Epidemiology of Helicobacter pylori infection among the healthy population in Iran and countries of the Eastern Mediterranean Region: A systematic review of prevalence and risk factors

Prevalence and Associated Symptoms of Helicobacter pylori Infection among Schoolchildren in Kassala State, East of Sudan

This study aimed to determine the prevalence of H. pylori infections among schoolchildren and investigate the associations between H. pylori seropositivity and existence of gastrointestinal symptoms. Methods. A prospective cross-sectional study was conducted during a period from January to December 2012 at Kassala state, east of Sudan. Schoolchildren from different primary schools were enrolled in the study. Sociodemographic characteristics and gastrointestinal symptoms were recorded from each child. A rapid immunochromatographic test was performed for the detection of H. pylori IgG antibodies. Data on patient demographic characteristics, clinical diagnosis, and findings of H. pylori infection were analyzed by simple descriptive statistics. Results. Among 431 schoolchildren, H. pylori seropositivity was found to be 21.8%. The majority of children (79; 84%) had BMI below the normal range. The most frequent symptoms associated with H. pylori infections were nausea (25.5%), followed by gastric pain (24.5%) and heart pain (20.2%). There were statistically significant differences in H. pylori seropositivity between boys and girls (p = 0.003). Conclusions. The prevalence of H. pylori infection among schoolchildren in Kassala city has been documented. Although the majority of the disease was associated with several gastrointestinal symptoms, the role of infection in the etiology of abdominal symptoms needs further investigations.

Exploring current status of Helicobacter pylori infection in different age groups of patients with dyspepsia

Recent data from Asian countries including India has shown a significant decline in the frequency of peptic ulcer disease (PUD) compared to the past. H. pylori is considered the most important risk factor for PUD, and we aimed to explore the current frequency of H. pylori infection in different age groups of patients with dyspepsia. Patients >15 years of age with dyspeptic symptoms were prospectively recruited in this study from 2010 to 2014 after obtaining informed consent. Patients were divided into three age groups: 15-30 years, 31-50 years, and >50 years, and the minimum sample size required in the three groups with a power of 90% was 259, 256, and 188, respectively. All patients underwent upper gastrointestinal endoscopy; rapid urease test was done on gastric mucosal biopsy to detect H. pylori. The clinical, demographic features and socioeconomic status were recorded. The institute review board approved the study. We included 1000 patients with dyspepsia during the study period. Their mean age was 40.0+13.3 years, and 69.3% were males. Infection with H. pylori was detected in 419 (41.9%) patients. Among men, H. pylori was present in 45.7% while the frequency of infection in women was lower at 33.2% (p < 0.001). In the 15-30 years age group (n = 303), the frequency of infection was 42.6% while it was 48.3% in the 31-50 years group (n = 350) and 34.9% in the above 50 years group (n = 347). Male sex was a significant risk factor for H. pylori infection (p < 0.001). H. pylori infection, an important risk factor for PUD, was detected in less than half of the dyspeptic patients in the current study.

Histopathological Changes in Laparoscopic Sleeve Gastrectomy Specimens: Prevalence, Risk Factors, and Value of Routine Histopathologic Examination

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is a common surgical therapeutic option for obese patients, with debate about the value of routine histopathologic examination of LSG specimens. We assessed the following: prevalence of different histopathologic changes in LSG specimens, risk factors associated with premalignant and with frequent histopathologic changes, and whether routine histopathologic examination is warranted for LSG patients with nonsignificant clinical history.

METHODS

Retrospective review of records of all LSG patients operated upon at Hamad General Hospital, Qatar (February 2011-July 2014, n = 1555), was conducted. Risk factors (age, BMI, gender, and Helicobacter pylori) were assessed in relation to specific abnormal histopathologic changes.

RESULTS

Mean age and BMI of our sample were 35.5 years and 46.8, respectively. Females comprised 69.7% of the sample. Normal histopathologic specimens comprised 52% of the sample. The most common histopathologic changes were chronic inactive gastritis (33%), chronic active gastritis (6.8%), follicular gastritis (2.7%), and lymphoid aggregates (2.2%). We observed rare histopathology in 3.3% of the sample [e.g., intestinal metaplasia and gastrointestinal stromal tumor (GIST)]. Older age was associated with GIST and intestinal metaplasia (P = 0.001 for both). Females were associated with chronic active gastritis (P = 0.003). H. pylori infection was associated with follicular gastritis, lymphoid aggregates, GIST, intestinal metaplasia, and chronic active gastritis (P < 0.001 for each).

