Metronidazole for Helicobacter pylori eradication therapy among children and adolescents in Japan: Overcoming controversies and concerns

Development of double crosslinked sodium alginate/chitosan based hydrogels for controlled release of metronidazole and its antibacterial activity

Double network sodium alginate/chitosan hydrogels were prepared using calcium chloride (CaCl2) and glutaraldehyde as the crosslinking agents by the ionotropic interaction method for controlled metronidazole release. The effect of polymer ratios and CaCl2 amount is investigated by the developing porosity, gel fraction, and extent of swelling in simulated physiological fluids. Interaction between the polymers with the formation of crosslinked structures, good stability, phase nature, and morphology of the hydrogels is revealed by Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy. A sodium alginate/chitosan hydrogel (weight ratio of 75:25) crosslinked with two percent CaCl2 is chosen for the in-situ loading of 200 mg of metronidazole. The drug release kinetics using different models show that the best-fit Korsmeyer-Peppas model suggests metronidazole release from the matrix follows diffusion and swelling-controlled time-dependent non-Fickian transport related to hydrogel erosion. This composition displays enhanced antimicrobial activity against Staphylococcus aureus and Escherichia coli.

Efficacy and safety of vonoprazan-based regimen for Helicobacter pylori eradication therapy in Japanese adolescents: a prospective multicenter study

BACKGROUND

Vonoprazan (VPZ)-based regimen for Helicobacter pylori (H. pylori) is safe and more efficacious than the proton pump inhibitor-based regimen mainly in adults. This study aimed to evaluate the efficacy and safety of a VPZ-based regimen for H. pylori eradication therapy in adolescents.

METHODS

An H. pylori screening and treatment longitudinal project for third-year junior high school students in Saga Prefecture began in 2016. Students who tested positive for both urine and stool tests received a VPZ-based regimen. On the checklist, students were asked for diarrhea, fever, abdominal pain, nausea, vomiting, urticaria, dysgeusia, or bloody stool occurrence during the therapy.

RESULTS

The longitudinal project for H. pylori screening and treatment among third-grade students in Saga Prefecture targeted 41,115 students from 2017 to 2021 and 836 as positive. Of the 645 students, 542 (84.0% in per protocol [PP] analysis and 73.6% in intention-to-treat [ITT] analysis) were successful in primary eradication therapy. The secondary eradication therapy was successful in 79 (96.3% in PP analysis and 76.7% in ITT analysis) of 82 students. In the primary eradication therapy, abdominal pain occurred in 164 (27.9%), diarrhea in 217 (36.9%), nausea or vomiting in 7 (1.2%), and urticaria in 13 (2.2%) students. In the secondary eradication therapy, abdominal pain occurred in 12 (19.4%) and diarrhea in 17 (27.4%) students. The eradication therapy of 5 students was interrupted due to adverse events only by primary eradication therapy.

CONCLUSIONS

VPZ-based regimen for H. pylori was efficacious and safe for adolescents, as in adults, for both primary and secondary eradication therapies.

Smart Gene™ as an effective non-invasive point-of-care test to detect Helicobacter pylori clarithromycin-resistant mutation

BACKGROUND AND AIM

Smart Gene™ was developed based on the concept of point-of-care genetic testing. We evaluated the detection performance of a reagent for Helicobacter pylori (H. pylori) clarithromycin (CAM)-resistant mutation assessment and determined the association between the results of Smart Gene™ and those of eradication therapy for H. pylori.

METHODS

In 2020, the present study was conducted on participants of the H. pylori test and treat project in Saga Prefecture. The submitted stool samples were measured for H. pylori gene and CAM-resistant mutation by Smart Gene™, and the results were compared with real-time polymerase chain reaction (PCR) and sequencing analysis. Finally, the results of the eradication therapy were examined for each result of Smart Gene™.

