Successful eradication of Helicobacter pylori prevents relapse of peptic ulcer disease

Role of the Gastric Microbiome in Gastric Cancer: From Carcinogenesis to Treatment

The development of sequencing technology has expanded our knowledge of the human gastric microbiome, which is now known to play a critical role in the maintenance of homeostasis, while alterations in microbial community composition can promote the development of gastric diseases. Recently, carcinogenic effects of gastric microbiome have received increased attention. Gastric cancer (GC) is one of the most common malignancies worldwide with a high mortality rate. Helicobacter pylori is a well-recognized risk factor for GC. More than half of the global population is infected with H. pylori, which can modulate the acidity of the stomach to alter the gastric microbiome profile, leading to H. pylori-associated diseases. Moreover, there is increasing evidence that bacteria other than H. pylori and their metabolites also contribute to gastric carcinogenesis. Therefore, clarifying the contribution of the gastric microbiome to the development and progression of GC can lead to improvements in prevention, diagnosis, and treatment. In this review, we discuss the current state of knowledge regarding changes in the microbial composition of the stomach caused by H. pylori infection, the carcinogenic effects of H. pylori and non-H. pylori bacteria in GC, as well as the potential therapeutic role of gastric microbiome in H. pylori infection and GC.

Theoretical investigation of stochastic clearance of bacteria: first-passage analysis

Understanding mechanisms of bacterial eradication is critically important for overcoming failures of antibiotic treatments. Current studies suggest that the clearance of large bacterial populations proceeds deterministically, while for smaller populations, the stochastic effects become more relevant. Here, we develop a theoretical approach to investigate the bacterial population dynamics under the effect of antibiotic drugs using a method of first-passage processes. It allows us to explicitly evaluate the most important characteristics of bacterial clearance dynamics such as extinction probabilities and extinction times. The new meaning of minimal inhibitory concentrations for stochastic clearance of bacterial populations is also discussed. In addition, we investigate the effect of fluctuations in population growth rates on the dynamics of bacterial eradication. It is found that extinction probabilities and extinction times generally do not correlate with each other when random fluctuations in the growth rates are taking place. Unexpectedly, for a significant range of parameters, the extinction times increase due to these fluctuations, indicating a slowing in the bacterial clearance dynamics. It is argued that this might be one of the initial steps in the pathway for the development of antibiotic resistance. Furthermore, it is suggested that extinction times is a convenient measure of bacterial tolerance.

Antibiotic-induced population fluctuations and stochastic clearance of bacteria

Effective antibiotic use that minimizes treatment failures remains a challenge. A better understanding of how bacterial populations respond to antibiotics is necessary. Previous studies of large bacterial populations established the deterministic framework of pharmacodynamics. Here, characterizing the dynamics of population extinction, we demonstrated the stochastic nature of eradicating bacteria with antibiotics. Antibiotics known to kill bacteria (bactericidal) induced population fluctuations. Thus, at high antibiotic concentrations, the dynamics of bacterial clearance were heterogeneous. At low concentrations, clearance still occurred with a non-zero probability. These striking outcomes of population fluctuations were well captured by our probabilistic model. Our model further suggested a strategy to facilitate eradication by increasing extinction probability. We experimentally tested this prediction for antibiotic-susceptible and clinically-isolated resistant bacteria. This new knowledge exposes fundamental limits in our ability to predict bacterial eradication. Additionally, it demonstrates the potential of using antibiotic concentrations that were previously deemed inefficacious to eradicate bacteria.

Hybrid Therapy versus Sequential Therapy for Eradication of Helicobacter pylori: A Randomized Controlled Trial

Objective:

To compare the sequential therapy (ST) with the hybrid therapy (HT) for the eradication of Helicobacter pylori.

Materials and Methods:

Patients with peptic ulcer disease and gastritis found to be H. pylori positive were randomized to HT group who received omeprazole (20 mg bid) and amoxicillin (1 g bid) for 7 days followed by omeprazole (20 mg bid), amoxicillin (1 g bid), clarithromycin (500 mg bid), and metronidazole (400 mg tid) for the next 7 days and ST group who received omeprazole and amoxicillin for 5 days followed by omeprazole, clarithromycin, and metronidazole for the next 5 days. Eradication rate, compliance, and complications were compared.

Results:

A total of 120 patients were included, sixty in each group. H. pylori eradication rate was significantly higher in HT group on intention-to-treat analysis (88.3% [confidence interval (CI) 78.3%–94.8%] vs. 73.3% [CI 61.1%–83.3%]; P = 0.037). Per-protocol analysis showed higher eradication rate with HT (93% [CI 83.9%–93.7%] vs. 81.5% [CI 69.5%–90.2%]; P = 0.068); however, the difference was insignificant. Compliance and side effects were similar. A complete course of HT costs $10.77, while ST costs only $6.347.

