Recurrence of duodenal ulcer and Campylobacter pylori infection after eradication

[Benefits of treatment to eradicate Helicobacter pylori infection in patients with ulcer at a primary care center]

OBJECTIVES

To evaluate the clinical evolution and the use of Primary Care health resources one year after treatment to eradicate Helicobacter pylori (Hp) infection in patients with peptic ulcers and Hp infection.

DESIGN

Retrospective study on the effect of an intervention.

SETTING

Urban, reformed primary care centre.

PATIENTS

102 patients with peptic ulcers and Hp infection.

INTERVENTION

Treatment to eradicate Hp.

MEASUREMENTS AND MAIN RESULTS

a) Total medical attendance; b) attendance for dyspepsia; c) number of ulcerous outbreaks; d) medicines taken to treat dyspepsia. 79.4% of the patients treated were male. Overall mean age was 47.8 +/- 12.4. After the intervention, total attendance (from 8.3 to 6.6, p < 0.001), attendance for dyspepsia (from 3.1 to 1.1, p < 0.00001), and ulcerous outbreaks (from 1.2 to 0.06, p < 0.00001) all dropped sharply. The mean number of medicines prescribed for dyspepsia per patient fell from 1.24 to 0.43, p < 0.0001. Ranitidine prescription fell from 72.7 to 13.8 days (p < 0.001); and omeprazol from 35.1 to 12.2 days (p < 0.03). Estimated total saving per patient was 26,792 pesetas at 1998 values.

CONCLUSIONS

Treatment in primary care to eradicate Hp(+) in ulcerous patients reduced the needs of attendance and the prescription of drugs for ulcers. Just in the first year this supposed a clinical benefit for these patients and important economic savings for the public health service.

Metronidazole containing quadruple therapy for infection with metronidazole resistant Helicobacter pylori: a prospective study

BACKGROUND

Metronidazole remains a key component of H. pylori infection therapy. It has been suggested that despite resistance, metronidazole may be effective when given at high dose with bismuth, tetracycline, and a proton pump inhibitor (quadruple therapy).

AIM

To prospectively evaluate metronidazole quadruple therapy for treatment of metronidazole resistant H. pylori infection in the United States.

METHODS

Patients infected with metronidazole resistant H. pylori were prospectively prescribed 14 days of quadruple therapy consisting of metronidazole 500 mg t.d.s., tetracycline 500 mg q.d.s., two bismuth subsalicylate tablets q.d.s., and omeprazole 20 mg o.d.

RESULTS

A total of 26 patients were entered into the study; 22 for their first treatment and four as re-treatment for failed therapy. Of the 26 patients, 24 were cured (cure rate 92%; 95% CI: 78-99%). Both treatment failures reported full compliance to 14 days of therapy. Side-effects were common and resulted in premature discontinuation of therapy in 31%. Premature discontinuation did not reduce the cure rate.

CONCLUSION

Quadruple metronidazole combination therapy is effective despite the presence of metronidazole resistance and should be considered as either first line therapy or for failures of twice-a-day combination therapies.

Eradication of H. pylori with pantoprazole, clarithromycin, and metronidazole in duodenal ulcer patients: a head-to-head comparison between two regimens of different duration

BACKGROUND

The study was conducted to compare the efficacy and tolerability of two pantoprazole-based triple therapies of different length in the eradication of H. pylori.

METHODS

In this double-blind, multicenter parallel group comparison, H. pylori-positive patients were randomly assigned to either the PCM-7 group (7 days of pantoprazole 40 mg bid, clarithromycin 500 mg bid, metronidazole 500 mg bid) or the PCM-14 m group (modified 14 day therapy of the same regimen with metronidazole only given for 10 days due to labeling reasons). H. pylori status was determined by urease test, histology, culture, and 13C-urea breath test. Treatment outcome was assessed 6 weeks after intake of the last study medication.

RESULTS

The following eradication rates were achieved: for PCM-7 in the MITT population 83% (89/107), in the PP population 84% (81/97); for PCM-14 m in MITT 87% (92/106), in PP 88% (91/104). Ulcer healing rates were: for PCM-7 in MITT population 99% (106/107), in the PP population 99% (96/97); for PCM-14 m in MITT 99% (105/106), in PP 99% (103/104). Gastrointestinal symptoms and gastritis scores decreased in both treatment groups. Equivalence of treatment regimens could be proven for all populations. In total, 64 patients reported adverse events. Five serious adverse events occurred, all unrelated to the study medication.

CONCLUSION

The two pantoprazole-based triple therapies tested in this study are equally effective in H. pylori eradication, ulcer healing and relief from ulcer pain. It is concluded that 7 days of triple therapy are generally sufficient.

Clarithromycin for Helicobacter pylori infection

Helicobacter pylori, a Gram-negative organism that survives in the deep mucus layer and attaches to the gastric surface cells, is estimated to be present in up to one-half of the US population. Chronic H. pylori infection causes chronic gastritis, peptic ulcer diseases and even gastric cancer. Cure of the infection leads to healing of gastric inflammation, prevention of development of peptic ulcer, as well as accelerated healing of peptic ulcers, and prevention of ulcer recurrence. Treatment of H. pylori has undergone substantial evolution over the past decade. Despite the in vitro susceptibility, results from single or even dual drug therapy is typically unsatisfactory and the best therapy is yet to be defined. The best current therapies for H. pylori infection consist of a proton pump inhibitor (PPI) or ranitidine bismuth citrate and two antibiotics (triple therapies), or bismuth, tetracycline, metronidazole and a PPI (quadruple therapy). Clarithromycin is one of the most useful antimicrobials against H. pylori. It is an acid-stable macrolide with a broad spectrum of antibacterial activity, well absorbed with a wide tissue distribution and with mild side effects. Clarithromycin has a low minimum inhibitory concentration (MIC50) for H. pylori and its effect is potentiated by acid inhibition. When combined with a PPI or ranitidine bismuth citrate and amoxicillin or metronidazole, eradication rates of more than 95% can be achieved with susceptible organisms. However, the prevalence of primary and acquired clarithromycin resistance, which is due to mutations within a conserved loop of 23S rRNA of H. pylori, is increasing. In practice, the presence of clarithromycin resistance usually implies reduced success when clarithromycin-containing regimes are used. There is a need for improved therapies for H. pylori where antibiotic resistance is less of a problem.

Is upper gastrointestinal radiography a cost-effective alternative to a Helicobacter pylori "test and treat" strategy for patients with suspected peptic ulcer disease?

OBJECTIVE

Current clinical consensus supports an initial Helicobacter pylori (HP) "test and treat" approach when compared to immediate endoscopy for patients with suspected peptic ulcer disease. Alternative diagnostic approaches that incorporate upper GI radiography (UGI) have not been previously evaluated. We sought to determine the cost effectiveness of UGI compared to a HP test and treat strategy, incorporating recent data addressing the reduced prevalence of HP, lower cost of diagnostic interventions, and reduced attribution of PUD to HP.

METHODS

Using decision analysis, three diagnostic and treatment strategies were evaluated: 1) Test and Treat--initial HP serology, treat patients who test positive with HP eradication and antiulcer therapy; 2) Initial UGI series--treat all patients with documented ulcer disease with HP eradication and antiulcer therapy; and 3) Initial UGI series, HP serology if ulcer present--treat ulcer and HP based on diagnostic test results.

RESULTS

The estimated cost per ulcer cured for each strategy were as follows: test and treat, $3,025; initial UGI, $3,690; and UGI with serology, $3,790. The estimated cost per patient treatment were: test and treat, $498; initial UGI, $610; and UGI with serology, $620. When UGI reimbursement was decreased to less than $50, the UGI strategies yielded a lower cost per patient treated than the test and treat strategy.

CONCLUSION

At the current level of reimbursement, UGI should not be considered a cost-effective alternative to the HP test and treat strategy for the initial evaluation of patients with suspected peptic ulcer disease.

Furazolidone combination therapies for Helicobacter pylori infection in the United States

BACKGROUND

Antibiotic resistance has begun to impair the ability to cure Helicobacter pylori infection.

AIM

To evaluate furazolidone as a component of combination therapies for treatment of H. pylori infection in the United States.

