Randomised crossover trial of tripotassium dicitrato bismuthate versus high dose cimetidine for duodenal ulcers resistant to standard dose of cimetidine

Pylera for the eradication of Helicobacter pylori infection

An ideal antibiotic regimen for Helicobacter pylori should achieve eradication rates of approximately 90%. Current 7-day triple therapy is successful in about two-thirds of patients. A novel treatment is required to achieve higher eradication with minimal induction of bacterial resistance. The aim of this article is to evaluate the safety and efficacy of a single triple capsule (Pylera) containing bismuth, metronidazole and tetracycline, given with omeprazole for the eradication of H. pylori infection. Extensive literature searches were conducted using PubMed data from 1982 to 2007. This search included headings of H. pylori, bismuth and eradication therapy. The triple capsule Pylera, when given with omeprazole, achieved eradication rates ranging between 84 and 97%. Eradication rates were similar for clarithromycin- and metronidazole-resistant strains. Eradication rates with an omeprazole, bismuth, metronidazole and tetracycline regimen appeared comparable for metronidazole-resistant and -sensitive strains. This effect is not seen with the use of triple therapy in cases of clarithromycin resistance. Clinical trials did not report any serious side effects from bismuth-based regimens and compliance was similar to standard triple therapy. Bismuth-based triple therapy using Pylera is a simplified, effective and well-tolerated regimen achieving cure rates of above 90%.

What is an intractable duodenal ulcer and how should it be managed?

An intractable duodenal ulcer is an ulcer that has not healed after 8 weeks of full-dose treatment with a modern anti-ulcer drug. Such ulcers are relatively rare--perhaps five in 100 patients will have intractable duodenal ulceration. The differential diagnosis includes non-compliance as a cause of continuing ulceration, hypersecretion of gastric acid or other rare causes of ulcers in the duodenum. Investigations should include biopsy of the continuing ulceration at endoscopy, measurement of fasting plasma gastrin and routine haematology and biochemistry profiles. An intractable duodenal ulcer can be treated either by using a powerful antisecretory regimen (high doses of ranitidine or famotidine or a conventional dose of omeprazole), by changing to tripotassium dicitrato bismuthate or, in exceptional circumstances, by extremely careful surgical intervention.

Helicobacter pylori: review of research findings

Helicobacter pylori attracted widespread interest from gastroenterologists because of its potential aetiologic role in disorders of the upper gastrointestinal tract. Based on extensive microbiological studies, Campylobacter pylori was renamed Helicobacter pylori, and the organism represents a new genus of bacteria. It is generally accepted that H. pylori causes chronic, non-specific gastritis (type B gastritis). The inflammatory response occurs even though the bacterium does not penetrate the gastric epithelium; it is found on the surface of and adjacent to the epithelium. The clinical significance of histological gastritis is unknown. The bacterium is often found in asymptomatic subjects. In Caucasian adults, the prevalence of infection increases with increasing age. Higher rates of infection are found in blacks and Hispanics than would be expected for their age. Whether these different rates are the result of racial or socioeconomic factors is not known. It is theorized, but not proven, that high rates of infection with H. pylori at an early age may explain the high incidence of gastric carcinoma found in Hispanic populations. H. pylori is found in almost every patient with duodenal ulcer disease, although no direct evidence for a causal relationship exists. Indirect evidence is based on the findings that if H. pylori infection is eradicated, ulcer recurrence is less likely (up to one year of follow-up). A small percentage of patients have a relapse despite eradication of the organism, suggesting a role for other factors in duodenal ulcer disease. The role of H. pylori in gastric ulcer disease is unknown. Seventy to eighty per cent of patients with gastric ulcer have evidence of H. pylori infection, and preliminary data seem to support the existence of two distinct aetiologic groups: those with gastric ulcers related to H. pylori infection and those with gastric ulcers related to use of non-steroidal anti-inflammatory drugs. The role of H. pylori in non-ulcer dyspepsia is unknown. Some clinicians believe that H. pylori causes non-ulcer dyspepsia and treat these patients for H. pylori infection. However, the data supporting this practice are poor. Treatment is only recommended for patients with resistant duodenal ulcers and patients who have frequent relapses of duodenal ulcers and who are willing to take triple-drug therapy (bismuth compounds, metronidazole, tetracycline) for the infection. As 95% of patients with duodenal ulcer have evidence of H. pylori infection, there is probably little need to confirm the diagnosis of H. pylori infection.

What are the current possibilities in treating peptic ulcer disease?

There are two major principles of ulcer therapy. Today, the most widely accepted drugs are those which substantially reduce aggressive factors (i.c. acid and pepsin), namely histamine H2-receptor antagonists, antimuscarinics and antacids. Less frequently applied are mucoprotective agents like colloidal bismuth compounds and sucralfate. Prostaglandins both reduce acid secretion substantially and are believed to enhance mucosal resistance. Their anti-ulcer efficacy, however, is solely explicable by their antisecretory activity. Although mucosa-strengthening agents and H2-receptor blockers have nearly identical healing rates, mucosa-strengthening agents have inconvenient dosage regimens (four times or twice daily) and are probably less effective in relieving pain. The same holds true for antacids. Prostaglandins, antimuscarinics and antacids have dose related side effects. In contrast, H2-receptor blockers are characterized by a clear mechanism of action, convenient dosage regimens, good tolerance and a low incidence of side-effects. H2-receptor antagonists are the most effective anti-ulcer drugs presently available.