Conclusions:

HT achieves significantly higher H. pylori eradication rate than ST with comparable patient compliance and side effects but at an higher price. However, it can be used in places where ST is ineffective.

Eradication therapy for peptic ulcer disease in Helicobacter pylori-positive people

BACKGROUND

Peptic ulcer disease is the cause of dyspepsia in about 10% of people. Ninety-five percent of duodenal and 70% of gastric ulcers are associated with Helicobacter pylori. Eradication of H. pylori reduces the relapse rate of ulcers but the magnitude of this effect is uncertain. This is an update of Ford AC, Delaney B, Forman D, Moayyedi P. Eradication therapy for peptic ulcer disease in Helicobacter pylori-positive patients. Cochrane Database of Systematic Reviews 2006, Issue 2. Art. No.: CD003840. DOI: 10.1002/14651858.CD003840.pub4.

OBJECTIVES

To assess the proportion of peptic ulcers healed and the proportion of participants who remained free from relapse with eradication therapy against placebo or other pharmacological therapies in H. pylori-positive people.To assess the proportion of participants that achieved complete relief of symptoms and improvement in quality of life scores.To compare the incidence of adverse effects/drop-outs (total number for each drug) associated with the different treatments.To assess the proportion of participants in whom successful eradication was achieved.

SEARCH METHODS

In this update, we identified trials by searching the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE (1950 to March 2016) and Ovid EMBASE (1980 to March 2016). To identify further relevant trials, we handsearched reference lists from trials selected by electronic searching, and published abstracts from conference proceedings from the United European Gastroenterology Week (published in Gut) and Digestive Disease Week (published in Gastroenterology). The search was last updated in March 2016. We contacted members of Cochrane Upper GI and Pancreatic Diseases, and experts in the field and asked them to provide details of outstanding clinical trials and any relevant unpublished materials.

SELECTION CRITERIA

We analysed randomised controlled trials of short- and long-term treatment of peptic ulcer disease in H. pylori-positive adults. Participants received at least one week of H. pylori eradication compared with ulcer healing drug, placebo or no treatment. Trials were included if they reported assessment from two weeks onwards.

DATA COLLECTION AND ANALYSIS

We collected data on ulcer healing, recurrence, relief of symptoms and adverse effects. We calculated the risk ratio (RR) with 95% confidence intervals (CI) using both fixed-effect and random-effects models with Review Manager software (RevMan 5.3) based on intention-to-treat analysis as far as possible.

MAIN RESULTS

A total of 55 trials were included for one or more outcomes for this review.In duodenal ulcer healing, eradication therapy was superior to ulcer healing drug (UHD) (34 trials, 3910 participants, RR of ulcer persisting = 0.66, 95% confidence interval (CI) 0.58 to 0.76; 381/2286 (adjusted proportion: 12.4%) in eradication therapy plus UHD versus 304/1624 (18.7%) in UHD; low quality evidence) and no treatment (two trials, 207 participants, RR 0.37, 95% CI 0.26 to 0.53; 30/125 (adjusted proportion: 21.7%) in eradication therapy versus 48/82 (58.5%) in no treatment; low quality evidence).In gastric ulcer healing, the differences were imprecise between eradication therapy and UHD (15 trials, 1974 participants, RR 1.23, 95% CI 0.90 to 1.68; 220/1192 (adjusted proportion: 16.0%) in eradication therapy plus UHD versus 102/782 (13.0%) in UHD; very low quality evidence). In preventing duodenal ulcer recurrence the differences were imprecise between maintenance therapy with H.pylori eradication therapy and maintenance therapy with UHD (four trials, 319 participants, RR of ulcer recurring 0.73; 95% CI 0.42 to 1.25; 19/159 (adjusted proportion: 11.9%) in eradication therapy versus 26/160 (16.3%) in UHD; very low quality evidence), but eradication therapy was superior to no treatment (27 trials 2509 participants, RR 0.20, 95% CI 0.15 to 0.26; 215/1501 (adjusted proportion: 12.9%) in eradication therapy versus 649/1008 (64.4%) in no treatment; very low quality evidence).In preventing gastric ulcer recurrence, eradication therapy was superior to no treatment (12 trials, 1476 participants, RR 0.31, 95% CI 0.22 to 0.45; 116/697 (adjusted proportion: 16.3%) in eradication therapy versus 356/679 (52.4%) in no treatment; very low quality evidence). None of the trials reported proportion of people with gastric ulcer not healed after initial therapy between H.pylori eradication therapy and no active treatment or the proportion of people with recurrent gastric ulcer or peptic ulcers during maintenance therapy between H.pylori eradication therapy and ulcer healing drug therapy.