METHODS

Patients with active H. pylori infection received furazolidone combination therapy for 14 days (furazolidone 100 mg and tetracycline 500 mg t.d.s.; omeprazole 20 mg o.d. in the morning and, depending on the pre-treatment antimicrobial susceptibility pattern, 500 mg of metronidazole or clarithromycin t.d.s.).

RESULTS

A total of 27 patients received the metronidazole containing combination (cure rate 100%) and seven received the clarithromycin combination (cure rate 86%). Overall the cure rates for intention-to-treat was 97% (95% CI: 85% to 100%). The single failure took the clarithromycin containing combination for only 2 days (per protocol cure rate = 100%). Side-effects were common and led to discontinuation of therapy in 26% of patients. An attempt to eliminate metronidazole and clarithromycin and use furazolidone, tetracycline, and lansoprazole b.d. produced an unsatisfactory cure rate of 72%.

CONCLUSION

Furazolidone combination therapy appears to be effective. Additional studies with different antimicrobial combinations and duration of therapy are warranted.

Effect of eradication of Helicobacter pylori on the benign gastric ulcer recurrence--a 24 month follow-up study

OBJECTIVES

To evaluate the effect of eradication of Helicobacter pylori (H. pylori) on the recurrence of benign gastric ulcer (BGU) in the patients with BGU.

METHODS

This study was performed for 40 H. pylori-positive BGU patients cured of BGU and H. pylori eradicated, and for 25 H. pylori-positive patients (non-eradicated group) who were not treated with H. pylori eradication regimen or H. pylori was not eradicated. Four different methods--CLOtest, microscopy of Gram stained mucosal smear, culture and histology of modified Giemsa staining--were taken for identifying colonization of H. pylori before treatment, and 4 weeks after completion of triple therapy. For the control group in which triple therapy was not tried, follow-up gastroscopy was done to confirm the healing of the ulcer. To detect BGU recurrence, the gastroscopy was performed at 6, 12, 18, and 24 months after therapy.

RESULTS

In the non-eradicated group, the BGU recurrence rate was 16% within 6 months, 40% within 1 year, 56% within 18 months and 60% within 2 years. The respective recurrence rates in the 40 patients in whom the bacteria had been eradicated were 0%, 7.5%, 10% and 10% (4 patients), respectively. Among the four BGU-recurred patients in whom H. pylori had been eradicated, one patient was found to have BGU recurring with H. pylori positive again in one year, and another two patients had NSAIDs ingestion history.

CONCLUSION

The eradication of H. pylori in patients with BGU reduces the recurrence of BGU. In addition, the major causes of BGU recurrence look like NSAIDs ingestion and reinfection of H. pylori.

Characterization of the respiratory chain of Helicobacter pylori

The respiratory chain of Helicobacter pylori has been investigated. The total insensitivity of activities of NADH dehydrogenase to rotenone and of NADH-cytochrome c reductase to antimycin is indicative of the absence of the classical complex I of the electron transfer chain in this bacterium. NADPH-dependent respiration was significantly stronger than NADH-dependent respiration, indicating that this is a major respiratory electron donor in H. pylori. Fumarate and malonate exhibited a concentration-dependent inhibitory effect on the activity of succinate dehydrogenase. The activity of succinate-cytochrome c reductase was inhibited by antimycin, implying the presence of a classical pathway from complex II to complex III in this bacterium. The presence of NADH-fumarate reductase (FRD) was demonstrated in H. pylori and fumarate could reduce H2O2 production from NADH, indicating fumarate to be an endogenous substrate for accepting electrons from NADH. The activity of NADH-FRD was inhibited by 2-thenoyltrifluoroacetone. A tentative scheme for the electron transfer pathway in H. pylori is proposed, which may be helpful in clarifying the pathogenesis of H. pylori and in opening new lines for chemotherapy against this bacterium.

Three treatment schemes with colloidal bismuth subcitrate (Q-ULCER) in peptic ulcer with Helicobacter pylori

BACKGROUND

Since the discovery, several decades ago, of the infection of the gastric mucosa with Helicobacter pylori and its association with chronic antral gastritis and peptic ulcer, the treatment of ulcer illness has recently been revolutionized.

METHODS

In this study, the clinical effectiveness of three schemes of treatment with colloidal bismuth subcitrate (CBS) were compared. Fifty-three patients suffering from gastroduodenal peptic ulcer with Helicobacter pylori were distributed randomly into three groups. Group I (n = 17) received 240 mg CBS every 12 h for 6 weeks. Group II (n = 17) received 240 mg CBS every 12 h for 6 weeks, pus metronidazole 500 mg every 8 h plus tetracycline 500 mg every 8 h for 10 days. Group III (n = 19) received 240 mg CBS every 12 h for 6 weeks, plus metronidazole 500 mg every 8 h plus amoxicillin 750 mg every 12 h for 10 days. A duodenoscopy investigation with antrum biopsy for a morphologic study and detection of the germ was carried out by means of urease test and histological study (Warthin-Sarry and hematoxylin-eosin).

RESULTS

The three schemes of treatment were effective for ulcerous healing with 70.5%, 82.3%, and 78.2%, respectively, without significant differences. The highest clearing index (52.6%) was obtained in group III.

CONCLUSIONS

With these treatments, the Helicobacter pylori eradication was only observed in 47.3% of the patients studied.

Dual therapy using a double dose of lansoprazole with amoxicillin versus triple therapy using a double dose of lansoprazole, amoxicillin, and clarithromycin to eradicate Helicobacter pylori infection: results of a prospective randomized open study

OBJECTIVES

The eradication of Helicobacter pylori is recommended in duodenal ulcer disease. The aim of this randomized open trial was to evaluate and compare H. pylori eradication and safety after a dual therapy consisting of lansoprazole (30 mg b.i.d.) and amoxicillin (1 g b.i.d.) versus a triple therapy consisting of lansoprazole (30 mg b.i.d.), amoxicillin (1 g b.i.d.), and clarithromycin (500 mg b.i.d.) administered from day 1 to day 14.

METHODS

All patients with an ulcer received lansoprazole (30 mg) from day 15 to day 28. H. pylori status was determined from antral biopsies using histology, culture, and polymerase chain reaction (PCR) upon inclusion and 1-3 months after the end of the treatment.

RESULTS

Of the 50 patients included in the study, five did not adhere to the protocol. H. pylori eradication was obtained in 37.5% of the patients receiving lansoprazole-amoxicillin (n = 9/24) and in 95.2% of the patients receiving lansoprazole-amoxicillin-clarithromycin (n = 20/21, p < 0.0002). Minor side effects appeared in 8.3% of the cases during dual therapy (n = 2/24) and in 52% during triple therapy (n = 13/22, p < 0.001). These side effects consisted mainly of diarrhea and a metallic taste.

CONCLUSION

Concomitant administration of double doses of lansoprazole with amoxicillin and clarithromycin is very efficacious against H. pylori infection compared with dual therapy.

A prospective randomized trial comparing the use of omeprazole-based dual and triple therapy for eradication of Helicobacter pylori

BACKGROUND

Controversy surrounds the optimal composition, dosage, and duration of therapies for eradication of Helicobacter pylori. We prospectively compared omeprazole-based dual and triple therapies in the eradication of H. pylori in a randomized manner.

METHODS

Between June 1995 and March 1997, 1000 consecutive patients with acid-peptic disease associated with H. pylori infection (duodenal ulcer, 388 patients, gastric ulcer, 179 patients; duodenitis, 173 patients; gastritis, 260 patients) were prospectively recruited. They were randomized to either a 2-wk (OA) course of omeprazole 20 mg and amoxicillin 1 g, both given twice daily, or treatment for 1 wk (OCM) with omeprazole 20 mg once daily, clarithromycin 500 mg twice daily, and metronidazole 400 mg twice daily.