Systematic review and meta-analysis: is 1-week proton pump inhibitor-based triple therapy sufficient to heal peptic ulcer?

AIMS

To systematically review the efficacy on ulcer healing of 1-week combination of a proton pump inhibitor plus two antibiotics and to perform a meta-analysis of randomized clinical trials to evaluate whether 7 days of proton pump inhibitor-based triple therapy is sufficient to heal peptic ulcer.

METHODS

Studies where 1-week proton pump inhibitor-based triple therapy was administered to heal peptic ulcer were included. Randomized clinical trials comparing the efficacy on ulcer healing of 7-day proton pump inhibitor-based triple therapy versus this same regimen but prolonging the proton pump inhibitor for several more weeks were included in the meta-analysis. Electronic and manual bibliographical searches were conducted. Meta-analysis was performed combining the odds ratios of the individual studies.

RESULTS

Twenty-four studies (2342 patients) assessed ulcer healing with 1-week proton pump inhibitor-based triple therapy. Mean healing rate was 86%, and 95% in Helicobacter pylori-eradicated patients. Six studies (862 patients), were included in the meta-analysis. Mean ulcer healing rate with a 7-day treatment was 91% versus 92% when proton pump inhibitor was prolonged for 2-4 more weeks (odds ratio = 1.11; 95% confidence interval = 0.71-1.74).

CONCLUSION

In patients with peptic ulcer and H. pylori infection, prolonging therapy with proton pump inhibitor after a triple therapy for 7 days with a proton pump inhibitor and two antibiotics is not necessary to induce ulcer healing.

Unhealed duodenal ulcers despite Helicobacter pylori eradication

BACKGROUND

Our aims were 1) to study the influence of several factors (age, sex, smoking, previous ulcer disease, ulcer size, chronic gastritis, serum gastrin and pepsinogen I levels, therapy regimen and, especially, eradication of Helicobacter pylori) on duodenal ulcer healing; 2) to evaluate the frequency of duodenal ulcer healing failure despite eradication of H. pylori, to study why this failure occurs, and to verify its evolution without antisecretory therapy; and 3) to confirm whether a week's prescription of omeprazole is sufficient to obtain ulcer healing.

METHODS

Three-hundred and eight patients (mean age, 45 +/- 13 years; 71% males) with duodenal ulcer and H. pylori infection were studied prospectively. Biopsy specimens were obtained at initial endoscopy, and serum gastrin and pepsinogen I levels were measured. A repeat endoscopy (with biopsies) was performed 1 month after eradication therapy had been completed, and a 13C-urea breath test was also carried out. Three eradication therapies were used: omeprazole plus amoxycillin for 2 weeks (OA group, n = 61); 'classic' triple therapy (with bismuth; CTT group, n = 65); and 'new' triple therapies for 1 week (NTT group, n = 182): omeprazole plus two of the following antibiotics: clarithromycin, metronidazole, and amoxycillin. When the ulcer did not heal despite successful H. pylori eradication, antacids were prescribed on an as-needed basis, and endoscopy was repeated 1 month later (2nd control endoscopy). If the ulcer was still present, the acid output (basal and pentagastrin-stimulated) was measured, a secretin test was performed, and a final endoscopy (3rd control endoscopy) was carried out after an additional month. The statistical method used was multiple logistic regression.

RESULTS

Overall eradication was achieved in 69% (n = 212) of the patients, and ulcer healing in 76% (n = 233): 57% in the OA group, 80% in the CTT group, and 81% in the NTT group (P < 0.01 when comparing the OA group with the others). Ulcer healing was achieved in 90% of H. pylori-eradicated patients and in only 45% of patients with eradication therapy failure (P < 0.001). Similar results were obtained when only patients treated with NTT were considered: ulcer healing in 90% of patients with the organisms eradicated. Eradication of H. pylori (odds ratio (OR), 11.8; 95% confidence interval (CI), 6.3-22) and sex (OR, 2.5; 95% CI, 1.2-5.1) were the only variables that correlated with ulcer healing in the multivariate analysis. The ulcer persisted despite successful eradication of H. pylori in 22 patients. The duodenal ulcer had healed spontaneously in 73% of these patients at the 2nd control endoscopy. Finally, by the 3rd control endoscopy, only three patients still had duodenal ulcer. Therefore, ulcer healing was finally achieved in 98.1% (95-99%) of patients in whom H. pylori was eradicated. Gastrin, pepsinogen I, acid output, and the secretin test had normal values in all patients.

CONCLUSIONS

Eradication of H. pylori favours ulcer healing, which is achieved in most patients in whom the organism is eradicated. Just 1 week of omeprazole therapy (that is, the antibiotic administration period in the new triple therapies) is enough to obtain a high ulcer healing rate. Most duodenal ulcers that do not heal initially despite H. pylori eradication will ultimately do so after several weeks without additional therapy.

