Epidemiology of Helicobacter pylori among multiracial community in Northern Peninsular, Malaysia: effect of age across race and gender. ASIAN PAC J TROP MED. 2011;4:72-75. [PMID: 21771421 DOI: 10.1016/s1995-7645(11)60037-0]

Clinical Factors Implicated in Antibiotic Resistance in Helicobacter pylori Patients

Helicobacter pylori is a common gastric pathogen associated with multiple clinical syndromes, including cancer. Eradication rates of H. pylori remain suboptimal despite the progress made in the past few decades in improving treatment strategies. The low eradication rates are mainly driven by antibiotic resistance of H. pylori. Non-invasive molecular testing to identify patients with antibiotic-resistant H. pylori represents a promising therapeutic avenue, however this technology currently remains limited by availability, costs, and lack of robust validation. Moreover, there is insufficient evidence to demonstrate that resistance-testing-based treatment approaches are superior to appropriately designed empiric strategies. Consensus guidelines recommend use of proven locally effective regimens; however, eradication data are inconsistently generated in several regions of the world. In this review, we describe several clinical factors associated with increased rates of antibiotic resistant H. pylori, including history of previous antibiotic exposure, increasing age, female gender, ethnicity/race, extent of alcohol use, and non-ulcer dyspepsia. Assessment of these factors may aid the clinician in choosing the most appropriate empiric treatment strategy for each patient. Future study should aim to identify locally effective therapies and further explore the clinical factors associated with antibiotic resistance.

Helicobacter pylori in the Indonesian Malay's descendants might be imported from other ethnicities

BACKGROUND

Even though the incidence of H. pylori infection among Malays in the Malay Peninsula is low, we observed a high H. pylori prevalence in Sumatra, which is the main residence of Indonesian Malays. H. pylori prevalence among Indonesian Malay descendants was investigated.

RESULTS

Using a combination of five tests, 232 recruited participants were tested for H- pylori and participants were considered positive if at least one test positive. The results showed that the overall H. pylori prevalence was 17.2%. Participants were then categorized into Malay (Aceh, Malay, and Minang), Java (Javanese and Sundanese), Nias, and Bataknese groups. The prevalence of H. pylori was very low among the Malay group (2.8%) and no H. pylori was observed among the Aceh. Similarly, no H. pylori was observed among the Java group. However, the prevalence of H. pylori was high among the Bataknese (52.2%) and moderate among the Nias (6.1%). Multilocus sequence typing showed that H. pylori in Indonesian Malays classified as hpEastAsia with a subpopulation of hspMaori, suggesting that the isolated H. pylori were not a specific Malays H. pylori.

CONCLUSIONS

Even though the ethnic groups live together as a community, we observed an extremely low H. pylori infection rate among Indonesian Malay descendants with no specific Indonesian Malay H. pylori. The results suggest that H. pylori was not originally among these groups and H. pylori was imported from other ethnic groups.

Association between Toll-like receptor gene polymorphisms and risk of Helicobacter pylori infection: A protocol for systematic review and meta-analysis

BACKGROUND

There were many case-control studies performed the association between TLRs gene polymorphisms and the correlation of Helicobactor pylori infection, these results were inconformity. Therefore, a comprehensive meta-analysis was performed to evaluate the TLRs gene polymorphism and susceptibility to H. pylori infection.

METHODS

Eligible studies were searched from PubMed, EMBASE, Web of science, Cochrane library, CNKI, CBM, Wan Fang Database and VIP Database, all the databases were searched from inception to December 2020. OR with the corresponding 95% CI were presented as associations between certain TLR gene polymorphism and the risk of H. pylori infection, all the included data will be analyzed with the software of Review Manager 5.2 and STATA 14.2.

RESULTS

This study will provide a high-quality evidence to find the TLR gene polymorphisms with H. pylori infection susceptibility.

CONCLUSION

This study will explore which TLR genotype increase the risk of H. pylori infection.

Molecular characterization and prevalence of antibiotic resistance in Helicobacter pylori isolates in Kuala Lumpur, Malaysia

Aims and objectives

Helicobacter pylori has been classified as high priority pathogen by the WHO in 2017. The emergence of antibiotic-resistant strains is one of the main causes of treatment failure in H. pylori infection. This study determined and characterized primary and secondary resistances in H. pylori in Malaysia.

Materials and methods

Gastric biopsies from antrum (n=288) and corpus (n=283) were obtained from 288 patients who underwent endoscopy at Universiti Kebangsaan Malaysia Medical Center (UKMMC), Kuala Lumpur, Malaysia. Antibiotic susceptibility to six classes of antibiotics was determined by the E-test. Mutations conferring in resistance in functional genes were identified by PCR and sequencing.

