trophic effects on parietal cells. Furthermore, the finding that omeprazole abolishes the effect of atropine suggests that omeprazole interferes with trophic actions on parietal cells.

Protective drugs in the treatment of gastroduodenal ulcer disease

Reduction of gastric acidity by the inhibition of secretion or neutralization is the therapeutic principle most widely used in peptic ulcer disease. From a pathophysiological standpoint, this does not appear logical, because in a majority of patients gastric acid secretion is not increased. In addition, there is some concern about the consequences of a reduction in gastric acidity, especially in the long term. And finally, all available inhibitors of gastric acid secretion have a systemic action and may thus cause systemic side effects. Carbenoxolone, sucralfate, and tri-potassium dicitrato bismuthate have been shown to accelerate healing of ulcers without appreciable acid inhibition. Despite an apparently different mode of action, the healing rates are similar to those of commonly used acid inhibitors. Several possible mechanisms of action have been claimed for each of these agents, but none has been convincingly demonstrated to be essential in ulcer healing. This may reflect ignorance of the relevant events rather than an action by a combined principle.

Clinical relevance of mucosal protection

An inquiry was made among 70 of the 76 participants of an international symposium entitled 'Future Directions in Peptic Ulcer Research', held in Bellagio, Italy, in April 1986. There was almost unanimous agreement that research in the development of protective drugs should be intensified. The participants felt that in future studies the prevention of ulcer relapse, concomitant administration with potentially ulcerogenic drugs, prevention of stress ulceration, and treatment of ulcer hemorrhage should be emphasized rather than the healing of uncomplicated ulcers. They were not generally satisfied with the performance of available prostaglandin analogues in ulcer treatment. The moderate commercial success of sucralfate was attributed mainly to the complicated mode of intake, but also to the unknown mechanism of action of this substance. It was felt likely that antacids have a clinically relevant protective effect on gastroduodenal mucosa.

Structure and function of gastric corpus mucosa in suckling rats after treatment with 16,16-dimethyl prostaglandin E2

Suckling rats were treated every 8 h by intragastric instillation of 16,16-dimethyl prostaglandin E2 (PG) from postnatal day 7 to 11. As compared to saline control treatment, PG increased the thickness of antral and corpus mucosa, the volume density of parietal cells, the mean individual parietal cell volume and pentagastrin-stimulated acid secretion at the end of the treatment. Plasma gastrin and corticosterone levels were depressed by PG while plasma thyroxine levels were unchanged. These structural and functional changes suggest PG-induced accelerated maturation of gastric mucosa.

Influence of 16,16-dimethyl prostaglandin E2 on morphology and brush border enzymes of small-bowel mucosa. Differences in reactivity between adult and suckling rats

High doses of 16,16-dimethyl prostaglandin E2 (dmPGE) are trophic to the small bowel of adult and suckling rats. In suckling rats this effect is paralleled by an increase in brush border enzyme activities, possibly indicating accelerated mucosal maturation. To investigate the possible physiological significance of this phenomenon, we examined whether this induction of intestinal enzyme activities can be reproduced in adult rats and whether cell growth and enzyme activity might be suppressed by indomethacin. Treatment twice daily for 2 weeks with 100 micrograms/kg dmPGE by intragastric instillation increased villus length in the proximal and distal small bowel by 36% and 40%, respectively, while 2 mg/kg indomethacin by subcutaneous injection had no effect. Maltase, trehalase, lactase, and sucrase activities were unchanged after dmPGE or indomethacin. [3H]-thymidine incorporation into DNA was not significantly influenced for up to 24 h after a single dose of both 100 micrograms/kg PGE intragastrically or 10 mg/kg indomethacin subcutaneously. These studies confirm that in adult rats large doses of 16,16-dm PGE2 increase the volume of the small-bowel mucosa. In contrast to the situation in suckling rats, the activity of hydrolytic brush border enzymes is not increased. There is thus no evidence that endogenous prostaglandins are trophic or influence brush border enzymes in the adult rat.