Healing of gastric body ulcer with gastroprotective versus antisecretory treatment

The aim of this study was to compare the healing effect of a gastroprotective agent and antisecretory drugs in gastric body ulcer where failure of the mucosal defense might be an important factor. Eighty-five patients with benign gastric ulcer were divided into four groups: treated with antacids (I), cimetidine (II), ranitidine (III), and colloidal bismuth subcitrate (De-Nol) (IV). Endoscopically confirmed complete healing was achieved in 57, 61, and 63% in groups I, II, and III, respectively, and in 88% in group IV (P < 0.05). Gastric secretion did not change significantly. Relapses during the next three years occurred several times more frequently in groups I, II, and III than in group IV. Helicobacter pylori was positive in about half the relapsing patients in groups I, II, and III but negative in those of group IV. It is concluded that De-Nol treatment of gastric body ulcer was more efficient than antisecretory drugs both initially and in reducing relapses.

Helicobacter pylori in Melbourne Chinese immigrants: evidence for oral-oral transmission via chopsticks

The Helicobacter pylori seroprevalence in a representative population of 328 Melbourne Chinese immigrants (162 men and 166 women) aged 25 years and older were studied. The population consisted of Chinese people born in China/Hong Kong (n = 110, 33.5%), Vietnam (n = 79, 24.1%), Malaysia/Singapore (n = 102, 31.1%), and elsewhere (n = 37, 11.3%). The overall seroprevalence of H. pylori was 59.5%; 60.5% in men and 58.4% in women. Gender specific analysis showed associations between higher seroprevalence and several socio-demographic factors; in men, age (P < 0.0001), lower education level (P < 0.002), cigarette smoking (P < 0.042), the use of antibiotics (P < 0.015) and chopsticks (P < 0.047), and in women, lower socioeconomical status [education level (P < 0.030), gross household income (P < 0.0001) and occupational status (P < 0.0001)] and use of chopsticks (P < 0.002). Seroprevalence differed between immigrants of various birthplaces (P < 0.001); those born in Malaysia/Singapore (43.1%) were lower than those born in China/Hong Kong (68.2%), Vietnam (68.4%), and elsewhere (59.5%). Immigrants of various birthplaces also differed in their pattern of socio-demographics. Multivariate analyses showed that risk factors for H. pylori infection within the Melbourne Chinese immigrants were, in men, age (B = 1.081) and birthplace (B = 1.769) and, in women, household income (B = 0.541) and use of chopsticks (B = 1.654). This study suggests person-to-person transmission of H. pylori via the oral-oral route with ethno-specific food practices an important risk factor.

Duodenal ulcer treatment: progress from pH to HP

The treatment of duodenal ulcer has evolved from ineffective medical treatments through an era of surgical management, back to increasingly effective medical treatment. The advent of H2-receptor antagonists changed the outlook for ulcer patients. More recently, Helicobacter pylori, an organism which inhabits gastric mucosa exclusively, has been implicated in the pathogenesis of peptic ulcer. This bacterium is found in the stomachs of around 95% of duodenal ulcer patients. Its eradication is shown dramatically to improve the rate at which ulcers relapse. The mechanisms whereby it may cause ulceration are not established--we review current hypotheses. No method of eradication is 100% effective, and many different dual or triple therapy regimens have been tried. Metronidazole resistance is reported but its importance is not yet known. Helicobacter eradication is likely to prove a cost-effective and acceptable treatment for duodenal ulcer, and once its value has gained acceptance widespread uptake of this option is anticipated.

Short and long term outcome of Helicobacter pylori positive resistant duodenal ulcers treated with colloidal bismuth subcitrate plus antibiotics or sucralfate alone

Thirty two patients with Helicobacter pylori positive duodenal ulcers resistant to treatment were randomly assigned to 4 weeks' treatment with sucralphate 4 g/day or colloidal bismuth subcitrate 480 mg/day plus amoxycillin from days 1 to 7 and tinidazole from days 8 to 14. After 4 weeks, patients with unhealed ulcers were crossed over to the other form of treatment for a further 4 week period. Patients with healed ulcers were followed up for 1 year without maintenance therapy with clinical and endoscopic investigations 3, 6, and 12 months after healing. Complete healing rates at 4 weeks were 88% (15 of 17) in the colloidal bismuth subcitrate plus antibiotics group and 40% (six of 15) in the sucralphate group (p < 0.05). After cross over, overall healing rates were 88% (22 of 25) and 47% (eight of 17), respectively (p < 0.05). H pylori eradication occurred in 83% of patients treated with the triple therapy. Cumulative relapse rates at 12 months were 12% (two of 17) in patients in whom H pylori had been eradicated and 100% (10 of 10) in those with persistent infection after short term therapy (p < 0.05). These results show that a colloidal bismuth subcitrate plus antibiotics regimen is highly effective in the short term treatment of resistant duodenal ulcers and that H pylori eradication can change the natural tendency to early recurrence of these ulcers.