RESULTS

The age of these 1000 patients ranged from 16 to 90 yr, with a mean of 54.9 yr. Side effects occurred in 29.6% (95% confidence interval [CI] 25.6-33.8%) and 10.6% (95% CI 8.0-13.6%) of patients taking OCM and OA, respectively (p < 0.0001). Apart from taste disturbance, however, there were no significant differences in the incidences of side effects between the two groups. One patient in the OA group and four patients of the OCM group could not tolerate the medications, and therefore did not complete treatment (p = 0.37). Seven and 13 patients in the OA and OCM groups, respectively, refused a second endoscopy (p = 0.25). The remaining 975 patients underwent a second endoscopy. Positive endoscopic findings were significantly more common in the OA group (51/492; 10.4%; 95% CI 7.8-13.4%) than in the OCM group (25/483; 5.2%; 95% CI 3.4-7.5%) in the per-protocol (PP) analysis (p = 0.004). On intent-to-treat (ITT) analysis, the overall eradication rates in the OA and OCM groups were 73.6% (95% CI 69.5-77.4%) and 92% (95% CI 89.3-94.2%), respectively (p < 0.0001). On PP analysis, the corresponding rates were 74.8% (95% CI 70.7-78.6%) and 95.2% (95% CI 92.9-97.0%), respectively (p < 0.0001).

CONCLUSIONS

A course of omeprazole, clarithromycin, and metronidazole for 1 wk is a safe, well-tolerated, efficacious, and cost-effective treatment for H. pylori infection.

Factors influencing Helicobacter pylori eradication with 2 week combination therapy of lansoprazole and amoxycillin: intragastric distribution of colonization and gastric mucosal atrophy

In Japan, gastric ulcers are often accompanied by marked gastric mucosal atrophy. We evaluated the dual therapy of double-dose lansoprazole and amoxycillin for Helicobacter pylori eradication in Japanese ulcer patients and investigated the effects of intragastric distribution of H. pylori colonization and gastric mucosal atrophy on eradication with this combination therapy. Seventy-six H. pylori-positive ulcer patients received lansoprazole (30 mg) plus amoxycillin (500 mg) twice daily for 2 weeks (LA-60 group), lansoprazole (30 mg once daily) plus amoxycillin (500 mg twice daily) for 2 weeks (LA-30 group) or lansoprazole (30 mg once daily) for 6 or 8 weeks (LPZ group). Infection was evaluated by light microscopy, culture and biopsy urease tests. Helicobacter pylori colonization was classified as localized to the corpus (localized type) or involving the antrum and corpus (whole type). Fundic mucosal atrophy was graded according to endoscopic and histological features. Eradication was achieved in 67.6% in the LA-60 group, 31.6% in the LA-30 group, and 0% in the LPZ group, and moderate or severe histological gastritis was improved in the LA-60 group. Eradication was better in localized-type colonization (92%) than whole-type (56%), and better with fundic mucosal atrophy (84%) than without, but poor in both whole-type colonization and scanty mucosal atrophy (47%). The LA-60 therapy achieves better eradication in Japanese ulcer patients with localized H. pylori colonization and/or gastric mucosal atrophy, which are likely to be important predictors for the successful eradication with dual therapy.

Helicobacter pylori eradication as a surrogate marker for the reduction of duodenal ulcer recurrence

OBJECTIVES

An abundance of data exists documenting the association of H. pylori eradication with the reduction in duodenal ulcer recurrence.

AIM

To evaluate the validity of using H. pylori eradication as a surrogate marker for the reduction in duodenal ulcer recurrence using rigorously controlled studies.

METHODS

Three controlled clinical trials were conducted in patients with uncomplicated, active duodenal ulcers. Patients were treated with various combinations of omeprazole and amoxycillin. Ulcer healing and H. pylori eradication were assessed. For patients whose duodenal ulcer healed, duodenal ulcer recurrence was determined over a 6-month period in patients with H. pylori eradication and those remaining positive for H. pylori at least 4 weeks after treatment. To support the data obtained from these clinical trials, a search of the medical literature was conducted to identify additional human clinical trials in which duodenal ulcer recurrence rates were measured and categorized by H. pylori status at least 1 month post-treatment.

RESULTS

In 11 controlled trials, the overall 6-18-month duodenal ulcer recurrence rate was 54% among patients remaining positive for H. pylori at least 4 weeks after treatment compared to 6% among patients with H. pylori eradication following treatment. This finding was corroborated by the uncontrolled trials, in which the duodenal ulcer recurrence rate was 64% among patients found to be H. pylori-positive and 6% for patients found to be H. pylori-negative at least 4 weeks after treatment. A time course of duodenal ulcer recurrence rates using pooled data from both controlled and uncontrolled studies demonstrated that duodenal ulcer recurrence rates for H. pylori-negative patients persisted for up to 4 years following treatment. Duodenal ulcer recurrence rates for H. pylori-positive patients increased for the first year, then levelled off. A comparison of the duodenal ulcer recurrence rates for different treatment regimens revealed that eradication regimens based on omeprazole plus antibiotics and bismuth plus antibiotics exhibited similar duodenal ulcer recurrence rates for H. pylori-positive and -negative patients.

CONCLUSION

Regardless of treatment regimens, H. pylori eradication produced a consistent and significant reduction in duodenal ulcer recurrence. Therefore H. pylori eradication, 4 weeks post-therapy, can be used as a surrogate marker for reduced duodenal ulcer recurrence in investigational clinical trials.

Ranitidine bismuth citrate in the treatment of Helicobacter pylori infection and duodenal ulcer

OBJECTIVE

To review the clinical pharmacology of ranitidine bismuth citrate in the treatment of Helicobacter pylori (HP) infection and duodenal ulcer.

DATA SOURCES

A MEDLINE search of the English-language literature from 1992 to January 1997 was conducting using the key terms Tritec, ranitidine, and bismuth. References of articles pertaining to treatment of duodenal ulcer or HP were extensively searched for relevant sources.

DATA EXTRACTION

All articles pertaining to ranitidine bismuth citrate were considered for inclusion, with emphasis placed on randomized, double-blind trials. Priority was placed on data pertaining to regimens that are currently approved by the Food and Drug Administration for the treatment of duodenal ulcer in conjunction with HP.

DATA SYNTHESIS

Each tablet of ranitidine bismuth citrate 400 mg contains 162 mg of ranitidine base, 128 mg of trivalent bismuth, and 110 mg of citrate. It uses the acid-suppressive actions of ranitidine and the antimicrobial and mucosal protective effects of bismuth to eradicate HP. Ranitidine bismuth citrate in conjunction with clarithromycin represents one of four treatment regimens currently approved in the US for duodenal ulcer associated with HP infection. In four double-blind, randomized trials, this agent has achieved HP eradication rates of 73-94% and duodenal ulcer healing rates of 73-89%. It is given twice daily for 28 days, and is associated with very low rates of adverse effects.

CONCLUSIONS

Relative to some therapeutic alternatives, ranitidine bismuth citrate plus clarithromycin may be simpler to take and have less adverse effects, but may be more expensive. Compared with omeprazole plus clarithromycin, it is less expensive, may have lower ulcer healing rates, but may be more effective in eradicating HP. The role of ranitidine bismuth citrate will continue to evolve as more patients are treated, and other regimens continue to be tested for duodenal ulcer healing and HP eradication.

Effect of metronidazole resistance on bacterial eradication of Helicobacter pylori in infected children

A prospective study was performed with 23 Helicobacter pylori-infected children (mean age, 9.5 +/- 4.4 years) with clinical symptoms of gastritis and positive results of culture and histologic examination of gastric biopsy specimens to evaluate the influence of antibiotic resistance on eradication. Positive children were treated for 4 weeks with lansoprazole and for 2 weeks with either amoxicillin-metronidazole or spiramycin (a macrolide)-metronidazole. At endoscopy 1 month after the discontinuation of therapy, the eradication rate and improvement of histologically related gastritis were significantly dependent on the susceptibility or the resistance of the infecting organism to metronidazole (83 versus 17% and 88 versus 16.6%, respectively). Pretreatment determination of the susceptibility is appropriate in any anti-H, pylori regimen, including one with metronidazole.

Triple versus dual therapy for eradicating Helicobacter pylori and preventing ulcer recurrence: a randomized, double-blind, multicenter study of lansoprazole, clarithromycin, and/or amoxicillin in different dosing regimens

OBJECTIVE

The efficacy and safety of dual and triple therapies with a proton pump inhibitor and antibiotic(s) for therapy of Helicobacter pylori-associated duodenal ulcer disease have been compared using results from independent studies using different methods and regimens, making interpretation difficult. In a large, double-blind, multicenter study conducted in the United States, we compared a triple therapy regimen with four dual therapy and one monotherapy regimens in the eradication of H. pylori and the prevention of ulcer recurrence.

