Prevalence and distribution of Helicobacter pylori cagA and vacA genotypes in the Moroccan population with gastric disease. Eur J Clin Microbiol Infect Dis. 2012;31:1775-1781. [PMID: 22160824 DOI: 10.1007/s10096-011-1501-x]

Global incidence and prevalence of gastritis and duodenitis from 1990 to 2019: A systematic analysis for the Global Burden of Disease Study 2019

BACKGROUND AND AIM

Gastritis and duodenitis, prevalent diseases of the digestive system, impose a significant global burden. This study aimed to examine their incidence and prevalence patterns worldwide, including changes over the past 30 years.

METHODS

The age-standardized incidence rate (ASIR) and age-standardized prevalence rate (ASPR) of gastritis and duodenitis, stratified by age, sex, geographical region, and sociodemographic index (SDI), were obtained from the Global Burden of Disease 2019. The dynamic trends were captured by calculating the average annual percentage changes (AAPC).

RESULTS

In 2019, the global ASIR and ASPR of gastritis and duodenitis were 379.88/100 000 (95% uncertainty interval [UI]: 312.42/100 000-448.12/100 000) and 518.11/100 000 (95% UI: 420.62/100 000-631.66/100 000), respectively. The highest rates were observed among the 50-69 age group (ASIR: 856.48/100 000; ASPR: 1158.04/100 000) and in low SDI regions (ASIR: 443.33/100 000; ASPR: 631.22/100 000). From 1990 to 2019, there was a significant decrease in global ASIR (AAPC = -0.34%, 95% confidence interval [CI]: -0.36% to -0.31%) and ASPR (AAPC = -0.34%, 95% CI: -0.37% to -0.31%) of gastritis and duodenitis. However, ASIR (AAPC = 0.47%, 95% CI: 0.42%-0.52%) and ASPR (AAPC = 0.51%, 95% CI: 0.47%-0.52%) of gastritis and duodenitis experienced a significant increase in low SDI regions.

CONCLUSIONS

Despite a significant decrease in the global incidence and prevalence of gastritis and duodenitis, these conditions continue to impose a burden on individuals aged 50-69 years and low SDI regions. Targeted interventions for those specific populations and regions are necessary.

Is There a Real Relationship between the Presence of Helicobacter pylori in Dental Plaque and Gastric Infection? A Genotyping and Restriction Fragment Length Polymorphism Study on Patient Specimens with Dyspepsia in Southwest Iran

Background

The oral cavity can act as an extra gastric reservoir for H. pylori, and the presence of the bacteria in the oral cavity is associated with a higher risk of dental caries development. This study aimed to determine the genotype and evaluate the association between the presence of H. pylori in dental plaque and gastric biopsy specimens in dyspeptic patients in Ahvaz, Southwest Iran.

Methods

In this study, 106 patients with recruited dyspeptic complaints were selected, and from each patient, two gastric antral biopsy specimens and two dental plagues were examined. The presence of H. pylori was identified by the rapid urease test (RUT) and the amplification of ureAB and 16S rRNA genes. Also, to verify a hypothetical mouth-to-stomach infection route, the enzymatic digestions of three genes of cagA, vacA, and ureAB in H. pylori strains isolated from dental plaques and stomach samples were compared for each same case.

Results

H. pylori was found in the stomach of 52.8% (56/106) and the dental plaques of 17.9% (19/106) of the studied cases. On the other hand, H. pylori was recognized in the stomach of all 19 cases with oral colonization. Following a combination of restriction fragment lengths 21 polymorphism (RFLP) patterns of these three known genes on stomach and dental plague samples, 14 and 11 unique patterns were seen, respectively. However, for all H. pylori-positive cases (19), the comparison of RLFP patterns of these genes in dental plaque and gastric biopsy specimens was different for the same case.

Conclusions

In this study, it seems that there is no significant association between the presence of H. pylori in dental plaque and the stomach of the same case.