Results

Overall resistance rates to metronidazole, clarithromycin and levofloxacin were 59.3% (35/59), 35.6% (21/59) and 25.4% (15/59), respectively. Secondary isolates showed significantly higher resistance rates to clarithromycin compared to the primary isolates. Mixed infection with susceptible and resistant isolates was observed in 16.2% (6/37) of cases, of which 83.3% (n=5) had infection with the same strain. 41% (18/44) of isolates were resistant to more than one class of antibiotics of which 50% (9/18) were multidrug-resistant, two being primary and seven being secondary isolates. Mutations in rdxA, 23S rRNA and gyrA genes were associated with resistance to metronidazole, clarithromycin and levofloxacin, respectively.

Conclusion

The high level of resistance to metronidazole, clarithromycin and levofloxacin seen in H. pylori isolates in our setting warrants the need for continuous surveillance and highlights caution in use of antibiotics generally used as first-line therapy in H. pylori eradication regimen.

Assessment of Risk and Sero-Prevalence of Helicobacter pylori Colonization among Remote Orang Asli Tribes in Peninsula Malaysia

The epidemiology of Helicobacter pylori (H. pylori) infection is related to human poverty with marked differences between developing and developed countries. Socioeconomic factors and living standards are the main determinants of the age-dependent acquisition rate of H. pylori, and consequently its prevalence. The aim of this study was to assess the risk and sero-prevalence of H. pylori colonization among Orang Asli in Peninsula Malaysia. This cross-sectional study was conducted on Orang Asli subjects in seven isolated settlements spanning across all three major tribes (Negrito, Proto Malay and Senoi) in Malaysia. Socio-demographic characteristics of the subjects were obtained through interview. Subjects were tested for H. pylori colonization based on CagA and whole cell (WC) antigen serological assays. A total of 275 subjects participated in this study. Among these subjects, 115 (44.7%) were H. pylori sero-positive with highest sero-prevalence among Negrito (65.7%). Among subjects who were H. pylori sero-positive, CagA sero positivity was also significantly higher among Negrito. The highest proportion of respondents reported to be H. pylori sero-positive was from age group 30 years old and below (57.9%), males (56.2%), Negrito (48.6%) and live in bamboo house (92.3%). The highest proportion of respondents reported to be CagA sero-positive was from age group 30 years old and below (41.4%), males (35.6%) and Negrito (48.6%). The results of this study demonstrate that H. pylori colonization can be related to age, gender, tribes and house materials and CagA sero-positive stain closely associated with age, gender and tribes.

Correlation of Helicobacter pylori and interleukin-8 mRNA expression in high risk gastric cancer population prediction

AIM: To evaluate (1) the association of the Helicobacter pylori (H. pylori) test and interleukin-8 (IL-8) mRNA expression alone and the severity of gastric cancer (GC); (2) the association of both tests were added to patients' characteristics to identifli Thai suspected patients of gastric cancer who would receive the most benefit; and (3) diagnostic value of levels of IL-8 mRNA expression for gastric cancer.

METHODS: A cross-sectional analytical study was completed with 220 patients with 86 GC patients who underwent endoscopy with gastric surgery divided into non-metastasis and metastasis groups, and 134 patients with benign lesions who underwent endoscopic examination, at the Gastrointestinal Surgery and Endoscopy Unit, Chiang Mai University Hospital between 2006 and 2010. Of 220 patients, 86 cases of diagnosed gastric adenocarcinoma were in an advanced stage and 134 cases were non-cancer patients.

RESULTS: The IL-8 mRNA expression showed predominant association with advanced GC when compared to H. pylori infection alone [OR (95%CI); 0.86 (0.49-1.53) vs 5.44 (3.08-9.62)] when including the patients’ characteristics the highest of the area under the receiver operating characteristic curves (AuROC) of the model were males older than 40 years of age [AuROC (95%CI); 0.81 (0.75-0.86)]. However, preliminary testing for diagnostic indices of four cut-off points of IL-8 mRNA expression to predict the severity of GC cases found an increasing suboptimal trend from the likelihood ratio of positive to differentiate the severity in the GC group. The IL-8 mRNA expression showed a predominant association with GC when compared to H. pylori infection, especially in males older than 40 years of age who may benefit most from this test.

CONCLUSION: The future research of IL-8 mRNA expression to predict severity in the gastric cancer group should be warranted.

Reciprocal impact of host factors and Helicobacter pylori genotypes on gastric diseases

AIM: To assess the impact of Helicobacter pylori (H. pylori) genotypes and patient age and sex on the development of gastric diseases.

