vacA Genotypes Research Articles

Effect of treatment failure on the CagA EPIYA motif inHelicobacter pyloristrains from Colombian subjects

AIMTo evaluate effect of treatment failure on cagA and vacA genotypes in Helicobacter pylori (H. pylori) isolates from Colombia.METHODSOne hundred and seventy-six participants infected with H. pylori from Colombia were treated during 14 d with the triple-standard therapy. Six weeks later, eradication was evaluated by 13C-Urea breath test. Patients with treatment failure were subjected to endoscopy control; biopsies obtained were used for histopathology and culture. DNA from H. pylori isolates was amplified using primers specific for cagA and vacA genes. The phylogenetic relationships among isolates obtained before and after treatment were established by conglomerate analysis based on random amplified polymorphic DNA (RAPD) fingerprinting.RESULTSTreatment effectiveness was at 74.6%. Of the participants with treatment failure, 25 accepted subjected to a second endoscopy. Prevalence of post-treatment infection was 64% (16/25) and 40% (10/25) by histology and culture, respectively. Upon comparing the cagA and vacA genotypes found before and after therapy, multiple cagA genotypes (cagA-positive and cagA-negative) were found before treatment; in contrast, cagA-negative genotypes decreased after treatment. vacA s1m1 genotype was highly prevalent in patients before and after therapy. The 3’cagA region was successfully amplified in 95.5% (21/22) of the isolates obtained before and in 81.8% (18/22) of the isolates obtained after treatment. In the isolates obtained from patients with treatment failure, it was found that 72.7% (16/22) presented alterations in the number of EPIYA motifs, compared to isolates found before treatment.CONCLUSIONUnsuccessful treatment limits colonization by low-virulence strains resulting in partial and selective eradication in mixed infections, and acts on the cagA-positive strains inducing genetic rearrangements in cagA variable region that produces a loss or gain of EPIYA repetitions.

Helicobacter pylorivacA genotype is a predominant determinant of immune response toHelicobacter pyloriCagA

AIMTo evaluate the frequency of Helicobacter pylori (H. pylori) CagA antibodies in H. pylori infected subjects and to identify potential histopathological and bacterial factors related to H. pylori CagA-immune response.METHODSSystematic data to H. pylori isolates, blood samples, gastric biopsies for histological and molecular analyses were available from 99 prospectively recruited subjects. Serological profile (anti-H. pylori, anti-CagA) was correlated with H. pylori isolates (cagA, EPIYA, vacA s/m genotype), histology (Sydney classification) and mucosal interleukin-8 (IL-8) mRNA and protein expression. Selected H. pylori strains were assessed for H. pylori CagA protein expression and IL-8 induction in co-cultivation model with AGS cells.RESULTSThirty point three percent of microbiologically confirmed H. pylori infected patients were seropositive for CagA. Majority of H. pylori isolates were cagA gene positive (93.9%) with following vacA polymorphisms: 42.4% vacA s1m1, 23.2% s1m2 and 34.3% s2m2. Anti-CagA-IgG seropositivity was strongly associated with atrophic gastritis, increased mucosal inflammation according to the Sydney score, IL-8 and cagA mRNA expression. VacA s and m polymorphisms were the major determinants for positive (vacA s1m1) or negative (vacA s2m2) anti-CagA serological immune response, which also correlated with the in vitro inflammatory potential in AGS cells. In vitro co-cultivation of representative H. pylori strains with AGS cells confirmed functional CagA translocation, which showed only partial correlation with CagA seropositivity in patients, supporting vacA as major co-determinant of the immune response.CONCLUSIONSerological immune response to H. pylori cagA+ strain in H. pylori infected patients is strongly associated with vacA polymorphism, suggesting the crucial role of bacterial factors in immune and clinical phenotype of the infection.

Prevalence of Specific Helicobacter PyloricagA, vacA, iceA, ureC Genotypes and its Clinical Relevance in the Patients with Acid-Peptic Diseases.