AUTHORS' CONCLUSIONS

Adding a one to two-week course of H. pylori eradication therapy is an effective treatment for people with H. pylori-positive duodenal ulcer when compared to ulcer healing drugs alone and no treatment. H. pylori eradication therapy is also effective in preventing recurrence of duodenal and gastric ulcer compared to no treatment. There is currently no evidence that H. pylori eradication therapy is an effective treatment in people with gastric ulcer or that it is effective in preventing recurrence of duodenal ulcer compared to ulcer healing drug. However, confidence intervals were wide and significant benefits or harms of H. pylori eradication therapy in acute ulcer healing of gastric ulcers compared to no treatment, and in preventing recurrence of duodenal ulcers compared to ulcer healing drugs cannot be ruled out.

First case of Helicobacter pylori infection resistant to seven antibiotics in Iran

Treatment of Helicobacter pylori infection with common antibiotics is typically recommended for several digestive conditions, including peptic ulcers. However, reports of resistant H. pylori isolates are increasing, and unfortunately, these do not respond to currently available therapeutic regimens. We report the case of a 31-year-old woman with two peptic ulcers in the duodenal antrum. An H. pylori strain was isolated, and tested for antibiotic resistance using agar dilution and disk diffusion. The isolated strain was found to be resistant to all seven antibiotics that were tested. Therefore, constant monitoring for antibiotic resistance should be performed prior to initiating antibiotic therapy.

Trends and predictors for vagotomy when performing oversew of acute bleeding duodenal ulcer in the United States

BACKGROUND

In the era of Helicobacter pylori treatment, the role of vagotomy in bleeding duodenal ulcers is debatable. National outcomes were evaluated to determine the current surgical treatment and use of vagotomy for bleeding duodenal ulcers.

METHODS

Data from the Nationwide Inpatient Sample (NIS) were used from years 1999 to 2003. Patients were selected using diagnostic codes for acute duodenal ulcer bleed and procedure codes for simple oversew of a bleeding ulcer and vagotomy. Data were analyzed using multiple linear and logistic regression.

RESULTS

Between 1999 and 2003, 100,931 patients with an acute bleeding duodenal ulcer were identified. Over time, there was a decrease in the number of acute bleeding ulcers (p = 0.027) and a decrease in the number of vagotomies (p = 0.027). A high co-morbidity index [odds ratio (OR), 0.60, p = 0.017], operation in the Midwest (OR 0.50, p < 0.001) and operation in the West (OR 0.68, p = 0.034) were predictive of no vagotomy during surgery for a bleeding duodenal ulcer.

CONCLUSIONS

A vagotomy is not commonly performed during surgical treatment of an acute bleeding duodenal ulcer. This variation in practice was not fully explained by patient characteristics. We must seek new evidence to determine the safety of combined medical and surgical management of this clinical problem.

Eradication therapy for peptic ulcer disease in Helicobacter pylori positive patients

BACKGROUND

Peptic ulcer disease is the cause for dyspepsia in about 10% of patients. 95% of duodenal and 70% of gastric ulcers are associated with Helicobacter pylori. Eradication of H pylori reduces the relapse rate of ulcers but the magnitude of this effect is uncertain.

OBJECTIVES

The primary outcomes were the proportion of peptic ulcers healed initially and proportion of patients free from relapse following successful healing. Eradication therapy was compared to placebo or pharmacological therapies in H. pylori positive patients. Secondary aims included symptom relief and adverse effects.

SEARCH STRATEGY

Searches were conducted on the Cochrane Central register of Controlled Trials - CENTRAL (which includes the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group Trials Register) on The Cochrane Library (Issue 3 2002) MEDLINE (1966 to July 2002) and EMBASE (1980 to July 2002). Reference lists from trials selected by electronic searching were handsearched to identify further relevant trials. Published abstracts from conference proceedings from the United European Gastroenterology Week (published in Gut) and Digestive Disease Week (published in Gastroenterology) were handsearched. The search was updated in September 2003, November 2004 and November 2005. Members of the Cochrane UGPD Group, and experts in the field were contacted and asked to provide details of outstanding clinical trials and any relevant unpublished materials

SELECTION CRITERIA

Randomised controlled trials of short and long-term treatment of peptic ulcer disease in H. pylori positive adults were analysed. Patients received at least one week of H pylori eradication compared with ulcer healing drug, placebo or not treatment. Trials were included if they reported assessment from 2 weeks onwards.