Moroccan Children With Helicobacter pylori Infection: Demographics, Clinical Features, and Histological Findings

BACKGROUND

Infesting nearly half of the world's population, Helicobacter pylori is thought to cause peptic ulcers and gastric adenocarcinoma. Several studies have examined the association between H. pylori and socioeconomic, clinical, and histological factors in pediatric populations. Similarly, this study aimed to describe the characteristics of H. pylori infection in Moroccan children.

METHODS

Patients aged 1-17 years who underwent upper gastrointestinal endoscopy over a period of two years from January 2019 to January 2021 were included in this study. Gastric biopsies from the antrum and corpus of the stomach were collected. Detection of H. pylori infection was confirmed by Giemsa stain. Demographic data and clinical and endoscopic characteristics were collected and histopathological findings with gastritis scoring were recorded according to the Sydney System.

RESULTS

In 213 children, 95 (45%) were found to be infected with H. pylori, and the infection rates increased as the children aged. While no significant relationship between the infection of H. pylori and all symptoms was founded, a significant association was found in nodular gastritis (p<0.05), and 98% of the infected children had chronic inflammation, which was active in 22% and atrophic in 47%. The atrophy and activity were absent or mild, and the inflammation was mild to moderate.

CONCLUSION

According to this study, nodular gastritis and nonspecific symptoms were related to H. pylori infection in Moroccan children. In addition, the association between this disease and gastric atrophy in our study needs the monitoring of the mucosa of Moroccan children with gastritis and identifying factors that may contribute to gastric cancer.

Gastric IL-1β, IL-8, and IL-17A expression in Moroccan patients infected with Helicobacter pylori may be a predictive signature of severe pathological stages

INTRODUCTION

Helicobacter pylori induces acute gastritis that can progress to serious diseases such as gastric cancer. H. pylori interacts with host cells within the gastric mucosa, resulting in activation of multiple innate immune signalling pathways, leading to pro-inflammatory cytokines production and immune cells recruitment. Various studies have shown that there are ethnic- and population-related differences in the expression of these cytokines. Although the H. pylori infection is a major public health problem in Morocco, to our knowledge, no study has been carried out in gastric cytokine expression from H. pylori-infected Moroccan patients. Thus we aimed to (i) determine the IL-1β, IL-8 and IL-17A gene expression in gastric biopsies from Moroccan patients infected with H. pylori, and (ii) to determine the cytokine signature of each pathological stages associated with this infection.

MATERIAL AND METHODS

71 patients with epigastralgic pain were included in this study. The H. pylori detection on gastric biopsies was performed by histopathological and PCR analysis. The IL-1β, IL-8 and IL-17A mRNA expression in the antrun and fundus biopsies was performed by RT-qPCR.

RESULTS

The histopathological and PCR analyses revealed that 87.32% of the patients were infected with H. pylori. IL-1β mRNA expression was significantly lower in the antral mucosa of H. pylori-infected patients (p = 0.0038) than in the uninfected while there was no significant difference in the expression of IL-8 and IL-17A mRNA. The expression of the three cytokines was higher in the fundic mucosa of H. pylori-infected patients than in the uninfected patients, but only IL-8 and IL-17A expression reached statistical significance (p = 0.042 and p = 0.0179 respectively). Furthermore, the multivariate predictive analysis highlighted a cytokine signature that may predict metaplasia during the infection progression that involves a specific down-regulation of IL17A and an up-regulation of IL1β in antral and fundic metaplasia respectively.