RESULTS

Stool samples were obtained from 139 patients who were tested positive by stool antigen test and were analyzed. The H. pylori detection rate was 95.7% by Smart Gene™, 92.8% by real-time PCR (P < 0.01), and 89.2% by sequencing analysis (P = 0.06). The overall concordance rate for CAM-resistant mutation between Smart Gene™ and sequencing analysis was 96.7%. Moreover, 35 of 48 students with CAM-resistant mutation and 33 of the 35 students with a mutation without CAM resistance succeeded in CAM-containing triple therapy, and the success rate was significantly higher for the mutation without CAM resistance (P = 0.012).

CONCLUSIONS

The detection performance of Smart Gene™ was comparable with that of real-time PCR and sequencing analysis. It is expected that the success rate of eradication would be further improved by using the reagent.

Prevalence and eradication efficacy of Helicobacter pylori infection in children in the Mekong delta, Vietnam: a cross-sectional study

Background: Worldwide, Helicobacter pylori (HP) infection in children with peptic ulcer and/or gastritis (PUG) is increasingly common. In Vietnam, clinical symptoms of HP infection in PUG children are often non-specific, and treatment regimens currently have a low success rate.

Objective: This study determined the HP infection prevalence, its clinical and endoscopic findings, and its associated factors. Additionally, the efficiencies of HP treatment regimens in PUG children were also evaluated.

Design and setting: A cross-sectional descriptive study was conducted on 140 pediatric patients diagnosed with PUG at Can Tho Children’s Hospital from 2017–2019.

Results: The prevalence of HP infection in PUG children was 46.4%. A significant association was found between HP infection and patient possessing a family history of HP infection (aOR: 2.35 (1.1–4.76). Symptoms of abdominal pain accounted for the highest rate of 88.6%, followed by vomiting, heartburn, epigastric burning, and gastric bleeding (57.9%, 36.4%, 22.9%, and 13.6%, respectively). Endoscopic findings denoted that inflammatory lesions accounted for 85% and ulcers accounted for 15%. The successful HP eradication rate using the PAM regimen (Proton pump inhibitor/amoxicillin/metronidazole) was 51.8%, with 13.6% of PUG children encountering side effects.

Conclusion: PUG children have a high rate of HP infection. Clinical symptoms are often non-specific, in which abdominal pain is the most common symptom. The success of HP eradication by the standard guideline of the Vietnam Ministry of Health is quite low. Thus, critical adjustments in the regimens are necessary.

Helicobacter pylori Infection in a Pediatric Population from Romania: Risk Factors, Clinical and Endoscopic Features and Treatment Compliance

Background and Objectives: The aim of this study was to investigate the association between H. pylori positivity with specific symptoms, risk factors and endoscopic patterns among the pediatric population in northeastern Romania. Materials and Methods: A prospective study was performed in 18 months on 185 children aged 6−18 years with an indication for upper digestive endoscopy. Demographic, anamnestic, symptomatic, endoscopic and histologic data were recorded. Results: Of 116 H. pylori-positive children, the most affected group was 15−17 years. Most (65.5%) of them were girls, with a significant association (p < 0.001). The majority (66.4%) lived in a rural area and 47.4% of children had an unsafe source of water and lived in overcrowded houses with no basic sanitary comfort. The most frequent symptom was epigastric pain (56.9%), and the main endoscopic appearance was nodularity and hyperemia. Patients diagnosed with H. pylori started triple-therapy treatment for 14 days. Only 13.8% stopped the treatment, mainly because of a misunderstanding of the treatment protocol (9.5%). Conclusions: Romanian teen girls living in rural areas are at high risk for H. pylori infection. Epigastric pain and endoscopic nodularity of the gastric mucosa were associated with the infection. As the resistance of the bacteria is unknown in our country, future research is needed in order to improve the eradication rate.