Bismuth subsalicylate in the treatment of H2 blocker resistant duodenal ulcers: role of Helicobacter pylori

Fifty nine patients with Helicobacter pylori positive duodenal ulcers that failed to heal after a six week course of treatment with H2 blockers were randomly assigned to one of the following three regimens: (i) bismuth subsalicylate, 600 mg three times daily (n = 19), (ii) ranitidine, 300 mg at night (n = 20), (iii) bismuth subsalicylate plus ranitidine (n = 20). Cumulative ulcer healing rates after four and eight weeks respectively were as follows: bismuth subsalicylate 74% (14/19) and 95% (18/19), ranitidine 40% (8/20) and 65% (13/20), bismuth subsalicylate plus ranitidine 80% (16/20) and 95% (19/20). Bismuth subsalicylate treatment was better than ranitidine at both four and at eight weeks (p less than 0.05). The clearance rates for H pylori after four weeks were: bismuth subsubsalicylate 58%, ranitidine 0%, bismuth subsalicylate plus ranitidine 55%. After stopping bismuth therapy bacterial recrudescence frequently occurred. After bismuth treatment 86% (19/22) of ulcers had healed if H pylori had been cleared, whereas only 65% (11/17) had healed if H pylori persisted (NS). This study shows that bismuth subsalicylate is more effective in the treatment of resistant duodenal ulcers than standard dose ranitidine. It may be that suppression of H pylori by bismuth subsalicylate promotes ulcer healing.

Treatment of refractory peptic ulcer with omeprazole or continued H2 receptor antagonists: a controlled clinical trial

We tested the hypothesis that the gastric H+/K+ adenosine triphosphatase inhibitor, omeprazole, because of its different mode of action and pronounced inhibitory effect on gastric acid secretion, may be more effective in peptic ulcer that is refractory to histamine H2 receptor antagonist treatment than continuing the same therapy. Altogether 107 patients (duodenal ulcer, n = 88; prepyloric ulcer, n = 14; gastric ulcer, n = 3; mixed sites, n = 2) with refractory peptic ulcer - that is ulcer unhealed after at least two months' treatment with cimetidine 0.8 g or 1 g daily or with ranitidine 0.3 g daily - were randomly allocated to receive either omeprazole 40 mg daily (n = 54) or to continue treatment with the same H2 receptor antagonist and at the same dose (n = 53) for up to eight weeks. The patients in the two treatment groups were well matched demographically. Healing by 'intent to treat' analysis was as follows: at four weeks, omeprazole 46 of 54 (85%), H2 receptor antagonist 18 of 53 (34%) (p less than 0.0001); and at eight weeks, 52 of 54 (96%) and 30 of 53 (57%) respectively (p less than 0.0001). One patient was lost to follow up but of the 22 patients whose ulcers were shown to be unhealed at endoscopy after receiving continued H2 receptor antagonist treatment, 21 healed in four to eight weeks when changed to omeprazole. Daytime epigastric pain cleared at four weeks in 43 of 47 (91%) patients on omeprazole and in 32 of 46 (70%) on H2 receptor antagonists (p=0.01) and relief of all dyspeptic symptoms occurred in 39 of 47 (83%) and 23 of 45 (51%) (p=0.0009) patients respectively. Adverse events occurred in 11 of 54 (20%) patients on omeprazole and in 12 of 35 (34%) on cimetidine but in none on ranitidine. The events were mild and none required treatment withdrawal. The commonest event in patients on omeprazole was loose stools or diarrhoea (n=5). Omeprazole was significantly better than continued H2 receptor antagonist treatment for the short term management of refractory peptic ulcer as judged by healing rate and pain relief, and it was safe.

Peptic ulcer disease. How to treat it now

Options for treatment of peptic ulcer disease are becoming more diverse. Most new agents are effective yet offer no real advantage over more traditional therapy. However, omeprazole (Prilosec) may be of benefit owing to its potent inhibition of acid secretion, but it is not yet approved for this purpose. Whether treatment of Helicobacter pylori infection will prove beneficial is not yet known, but the answer should be forthcoming. Finally, as with any disease process, alleviation of risk factors is always important. Appropriate counseling regarding use of nonsteroidal anti-inflammatory drugs and cigarette smoking is a necessity.

Medical treatment of duodenal ulcer: acid inhibition or Helicobacter pylori eradication?

To ascertain whether acid inhibition or Helicobacter pylori (HP) colonization is the decisive factor in the healing of duodenal ulcer, we treated 54 patients with famotidine and carried out long-term follow-up. Helicobacter pylori colonization was found in 70.4% of patients before treatment. There were no differences in the pre-treatment characteristics between patients with HP positive or HP negative ulcers. The 4-week and 8-week healing rates after famotidine treatment were 72.5% and 82.4% respectively. No difference in HP colonization was found between patients with ulcer healed and those with ulcer not healed (78.4% vs 64.3% at 4th week and 77.3% vs 71.4% at 8th week, P greater than 0.05). In patients with ulcer healed at 4th week, the intragastric pH was raised significantly and the antral acute inflammation was less severe than those with ulcer not healed. Ulcer recurrence was found in 76.9% of patients within 1 year, but there was no difference in ulcer recurrence between the patients with positive or negative HP colonization at the time of ulcer healing. Our results suggest that duodenal ulcer healing and recurrence are closely related to acid inhibition rather than to HP colonization.