METHODS

Patients with active duodenal ulcer disease or history of duodenal ulcer disease within the past year and H. pylori infection were randomized to receive one of six 14-day treatment regimens: lansoprazole 30 mg, clarithromycin 500 mg, and amoxicillin 1 gm b.i.d.; lansoprazole 30 mg b.id. and either clarithromycin 500 mg b.i.d. or t.i.d.; lansoprazole 30 mg b.i.d. or t.i.d. with amoxicillin 1 gm t.i.d.; or lansoprazole 30 mg t.i.d. alone. No additional acid suppression therapy followed eradication therapy. Primary efficacy endpoints were eradication of H. pylori and ulcer recurrence.

RESULTS

Of 396 patients enrolled in the study, 352 met the entry criteria for duodenal ulcer status and H. pylori positivity. At 4-6 wk after the end of therapy, H. pylori was eradicated from 94% (44 of 47) of patients receiving lansoprazole, clarithromycin, and amoxicillin triple therapy, 77% (39 of 51) of those receiving lansoprazole t.i.d./amoxicillin t.i.d., 75% (36 of 48) of those receiving lansoprazole b.i.d./clarithromycin t.i.d., 57% (28 of 49) of those receiving lansoprazole b.i.d./clarithromycin b.i.d., 53% (26 of 49) of those receiving lansoprazole b.i.d./amoxicillin t.i.d., and 2% (1 of 53) of those receiving lansoprazole monotherapy (p < or = 0.05, triple therapy vs each dual therapy and each dual therapy vs monotherapy). Of those patients who were documented as free of ulcer at 4-6 wk after treatment, ulcers recurred within 6 months in 7% of patients receiving triple therapy, as compared with 13-23% of patients receiving dual therapy, and 69% of patients receiving lansoprazole monotherapy. Patients who were H. pylori negative at 4-6 wk after treatment were less likely to have an ulcer recurrence than were patients who were H. pylori positive (11% [10 of 95] vs 47% [20 of 43], respectively, across treatment groups). For triple therapy and dual therapy, a similar proportion of patients reported a drug-related adverse event (23% vs 17-33%, respectively).

CONCLUSIONS

In patients with active or a recent history of duodenal ulcer, a 14-day course of lansoprazole-based triple therapy without additional acid suppression therapy is highly effective in the eradication of H. pylori and in preventing ulcer recurrence. Among the dual therapies, higher eradication rates occurred when lansoprazole (with amoxicillin) or clarithromycin (with lansoprazole) was administered t.i.d. vs b.i.d., but the rates were still significantly lower than with lansoprazole triple therapy with all three drugs administered b.i.d.

An analysis of seven different methods to diagnose Helicobacter pylori infections

BACKGROUND

It has been debated which diagnostic test should be preferred for the diagnosis of Helicobacter pylori in patients with gastroduodenal diseases.

METHODS

The H. pylori infection was diagnosed prospectively in 97 untreated patients. H. pylori was diagnosed by means of tests based on five different principles: 1) culture, 2) microscopy (HLO), 3) urease activity (urea breath test (UBT) and urease test on biopsy specimens (CLO test)), 4) DNA detection (polymerase chain reaction (PCR)), and 5) IgG antibody detection (enzyme-linked immunosorbent assay (EIA) and Western blotting (WB)).

RESULTS

This study showed that two positive tests out of five tests, based on different principles, were most reliable for predicting the H. pylori infection. Most tests had specificities and predictive values for a negative result greater than 90%. The most important difference between the tests was the sensitivity and the predictive value for a positive result (PPV). WB, HLO, UBT, and PCR had sensitivities and PPV greater than 75%.

CONCLUSIONS

The non-invasive tests UBT and WB are reliable, both alone and in combination, and they are recommended for the pre-endoscopic diagnosis of H. pylori. WB is recommended as a confirmative test for antibody detection by EIA. When patients have an upper endoscopy, we recommend taking biopsy specimens for culture and histology because of the additional information obtained about susceptibility, virulence determinants, and morphology, including the degree of inflammation.

Appearance of a metronidazole-resistant Helicobacter pylori strain in an infected-ICR-mouse model and difference in eradication of metronidazole-resistant and -sensitive strains

We tested whether antibiotic-resistant strains appeared in vivo after the failure of treatment using the Helicobacter pylori-infected euthymic mouse model. The numbers of colonies isolated from 56 ICR mice 2 weeks after 4 days of treatment with metronidazole (3.2, 10, or 32 mg/kg of body weight) or amoxicillin (1, 3.2 or 10 mg/kg), with treatment started 4 days after H. pylori CPY2052 inoculation, were counted, and the isolated strains were tested for their sensitivities to two antibiotics to rule out the presence of antibiotic-resistant strains. One metronidazole-resistant strain was detected in a mouse treated with 10 mg of metronidazole per kg, and the MIC of metronidazole for this strain was 25 microg/ml, compared to a MIC of 1.56 microg/ml for the original strain. However, no resistant strain was detected in the amoxicillin treatment group. After the examination described above, mice challenged with a metronidazole-resistant or -sensitive strain isolated from the stomach of a mouse were treated with metronidazole or amoxicillin. The metronidazole-resistant strain was more difficult to eradicate in vivo than the sensitive strain after treatment with metronidazole but not after treatment with amoxicillin. Thus, a metronidazole-resistant H. pylori strain was selected by insufficient treatment, but no resistant strain was selected with amoxicillin. Eradication of a metronidazole-resistant H. pylori strain in vivo required a higher dosage than eradication of a metronidazole-sensitive H. pylori strain. These results may explain one of the reasons for H. pylori treatment failure.

Successful low-dose amoxycillin, metronidazole and omeprazole combination therapy in a population with a high frequency of metronidazole-resistant Helicobacter pylori

AIM

Effective anti-Helicobacter pylori therapies with few side-effects are needed. We studied the effectiveness of a low-dose combination of metronidazole, amoxycillin and omeprazole for treatment of ulcer patients in Seoul, Korea.

METHODS

Patients with gastric or duodenal ulcer received metronidazole (125 mg b.d.), amoxycillin (500 mg b.d.) and omeprazole (20 mg at bedtime) for 2 weeks. Endoscopic examinations were performed before treatment and at least 6 weeks after completion of antimicrobial therapy. H. pylori status was confirmed by histological examination of two gastric biopsies using the Genta stain.

RESULTS

Seventy-nine patients (64 men, 15 women, mean age 46 years) with peptic ulcer were enrolled. H. pylori infection was cured in 56 (71%) 95% CI: 60-81%). The cure rate in non-smokers was significantly higher than in smokers (88% vs. 65%, P = 0.035). Twelve pre-treatment isolates were available and metronidazole resistance was noted in all; H. pylori infection was cured in 10. Thirty-six patients cured of H. pylori have been followed for 1 year (mean of 361 days) and 2 cases became reinfected (5.5%, 95% CI: 1-18%).

CONCLUSIONS

The low-dose combination of metronidazole, amoxycillin and omeprazole was effective even the in face of metronidazole resistance. Recurrence of H. pylori infection is infrequent even in countries with a high prevalence of H. pylori infection.

Time of Helicobacter pylori eradication assessment following treatment

BACKGROUND

The most appropriate time to assess accurately Helicobacter pylori eradication following treatment has been debated, with recommendations ranging from 1 to 3 months. The purpose of this study was to validate the assessment of H. pylori eradication 1 month following treatment.

MATERIALS AND METHODS

Three randomized, double-blind, active-controlled clinical trials were conducted in patients with endoscopically verified, active duodenal ulcers and H. pylori infection. Patients were treated with various treatment regimens of omeprazole plus amoxicillin. Ulcer healing, H. pylori eradication, and ulcer relapse were examined. Patients underwent repeat endoscopy and biopsy at 1 and 6 months following treatment (or sooner if symptoms returned) to determine the recurrence of ulcers and H. pylori status. To determine the accuracy of measuring H. pylori eradication at 1 month posttreatment, we compared the H. pylori status at 1 month and 6 months following treatment.