Graphene-based materials for metronidazole degradation: A comprehensive review

Due to its cytotoxic effect, metronidazole (MNZ) is a drug commonly used to treat bacterial, protozoal, and microaerophilic bacterial infections. After consumption, it undergoes a series of metamorphic reactions that lead to the degradation of oxidized, acetylated, and hydrolyzed metabolites in the environment. To eliminate such pollutants, due to their high potential, adsorption and photocatalysis extensive processes are used in which graphene can be used to improve efficiency. This review analyses the use of graphene as an absorbent and catalyst with a focus on absorption and photocatalytic degradation of MNZ by graphene-based materials (GBMs). The parameters affecting the adsorption, and photocatalytic degradation of MNZ are investigated and discussed. Besides, the basic mechanisms occurring in these processes are summarized and analyzed. This work provides a theoretical framework that can direct future research in the field of MNZ removal from aqueous solutions.

Establishment of a TaqMan-MGB probe multiplex real-time PCR system for one-step levofloxacin and clarithromycin resistant Helicobacter pylori detection

Due to the abuse of antibiotics, the prevalence of antibiotic resistant Helicobacter pylori strains continues to increase. Therefore, antibiotic resistance assessment is now essential in addition to general H. pylori diagnosis in medical institutions to fulfill clinicians administering effective antibiotic regimens. However, the conventional antibiotic resistance assessment methods, such as in vitro antibiotic susceptibility test and E-test, are skilled-staff dependent and time-consuming. The aim of this study was to establish an easy-operating TaqMan-MGB probe multiplex real-time PCR system for one-step detection of levofloxacin and clarithromycin resistance mutations with concurrent H. pylori infection diagnosis. Through the optimization of primers, probes and reaction buffers, this proposed system could accurately distinguish the recombinant plasmids with different mutation markers. More importantly, the diagnosis results of this detection system exhibited excellent consistence with the gold standard of gastric biopsy and Sanger sequencing on the detection of H. pylori infection and relevant antibiotic resistant strains, the Kappa values of which all exceeded 0.90. In addition, the results of this detection system could also be applied for the prevalence statistics of antibiotic resistance patterns for patients by age, gender and geographical location. This simple and rapid system should be beneficial for clinicians issuing personalized treatments according to the patient's H. pylori strains and avoid the abuse of antibiotics.

Recent Changes in the Treatment of Helicobacter pylori Infection in Children and Adolescents

Treatments aimed at eradicating Helicobacter pylori (H. pylori) infections in children and adolescents should be clearly beneficial. According to the updated guidelines, a 14-day triple therapy or bismuth-based triple therapy is the first choice for treatment of children based on the results of antimicrobial sensitivity testing. Though culturing H. pylori using biopsy specimens is not always feasible, it should be performed for establishing empirical rescue therapy for patients not responding to first-line eradication therapy. The European and North American therapeutic strategies for children and adolescents with H. pylori infections may not be appropriate for treating children and adolescents in other countries owing to regional differences in epidemiological characteristics of H. pylori. The existence of clarithromycin-resistant H. pylori is an important factor involved in eradication failure. The development of new treatment-related allergies, treatment failure, side effects, and alteration of the gut microbiome have been highlighted as factors potentially outweighing the possible benefit of preventing future peptic ulcers or gastric cancer. Drug compliance can be improved by providing a detailed explanation of the reason for therapy, duration, and routes of drug administration. Physicians should understand the mechanisms underlying eradication treatment and explain drug prescriptions in detail to both parents and children to increase compliance. Herein, we reviewed the indications for and various modalities of eradication treatment in children with H. pylori infections in accordance with a review of recently published articles.

Nano-scale selective and sensitive optical sensor for metronidazole based on fluorescence quenching: 1H-Phenanthro[9,10-d]imidazolyl-calix[4]arene fluorescent probe

It is crucial to determine and control the metronidazole (MET) ingredient in food and pharmaceuticals for human health and food safety. Even though many sensors have been previously reported to detect MET, there is still a need for a highly selective and sensitive, easy, fast, cost-effective sensor in this area. Herein, we report a fluorescent calix[4]arene derivative (PIMC) for highly selective and sensitive and facile and rapid MET detection based on fluorescence (FL) quenching. The highest FL quenching occurs when PIMC is exposed to MET solution at 400 nm (λ_ex = 340). Owing to the quenching efficacy of MET linearly up to 5.5 × 10⁴ nM was obtained a detection limit of 2.44 nM. Besides, interferences of other pharmaceuticals and ions on probe performance were investigated. The FL probe was successful in MET detection without the assistance of any separation techniques in a pharmaceutical sample (tablet) with an acceptable recovery of 101.3%. The applicability of the current probe as a paper-based sensor to MET detection has been successfully tested. As a result, the proposed probe presents a fast and suitable strategy to sensitive and selective detect MET and proves a good potential for practical applications, especially pharmaceutical preparations.