Clinical indications and efficacy of colloidal bismuth subcitrate

Colloidal bismuth subcitrate (CBS; DeNol) has been studied in clinical trials investigating the treatment of duodenal and gastric ulcer, non-ulcer dyspepsia, duodenitis, non-steroidal anti-inflammatory drug (NSAID)-induced disease, and Helicobacter pylori-induced gastroduodenitis. Healing rates for duodenal ulcer with CBS are significantly better than with placebo and are similar to results obtained with cimetidine or ranitidine. CBS is significantly better in the treatment of duodenal ulcer resistant to standard doses of H2 antagonists than increased doses of H2 antagonists. Duodenal ulcer relapse at 12 months after initial healing with CBS is significantly less than with H2-antagonist therapy. Ulcer healing with CBS is not influenced by smoking. H. pylori eradication with CBS appears to have little effect in ulcer healing but is of major importance in preventing ulcer relapse. CBS is effective in combination with antibiotics in eradicating H. pylori-associated gastritis. In gastric ulcer disease CBS therapy resulted in significant healing advantages over placebo and was comparable to treatment with cimetidine and sucralfate. CBS has been shown to be effective in the treatment of erosive duodenitis. The role of CBS in treatment of non-ulcer dyspepsia and NSAID-induced damage awaits further clinical studies.

Bismuth therapy in gastrointestinal diseases

Bismuth therapy has shown efficacy against two major gastrointestinal disorders: peptic ulcer disease and diarrhea. In peptic ulcer disease it is as effective as the H2-receptor antagonists, costs considerably less, and offers a lower rate of relapse. When Helicobacter pylori is implicated, bismuth acts as an antimicrobial agent, suppressing the organism but not eliminating it. In recent studies, bismuth compounds have been used with conventional antibiotics, producing elimination of the organism, histological improvement, and amelioration of symptoms for periods longer than one year. Bismuth subsalicylate has shown modest efficacy in treating traveler's diarrhea and acute and chronic diarrhea in children, and it is effective prophylactically for traveler's diarrhea. An epidemic of neurological toxicity was reported in France in the 1970's with prolonged bismuth treatment, usually bismuth subgallate and subnitrate. Such toxicity has been rare with bismuth subsalicylate and colloidal bismuth subcitrate. However, recent studies have demonstrated intestinal absorption of bismuth (about 0.2% of the ingested dose) and sequestration of this heavy metal in multiple tissue sites, even occurring with conventional dosing over a 6-week period. These findings have inspired recommendations that treatment periods with any bismuth-containing compound should last no longer than 6-8 weeks, followed by 8-week bismuth-free intervals.

Changing pattern of admissions and operations for duodenal ulcer

The admission rates for duodenal ulcer (DU) and the effect of H2-receptor antagonists (H2RA), introduced in the Trent Region of the UK in 1977, were examined. The admission rates are expressed per 10(6) of resident population. The use of H2RA has risen 3.7-fold (from 1978 to 1983), yet overall admission rates for perforation have changed little: 99 in 1972-76 (pre-H2RA period) compared with 103 in 1977-84 (H2RA period). Admission rates for haemorrhage have risen by 8 per cent, from 130 to 140 (P less than 0.01). However, the overall rates conceal large increases (P less than 0.01) in the admission rates for those aged greater than or equal to 65 years, of 33 per cent (from 264 to 352) for perforation and of 28 per cent (from 381 to 489) for haemorrhage. Emergency admissions for uncomplicated DU were unchanged: 88 in 1972-76 and 89 in 1977-84. However, the proportions operated on fell by 58 per cent (P less than 0.01), from 30 per cent of admissions in the pre-H2RA period compared with only 12 per cent in the H2RA period. Waiting-list admissions for uncomplicated DU fell by 43 per cent, from 187 to 106 (P less than 0.01), and the proportions operated on fell from 162 to 76; the combined effect resulted in a reduction of 53 per cent in the operation rates (P less than 0.01). In Rotherham, the use of H2RA has risen 6.2-fold (from 1978 to 1983) and they were generally used intermittently in 1976-78 and later for maintenance therapy and high-dose treatment. Yet admissions for perforation and for haemorrhage were unchanged. Emergency admissions for uncomplicated DU rose by 40 per cent, from 130 in 1972-75 to 182 in 1976-84, but the proportions operated on fell markedly, from 20 to 6 per cent (P less than 0.01); waiting-list admissions fell in 1976-78 by 29 per cent and in 1979-84 by 73 per cent. The proportions operated on in the three periods fell from 74 to 53 per cent and 25 per cent respectively and these two factors led to decreases in elective surgery of 50 per cent in 1976-78 and 91 per cent in 1979-84 (P less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)

Omeprazole in the treatment of duodenal ulcer

Omeprazole is the most effective antisecretory agent available today. Open and dose-comparative studies have documented that at dosages of 20 mg/day or more, the drug produces duodenal ulcer healing rates of 90-100% after 4 weeks. Controlled trials show that omeprazole, 20-40 mg/day, is superior to cimetidine and ranitidine in healing duodenal ulcer, with a median therapeutic gain of 21% at 2 weeks and 15% at 4 weeks. Ulcer symptom relief is also more pronounced and faster with omeprazole than with H2-receptor antagonists. No significant side-effects attributable to treatment with omeprazole have appeared in any of these studies or in the accumulated experience from several thousand patients treated with omeprazole. No tendency to an increase in recurrence rate after discontinuation of treatment with omeprazole has been shown. In summary, omeprazole constitutes a major advance in the short-term treatment of duodenal ulcer, giving fast and pronounced healing and symptom relief.