METHODS: H. pylori-infected patients (n = 233) referred to the endoscopy unit at Tehran University of Medical Sciences (Tehran, Iran) were diagnosed with chronic gastritis (CG), gastric ulcer (GU), or duodenal ulcer (DU). Brucella blood agar was used for biopsy cultures and H. pylori isolation under microaerobic conditions. H. pylori isolates were confirmed with biochemical tests and through amplification of the 16S rRNA gene. DNA was extracted from fresh cultures of the H. pylori isolates and used for amplification of vacA alleles and the cagA gene. Statistical analysis was performed to determine the association between H. pylori genotypes, age (< 40 years vs > 40 years) and sex of the patient, and gastric diseases.

RESULTS: CG was the most prevalent gastric disease (113/233; 48.5%), compared to GU (64/233; 27.5%) and DU (56/233; 24%). More patients were male, and gastric diseases were more frequent in patients > 40 years (P < 0.05). The percentage of CG and GU patients that were male and female did not show a significant difference; however DU was more common in males (P < 0.05). Interestingly, a diagnosis of CG in patients > 40 years was more common in females (18.5%) than males (11.6%) (P = 0.05), whereas a diagnosis of GU or DU in patients > 40 years was more frequent in males (14.6% vs 10.7% and 12.4% vs 4.3%, respectively). Overall, genotyping of the H. pylori isolates revealed that the vacA s1 (82%), vacA m2 (70%), and cagA⁺ (72.5%) alleles were more frequent than vacA s2 (18%), vacA m1 (29.2%), and cagA^- (all P < 0.05). The vacA s1m2cagA⁺ genotype was the most prevalent within the three disease groups. vacA s1m2 frequency was 56.2% with a similar occurrence in all diagnoses, while vacA s1m1 appeared more often in DU patients (33.9%). A genotype of vacA s2m2 occurred in 15% of isolates and was more common in CG patients (21.2%); vacA s2m1 was the least common genotype (3%). The vacA s1 allele was found to be a risk factor for DU, vacA s2 for CG, and vacA s1 and vacA s2 for GU (all P < 0.05). The vacA s2m2 genotype was associated with the development of CG and GU compared to DU (P < 0.05). No correlation was found between vacA m or cagA and gastric diseases.

CONCLUSION: The outcome of H. pylori infection is the result of interaction between bacterial genotypes and the age and sex of infected individuals.

Helicobacter Pylori Infection in Waste Pickers: A Case Control Seroprevalence Study

Background

The epidemiology of Helicobacter pylori (H. pylori) infection in waste pickers had not been previously studied. This study aims to determine the association of H. pylori seropositivity and waste picking activity; and to determine socio-demographic, clinical, work, and behavioral characteristics associated with H. pylori seropositivity in waste pickers.

Methods

Through a case-control study design, we examined 90 waste pickers and 90 age- and gender-matched control subjects for the presence of anti-H. pylori IgG antibodies using enzyme-linked immunoassays. Seroprevalence association with socio-demographic, clinical, work and behavioral characteristics of the waste pickers were also investigated.

Results

Antibodies to H. pylori were found in 60 (66.7%) of the 90 waste pickers and in 51 (56.7%) of the 90 controls (P = 0.16). Stratification by age showed that waste pickers aged 14 -30 years old had significantly higher frequency of H. pylori infection than controls of the same age group (56.5% versus 35.6%, respectively; P = 0.04). The seroprevalence of H. pylori infection was not influenced by gender, age, educational level, socioeconomic status, residence, or housing conditions of waste pickers. The presence of underlying diseases and the frequency of gastritis were similar among H. pylori positive and H. pylori negative waste pickers. Logistic regression analysis showed that the duration (years) in the waste picking activity was positively associated with H. pylori exposure (OR = 2.76; 95% CI: 1.22 - 6.25; P = 0.01). In contrast, consumption of alcohol was negatively associated with H. pylori exposure (OR = 0.27; 95% CI: 0.09 - 0.78; P = 0.01). Other work or behavioral characteristics of waste pickers including washing hands before eating, eating from the garbage, animal contacts, consumption of unpasteurized milk, unwashed raw vegetables, fruits, or untreated water, and contact with soil were not associated with H. pylori exposure.

Conclusions

This is the first report on the seroprevalence of H. pylori infection among waste pickers and the factors contributing to such exposure. Results warrant for further research on the potential role of contact with garbage for H. pylori infection.

Seroepidemiology of Helicobacter pylori infection in a Mennonite community in Durango State, Mexico

BACKGROUND

The epidemiology of Helicobacter pylori infection among Mennonites (an ethnic group of German descent living in rural communities in Mexico) has not been previously studied.

MATERIALS AND METHODS

The prevalence of anti-H. pylori IgG antibodies was examined in 152 Mennonite individuals in Durango State, Mexico, using enzyme-linked immunoassays. Seroprevalence association with sociodemographic, clinical, and behavioral characteristics of the Mennonite community was also investigated.