Decline incidence in upper gastrointestinal bleeding in several recent years: data of the Japan claims database of 13 million accumulated patients

This study was to examine the recent trends in upper gastrointestinal bleeding in Japan using a large-scale real-world database. The incidence of upper gastrointestinal bleeding was evaluated in the Japan Medical Data Center claims database of 13,019,713 patients aged 20 to 74 years with traceability for 3 months from 2009 to 2014. The incidence was compared with peptic ulcers and gastroesophageal reflux disease. The prescription of medications was also evaluated. The incidence of bleeding was 0.137%, 0.121%, 0.113%, 0.106%, 0.099%, and 0.105% during 2009 to 2014 with a time-dependent decline (p<0.001). Peptic ulcers (>10 times higher than the incidence of bleeding) decreased with time (p<0.001), whereas gastroesophageal reflux disease increased (p = 0.006). Upper gastrointestinal bleeding was higher in male patients and older patients (60–74 years old) (p<0.001 respectively). The prescription rate of antithrombotic medications and proton pump inhibitors increased from 2009 to 2014 (p<0.001 respectively). The incidence of upper gastrointestinal bleeding decreased from 2009 to 2014 in this relatively large-scale real-world database in Japan, concomitant with the decrease in peptic ulcers. The decreased incidence might have been due to changes in the disease structure and therapeutic strategies over time.

Sonochemical synthesis of nickel-manganous oxide nanocrumbs decorated partially reduced graphene oxide for efficient electrochemical reduction of metronidazole

In the present work, we report on the synthesis of crump-like nickel manganous oxide nanoparticles decorated partially reduced graphene oxide (NiMnO@pr-GO) nanocomposite through high-intensity ultrasonic bath sonication (ultrasonic frequency = 37 kHz and power = 150 W). The NiMnO@pr-GO nanocomposite modified glassy carbon electrode (GCE) was then employed for the electrochemical reduction of detrimental metronidazole (MNZ). The crystalline phase and formation of the NiMnO@pr-GO nanocomposites were confirmed by X-ray diffraction and other spectroscopic techniques. The cyclic voltammetry results demonstrate that this NiMnO@pr-GO nanocomposite modified GCE has a lower reduction potential and higher catalytic activity towards MNZ than do NiMnO and GO modified GCEs. Under optimized conditions, the fabricated NiMnO@pr-GO electrode can detect metronidazole over a wide linear range with a lower limit of detection of 90 nM. The sensitivity of the sensor was 1.22 µA µM^-1cm^-2 and was found to have excellent selectivity and durability for the detection of MNZ.

Genotype profiles of Helicobacter pylori from gastric biopsies and strains with antimicrobial-induced resistance

BACKGROUND AND AIMS

The genotypic method could significantly shorten the time needed to obtain antibiotic susceptibility data for Helicobacter pylori. The aim of this study was to explore the profile of H. pylori from gastric biopsies and strains with antibiotic-induced resistance.

METHODS

A total of 124 gastric biopsies were used to perform gene sequencing and to perform bacterial culture and susceptibility testing. Seven susceptible strains were selected to develop resistance to clarithromycin, levofloxacin, and metronidazole. Four susceptible strains were selected to transfer candidate mutations. The genotype profiles of these groups were analyzed by sequencing analysis. The antibiotic susceptibility of these strains was detected using the E-test method.

