N-acetyl cysteine as an adjunct to standard anti-Helicobacter pylori eradication regimen in patients with dyspepsia: A prospective randomized, open-label trial

Rapid diagnosis and precision treatment of Helicobacter pylori infection in clinical settings

Helicobacter pylori is a gram-negative bacterium that colonizes the stomach of approximately half of the worldwide population, with higher prevalence in densely populated areas like Asia, the Caribbean, Latin America, and Africa. H. pylori infections range from asymptomatic cases to potentially fatal diseases, including peptic ulcers, chronic gastritis, and stomach adenocarcinoma. The management of these conditions has become more difficult due to the rising prevalence of drug-resistant H. pylori infections, which ultimately lead to gastric cancer and mucosa-associated lymphoid tissue (MALT) lymphoma. In 1994, the International Agency for Research on Cancer (IARC) categorized H. pylori as a Group I carcinogen, contributing to approximately 780,000 cancer cases annually. Antibiotic resistance against drugs used to treat H. pylori infections ranges between 15% and 50% worldwide, with Asian countries having exceptionally high rates. This review systematically examines the impacts of H. pylori infection, the increasing prevalence of antibiotic resistance, and the urgent need for accurate diagnosis and precision treatment. The present status of precision treatment strategies and prospective approaches for eradicating infections caused by antibiotic-resistant H. pylori will also be evaluated.

The efficacy of adjuvant N acetyl cysteine for the eradication of H pylori infections: A systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Biofilm-producing bacteria are relatively resistant to antibiotics, as the penetration of antibiotics into the endopolysaccharide envelope is incomplete. N Acetyl cysteine (NAC) is known to destabilize the biofilms, as it cleaves the disulfide bonds of mucus glycoproteins, reducing the viscosity and thickness of mucus. This allows NAC to act synergistically with antibiotics for the eradication of H Pylori. The meta-analysis evaluates the evidence of the efficacy of adjuvant N acetyl cysteine (NAC) compared to standard therapies in the eradication of H. Pylori infections.

METHODS

We searched randomized clinical trials in MEDLINE, Cochrane Central Register of Clinical Trials (CENTRAL), EBSCO, Database of Abstracts of Reviews of Effects (DARE), and Google Scholar. We included trials comparing standard treatment protocols plus adjuvant NAC and the same regimen without NAC. These studies included adults with a diagnosis of Helicobacter pylori infection. Our primary outcome was the successful eradication of H. Pylori. The results were pooled using a random-effects model, and data were analyzed using RevMan 5.0 software. Cochrane collaboration's tool was used to assess the risk of bias. Publication bias and other inconsistencies were assessed. Sensitivity analyses and grading of evidence were performed.

FINDINGS

Eight studies, comprising 1167 patients, were included in the meta-analysis, the pooled outcomes of patients on adjuvant NAC+ standard eradication therapy noted an eradication rate of 76.1% (n=581) compared to the patients in standard eradication therapy with a rate of 72.18% (n=586), RR 1.17 [95% CI (0.99, 1.39); I2= 64%; p value=0.07]. Moderate to severe heterogeneity was noted. These pooled results show that adjuvant NAC plus standard treatment protocols are not superior to standard treatment protocols for H pylori eradication. Similar results were seen in the use of adjuvant NAC with 'currently used standard treatment protocols' (78.3% versus 76.3%, RR 1.08, [95% CI 0.94 to 1.25]; I2=55%; p=0.28; n= 829 patients], as well as in the treatment of naïve patients (79.8% versus 80.9%, RR 1.00[95% CI 0.87 to 1.15]; i2=27%; P=-0.98; n= 775 patients].

CONCLUSION

Adjuvant NAC plus standard treatment protocols are not superior to standard treatment protocols for H. pylori eradication. These findings are consistent with the use of adjuvant NAC with 'currently used standard treatment protocols' (clarithromycin-based triple therapies) and also with adjuvant NAC used in the treatment of naïve patients. We are moderately certain of these findings. Future studies could explore the use of NAC as a pretreatment before using the current standard therapies in the eradication of H. Pylori rather than NAC as adjuvant therapy.

FUNDING

None.