Omeprazole in the management of refractory duodenal ulcer

In about 5-10% of duodenal ulcer patients, ulcer healing is difficult or impossible to achieve with H2-receptor antagonists. Such patients are considered to have a refractory ulcer. The cause of refractoriness remains unknown. Some patients have high acid secretion or inadequate acid suppression on treatment, but this has not been confirmed by all investigators or in all patients. Abnormalities in mucosal defence presumably exist, but none have as yet been identified. The principal medical therapeutic approach has been to continue suppressing acid or to use mucosal protective agents. Increasing the duration of H2-receptor antagonist treatment at the same dose had little effect, but doubling or trebling the dose improved healing rates in open studies. Markedly higher healing rates occurred when treatment was changed from cimetidine to ranitidine (which is more potent) in open studies, but this was not always confirmed in controlled studies. Adding the anti-muscarinic, pirenzepine, to cimetidine to achieve better acid inhibition, improved healing rates in some controlled studies but not in others. The mucosal protectant, colloidal bismuth subcitrate, proved significantly more effective than H2-receptor antagonist treatment, but the drug is suitable only for short-term therapy. Controlled studies with omeprazole confirmed the results of open studies and proved the product to be superior to continued H2-receptor antagonist treatment in healing refractory duodenal ulcer. Open studies using maintenance treatment with low-dose omeprazole suggest that such therapy is effective in keeping refractory duodenal ulcer healed.

Tripotassium dicitrate bismuthate and ranitidine in duodenal ulcer. Healing and influence on recurrence

One hundred patients were entered into a double-blind, double-dummy comparison of tripotassium dicitrate bismuthate (TDB) versus ranitidine, to evaluate short-term healing rates, and successfully healed patients were then entered into a follow-up phase to observe relapse rates. At 4 weeks 84% of patients treated with TDB and 68% of those treated with ranitidine had healed. At 8 weeks these figures had risen to 96% and 90%, respectively (p = NS). After a year's follow-up study 84% of patients healed initially with ranitidine had relapsed, whereas in the case of patients healed initially with TDB the relapse rate was 67% (p less than 0.05). The results confirm that in the short term, TDB is as effective as ranitidine, whereas the significantly better protection against relapse offered by TDB compared with ranitidine underlines the importance of restoring mucosal defence, an approach that to date has been somewhat overlooked.

Colloidal bismuth subcitrate. A review of its pharmacodynamic and pharmacokinetic properties, and its therapeutic use in peptic ulcer disease

Colloidal bismuth subcitrate (CBS) possesses at least equal efficacy with histamine H2-receptor antagonist drugs in the treatment of peptic ulcer disease. However, CBS has the advantage of slower ulcer relapse rates than those seen after initial healing with the H2-antagonists. It has been postulated that this effect may be partly due to the antibacterial properties of CBS against Campylobacter pylori, a bacterium found in the gastric mucosa and gastric metaplasia within the duodenum of most patients with peptic ulcer and closely associated with gastritis. However, the role of C. pylori in the aetiology of peptic disease is far from clear. The mechanism by which CBS heals ulcers has not been fully elucidated, but several actions may be involved. CBS and mucus form a glycoprotein-bismuth complex in vitro. This provides a diffusion barrier to HCl and may, therefore, provide a protective coating in the ulcer crater which allows healing of the lesion to occur. Prostaglandin E2 production is also stimulated by CBS with subsequent secretion of alkali into the mucus layer. In addition, CBS has a direct inhibitory effect on C. pylori. Administration of CBS results in low levels of bismuth absorption. Most of the ingested bismuth is excreted as bismuth sulphide, causing blackening of the faeces, and the small amount absorbed is excreted in the urine. Bismuth intoxication (encephalopathy) has been reported with prolonged administration of bismuth salts, and there has been 1 report of similar intoxication in a patient receiving unusually high doses of CBS for a prolonged period. However, no such intoxication has been reported with CBS used at its recommended dosage in the acute treatment of peptic ulcer disease, and no other serious adverse effects have been associated with CBS. Tissue accumulation during prolonged therapy seems likely, and the safety of CBS during long term maintenance therapy has not been established. The lack of effect on gastric acid secretion is seen as an added advantage for CBS, since prolonged drug-induced hypochlorhydria has been postulated to have potentially detrimental effects. Thus, while the role of C. pylori in peptic ulceration requires further clarification, CBS would appear to have an important place in the treatment of peptic ulcer disease with the advantage of relatively slow relapse rates after initial healing and treatment discontinuation.