RESULTS

Phenotypic resistance to clarithromycin, levofloxacin, and metronidazole was observed in 35.5%, 40.0%, and 79.8% strains, respectively. Point mutations in 23 S rRNA, gyrA, and rdxA genes were observed in 39.5%, 38.7%, and 86.3% of gastric biopsies, respectively. The A2143G mutation in the 23S rRNA occurs in most clarithromycin-resistant samples. The A2142C point mutation showed a higher efficacy than A2142G and A2143G for inducing clarithromycin resistance. The D91N and N87K mutations in gyrA occurs in most levofloxacin-resistant samples, and double point mutations showed a higher efficacy than single mutations for inducing levofloxacin resistance. Phenotypic resistance and mutations in rdxA lacked consistency.

CONCLUSION

Genotype-based gastric biopsy analysis was reliable for determining clarithromycin and levofloxacin resistance. A2143G in 23S rRNA and N87K/D91N in the gyrA gene occurred in most resistant strains. Mutations in the rdxA gene were not good indicators of metronidazole resistance.

Treatment of Helicobacter pylori infection in children: A systematic review

BACKGROUND

Helicobacter pylori (H. pylori) infection is predominantly acquired in childhood. When indicated, the most accepted treatment for H. pylori eradication in this age group is first-line triple therapy. However, the increasing resistance to clarithromycin and nitroimidazoles has been associated with treatment failure, and thus, alternative treatment regimens have been proposed.

AIM

To perform a systematic review of randomized controlled trials on treatment regimens for H. pylori infection in children.

METHODS

We surveyed relevant articles published in English from 2010 to April 2020 in the PubMed and MEDLINE databases. Keywords included “Helicobacter pylori”/”children or childhood”/”treatment or eradication.” The risk of bias was evaluated according to the Cochrane Handbook of Systematic Reviews for Interventions.

RESULTS

Among the 1144 records identified through the database, 20 articles were selected. Four studies compared the eradication rates of H. pylori infection between standard triple therapies, changing only the main antibiotic used. Seven studies evaluated the effectiveness of standard triple therapy with the addition of probiotics. One study investigated the relationship between the effectiveness in the eradication rates of standard triple therapy and vitamin E levels. Six studies analyzed the eradication rates of sequential therapy.

CONCLUSION

The findings suggest that although standard triple therapy is the most recommended regimen for children by the current guidelines, other therapeutic schemes have shown promising results and may also be recommended for clinical practice in the future.

Proton-pump inhibitor and amoxicillin-based triple therapy containing clarithromycin versus metronidazole for Helicobacter pylori: A meta-analysis

BACKGROUND

Helicobacter pylori (H. pylori) infection is one of the important risk factors of gastric related diseases and antibiotic therapy has become an effective treatment. At present, proton-pump inhibitor and amoxicillin-based triple therapy, including clarithromycin (PAC) and metronidazole (PAM), are two commonly used first-line therapies for H. pylori infection, which has a high incidence and possibly poor prognosis worldwide.

METHODS

A systematic literature review was performed using the databases PubMed, the Cochrane Library, Ovid Medline, Science Direct, Embase, Scopus and Web of Science. Only randomized clinical trials with full texts published were included.

RESULTS

Eighteen studies involving 3264 patients were included. The pooled risk ratios (RR) between the PAC and PAM groups were comparable in the intention-to-treat (ITT) eradication rates (71.0% versus 75.2%, RR = 0.96, p = 0.38) and per-protocol (PP) eradication rates (79.6% versus 80.1%, RR = 1.02, p = 0.65). PAM is highly effective in clarithromycin-resistant cases (70.4% versus 48.2%, RR = 0.65, p = 0.002) and that PAC showed significant efficacy in metronidazole-resistant cases (87.3% versus 58.6%, RR = 1.43, p = 0.0006). In subgroup analysis, when using low-dose PPI, the PAM group showed greater efficacy than the PAC group. Furthermore, we found that PAM showed higher effectiveness in the studies published in recent years, especially for people over 60 years old (RR = 0.80, 95% CI: 0.71-0.89, p < 0.001).

CONCLUSION

In general, both PAC and PAM regimens were effective and comparable in eradicating H. pylori. However, the PAM regimen showed greater efficacy than the PAC regimen in recent years, especially for people over 60 years old.