DATA COLLECTION AND ANALYSIS

Data were collected on ulcer healing, recurrence, relief of symptoms and adverse effects.

MAIN RESULTS

63 trials were eligible. Data extraction was not possible in 7 trials, and 56 trials were included. In duodenal ulcer healing, eradication therapy was superior to ulcer healing drug (UHD) (34 trials, 3910 patients, relative risk [RR] of ulcer persisting = 0.66; 95% confidence interval [CI] = 0.58, 0.76) and no treatment (2 trials, 207 patients, RR = 0.37; 95% CI 0.26, 0.53). In gastric ulcer healing, no significant differences were detected between eradication therapy and UHD (14 trials, 1572 patients, RR = 1.25; 95% CI = 0.88, 1.76). In preventing duodenal ulcer recurrence no significant differences were detected between eradication therapy and maintenance therapy with UHD (4 trials, 319 patients, relative risk [RR] of ulcer recurring = 0.73; 95% CI = 0.42, 1.25), but eradication therapy was superior to no treatment (27 trials 2509 patients, RR = 0.20; 95% CI = 0.15, 0.26). In preventing gastric ulcer recurrence, eradication therapy was superior to no treatment (11 trials, 1104 patients, RR = 0.29; 95% CI 0.20, 0.42).

AUTHORS' CONCLUSIONS

A 1 to 2 weeks course of H. pylori eradication therapy is an effective treatment for H. pylori positive peptic ulcer disease.

Long-term follow-up after eradication of Helicobacter pylori with omeprazole, clarithromycin, and tinidazole (OCT regimen) in a Japanese population

BACKGROUND

The long-term benefit of Helicobacter pylori eradication treatment that includes metronidazole on peptic ulcer disease in Japan is unclear. We investigated the rate of H. pylori re-infection and ulcer relapse after H. pylori eradication.

MATERIALS AND METHODS

A total of 266 patients with endoscopically confirmed peptic ulcer disease and H. pylori infection were treated with triple therapy of omeprazole 40 mg (20 mg b.i.d.), clarithromycin 800 mg (400 mg b.i.d.), and tinidazole 1000 mg (500 mg b.i.d.) for 7 days. Endoscopy with gastric biopsy was performed before and 1 month, 6 months, 1.5 years, and 3.5 years after therapy. H. pylori status was determined by H. pylori culture, rapid urease test, and histopathology. 13C-urea breath test was done at 6 months after eradication therapy. Treatment was deemed successful when all tests were negative at 6 months after therapy by endoscopic biopsy.

RESULTS

Successful H. pylori eradication was achieved in 262/266 (98.5%) patients with peptic ulcer. Total relapse of peptic ulcer occurred in 8/262 (3%) patients after eradication, with 3/262 (1.1%) occurring within 1.5 years after treatment and 5/262 (1.9%) within 3.5 years. All relapsed patients were found to be H. pylori-positive at the time of relapse. Of the 262 patients who experienced eradication, 20 (7.6%) were subsequently re-infected, six (2.3%) within 1.5 years and 14 (5.3%) within 3.5 years.

CONCLUSION

Triple therapy with omeprazole, clarithromycin, and tinidazole (OCT) is useful for H. pylori eradication in Japan, but there is an appreciable re-infection rate in this population.

Effects of killing Helicobacter pylori quadruple therapy on peptic ulcer: A randomized double-blind clinical trial

AIM: To study the therapeutic efficacy of a Chinese and Western integrated regimen, killing Helicobacter pylori quadruple therapy on H pylori-associated peptic ulcers (PU).

METHODS: With prospective and double-blind controlled method, seventy-five active PU patients with H pylori infection were randomized to receive one of the following three regimens: (1) new triple therapy (group A: lansoprazole 30 mg qd, plus clarithromycin 250 mg bid, plus amoxycillin 500 mg tid, each for 10 d); (2) killing Hp quadruple therapy(group B: the three above drugs plus killing H pylori capsule 6 capsules bid for 4 wk) and (3) placebo(group C: gastropine 3 tablets bid for 4 wk). H pylori eradication and ulcer healing quality were evaluated under an endoscope 4 wk after treatment. The patients were followed up for 5 years.