CONCLUSION

Older age, H. pylori, and female gender are risk factors for several abnormal histopathologic changes. Histopathologic examination of LSG specimens might harbor significant findings; however, routine histopathologic examination of all LSG specimens, particularly in the absence of suggestive clinical symptoms, is questionable. The association between female gender and chronic active gastritis; and the association between H. pylori infection and GIST are both novel findings that have not been previously reported in the published literature.

Helicobacter pylori infection is not associated with failure to thrive: a case control study

Purpose

The long-term impact of Helicobacter pylori infection is complex, and concerns about the need for eradication exist. We conducted this case control study to investigate the association between H. pylori infection and failure to thrive (FTT).

Patients and methods

From January 2009 to December 2011, 53 children with FTT group and matched children with the same sex and age and similar socioeconomic status without FTT (control group) were enrolled. A questionnaire was administered to the parents/guardian, and a ¹³C-urea breath test was performed to detect H. pylori infection.

Results

We found that the total prevalence of H. pylori infection was 29.2% and that there was no association between FTT and H. pylori infection (FTT group: 32%; control group: 26.4%; P=0.67). Short stature was more common in the FTT group and abdominal pain in the control group (FTT group: 37.7%; control group: 11.3%; P=0.003). In a comparison between the H. pylori-positive and -negative groups, abdominal pain (87.1% vs 64%; P=0.032) and the frequency of endoscopy (74.2% vs 32%; P<0.001) were significantly more common in the H. pylori-positive group.

Conclusion

We found that children with H. pylori infection are at an increased risk for abdominal pain and that FTT is not associated with H. pylori infection. The decision for eradication should be evaluated carefully and individualized.

What constitutes an Arabian Helicobacter pylori? Lessons from comparative genomics

BACKGROUND

Helicobacter pylori, the human gastric pathogen, causes a variety of gastric diseases ranging from mild gastritis to gastric cancer. While the studies on H. pylori are dominated by those based on either East Asian or Western strains, information regarding H. pylori strains prevalent in the Middle East remains scarce. Therefore, we carried out whole-genome sequencing and comparative analysis of three H. pylori strains isolated from three native Arab, Kuwaiti patients.

MATERIALS AND METHODS

H. pylori strains were sequenced using Illumina platform. The sequence reads were filtered and draft genomes were assembled and annotated. Various pathogenicity-associated regions and phages present within the genomes were identified. Phylogenetic analysis was carried out to determine the genetic relatedness of Kuwaiti strains to various lineages of H. pylori. The core genome content and virulence-related genes were analyzed to assess the pathogenic potential.

RESULTS

The three genomes clustered along with HpEurope strains in the phylogenetic tree comprising various H. pylori lineages. A total of 1187 genes spread among various functional classes were identified in the core genome analysis. The three genomes possessed a complete cagPAI and also retained most of the known outer membrane proteins as well as virulence-related genes. The cagA gene in all three strains consisted of an AB-C type EPIYA motif.

CONCLUSIONS

The comparative genomic analysis of Kuwaiti H. pylori strains revealed a European ancestry and a high pathogenic potential.

Sero-prevalence of Helicobacter pylori Infection in Neyshabur, Iran, During 2010-2015

BACKGROUNDS & OBJECTIVE

The Helicobacter pylori prevalence has continuously decreased during recent years in Iran. The current study aimed at determining H. pylori prevalence in Neyshabur city, Northeast Iran, during 2010-2015.

METHODS

The current epidemiologic survey was conducted in Neyshabur from 2010 to 2015 to determine the prevalence of H. pylori infection. A total of 11596 participants (3681 male with the mean age of 31.7±6.2 years and 7915 female with mean age of 68.3±4.7 years) were included. The enzyme-linked immunosorbent assay kits for the detection of H. pylori and Stat Fax 3200® Microplate Reader (USA) with a sensitivity of 95% and specificity of 98% were used. Titers above 12 units were considered positive for IgG, IgA, and IgM (negative <8, equivocal 8 to 12, and positive >12 U). The Chi-square t test and F test were used to analyze data.