Infections with Helicobacter pylori and challenges encountered in Africa

Helicobacter pylori (H. pylori) is the causative agent of gastritis, peptic ulcer disease, mucosa associated lymphoid tissue lymphoma and gastric cancer (GC). While this bacterium infects 50% of the world’s population, in Africa its prevalence reach as high as 80% as the infection is acquired during childhood. Risk factors for H. pylori acquisition have been reported to be mainly due to overcrowding, to have infected siblings or parent and to unsafe water sources. Despite this high H. pylori prevalence there still does not exist an African guideline, equivalent to the Maastricht V/Florence Consensus Report of the European Helicobacter and Microbiota Study Group for the management of this infection. In this continent, although there is a paucity of epidemiologic data, a contrast between the high prevalence of H. pylori infection and the low incidence of GC has been reported. This phenomenon is the so-called “African Enigma” and it has been hypothesized that it could be explained by environmental, dietary and genetic factors. A heterogeneity of data both on diagnosis and on therapy have been published. In this context, it is evident that in several African countries the increasing rate of bacterial resistance, mainly to metronidazole and clarithromycin, requires continental guidelines to recommend the appropriate management of H. pylori. The aim of this manuscript is to review current literature on H. pylori infection in Africa, in terms of prevalence, risk factors, impact on human health, treatment and challenges encountered so as to proffer possible solutions to reduce H. pylori transmission in this continent.

Virulence factor genotyping of Helicobacter pylori isolated from Costa Rican dyspeptic patients

BACKGROUND AND AIMS

Costa Rica is one of the countries with the highest incidence and mortality rates for gastric cancer. Helicobacter pylori infection rates are high in the whole country. We have previously shown that H. pylori CagA+ is significantly associated with atrophic gastritis (AG) of the antrum in a dyspeptic population. The aim of this work is to determine if other H. pylori virulence factors (vacA, dupA, oipA, iceA and babA2) are associated with atrophic gastritis (AG) or duodenal ulcer (DU).

METHODS

The presence of virulence genes in Costa Rican H. pylori isolates was analyzed by PCR in 151 cultured strains from patients with dyspeptic symptoms. Endoscopic and histopathological diagnoses were available. Odds-ratio and 95% confidence intervals for AG patients vs. non-atrophic gastritis (NAG) or DU patients vs. no duodenal ulcer (NDU) patients were calculated.

RESULTS

Amongst the studied isolates, 82% had the cagA⁺, 76.2% had the vacA s1m1, 97.0% had the oipA⁺, 21.0% had the icea1, 79.0% had the iceA2, 44.0% had the babA2⁺ and 76.0% the dupA⁺ genotypes. Infection with H pylori cagA⁺, dupA⁺, oipA⁺, iceA, babA2⁺, and vacA s1m1 genotypes was not associated with AG risk. The frequency of the dupA gene was 78.7 and 60.9% in isolates from patients with NDU and DU, respectively, and its presence was significantly associated with decreased risk of duodenal ulcer [odds-ratio: 0.33, p = 0.024, confidence interval 95% (0.11-0.85)].

CONCLUSION

H. pylori dupA genotype is inversely associated with DU risk in this population.

A review of the infection-associated cancers in North African countries

Cancer is typically classified as a leading non-communicable disease; however, infectious agents, such as Helicobacter pylori (H. pylori), hepatitis B virus (HBV), hepatitis C virus (HCV) and human papilloma virus (HPV), contribute significantly to the pathogenesis of various cancers. Less developed countries, including countries of the North African (NA) region, endure the highest burden of infection-related cancers. The five most common infection-associated cancers in NA in order of incidence are bladder cancer, cervical cancer, liver cancer, stomach cancer, and nasopharyngeal carcinoma. This review aims to outline the epidemiologic pattern of infection-associated cancers in five NA countries (namely: Morocco, Algeria, Tunisia, Libya and Egypt) highlighting the similarities and differences across the region. The present study employed an initial literature review of peer-reviewed articles selected from PubMed, ScienceDirect and World Health Organization (WHO) databases based on key word searches without restriction on publication dates. Original research articles and reports written in French, as well as data from institutional reports and regional meeting abstracts were also included in this extensive review. Egypt, Libya, Tunisia, Algeria and Morocco were selected to be the focus of this review.

Correlation of Helicobacter pylori genotypes with gastric histopathology in the central region of a South-European country

BACKGROUND

Outcome of Helicobacter pylori (H. pylori) infection results from interaction of multiple variables including host, environmental and bacterial-associated virulence factors.