Virulent markers of H. pylori, the vacuolating cytotoxin (vacA), cytotoxin-associated gene A (cagA), induced by contact with epithelium factor antigen (iceA gene) and the urease C gene (ureC) may plays a major role in determining the clinical outcome of Helicobacter infections. To detect the prevalence of the cagA, vacA, ureC and iceA genotypes of H. pylori from antral biopsy specimens of patients and to associate its role in specific disease. The study was conducted at Department of Microbiology of Shree P.M. Patel College of Paramedical Sciences, Anand, Gujarat, India. Seventy one antral biopsies of symptomatic patients referred for endoscopy from October 2012 to September 2013 were subjected to Multiplex PCR. DNA isolation from 71 biopsy samples was done by using "QIAamp DNA mini kit" from QIAGEN (GmbH, Hilden, Germany). Data was analysed using Chi square (χ2) test and p-value<0.05 was considered significant. Out of the 71 biopsies screened, 22(31%) samples were positive for H. pylori by PCR, with high proportion of cagA positive (17/22 specimen; 77.27%), followed by ureC positive (4/22 specimen; 18.18%) and vacA positive (1/22 specimen; 4.54%) strains. Significant association was found between cagA and female gender (p-value=0.042). Out of 17 cagA positive strains, 9(52.94%) were found in patients with gastritis, 5(29.41%) in reflux oesophagitis and 3(17.64%) in patients with diodenal ulcer. We found 0% prevalence of iceA gene; conversely we had three peptic ulcer patients with only cagA positivity. The cagA positive strain mainly affects the patients with gastritis specifically of female gender and iceA genotype is not a useful marker associated with peptic ulcer disease. Patients should be screened for cagA genotype when reported to be a case of gastritis for early treatment to prevent further complications such as cancer.

Differences in amino acid frequency in CagA and VacA sequences of Helicobacter pylori distinguish gastric cancer from gastric MALT lymphoma.

Background Helicobacter pylori is a pathogenic bacterium that causes various gastrointestinal diseases. The most common gastric malignancies associated with H. pylori are gastric cancer and lymphoma of mucosa associated lymphoid tissue (MALT). Helicobacter pylori virulence genes, namely cagA and vacA, are known to be associated with malignancy development. Conventionally, cagA and vacA were classified by looking at partial sequences of the genes. However, such genotyping has hardly proven useful predicting different risks for gastric cancer or MALT lymphoma. In search of new loci that distinguish these diseases, we investigated the full sequences of cagA and vacA.ResultsWe compared cagA and vacA sequences of 18 and 12 H. pylori strains obtained, respectively, from patients with gastric cancer and MALT lymphoma in Oita, Japan. Conventional genotyping of cagA and vacA showed no significant difference between the two diseases. We further investigated the full protein sequences of CagA and VacA to identify loci where allele frequency was significantly different between the diseases. We found four such loci on CagA, and three such loci on VacA. We also inspected the corresponding loci on the genes of 22 gastritis strains that potentially lead to gastric cancer or MALT lymphoma in the long run. Significant differences were observed at one CagA locus between gastritis and MALT lymphoma strains, and at one VacA locus between gastritis and gastric cancer strains.ConclusionsWe found novel candidate loci in H. pylori virulence genes in association with two different types of gastric malignancies that could not be differentiated by conventional genotyping. Biological connotations of the amino acid polymorphisms merit further study.Electronic supplementary materialThe online version of this article (doi:10.1186/s13099-016-0137-x) contains supplementary material, which is available to authorized users.

INVESTIGATION OF Helicobacter pylori VIRULENCE GENOTYPE IN GASTRIC BIOPSIES BY PCR