RESULTS

In a combination of treatment groups and studies, a total of 384 evaluable patients represented data at both time points and were included in the analysis. Of those eradicated at 1 month posttreatment, 94% (141 of 150) remained eradicated at 6 months posttreatment. The proportion of patients with H. pylori eradicated at 1 month posttreatment did not differ significantly from that at 6 months posttreatment for each study. The overall efficiency of the two tests (agreement between tests) was 93% (359 of 384). Agreement between the 1-month and 6-month posttreatment H. pylori assessment was apparent, regardless of the treatment used.

CONCLUSION

H. pylori eradication measured 1 month following cessation of treatment accurately reflects successful treatment of the infection.

Lansoprazole and amoxycillin: observations on the treatment of Helicobacter pylori infection

Symptomatic patients (n = 101) with Helicobacter pylori infection were enrolled into a double-blind, double-dummy study to assess the efficacy of lansoprazole plus amoxycillin in the treatment of H. pylori infection. Patients were randomized to either lansoprazole 30 mg once daily (days 0-28) together with placebo (matched to amoxycillin) three times a day (days 0-14) followed by either placebo or amoxycillin 500 mg three times daily (days 15-28). Biopsy specimens for culture and histology were collected on days 0 and 56 or upon symptomatic relapse. Blood for serology was collected at days 0, 56 and 168. A [14C]-urea breath test was performed on day 168. Eighty-one (80.2%) patients completed the 56 day assessment. Of patients treated with lansoprazole plus amoxycillin, 35.1% (13/37) were cured of infection as assessed at day 56 (26.5% on an intention-to-treat basis), compared with 4.8% (2/42) of the placebo group (4% on an intention-to-treat basis). Recrudescence/re-infection occurred in one patient upon re-evaluation at day 168. Analysis of prognostic factors indicated that smoking and alcohol intake had little impact on the treatment outcome. Inflammation (both acute and chronic) improved in patients treated with lansoprazole plus amoxycillin. The relatively low efficacy of the treatment may relate to a single daily dose of lansoprazole (30 mg) being prescribed, treatment with amoxycillin being commenced 2 weeks after the initiation of lansoprazole or accurate assessment of treatment efficacy (both antral and body biopsy specimens taken).

Experimental Helicobacter pylori infection in association with other bacteria

We performed surgical treatment on normal ddY mice before Helicobacter pylori inoculation. The treatment was expected to obstruct bacterial flow out of the stomach and increase the chance of bacterial attachment to the gastric epithelium in mice. The bacterial challenge induced inflammation in the stomach. H. pylori was recovered from the stomach throughout the observation period. Lactobacilli and streptococci tended to relate to the increase in number of H. pylori recovered. Pretreatment with atropine was considered to confuse the gastric flora and affect the number of H. pylori recovered. These results suggested that a certain amount of time is necessary for H. pylori to contact with the gastric epithelium and that the composition of flora is important for the establishment of H. pylori infection.

Double-blind, multicenter evaluation of lansoprazole and amoxicillin dual therapy for the cure of Helicobacter pylori infection

BACKGROUND

Treatment with amoxicillin plus omeprazole results in disappointing cure rates of Helicobacter pylori infection. The minimal inhibitory concentration of lansoprazole for H. pylori in vitro is lower than that for omeprazole, prompting interest in treatment with amoxicillin plus lansoprazole.

MATERIALS AND METHODS

H. pylori-infected patients with endoscopically documented duodenal ulcer either currently or within the past year were randomized to 14 days of (1) lansoprazole, 30 mg bid, plus amoxicillin, 1 gm tid; (2) lansoprazole, 30 mg tid, plus amoxicillin, 1 gm tid; (3) lansoprazole, 30 mg tid alone; or (4) amoxicillin, 1 gm tid alone. Endoscopy was done at enrollment and at 4 to 6 weeks after completion of treatment or for recurrent symptoms. H. pylori status was assessed by culture and histology. Ulcer prevalence was evaluated at follow-up endoscopy.

RESULTS

Two hundred sixty-two patients met enrollment criteria and were treated. By per-protocol analysis, H. pylori infection was cured in 57% of those treated with lansoprazole twice daily plus amoxicillin and in 67% of those treated with lansoprazole three times daily plus amoxicillin, compared with 0% treated with lansoprazole alone or amoxicillin alone (p < .001 for dual therapy versus either monotherapy). Amoxicillin resistance was not observed. At follow-up endoscopy, ulcer prevalence was 17% in patients treated with lansoprazole twice daily plus amoxicillin, 23% in those treated with lansoprazole three times daily plus amoxicillin, 33% in those treated with lansoprazole alone, and 35% in those treated with amoxicillin alone (p = .024; lansoprazole twice daily plus amoxicillin versus amoxicillin alone).

CONCLUSIONS

Treatment with amoxicillin plus lansoprazole, 30 mg tid, led to cure of H. pylori infection in 67% of patients with active or recently healed duodenal ulcer.

Double-blind, multicenter, placebo-controlled evaluation of clarithromycin and omeprazole for Helicobacter pylori-associated duodenal ulcer

BACKGROUND

Eradication of Helicobacter pylori leads to faster ulcer healing and a significant decrease in ulcer recurrence. Clarithromycin is the most effective monotherapy for eradicating H. pylori from the gastric mucosa, and omeprazole frequently is used for the treatment of duodenal ulcer disease, prompting the interest to investigate rigorously the combination of clarithromycin and omeprazole for eradicating H. pylori.

MATERIALS AND METHODS

The aim of this double-blind, randomized, multicenter (n = 30), multinational (n = 10) study was to compare clarithromycin and omeprazole with omeprazole monotherapy for the eradication of H. pylori from the gastric mucosa, endoscopic healing, and reduction of symptoms and ulcer recurrence in patients with active duodenal ulcer. Patients with active duodenal ulcer associated with H. pylori infection were randomized to receive omeprazole, 40 mg every morning for 14 days, with either clarithromycin, 500 mg, or placebo three times daily, which was followed by omeprazole, 20 mg every morning for 14 days. Patients underwent endoscopy before enrolling in the study, immediately after finishing treatment, and at 4- to 6-week and 6-month follow-up evaluations or at the recurrence of symptoms.

RESULTS

Two hundred and eight patients with active duodenal ulcer associated with confirmed H. pylori infection were randomized to treatment with either clarithromycin and omeprazole (n = 102) or omeprazole and placebo (n = 106). Four to six weeks after treatment was completed, H. pylori was eradicated in 74% (95% confidence interval, 63.0%-82.4%) of patients receiving clarithromycin and omeprazole, compared with 1% (0.0%-6.2%) of patients receiving omeprazole monotherapy (p < .001). Clarithromycin resistance developed in eight patients treated with clarithromycin and omeprazole and in none given omeprazole and placebo. Ulcers, which were healed following treatment in more than 95% of study patients, recurred by the 6-month follow-up visit in 10% (5%-19%) of dual therapy recipients, compared with 50% (39%-61%) of those who took omeprazole alone (p < .001).

CONCLUSION

Clarithromycin and omeprazole dual therapy is simple and well-tolerated and leads to consistently high eradication rates for patients with duodenal ulcer associated with H. pylori infection.

A risk-benefit assessment of drugs used in the eradication of Helicobacter pylori infection

Helicobacter pylori is the cause of chronic active gastritis and predisposes to peptic ulcer disease (PUD). Furthermore, H. pylori is linked to the pathogenesis of gastric lymphoma and gastric cancer. However, treatment of this infection has proven difficult. In the last decade, many antimicrobial compounds have been studied extensively as monotherapy as well as in combination with bismuth or acid-suppressive drugs. The individual drugs and the most important eradication regimens are discussed with special regard to their risks. In the past, highly complex multidrug regimens, fear of adverse effects and frequent eradication failures have hampered the broad acceptance of H. pylori-eradication therapies. Recently, new 1-week, low-dose combination regimens of 2 antibacterials with a proton pump inhibitor have consistently achieved eradication rates of 90% and more with an acceptably low rate of adverse effects. One week's standard triple therapy [tripotassium dicitrato bismuthate (or bismuth salicylate plus metronidazole plus tetracycline or amoxicillin) has been shown to be highly effective and tolerated better in combination with a proton pump inhibitor. This regimen is, however, more complex and has more adverse effects. Therefore, it is not recommended as first-line therapy. Equipped with these therapies physicians can now be strongly encouraged to use H. pylori eradication as the therapy of choice for patients with PUD and even extend this treatment to other H. pylori-associated disease conditions.