RESULTS AND CONCLUSION

The overall IgA, IgG, and IgM seropositive samples among the study participants were 852 (7.2%), 9000 (72.8%), and 1256 (5.2%), respectively. The IgA seropositivity was significantly high among the age group above 51 years, compared with the other age groups. Moreover, the IgG and IgM seropositivity were significantly high among the age groups 41 to 50 and 31 to 40 years respectively, compared with the other age groups. There was no significant difference between male and female cases regarding IgA and IgG seropositive samples, but IgM level was significantly higher among females, compared with that of the male cases. Furthermore, there was no significant alteration in IgA, IgG, and IgM seropositivity during 2010-2014 in Neyshabur. The prevalence of H. pylori in Neyshabur was high in the healthy population. Furthermore, the H. pylori prevalence did not change from 2010 to 2014 in the studied city. Effective approaches to improve health, educational, and socioeconomic status should be implemented to minimize and control H. pylori infection.

IL-17A Levels in the Sera of Patients with Gastric Cancer Show Limited Elevation

BACKGROUND

Inflammation plays a major role in the development and progression of gastric and other gastrointestinal tumors. The IL-17 family of cytokines has been under investigation as targets of immunotherapy.

MATERIALS AND METHODS

We investigated the levels of IL-17A inflammatory cytokine in the sera of 57 patients with gastric cancer (GC) and 90 healthy age/sex matched controls using ELISA methods.

RESULTS

In only 5 (8.8%) of the patients' sera was IL-17A detectable. No IL-17A was apparent in the sera of healthy controls. The maximum concentration of IL-17A in patients was 7.004 pg/ml. Vascular and lymphatic invasions were only seen in one of the 5 positive cases. Although all of them were in the age group >60 years, no correlation was seen between age and IL-17A level. These results are somewhat different from our findings for colorectal cancer (CRC) in the same population.

CONCLUSIONS

It is possible that the inflammopathology of CRC and GC are rather different, at least in Fars, a southern province of Iran.

Functional dyspepsia and dyspepsia associated with Helicobacter pylori infection: Do they have different clinical characteristics?

BACKGROUND

Helicobacter pylori causes motor, secretory, and inflammatory gastrointestinal disorders and therefore the term "functional" has been questioned when referring to dyspepsia associated with this bacterium. Patients with dyspepsia and Helicobacter pylori infection could have clinical characteristics that differentiate them a priori from those with true functional dyspepsia.

AIMS

To determine whether there are clinical differences between patients with functional dyspepsia and Helicobacter pylori-associated dyspepsia that enable their a priori identification and to know the prevalence of Helicobacter pylori infection in patients with functional dyspepsia.

PATIENTS AND METHODS

A total of 578 patients with dyspepsia with no significant lesions detectable through endoscopy were divided into 2 groups according to the presence of Helicobacter pylori. The clinical characteristics, medical history, comorbidities, and use of health resources were compared between the two groups. A sub-analysis pairing the groups by age and sex in a 1:1 ratio was carried out to reduce bias.

RESULTS

A total of 336 patients infected with Helicobacter pylori were compared with 242 non-infected patients. The prevalence of infection in the patients with dyspeptic symptoms and no endoscopically detectable lesions was 58%. The initial analysis showed that the cases with dyspepsia and Helicobacter pylori infection were more frequently associated with overweight, obesity, high blood pressure, diabetes mellitus, and metabolic syndrome, but the paired analysis nullified all these differences.

CONCLUSIONS

The patients with dyspepsia infected with Helicobacter pylori had similar clinical characteristics to the non-infected patients and could not be differentiated a priori. The prevalence of Helicobacter pylori infection in patients with functional dyspepsia was 58% and increased with age.

UreA and cagA genes of Helicobacter pylori in Egyptian patients with laryngeal squamous cell carcinoma and benign laryngeal polyps: a cohort study