AIM

This study aimed to investigate the correlation of cagA, cagE, vacA, iceA and babA2 genotypes with gastric histopathology and disease phenotype in the central region of a South-European country.

METHODS

This prospective study involved 148 infected patients (110 female; mean age 43.5 ± 13.4 years) submitted to endoscopy with corpus and antrum biopsies. H. pylori was cultured and DNA extracted from the isolates. Genotypes were determined by PCR. Histopathological features were graded according to the updated Sydney system and OLGA/OLGIM classification. Only patients with single H. pylori genotypes and complete histopathological results were included.

RESULTS

Antrum samples presented higher degrees of atrophy, intestinal metaplasia, chronic inflammation and neutrophil activity. Genotype distribution was as follows: cagA-31.8 %; cagE-45.9 %; vacA s1a-24.3 %; vacA s1b-19.6 %; vacA s1c-0.7 %; vacA s2-55.4 %; vacA m1-20.9 %; vacA m2-79.1 %; vacA s1m1-18.9 %; vacA s1m2-25.7 %; vacA s2m1-2 %; vacA s2m2-53.4 %; iceA1-33.8 %; iceA2-66.2 %; babA2-12.2 %. CagA genotype was significantly associated with higher degrees of intestinal metaplasia, neutrophil activity, chronic inflammation and OLGIM stages. BabA2 was linked with higher H. pylori density. Strains with vacA s1m1 or vacA s1m1 + cagA positive genotypes had a significant association with peptic ulcer and vacA s2m2 with iron-deficient anemia.

CONCLUSIONS

cagA, vacA s1m1 and babA2 genotypes are relatively rare in the central region of Portugal. cagA-positive strains are correlated with more severe histopathological modifications. This gene is commonly associated with vacA s1m1, and such isolates are frequently found in patients with peptic ulcer.

Helicobacter pylori genotypes associated with gastric histo-pathological damages in a Moroccan population

H. pylori persistent infection induces chronic gastritis and is associated with peptic ulcer disease and gastric carcinoma development. The severity of these diseases is related to human's genetic diversity, H. pylori genetic variability and environmental factors. To identify the prevalence of histo-pathological damages caused by H. pylori infection in Moroccan population, and to determine their association to H. pylori genotypes, a prospective study has been conducted during 3 years on patients attending the gastroenterology department of Hassan II University Hospital (CHU) of Fez, Morocco. A total of 801 Moroccan adults' patients were recruited; H. pylori was diagnosed and genotyped by PCR in biopsy specimens and histological exam was performed. We found a high rate of glandular atrophy. Chronic inflammation, neutrophil activity and glandular atrophy showed statistically significant association with H. pylori infection. However, intestinal metaplasia was inversely associated to this infection and no association was observed with gastric cancer cases. A statistically significant association was found between intestinal metaplasia and vacAs1 and vac Am1 genotypes in patients aged 50 years and more but not in younger. This last genotype is also associated to gastric cancer. In this study, gastric cancer showed no significant association with H. pylori. Further studies are warranted to determine the role of other etiological agents such as Epstein-Barr virus, human papillomavirus and possibly environmental and dietetic factors in the occurrence of this pathology.

Polymorphism in the Helicobacter pylori CagA and VacA toxins and disease

Half of the world's population is infected with Helicobacter pylori and approximately 20% of infected individuals develop overt clinical disease such as ulcers and stomach cancer. Paradoxically, despite its classification as a class I carcinogen, H. pylori has been shown to be protective against development of asthma, allergy, and esophageal disease. Given these conflicting roles for H. pylori, researchers are attempting to define the environmental, host, and pathogen interactions that ultimately result in severe disease in some individuals. From the bacterial perspective, the toxins, CagA and VacA, have each been shown to be polymorphic and to contribute to disease in an allele-dependent manner. Based on the notable advances that have recently been made in the CagA field, herein we review recent studies that have begun to shed light on the role of CagA polymorphism in H. pylori disease. Moreover, we discuss the potential interaction of CagA and VacA as a mediator of gastric disease.