RESULTS

In total, 77 (50.7%) of the 152 Mennonite participants (mean age, 38.4 ± 15.5 years) had H. pylori IgG antibodies, 35 (45.4%) of whom had H. pylori IgG antibody levels higher than 100 U/mL. Males and females had comparable seroprevalence rates of H. pylori and H. pylori IgG antibody levels. On the other hand, seroprevalence of H. pylori increased significantly with age and was significantly higher among women with history of deliveries and abortions than among those with no such obstetric characteristics. Logistic regression analysis of behavioral characteristics showed that H. pylori infection was associated with a low frequency of eating at restaurants and at fast food outlets (up to 10 times/year) (OR = 2.77; 95% CI: 1.28-5.98; p = .009), and eating meat (up to 3 days/week) (OR = 2.84; 95% CI: 1.36-5.91; p = .005).

CONCLUSIONS

This is the first report on the seroprevalence of H. pylori among Mennonites, factors contributing to such infection, and the association of H. pylori infection with abortions and low frequencies of eating out of home and meat. Further research should be conducted on this topic.

Seroepidemiology of Helicobacter pylori Infection in Tepehuanos Aged 15 Years and Older in Durango, Mexico

This study aimed to determine the seroepidemiology of Helicobacter pylori infection in Tepehuanos (an indigenous ethnic group living in rural Mexico). The prevalence of anti-Helicobacter pylori IgG antibodies was examined in 156 Tepehuanos in Durango State, Mexico, using an enzyme-linked immunoassay. In addition, sociodemographic, clinical, and behavioral characteristics of Tepehuanos associated with seropositivity were investigated. In total, 103 (66%) of the 156 participants (mean age 31.03  ±  16.71 years) had Helicobacter pylori IgG antibodies. Fifty-four (52.4%) of the 103 seropositive individuals had Helicobacter pylori IgG antibody levels higher than 100 U/mL. Males and females had comparable seroprevalence of Helicobacter pylori infection and Helicobacter pylori IgG antibody levels. The seroprevalence was significantly higher in women with pregnancies than those without this obstetric characteristic. Logistic regression showed that Helicobacter pylori infection was positively associated with low education (OR = 3.37; 95% CI: 1.13-10.00; P = 0.02) and laborer occupation (OR = 2.71; 95% CI: 1.14-6.42; P = 0.02). This is the first report of seroprevalence and contributing factors for Helicobacter pylori infection in Tepehuanos and of the association of Helicobacter pylori infection with laborer occupation. Results warrants further research.

Different risk factors influence peptic ulcer disease development in a Brazilian population

AIM: To investigate age, sex, histopathology and Helicobacter pylori (H. pylori) status, as risk factors for gastroduodenal disease outcome in Brazilian dyspeptic patients.

METHODS: From all 1466 consecutive dyspeptic patients submitted to upper gastroscopy at Hospital das Clinicas of Marilia, antral biopsy specimens were obtained and subjected to histopathology and H. pylori diagnosis. All patients presenting chronic gastritis (CG) and peptic ulcer (PU) disease localized in the stomach, gastric ulcer (GU) and/or duodenal ulcer (DU) were included in the study. Gastric biopsies (n = 668) positive for H. pylori by rapid urease test were investigated for vacuolating cytotoxin A (vacA) medium (m) region mosaicism by polymerase chain reaction. Logistic regression analysis was performed to verify the association of age, sex, histopathologic alterations, H. pylori diagnosis and vacA m region mosaicism with the incidence of DU, GU and CG in patients.

RESULTS: Of 1466 patients submitted to endoscopy, 1060 (72.3%) presented CG [male/female = 506/554; mean age (year) ± SD = 51.2 ± 17.81], 88 (6.0%) presented DU [male/female = 54/34; mean age (year) ± SD = 51.4 ± 17.14], and 75 (5.1%) presented GU [male/female = 54/21; mean age (year) ± SD = 51.3 ± 17.12] and were included in the comparative analysis. Sex and age showed no detectable effect on CG incidence (overall χ² = 2.1, P = 0.3423). Sex [Odds ratios (OR) = 1.8631, P = 0.0058] but not age (OR = 0.9929, P = 0.2699) was associated with DU and both parameters had a highly significant effect on GU (overall χ² = 30.5, P < 0.0001). The histopathological results showed a significant contribution of ageing for both atrophy (OR = 1.0297, P < 0.0001) and intestinal metaplasia (OR = 1.0520, P < 0.0001). Presence of H. pylori was significantly associated with decreasing age (OR = 0.9827, P < 0.0001) and with the incidence of DU (OR = 3.6077, P < 0.0001). The prevalence of m1 in DU was statistically significant (OR = 2.3563, P = 0.0018) but not in CG (OR = 2.678, P = 0.0863) and GU (OR = 1.520, P= 0.2863).

CONCLUSION: In our population, male gender was a risk factor for PU; ageing for GU, atrophy and metaplasia; and H. pylori of vacA m1 genotype for DU.