RESULTS: Both the healing rate of PU and H pylori eradication rate in group B were significantly higher than those in group C (100% and 96.4% vs 20% and 0%, respectively, P<0.005), but there was no significant difference compared to those in group A (88% and 92%, P>0.05). The healing quality of ulcer in group B was superior to that in groups C and A (P<0.05). The recurrence rate of PU in group B (4%) was lower than that in group A (10%) and group C (100%, P<0.01).

CONCLUSION: Killing Helicobacter pylori quadruple therapy can not only promote the eradication of H pylori and healing quality of ulcer but also reduce recurrence rate of ulcer.

Eradication therapy for peptic ulcer disease in Helicobacter pylori positive patients

BACKGROUND

Peptic ulcer disease is the cause for dyspepsia in about 10% of patients. 95% of duodenal and 70% of gastric ulcers are associated with Helicobacter pylori. Eradication of H pylori reduces the relapse rate of ulcers but the magnitude of this effect is uncertain.

OBJECTIVES

The primary outcomes were the proportion of peptic ulcers healed initially and proportion of patients free from relapse following successful healing. Eradication therapy was compared to placebo or pharmacological therapies in H. pylori positive patients. Secondary aims included symptom relief and adverse effects.

SEARCH STRATEGY

A search was undertaken according to the Cochrane Upper Gastrointestinal and Pancreatic Diseases Review Group module using CCTR, MEDLINE, EMBASE and CINAHL databases. Experts in the field and pharmaceutical companies were contacted. Abstract books between 1994 and 2003 were hand-searched.

SELECTION CRITERIA

Randomised controlled trials of short and long-term treatment of peptic ulcer disease in H. pylori positive adults were analysed. Patients received at least one week of H pylori eradication compared with ulcer healing drug, placebo or not treatment. Trials were included if they reported assessment from 2 weeks onwards.

DATA COLLECTION AND ANALYSIS

Data were collected on ulcer healing, recurrence, relief of symptoms and adverse effects.

MAIN RESULTS

60 trials were eligible. Data extraction was not possible in 7 trials, and 53 trials were included. In duodenal ulcer healing, eradication therapy was superior to ulcer healing drug (UHD) (34 trials, 3910 patients, relative risk [RR] of ulcer persisting = 0.66; 95% confidence interval [CI] = 0.58, 0.76) and no treatment (2 trials, 207 patients, RR = 0.37; 95% CI 0.26, 0.53). In gastric ulcer healing, no significant differences were detected between eradication therapy and UHD (13 trials, 1469 patients, RR = 1.32; 95% CI = 0.92, 1.90). In preventing duodenal ulcer recurrence no significant differences were detected between eradication therapy and maintenance therapy with UHD (4 trials, 319 patients, relative risk [RR] of ulcer recurring = 0.73; 95% CI = 0.42, 1.25), but eradication therapy was superior to no treatment (27 trials 2509 patients, RR = 0.20; 95% CI = 0.15, 0.26). In preventing gastric ulcer recurrence, eradication therapy was superior to no treatment (10 trials, 1029 patients, RR = 0.28; 95% CI 0.18, 0.43).

REVIEWERS' CONCLUSIONS

A 1 to 2 weeks course of H. pylori eradication therapy is an effective treatment for H. pylori positive peptic ulcer disease.

Helicobacter pylori and nonmalignant diseases

Eradication of Helicobacter pylori has lead to a significant decrease in the prevalence of peptic ulcer disease world-wide. Despite the fact that H. pylori eradication is the only way to cure peptic ulcer disease, a substantial number of patients still need antisecretory agents to be symptoms-free after eradication. During the past year several randomized controlled trials on H. pylori eradication in patients taking NSAIDs have been published but contradictory results have been obtained. In certain parts of the world, NSAIDs are becoming the main cause of peptic ulcer disease complications such as bleeding or perforation. Some patients with nonulcer dyspepsia do benefit from eradication of H. pylori as was shown in several studies. Long-term trials with cost/efficacy analysis are still needed to demonstrate the benefit of H. pylori eradication over acid inhibition in this group of patients. H. pylori prevalence is lower in patients with gastro-esophageal reflux disease, but according to recent systematic reviews it varies geographically. There are more data now to show that eradication of H. pylori in duodenal ulcer patients does not increase the incidence of GERD. The 'test and treat' strategy for patients with uninvestigated dyspepsia was strongly supported by both meta-analysis and the results of recent randomized controlled trials. Even in developed countries where the prevalence of H. pylori decreases, this strategy allows resolution of symptoms in a larger number of patients with dyspepsia compared to empirical treatment with proton pump inhibitors and reduces the endoscopic workload.