Histamine H2-receptor antagonists

The first histamine H2-receptor antagonists were developed in the early 1970s, and they have a dominant role in today's management of peptic ulceration. The original regimens using either cimetidine or ranitidine attempted to control acidity across the 24 hours, but more 'modern' regimens use a large single dose of the H2-blocker in the evening, which produces a pulse of decreased intragastric acidity during the night with a normal acidity in the daytime. High-dose regimens using a new generation of extremely potent histamine H2-receptor antagonists may improve ulcer healing rates at 4 weeks, and may be particularly useful for the management of either severe oesophagitis or intractable duodenal ulceration.

Highly selective vagotomy and duodenal ulcers that fail to respond to H2 receptor antagonists

A study was conducted to see whether patients with duodenal ulcers that failed to heal in response to H2 receptor antagonists had a higher incidence of recurrent ulceration after highly selective vagotomy than patients whose ulcers healed with these drugs. Between 1977 and 1983, 157 patients had a highly selective vagotomy for uncomplicated duodenal ulcer; in 57 patients the ulcer had failed to heal despite treatment with H2 receptor antagonists (refractory group), 19 patients had developed recurrent ulceration while receiving maintenance treatment, 67 patients had remained healed while taking H2 receptor antagonists but suffered frequent relapses when treatment was stopped, and 14 patients had not been given these drugs before operation. The overall incidence of recurrent ulceration was 6% after two years and 11% after five years of follow up. In the refractory group, however, the incidence of recurrent ulceration was 18% at two years and 34% after five years, whereas the incidence of recurrence was only 1.5% at two years and 3% after five years in patients whose ulcers had healed with H2 receptor antagonists. Resistance to H2 receptor antagonists was not related to preoperative basal or peak acid output but was related to cigarette smoking. Factors associated with recurrent ulceration after highly selective vagotomy were basal acid outputs before and after operation, cigarette smoking, and the surgeon who performed the operation. Duodenal ulcers that fail to respond to H2 receptor antagonists represent a more severe ulcer diathesis, for which highly selective vagotomy is less effective.

Stress ulcer prophylaxis and ventilation pneumonia: prevention by antibacterial cytoprotective agents?

The gastric and tracheal flora of 142 consecutive patients receiving stress ulcer prophylaxis were investigated, identifying identical isolates by typing. Furthermore, the growth pattern of normal respiratory bacteria and organisms causing ventilation pneumonia at different pH values and the in vitro effect of sucralfate and bismuth subsalicylate on these bacteria in simulated gastric fluid were studied. The results obtained were as follows: (1) with rising gastric pH bacterial counts in gastric aspirates, especially gram-negatives, increased significantly; (2) in 45 (31.7%) of the patients identical organisms were first isolated in gastric samples and one to two days later in tracheal secretions; (3) ventilation pneumonia was significantly more frequent in patients with high gastric pH; (4) pathogens causing ventilation pneumonia grew well in simulated gastric fluid at higher pH values, unlike normal respiratory organisms; and (5) sucralfate and bismuth subsalicylate showed antibacterial activity against frequent causative organisms of ventilation pneumonia.

Pharmacological response to cimetidine and healing of duodenal ulceration: effects of high-dose cimetidine and combination of cimetidine with pirenzepine

Overnight gastric secretion was studied in 32 patients with acute duodenal ulcers before treatment and whilst taking cimetidine 400 mg b.d. After 6 weeks of treatment with cimetidine 400 mg b.d. 13 patients had healed ulcers, seven patients had healed ulcers but a persistent erosive duodenitis, and 12 patients had persisting ulceration. Inhibition of nocturnal gastric secretion by cimetidine 400 mg b.d. was most profound in patients who healed their ulcers completely; a less profound inhibition of nocturnal gastric secretion was seen in the non-healing and duodenitis groups. In patients with persisting ulcers and poor inhibition of nocturnal gastric secretion by cimetidine, gastric secretion could be suppressed by either cimetidine 400 mg b.d. in combination with pirenzepine 50 mg b.d., or by cimetidine 1600 mg nocte, but suppression of nocturnal gastric secretion was more effective with cimetidine 1600 mg than cimetidine with pirenzepine.

Recent developments in peptic ulcer treatment

Since peptic ulcer disease is a multifactorial disease, the ideal therapeutic approach would be to use different drugs for different ulcers. In the past few years some studies have been published suggesting that subgroups of patients with peptic ulcer might particularly benefit from specific forms of therapy. In the present report the available evidence has been critically reviewed.

Factors which influence the incidence and course of peptic ulcer

The present review concentrates on environmental factors which influence the outcome of peptic ulcer disease by acting from the outside. Endogenous risk factors, such as acid output, pepsin secretion and serum pepsinogen, gastritis and mucosal defense, blood group, and secretor status, are only dealt with when they help to explain the mechanism by which exogenous risk factors affect the upper gastrointestinal mucosa. After outlining the wax and wane of peptic ulcer, it is concluded that these changes resulted from similar temporal patterns of occupational workload in the general population. Cross sectional studies also support the contention of occupational workload being a risk factor in peptic ulcer, explaining several characteristic features of peptic ulcer, such as its sex, race, and social class distribution, increased incidence in immigrant workers, seasonal variation, healing by bed rest, and urban versus rural distribution. Susceptible subjects may react to a rise in occupational workload and acute exposure to stressful life events by increased gastric secretion which, in turn, leads to ulceration and symptoms. Cigarette smoking, intake of aspirin and related drugs, dietary salt, and alcohol abuse represent additional environmental risk factors, which form the etiologic link of the association of peptic ulcer with chronic lung disease, rheumatoid arthritis, hypertensive disease, and liver cirrhosis, respectively.