Comparison of the effect of clarithromycin triple therapy with or without N-acetylcysteine in the eradication of Helicobacter pylori: a randomized controlled trial

BACKGROUND

Whether adjunctive N-acetylcysteine (NAC) may improve the efficacy of triple therapy in the first-line treatment of Helicobacter pylori infection remains unknown. Our aim was to compare the efficacy of 14-day triple therapy with or without NAC for the first-line treatment of H. pylori.

MATERIAL AND METHODS

Between 1 January 2014 and 30 June 2018, 680 patients with H. pylori infection naïve to treatment were enrolled in this multicenter, open-label, randomized trial. Patients were randomly assigned to receive triple therapy with NAC [NAC-T14, dexlansoprazole 60 mg four times daily (q.d.); amoxicillin 1 g twice daily (b.i.d.), clarithromycin 500 mg b.i.d., NAC 600 mg b.i.d.] for 14 days, or triple therapy alone (T14, dexlansoprazole 60 mg q.d.; amoxicillin 1 g b.i.d., clarithromycin 500 mg b.i.d.) for 14 days. Our primary outcome was the eradication rates by intention to treat (ITT). Antibiotic resistance and CYP2C19 gene polymorphism were determined.

RESULTS

The ITT analysis demonstrated H. pylori eradication rates in NAC-T14 and T14 were 81.7% [276/338, 95% confidence interval (CI): 77.5-85.8%] and 84.3% (285/338, 95% CI 80.4-88.2%), respectively. In 646 participants who adhered to their assigned therapy, the eradication rates were 85.7% and 88.0% with NAC-T14 and T14 therapies, respectively. There were no differences in compliance or adverse effects. The eradication rates in subjects with clarithromycin-resistant, amoxicillin-resistant, or either clarithromycin/amoxicillin resistant strains were 45.2%, 57.9%, and 52.2%, respectively, for NAC-T14, and were 66.7%, 76.9%, and 70.0%, respectively, for T14. The efficacy of NAC-T14 and T14 was not affected by CYP2C19 polymorphism.

CONCLUSION

Add-on NAC to triple therapy was not superior to triple therapy alone for first-line H. pylori eradication [ClinicalTrials.gov identifier: NCT02249546].

N-acetylcysteine as an adjuvant therapy for Helicobacter pylori eradication

BACKGROUND

Helicobacter pylori (H pylori) is one of the most common pathogens to establish and cause infection in human beings, affecting about 50% of the world's population. Prevalence may be as high as 83% in Latin American countries and as low as 17% in North America. Approximately 20% of infected people will manifest disease; people at high risk include those who live in low- and middle-income countries with poor sanitary conditions, since the mechanism of transmission seems to be oral-oral or faecal-oral (mostly during infancy). There are several antibiotic regimens to treat the infection, but antibiotic resistance is growing around the world. New adjuvant drugs - such as probiotics, statins, curcumin, and N-acetylcysteine (NAC) - are being tested to enhance eradication rates.N-acetylcysteine can destabilise the biofilm structure; it also has synergic action with antibiotics, and bactericidal effects. In addition, NAC has antioxidant properties, and has a primary mucolytic effect by reducing the thickness of the gastric mucus layer, both of which may exert beneficial adjuvant effects on H pylori eradication.

OBJECTIVES

To assess the efficacy and safety of N-acetylcysteine as an adjuvant therapy to antibiotics for Helicobacter pylori eradication.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (1966 to April 2018), Embase (1988 to April 2018), CINAHL (1982 to April 2018), LILACS (1982 to April 2018), grey literature databases and trials registries. We handsearched the reference lists of relevant studies. We screened 726 articles and assessed 18 for eligibility.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of any antibiotic regimen plus NAC, in adults infected with H pylori. To be included, trials had to use a control consisting of the same antibiotic regimen with or without placebo. Outcomes of interest were eradication rates, and gastrointestinal, toxic, and allergic adverse events. Reporting of the primary outcomes listed here was not an inclusion criterion for the review.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed and extracted data and completed the 'Risk of bias' assessments. A third review author independently confirmed the 'Risk of bias' assessments. We used Review Manager 5 software for data analysis. We contacted study authors if there was missing information.