This work aims to estimate the prevalence of Helicobacter pylori ureA gene and evaluate cagA gene-positive strains in both patients of laryngeal squamous cell carcinoma (LSCC) and those with benign laryngeal polyps. This study included 49 patients confirmed pathologically to have LSCC and 15 patients with benign laryngeal polyps over a period from June 2013 to March 2015. Samples of laryngeal tissue were collected during direct laryngoscope under general anesthesia to be pathologically evaluated followed by analysis for H. pylori detection. Each laryngeal tissue sample was divided into three parts; one for bacteriological examination, the second for pathological examination and the third for PCR to detect both ureA and cagA genes. Out of 49 LSCC samples, 31 (64.6 %) was positive for ureA by PCR. Out of them, 29 samples (93.5 %) were cagA positive. Only three cases (20 %) of the benign laryngeal polyp were ureA positive by PCR and one of them was cagA positive by PCR. By the bacteriological culture, only eight samples (25.8 %) gave growth. All of them were ureA positive and only seven of them were cagA positive. There was a significant association between presence of H. pylori and LSCC as compared to benign laryngeal polyp which may contribute in the pathogenesis of laryngeal carcinoma. These results should be confirmed by further studies over larger number of cases.

Helicobacter pylori isolated from Iranian drinking water: vacA, cagA, iceA, oipA and babA2 genotype status and antimicrobial resistance properties

Despite the clinical importance of Helicobacter pylori in human gastric disorders, its exact route of transmission is still uncertain. Based on the contentious hypothesis and findings of previous investigations, water may play an important role in the transmission of H. pylori to humans. This study was carried out to investigate the vacA, cagA, oipA, iceA and babA2 genotype status and antimicrobial resistance properties of H. pylori strains isolated from the drinking water samples of four major provinces in Iran. A total of 400 drinking water samples were cultured and tested. H. pylori-positive strains were analyzed for the presence of various genotypes and antimicrobial resistance. Twelve of 400 (3%) water samples were positive for H. pylori. Samples from Isfahan province had the highest, while those from Shiraz had the lowest prevalence of H. pylori. The seasonal distribution was also determined, with the highest prevalence of bacteria in the summer season (7.36%). H. pylori strains harbored the highest levels of resistance against ampicillin (100%), erythromycin (75%), clarithromycin (75%), and trimethoprim (58.3%). The most commonly detected genotypes were vacAs1a (83.3%), vacAm1a (66.6%), vacAs2 (50%) and cagA (50%). The presence of similar genotypes in the H. pylori strains of drinking water and those of human clinical samples suggest that contaminated water maybe the sources of bacteria. Spiramycin and furazolidone are suggested for the treatment of cases of H. pylori infection.

Meta-analysis of the Prevalence of Helicobacter Pylori Infection among Children and Adults of Iran

Helicobacter pylori infection is a common health problem related to many gastrointestinal disorders. This study aims to estimate the total and age specific prevalence of Helicobacter Pylori infection in Iran. We systematically reviewed all national and international databases and finally identified 21 studies were eligible for meta-analysis. Each of them were assigned a quality score using STROBE checklist. Due to significant heterogeneity of the results, random effects model was used to estimate the pooled prevalence and 95% confidence interval of Helicobacter Pylori infection. All statistical analyses were performed using STATA. V11 software. The pooled prevalence (95% confidence interval) of Helicobacter Pylori infection among all population, children and adults were estimated as 54% (53%- 55%), 42% (41%- 44%) and 62% (61%- 64%) respectively. Helicobacter Pylori, has infected more than half of Iranian people during the last decade. Preventive strategies as well as taking into account this infection during clinical visits should be emphasized to reduce its transmission and prevalence within the community.

Helicobacter pylori ATCC 43629/NCTC 11639 Outer Membrane Vesicles (OMVs) from Biofilm and Planktonic Phase Associated with Extracellular DNA (eDNA)

Helicobacter pylori persistence is associated with its capacity to develop biofilms as a response to changing environmental conditions and stress. Extracellular DNA (eDNA) is a component of H. pylori biofilm matrix but the lack of DNase I activity supports the hypothesis that eDNA might be protected by other extracellular polymeric substances (EPS) and/or Outer Membrane Vesicles (OMVs), which bleb from the bacteria surface during growth. The aim of the present study was to both identify the eDNA presence on OMVs segregated from H. pylori ATCC 43629/NCTC 11639 biofilm (bOMVs) and its planktonic phase (pOMVs) and to characterize the physical-chemical properties of the OMVs. The presence of eDNA in bOMVs and pOMVs was initially carried out using DNase I-gold complex labeling and Transmission Electron Microscope analysis (TEM). bOMVs and pOMVs were further isolated and physical-chemical characterization carried out using dynamic light scattering (DLS) analysis. eDNA associated with OMVs was detected and quantified using a PicoGreen spectrophotometer assay, while its extraction was performed with a DNA Kit. TEM images showed that eDNA was mainly associated with the OMV membrane surfaces; while PicoGreen staining showed a four-fold increase of dsDNA in bOMVs compared with pOMVs. The eDNA extracted from OMVs was visualized using gel electrophoresis. DLS analysis indicated that both planktonic and biofilm H. pylori phenotypes generated vesicles, with a broad distribution of sizes on the nanometer scale. The DLS aggregation assay suggested that eDNA may play a role in the aggregation of OMVs, in the biofilm phenotype. Moreover, the eDNA associated with vesicle membrane may impede DNase I activity on H. pylori biofilms. These results suggest that OMVs derived from the H. pylori biofilm phenotype may play a structural role by preventing eDNA degradation by nucleases, providing a bridging function between eDNA strands on OMV surfaces and promoting aggregation.