Misoprostol in the treatment of duodenal ulcer refractory to H2-blocker therapy. A placebo-controlled, multicenter, double-blind, randomized trial

A multicenter, double-blind, randomized study compared 200 micrograms of misoprostol and placebo four times daily for four weeks in the treatment of 225 patients with duodenal ulcer (0.7 cm to 2.0 cm in size) persisting after at least four weeks of adequate, conventional therapy with cimetidine or ranitidine. Misoprostol was significantly superior to placebo in healing duodenal ulcers (achieving a healing rate of 37 percent versus 22 percent in the placebo group [p = 0.02], and in relieving ulcer pain [p = 0.01]). Healing also occurred more frequently with misoprostol than with placebo in patients with subgroups of particularly resistant ulcers. In the treatment of ulcers refractory to at least eight weeks of histamine H2-blocker therapy, misoprostol achieved a healing rate of 42 percent versus 20 percent with placebo. In the treatment of pyloric channel ulcers, 28 percent of patients in the misoprostol group showed healing as compared with 20 percent in the placebo group. Diarrhea was reported by 15.4 percent and 3.4 percent of patients receiving misoprostol and placebo, respectively, and was usually mild and transient. Misoprostol is safe and effective therapy for duodenal ulcers that have not healed during the course of H2-blocker therapy.

Tripotassium dicitrato bismuthate (TDB) versus two different dosages of cimetidine in the treatment of resistant duodenal ulcers

The use of tripotassium dicitrato bismuthate (TDB) has been suggested recently for cimetidine resistant duodenal ulcers. This study compares the efficacy of TDB with two different cimetidine dosages in the treatment of duodenal ulcer patients who failed to respond to an eight week therapy with H2-blockers. Fifty two patients (40 men, 12 women) were randomly allocated to one of the following three oral regimens: (1) TDB 120 mg quid, (2) cimetidine 400 mg tid, (3) cimetidine 400 mg with meals plus 800 mg at bedtime. Endoscopy was carried out after four weeks; if the ulcer had not healed patients continued with the same treatment for a further four week period when they were endoscopically reassessed. After four weeks similar percentages of ulcer healing were registered in the two cimetidine schedules (39% with 1.2 g and 44% with 2 g), whereas TDB resulted in a significantly higher healing rate (82%) compared with cimetidine 1.2 g (p = 0.01) and with cimetidine 2 g (p = 0.025). After eight weeks the cumulative percentages of healing were 65% on cimetidine 1.2 g, 75% on cimetidine 2 g, and 94% on TDB (TDB v cimetidine 1.2 p = 0.042). These results confirm previous data that resistant duodenal ulcers are more responsive to an agent which strengthens the mucosal defences than to antisecretory compounds.

Colloidal bismuth subcitrate and two different dosages of cimetidine in the treatment of resistant duodenal ulcer. Preliminary results

The use of colloidal bismuth subcitrate (CBS) has been recently suggested for cimetidine-resistant duodenal ulcers. We have therefore compared the activity of CBS with that of two different doses of cimetidine in patients whose duodenal ulcers had not healed after 8 weeks of therapy with cimetidine, 1.2 g, or ranitidine, 300 mg/day. Forty-three patients (35 men and 8 women) were randomly allocated to one of the following oral regimens: CBS, 120 mg 4 times a day, or cimetidine (C), 400 mg 3 times a day, or cimetidine, 400 mg at meals plus 800 mg at bedtime, for 4-8 weeks. The interim analysis after 4 weeks of treatment showed similar percentages of healing in the two cimetidine schedules (46.7% with C, 1.2 g, and 42.9% with C, 2 g, respectively); conversely, CBS treatment resulted in a significantly higher healing rate as compared with both C, 1.2 g, and C, 2 g (P less than 0.05). These findings suggest that resistant duodenal ulcers are more responsive to cytoprotective agents than to antisecretory compounds.

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.

Recent experimental and clinical studies on the pharmacology of colloidal bismuth subcitrate

Recent experimental and clinical pharmacological studies on colloidal bismuth subcitrate (CBS) are reviewed. CBS combines with mucus to produce a marked retardation of the movement of hydrogen ions. CBS has potent anti-ulcer and anti-erosive action in various experimental models in animals, and is able to stimulate the generation of gastric mucosal prostaglandins. CBS is thought to be a cytoprotective agent. The type of mucosal cell repair in the vicinity of the ulcer is favourably affected in man. CBS also exhibits anti-pepsin and bile acid-binding properties. Pyloric campylobacter are inhibited in vitro and in vivo. The recent pharmacological findings are discussed in the light of the clinical efficacy of CBS and new indications.