Refinement of, and new applications for, Helicobacter pylori colonization in pig gastric biopsy specimens cultured in vitro

BACKGROUND

As we have previously reported, pig gastric biopsy specimens cultured in vitro are a highly useful model for studies of Helicobacter pylori growth and adhesion. The aim of this study was to further refine the model in terms of mucosal specificity, culture time, bacterial adhesion, and drug delivery.

METHODS

H. pylori-inoculated antral and corporeal pig gastric specimens were cultured for up to 96 h. Biopsy viability, bacterial growth, and adhesion were determined every 24 h. Bismuth subcitrate and omeprazole were added to the top of the specimens via a bio-adhesive gel.

RESULTS

Corporeal and antral specimens could be cultured for 72 h and 96 h, respectively, without affecting the viability. In parallel experiments from the same pig the percentage adhesion and total number of adhering H. pylori was higher in corporeal than in antral specimens at 72 h (28% and 4 x 10(5) versus 15% and 4 x 10(4), respectively). Removal of loosely attached H. pylori by rinsing at 24 h doubled the percentage H. pylori adhered during the subsequent 48 h. Bismuth subcitrate had a dose-dependent inhibitory effect on H. pylori; when added to the mucosal side, omeprazole had no effect.

CONCLUSION

The pig in vitro biopsy model can be used for detailed H. pylori adhesion studies and for the screening of drugs added to the mucosal or serosal side.

Protective immunization against Helicobacter stimulates long-term immunity

Immunization with an oral vaccine composed of whole cell sonicates of Helicobacter felis plus cholera toxin (CT) can protect mice from H. felis challenge. The aim of this study was to determine whether this protective immunity was long-lived. Mice were given the vaccine then left for up to 15 months before challenge. After 15 months, all mice were still protected from H. felis infection, indicating that oral immunization using bacterial antigens plus CT can stimulate long-term local immunological memory.

Helicobacter colonization of biopsy specimens cultured in vitro is dependent on both mucosal type and bacterial strain

BACKGROUND

Colonization by Helicobacter pylori is strictly tissue-specific. We have previously reported on an in vitro adhesion model for pig and human gastric mucosa, in which biopsy specimens were successfully infected and cultured for 72h. The aim of this study was to compare H. pylori colonization of different mucosae and by different Helicobacter strains.

METHODS

Specimens from pig, rabbit, and rat antrum, pig urinary bladder, and pig duodenum were inoculated with two H. pylori strains and one H. mustelae strain. Four additional strains, including one mutant lacking flagella, were compared on pig antral specimens.

RESULTS

The viability of all mucosae was comparable at 48h of culture. The percentage adhering bacteria increased with time in all mucosae, reaching 17%, 11%, and 2% in pig, rabbit and rat antral mucosa, 11% in pig bladder, and 3% in duodenum at 48h. The type of H. pylori strain was a strong determinant for adhesion in pig antrum. Strain SVA40 had the highest adhesion; the mutant lacking flagella colonized very poorly. H. mustelae adhered to all types of mucosae in a more unspecific manner.

CONCLUSIONS

On the basis of tissue viability, bacterial colonization, and adhesion, pig antral mucosa is clearly superior. H. pylori strains differ in their ability to adhere to and colonize cultured mucosa.

The Helicobacter felis mouse model in assessing anti-Helicobacter therapies and gastric mucosal prostaglandin E2 levels

BACKGROUND

The aims of the present study were to assess the usefulness of the Helicobacter felis mouse model in the evaluation of antimicrobial therapies and the effect of Helicobacter infection on gastric mucosal prostaglandin E2 release.

METHODS

Barrier-maintained BALB/c mice were infected with H. felis and treated with different antibacterial therapies. H. felis status was determined by bacterial culture, urease test, and bacterial and histologic stainings. Release of prostaglandin E2 from the gastric mucosa was measured by radioimmunoassay.

RESULTS

All triple-treated mice were cleared of bacteria both 24 h and 1 month after treatment. However, tinidazole alone also resulted in 100% eradication. Monotherapies with erythromycin acistrate, tetracycline, colloidal bismuth subcitrate, and nitecapone failed to eradicate the bacteria. The release of gastric prostaglandin E2 was doubled in the infected mice (554 +/- 39, mean +/- SE) compared with the noninfected mice (270 +/- 35) (p < 0.01).

CONCLUSIONS

The H. felis mouse model proved satisfactory for assessing both anti-Helicobacter therapies and the prostaglandin E2 release. The reliability of this method was improved when several methods to assess the H. felis status were used in parallel.

Synthesis, gastroprotective, antisecretory and anti-Helicobacter effect of N-[3-(3-(1-piperidinylmethyl) phenoxy)propyl]-hydroxyacetamide 2-hydroxypropane-1,2,3-tricarboxylate bismuth (3+) complex (MX1)-MX1

MX1 (N-[3-(3-(1-piperidinylmethyl)phenoxy)propyl]-hydroxyacetamide+ ++ 2-hydroxypropane-1,2,3-tricarboxylate bismuth (3+) complex) is a novel salt of the active metabolite of H2-antagonist roxatidine with a complex of bismuth with citric acid. In a model of ethanol-induced ulcers in male Wistar rats, both roxatidine and the bismuth salt reduced the number and the total length of lesions. Comparison of roxatidine and MX1 at equimolar doses of 160 mumol kg-1 showed a more potent cytoprotective effect of MX1. The potency of anti-secretory and antiacidic effects of MX1 was more than twice that of roxatidine on histamine-stimulated secretion in female Wistar pylorus-ligated rats. Microbiological tests with the reference bismuth preparation De-Nol showed prominent anti-Helicobacter properties of MX1 in-vitro. Both test compounds had similar range of MICs to Helicobacter pylori, from 4 to 64 microgram bismuth mL-1. The cytoprotective, antisecretory, anti-acidic and anti-Helicobacter properties of the new agent MX1 warrant further more extensive pharmacological and clinical trials.

The treatment of Helicobacter pylori infection in the management of peptic ulcer disease

Antimicrobial therapy against H. pylori is indicated for all patients with documented peptic ulcer disease who have evidence of the infection. The regimen of first choice, selected on the basis of available studies, is triple therapy with bismuth, metronidazole, and tetracycline (Table 1). For patients who are known to have taken metronidazole previously, clarithromycin may be substituted for metronidazole. For patients with active, symptomatic peptic ulcers we also recommend an antisecretory drug to promote healing and relieve symptoms. Second-choice regimens consist of combinations of two antimicrobial drugs--metronidazole, amoxicillin, or clarithromycin--with an antisecretory agent, preferably an H+/K+-ATPase antagonist such as omeprazole. The combination of a single antimicrobial drug (especially amoxicillin) with omeprazole is less efficacious and cannot be recommended. Regardless of the antimicrobial regimen used, successful eradication of H. pylori infection markedly reduces the risk of recurrent peptic ulcers. If this therapeutic approach is taken with all patients with peptic ulcers, the recurrence of ulcers should become a rarity in medical practice.

Helicobacter pylori eradication in a clinical setting: success rates and the effect on the quality of life in peptic ulcer

BACKGROUND

Helicobacter pylori eradication for peptic ulcer has been widely taken up. Evidence for the efficacy of different regimens is often derived from small series in clinical trials but there is little reporting of everyday practice with unselected patients. Freedom from ulcer relapse has been demonstrated, but not whether this equates with clinical success.

METHODS

We report on a series of 706 patients with H. pylori infection who, between January 1991 and April 1995, received eradication therapy followed by assessment of H. pylori status. Two-hundred and seven of these patients were followed-up by postal questionnaire, validated by parallel questionnaires to their general practitioners, covering clinical outcome measures.

RESULTS

The overall eradication rate was 81.7%, and a 1-week course of omeprazole plus two antibiotics was significantly better than a 2-week course of standard triple therapy (85.0% vs. 78.0%, P < 0.05). Amongst 21 first-time failures, a 7-day course of a clarithromycin-containing triple therapy succeeded in 18. The questionnaire replies indicate that, following successful H. pylori eradication, ulcer patients are less likely to consult with ulcer symptoms (P < 0.0005), take medication (P < 0.0005), require further prescription (P < 0.0005), or lose work-time because of their ulcer (P < 0.005). They are more likely to have a subjective sense of ulcer cure (P < 0.0005).