MAIN RESULTS

We included eight RCTs (with a total of 559 participants) in this review. The studies recruited outpatients aged between 17 and 76 years who were referred to endoscopy centres in several different countries. The certainty of evidence was reduced for most outcomes due to the poor methodological quality of included studies; issues mainly related to the generation of allocation sequence, allocation concealment, and blinding (this last domain related specifically to adverse outcomes).We are uncertain whether the addition of NAC to antibiotics improves H pylori eradication rates, compared with the addition of placebo or no NAC (38.8% versus 49.1%, risk ratio (RR) 0.74, 95% confidence interval (CI) 0.51 to 1.08; participants = 559; studies = eight; very low-certainty evidence). A post-hoc sensitivity analysis, in which we removed studies that tested antibiotic regimens no longer recommended in clinical practice, showed that the addition of NAC may improve eradication rates compared to control (27.2% versus 37.6%, RR 0.71, 95% CI 0.53 to 0.94; participants = 397; published studies = five).We are uncertain whether NAC is associated with a higher risk of gastrointestinal adverse events compared to control (23.9% versus 18.9%, RR 1.25, 95% CI 0.85 to 1.85; participants = 336; studies = five; very low-certaintyevidence), or allergic adverse events (2% versus 0%, RR 2.98, 95% CI 0.32 to 27.74; participants = 336; studies = five; very low-certainty evidence). There were no reports of toxic adverse events amongst included studies.

AUTHORS' CONCLUSIONS

We are uncertain whether the addition of NAC to antibiotics improves H pylori eradication rates compared with the addition of placebo or no NAC. Due to the clinical, statistical and methodological heterogeneity found in included studies, and the uncertainty observed when analysing therapy subgroups, any possible beneficial effect of NAC should be regarded cautiously.We are uncertain whether NAC is associated with a higher risk of gastrointestinal or allergic adverse events compared with placebo or no NAC. There were no reports of toxic adverse events amongst the included studies.Further large, well-designed, randomised clinical studies should be conducted, with good reporting standards and appropriate collection of efficacy and safety outcomes, especially for current recommended antibiotic regimens.

The effect of antioxidants on Helicobacter pylori eradication: A systematic review with meta-analysis

BACKGROUND

The efficacy and safety of the addition of antioxidants to triple or quadruple therapy were unclear.

MATERIALS AND METHODS

This systematic review was performed in accordance with the PRISMA 2009 guidelines. A systematic search of PubMed, EMBASE, and the Cochrane Library databases was conducted to identify potentially relevant publications using the following keywords: ([Helicobacter pylori] or [H. pylori] or [Hp]) and ([antioxidant] or [vitamin] or [N-acetylcysteine] or [curcumin] or [cranberry]). The primary end-point of this study was to evaluate the efficacy of the addition of antioxidants to triple or quadruple therapy according to ITT and PP analysis. The second end-points were side effects and the comparative efficacy in terms of H. pylori eradication according to different antioxidant and antibiotic combinations.

RESULTS

We included 9 studies with 1260 participants. The total eradication rate of H. pylori in the group combining eradication therapy with antioxidants was not superior to that without antioxidants according to the ITT (pooled RR [95% CI] = 1.17 [0.99-1.38]; P = 0.07) and PP analysis (pooled RR [95% CI] = 1.15 [0.99-1.34; P = 0.07]. There were no differences regarding side effects between the two groups (pooled RR [95% CI], 1.36 [0.81-2.28]; P = 0.24). However, the eradication regimen with vitamin supplementation (1400 mg/day) showed a significant, superior efficacy in eradication relative to those without supplementation (pooled RR [95% CI] = 1.57 [1.35, 1.84]; P < 0.01). In particular, in the amoxicillin-clarithromycin-based subgroup, the crude H. pylori eradication rate determined by ITT analysis was 81.3% and 68.6% for eradication therapy with and without antioxidant supplementation, respectively, which was a statistically significant difference (pooled RR [95% CI] = 1.23 [1.02-1.49]; P = 0.03).

CONCLUSIONS

The addition of antioxidants (vitamin, N-acetylcysteine, curcumin, cranberry) to amoxicillin-clarithromycin-based therapy could improve the eradication rate, and vitamin supplementation might be effective at a high dosage. However, antioxidant supplements have no impact on improving side effects.