Evaluation of Clinicopathological and Risk Factors for Nonmalignant H. Pylori Associated Gastroduodenal Disorders in Iraqi Patients

AIM:

To determine the risk factors associated with H. pylori infection and possible correlation with clinicopathological parameters.

MATERIAL AND METHODS:

Gastroduodenal biopsies were examined by rapid urease test and Gram staining. Cag A cytotoxin was detected by in situ hybridization.

RESULTS:

Risk of H. pylori acquisition reported as following: Males have 1.38 fold, rural residents have 0.63 fold, Nonsmokers have 0.39 fold, mild smokers have 18 fold, and moderate smokers have 1.4 fold while heavy smokers have 1 fold. A person who’s in contact with animals has 1.52 fold risks. Illiterates and patients with primary education have 5.36 & 3 fold risk respectively. Patients under proton pump inhibitor (PPI) therapy have 1.02 fold. Patients under NSAID therapy have 3.48 fold while nonalcoholic Patients have 0.75 fold. Patients using tap water have 0.45 fold risk. H. pylori infection positively correlated with age, weight loss, and heartburn. H. pylori inversely correlated with endoscopic diagnosis, Cag A positivity, and education level. Cag A positivity correlated with animal contact and NSAID usage.

CONCLUSIONS:

Several life style factors, education, animal contact, using of PPI, and NSAIDs increase the risk of H. pylori infection. Weight loss and heartburn cardinal signs for H. pylori infection. Endoscopic diagnosis and clinicopathological parameters not strictly associated with Cag A positivity.

Epidemiology and Diagnosis of Helicobacter pylori infection

During the period reviewed, prevalence studies were essentially performed in less economically advanced countries and a high prevalence was found. The traditional risk factors for Helicobacter pylori positivity were mostly found. Transmission studied by molecular typing showed a familial transmission. The eventual role of water transmission was explored in several studies with controversial results. Concerning diagnosis, most of the invasive and noninvasive methods used for the diagnosis of H. pylori infection are long standing with efficient performance. The most interesting recent improvements in H. pylori diagnosis include advances in endoscopy, developments in molecular methods, and the introduction of omics-based techniques. Interpretation of old or newer method should take into account the pretest probability and the prevalence of H. pylori in the population under investigation.

Helicobacter pylori Infection Is Associated with an Increased Risk of Hyperemesis Gravidarum: A Meta-Analysis

Background. Several studies have shown a possible involvement of Helicobacter pylori (H. pylori) infection in individuals with hyperemesis gravidarum (HG), but the relationship remains controversial. This meta-analysis was performed to validate and strengthen the association between HG and H. pylori infection. Methods. PubMed, Embase, and Web of Science databases up to March 20, 2014, were searched to select studies on the prevalence of H. pylori infection between pregnant women with HG and the normal pregnant control subjects. Results. Of the HG cases, 1289 (69.6%) were H. pylori-positive; however, 1045 (46.2%) were H. pylori-positive in control group. Compared to the non-HG normal pregnant controls, infection rate of H. pylori was significantly higher in pregnant women with HG (OR = 3.34, 95% CI: 2.32–4.81, P < 0.001). Subgroup analysis indicated that H. pylori infection was a risk factor of HG in Asia, Africa, and Oceania, especially in Africa (OR = 12.38, 95% CI: 7.12–21.54, P < 0.001). Conclusions. H. pylori should be considered one of the risk factors of HG, especially in the developing countries. H. pylori eradication could be considered to relieve the symptoms of HG in some intractable cases.