CONCLUSIONS

In addition to clear cost savings, social benefits are now demonstrated when H. pylori is eradicated. A well-tolerated 1 week regimen is genuinely effective in everyday practice.

Helicobacter pylori in duodenal and gastric ulcer disease

The decision to treat a patient should in general always be based on potential risk and advantage. Widespread and uncontrolled use of all kinds of anti-H. pylori regimens may promote development of antimicrobial resistant strains. In particular, antimicrobial monotherapy is associated with failure to eradicate H. pylori and induction of resistant strains. Polychemotherapy is much more effective and has a lower risk for development of antimicrobial resistant H. pylori strains but carries the risk of significant drug-related side effects. If the prescribed anti-H. pylori regimen is not effective in at least 80%, or if the patient is not compliant, this type of therapy should not be considered. Also if reinfection is to be expected, the risk may outweigh potential benefits (Graham, 1993). Guidelines published in 1990 by an international working party during the World Congress of Gastroenterology recommended H. pylori eradication only in patients where duodenal ulcer was a serious management problem requiring lifelong maintenance therapy, and in whom complications (bleeding, perforation) had occurred or surgery was considered (Tytgat et al, 1990). Recently less stringent guidelines were recommended. A National Institutes of Health (NIH) Consensus Development Conference has recommended that all patients with gastric or duodenal ulcer who are H. pylori infected should be treated with antimicrobials including patients presenting with an ulcer for the first time. In addition, patients on maintenance antisecretory medication should also be contacted and treated for H. pylori infection (Anonymous, 1994). The ulcer relapse rate during prolonged follow-up after H. pylori eradication is very low. Despite this, it is advised that antisecretory medication is continued after successful H. pylori eradication in patients with previous ulcer complications. In all other patients maintenance antisecretory medication can be stopped after successful eradication. It is not known whether H. pylori eradication lowers the risk of NSAID-induced ulceration or whether the risk of ulcer complications is reduced.

Eradication of Helicobacter pylori and prevention of recurrence of duodenal ulcer: a randomized, double-blind, multi-centre trial of omeprazole with or without clarithromycin

BACKGROUND

Antimicrobial treatment for Helicobacter pylori eradication is currently recommended for all patients with duodenal ulcer disease, but consensus on the best treatment is lacking.

METHODS

Patients with active duodenal ulcer and H. pylori were enrolled in a double-blind, randomized, placebo-controlled multi-centre study. Patients received omeprazole 40 mg daily for 28 days and either clarithromycin 500 mg t.d.s. or placebo t.d.s. for the first 14 days. Patients underwent endoscopy before starting treatment, at 2 weeks, immediately after stopping treatment if unhealed at 2 weeks, and at 1, 6 and 12 months after the end of treatment, or at the recurrence of symptoms. Eradication of H. pylori, duodenal ulcer healing and ulcer recurrence were measured.

RESULTS

One-hundred and fifty-four patients were recruited and randomized to omeprazole plus clarithromycin (n = 74) or to omeprazole plus placebo (n = 80). One month after treatment, H. pylori was eradicated in 57 of 69 (83%; 95% CI: 72-91%) patients receiving omeprazole plus clarithromycin, compared with 1 of 75 (1%; 95% CI: 0-7%) receiving omeprazole alone (P < 0.001). In patients receiving omeprazole plus clarithromycin the ulcer healed at 2 weeks in 83% (95% CI: 71-91%) and at 4 weeks in 100% (95% CI: 95-100%), compared with 77% (95% CI: 66-86%) and 97% (95% CI: 91-100%) in those given omeprazole plus placebo (N.S.). Ulcers recurred at 12 months in 6% (95% CI: 1-16%) of patients given omeprazole plus clarithromycin, compared with 76% (95% CI: 63-86%) of patients given omeprazole plus placebo (P < 0.001). The incidence of side-effects was similar in both treatment groups (38% with clarithromycin dual therapy and 29% with omeprazole plus placebo; P = 0.304). Ninety per cent of patients took at least 90% of their prescribed medication.

CONCLUSIONS

Omeprazole plus clarithromycin dual therapy eradicated H. pylori in 83% of patients with duodenal ulcer and significantly decreased 12-month recurrence from 76% to 6%.

Cluster analysis of Helicobacter pylori genomic DNA fingerprints suggests gastroduodenal disease-specific associations

BACKGROUND

Helicobacter pylori infection is now accepted as the most common cause of chronic active gastritis and peptic ulcer disease. The etiologies of many infectious diseases have been attributed to specific or clonal strains of bacterial pathogens. Polymerase chain reaction (PCR) amplification of DNA between repetitive DNA sequences, REP elements (REP-PCR), has been utilized to generate DNA fingerprints to examine similarity among strains within a bacterial species.

METHODS

Genomic DNA from H. pylori isolates obtained from 70 individuals (39 duodenal ulcers and 31 simple gastritis) was PCR-amplified using consensus probes to repetitive DNA elements. The H. pylori DNA fingerprints were analyzed for similarity and correlated with disease presentation using the NTSYS-pc computer program.

RESULTS

Each H. pylori strain had a distinct DNA fingerprint except for two pairs. Single-colony DNA fingerprints of H. pylori from the same patient were identical, suggesting that each patient harbors a single strain. Computer-assisted cluster analysis of the REP-PCR DNA fingerprints showed two large clusters of isolates, one associated with simple gastritis and the other with duodenal ulcer disease.

CONCLUSIONS

Cluster analysis of REP-PCR DNA fingerprints of H. pylori strains suggests that duodenal ulcer isolates, as a group, are more similar to one another and different from gastritis isolates. These results suggest that disease-specific strains may exist.

Helicobacter pylori reinfection with identical organisms: transmission by the patients' spouses

Reinfection with Helicobacter pylori after eradication is responsible for the recurrence of duodenal ulcer disease. The mode of transmission has not yet been established. In this study, 18 patients with chronic duodenal ulcers in whom H pylori had been eradicated with amoxicillin and metronidazole were entered into a prospective follow up study. Control endoscopies were performed 4, 8, 14, 27, and 43 months after starting treatment and the results of direct tests were compared with the kinetics of H pylori specific IgG titres. After eradication there was a noticeable and consistent fall in anti-H pylori IgG, while reinfections were characterised by a significant increase in specific titres. Reinfection was detected in two patients after 14 and 43 months, respectively. The H pylori strains responsible for these reinfections, the corresponding pretreatment isolates, and the strains isolated from the spouses of these patients were examined by polymerase chain reaction based DNA fingerprinting. Analysis showed that reinfection had been caused by the same H pylori strain and identified the spouses of these patients as carriers of the identical strain. Considering the genomic diversity and the interpatient heterogeneity of H pylori these results suggest a person to person transmission of H pylori reinfection. By the end of the observation period reflux oesophagitis had developed in 10 of the 16 patients who had not been reinfected. This surprising finding may be explained by the changed eating habits of patients after healing of duodenal ulcer disease.

Helicobacter pylori eradication in the African setting, with special reference to reinfection and duodenal ulcer recurrence

The aim of this study was to determine the effect of Helicobacter pylori eradication on the natural history of duodenal ulcer disease, and to determine the incidence of reinfection in adult patients where H pylori had been eradicated in a community with a high prevalence of the infection. An investigator blinded study, with 24 month endoscopic follow up, in subjects where H pylori had been eradicated, and similarly treated subjects where it had not been eradicated was conducted at a tertiary referral hospital. The patients consisted of a volunteer sample of 48 patients with endoscopically proved active duodenal ulcer disease. Duodenal ulcers were healed with omeprazole, 20 mg/day. After endoscopically confirmed healing, patients were treated with either one (17 patients) or two weeks (31 patients) of 'triple therapy'. H pylori status (urease reaction, histological tests, and culture of antral biopsy specimens) was determined at entry, four weeks after the finish of triple therapy and six, 12, and 24 months after this, or whenever an endoscopically proved recurrent duodenal ulcer was found. The main outcome measures were the recurrence of duodenal ulceration, over 24 months in the eradicated and non-eradicated groups and the incidence of reinfection by H pylori in the eradicated group during this follow up period. Five patients in the eradicated group experienced a duodenal ulcer relapse, of which only three were unexplained (1 = reinfected, 1 = gastrinoma). Fifteen of 21 patients in the non-eradicated group relapsed over the same period (p < 0.001). Only two of 27 patients in the eradicated group were reinfected during the 24 month follow up period. It is concluded that H pylori eradication is an effective treatment strategy for the longterm treatment of duodenal ulcer disease, even in the high prevalence, African setting. Reinfection is uncommon.

Triple therapy with ranitidine, clarithromycin, and metronidazole in the treatment of Helicobacter pylori

BACKGROUND

To determine whether a triple therapy regimen for the treatment of Helicobacter pylori infection, consisting of ranitidine 300 mg q.i.d., clarithromycin 500 mg t.i.d., and metronidazole 500 mg t.i.d. would provide a safe and effective treatment regimen, we performed an open prospective study in 20 consecutive patients with proven H. pylori-associated non-ulcer dyspepsia or peptic ulcer disease.

METHODS

The percentage of patients in whom eradication of H. pylori succeeded was determined. A semiquantitative assessment of histology was performed, and the results were analysed using Wilcoxon's matched-pairs ranks tests; side effects were noted and graded.

RESULTS

Eradication was achieved in 19 of 20 patients, i.e. in 95% (confidence interval 85-100%). Eradication of the bacterium led to a significant improvement in semiquantitative histology scores; active antral inflammation decreased from (mean +/- SEM) 1.84 +/- 0.19 to 0.21 +/- 0.16 (p = 0.0004) and chronic antral inflammation from 2.47 +/- 0.14 to 1.16 +/- 0.14 (p = 0.0002); active gastric body inflammation decreased from 0.95 +/- 0.19 to 0.00 +/- 0.00 (p = 0.0015) and chronic inflammation from 1.68 +/- 0.17 to 0.32 +/- 0.11 (p = 0.0007). Side effects occurred in 45% of patients, but in over half of these patients only mild side effects occurred. Severe side effects did not occur, none of the patients discontinued the triple therapy.

CONCLUSIONS

Triple therapy with ranitidine, clarithromycin, and metronidazole provides a safe and effective treatment of H. pylori infection, resulting in a high eradication rate, and in significant decrease in semiquantitative histology scores. Further prospective studies are warranted.

Quality of life and relapse of duodenal ulcer before and after eradication of Helicobacter pylori

BACKGROUND

The aim of the study was to compare relapse rates and quality of life before and after eradication of Helicobacter pylori in a group of patients with documented recurrent duodenal ulcer disease.

METHODS

Seventy-four patients with three endoscopically verified duodenal ulcers during the past 2 years received triple treatment consisting of bismuth subnitrate, oxytetracycline, and metronidazole for 14 days. Quality of life was measured with the Psychosocial Adjustment to Illness Scale (PAIS-SR) and H. pylori status with the 14C-urea breath test.

RESULTS

After triple treatment H. pylori was eradicated in 96%, and the ulcer was healed in all. Ulcer relapse was reduced from 100% before to 1.4% during a mean observation time of 111 weeks. The H. pylori reinfection rate was 2.4% during the 1st year. The patients were more satisfied with the health care system and had better sexual relationship and less psychologic distress 1 year after eradication of H. pylori than before.

CONCLUSIONS

For patients with recurrent duodenal ulcer, eradication of H. pylori with triple treatment leads to a significantly reduced ulcer relapse rate and improved quality of life.

Helicobacter pylori: the missing link in perspective

Helicobacter pylori, an organism responsible for a common human infection, may act as a cofactor to produce gastrointestinal disease in a significant minority. The exact mechanisms of transmission are still unclear, but likely involve direct person-to-person spread and fecal-oral or waterborne/environmental transmission. Infection is a necessary condition for the development of duodenal ulcers and chronic nonspecific gastritis. It also likely contributes to the development of gastric ulcers, and the intestinal-type gastric carcinoma, but further studies are needed to confirm these hypotheses. Multiple effective treatment regimens currently exists. We recommend using bismuth, metronidazole, and tetracycline as the initial regimen of choice. Unfortunately, the relative importance of bacterial virulence factors is still unclear when compared with host susceptibility factors, and much knowledge needs to be gained about pathogenesis before vaccine development can proceed.

Review article: Helicobacter pylori eradication--understandable caution but no excuse for inertia

The long-term management of patients with peptic ulcer disease is unsatisfactory, as judged by the persistently high levels of haemorrhage, perforation and death from this condition in Western countries. Although ulcer recurrence and complications can be prevented, many patients with peptic ulcer disease fail to receive the benefits of modern therapeutic regimens. In recent years, eradication of Helicobactor pylori has been promoted as a 'cure' for peptic ulcer disease and, while such claims are premature, there can be little doubt that this treatment--when successful--dramatically improves the medium-term prognosis of ulcer patients. However, in general, clinicians have given this promising therapeutic advance a lukewarm welcome. The aim of this detailed review of the literature is to remove the uncertainty and confusion surrounding many aspects of eradication therapy. Estimates are provided of the eradication rates after either triple therapy or the combination of omeprazole plus amoxycillin, and the sources of variation in published studies are discussed. Problems associated with eradication therapy, including side effects, compliance and re-infection, are addressed in order to ascertain the extent and clinical significance of each factor. In addition, studies reporting the outcome of patients with peptic ulcer disease after eradication are assessed with reference to both ulcer recurrence and complications. The result of the review is to dissipate much of the scepticism concerning eradication therapy. However, whilst acknowledging the efficacy of eradication therapy, its limitations have also to be recognized. By itself, it does not provide the complete answer to peptic ulcer disease. For some ulcer patients, eradication therapy is the preferred option; for others, prophylactic therapy with H2-receptor antagonists is more suitable. Guidelines are proposed for the selection of patients for each alternative therapy. The crucial point is that patients with peptic ulcer--excluding the small proportion with a mild form of the disease--require positive, long-term management consisting of either continuous prophylaxis with H2-receptor antagonists or the eradication of Helicobacter pylori.

Review article: treatments that impact favourably upon the eradication of Helicobacter pylori and ulcer recurrence

Healing the gastroduodenal mucosa through Helicobacter pylori eradication leads to a dramatic reduction in gastroduodenal ulcer relapse. Eradication of H. pylori proves to be difficult. Although the organism is sensitive to many antibiotics in vitro, the in vivo eradicating efficacy is often disappointing. This overview summarizes the most commonly used currently-available eradication schemes and the consequences of successful eradication in peptic ulcer disease.

The effect of eradication of Helicobacter pylori upon the duodenal ulcer recurrence--a 24 month follow-up study

OBJECTIVES

To evaluate the effect of eradication of Helicobacter pylori(H.pylori) in the patients with duodenal ulcer(Du) upon the DU recurrence.

METHODS

This study was performed for 190 patients with DU. Four different methods-microscopy of Gram stained mucosal smear, specific culture, biopsy urease test, histology of H &E staining-were taken for identifying colonization of H. pylori before treatment, and for finding the eradication of H. pylori 4 weeks after completion of therapy in each treatment group (cometidine, omeprazole, colloidal bismuth subcitrate(CBS), CBS and metronidazole double therapy, CBS, metronidazole and amoxicillin triple therapy). To detect DU recurrence, the gastroscopy was performed at 6, 12, 18, and 24 months after therapy.

RESULTS

The eradication rate of the cimetidine group the omeprazole group, and the CBS group were 0%, 7.7%, 0%, respectively, and that of the double therapy group and the triple therapy group were 44.4% and 89.3%, respectively. Seventy three patients who were followed up for 2 years were categorized into two groups according to the eradication of H. pylori. The recurrence rate was 3.2% both in 1 year and 2 years later in the former group-one consisting of 31 patients with H. pylori eradicated, while the recurrence rate was 57.1% in 1 year and 78.6% in 2 years later, in the latter group-the other of 42 patients with H. pylori not eradicated.

CONCLUSION

The eradication of H. pylori in patients with DU reduces the recurrence of DU.