Background: Helicobacter pylori infections has been associated with the genetic diversity of their virulence factors, the virulence genotypes are valuable as molecular marker in the diagnosis of patients with bacterial infections . Our main objective was to analyze the frequency and allelic genotype of vacA , cagA also investigate another virulence genes of H. pylori. Methods: 75 biopsies of patients with gastritis and peptic ulcer diseases were selected to investigate the presences of H. pylori and collected from them antrum biopsies, then genomic DNA was extracted from antrum biopsies using genomic DNA kit .Subsequently, the virulence genes of H. pylori were amplified using specific primers including vacA , cagA, cagE and oipA and iceA by PCR in 49 cases that positive to 16SrRNA which previously investigated. Results: A high prevalence of genes cagA (28.6%), vacAs1bm2 (56.8%), iceA2 (30.6%) and oipA (42.9%) was found, while vacA s2m1 and iceA1 genotypes was not found in our study. There was significant correlation between the presence of cagA and cagE genotypes (p = 0.02), suggesting that these two genes almost used together as cag PAI integrity marker. The presence of cagA gene was significantly associated with peptic ulceration (p ≤ 0.001), whereas different vacA genotypes or iceA2 genotype were no statistically significant with clinical outcome. Patients with peptic ulcer disease more likely to have oipA gene (61.9% ) than those with gastritis (38.1%), P = 0.037, also the presence oipA gene was statistically significant with presence iceA2. Conclusion : Most H. pylori genotypes which associated with peptic ulcer and gastritis were moderate virulent strains.

Genotyping of vacA alleles of &lt;i&gt;Helicobacter pylori&lt;/i&gt; strains recovered from some Iranian food items

Purpose: To study the vacA genotype status of H. pylori isolated from some Iranian food items.Methods: Three hundred assorted samples of fish, ham, chicken, vegetable and meat sandwiches, and minced meat were purchased and tested using culture method. Those that were H. pylori-positive were analyzed for presence of vacA genotypes using polymerase chain reaction (PCR).Results: Sixty out of 300 (20 %) food samples were positive for H. pylori. Vegetable sandwich (45 %), minced meat (32 %) and meat sandwich (20 %) were the most commonly contaminated. The most commonly detected genotypes in the meat-based foods, viz, vegetable sandwich and ready to eat fish, were vacA s1a, vacA m1a and vacA m2, respectively. The most commonly detected combined genotypes were s1am2 (45 %), s1am1a (40 %) and m1am2 (35 %).Conclusion: The presence of similar genotypes in H. pylori strains of foods and those of human clinical samples suggest that contaminated foods may be the source of bacteria for humans.Keywords: Helicobacter pylori, VacA genotypes, Genotyping, Food items

Prevalence of Helicobacter pylori cagA, vacA, and iceA genotypes in children with gastroduodenal diseases

To investigate the prevalence of cagA, vacA, and iceA genotypes in the isolated strains of Helicobacter pylori (H.pylori) from children with gastroduodenal diseases in Jiangxi, China, as well as the association between cagA, vacA, and iceA genotypes and the type of gastroduodenal diseases. The samples of gastric antral mucosa were collected from 316 children with gastroduodenal diseases in Jiangxi, and a total of 107 strains of H.pylori were isolated. The genomic DNA of these strains was extracted, and PCR was used to determine the ureA, cagA, vacA, and iceA genotypes. Of all the 107 isolated strains of H.pylori, the detection rates of ureA and cagA genes were 100% (107/107) and 94.4% (101/107) respectively. The overall detection rate of vacA gene was 100% (107/107), and the detection rates of vacAs1a, vacAs1c, vacAm1, and vacAm2 genes were 74.8% (80/107), 25.2% (27/107), 29.9% (32/107), and 69.2% (74/107) respectively, with both vacAm1 and vacAm2 genes detected in 0.9% (1/107) of all H.pylori strains. In the chimera of vacA gene, the detection rates of vacAs1a/m1, vacAs1a/m2, vacAs1c/m1, and vacAs1c/m2 genes were 26.2% (28/107), 51.4% (55/107), 3.7% (4/107), and 17.8% (19/107) respectively (P<0.001). The detection rates of iceA1 and iceA2 genes were 79.4% (85/107) and 9.3% (10/107), respectively (P<0.001), and both iceA1 and iceA2 genes were detected in 7.5% (8/107) of all strains. The detection rates of the genotypes of H.pylori showed no significant differences between the peptic ulcer, chronic gastritis, and duodenal bulbar inflammation groups (P>0.05). The dominant genotypes of H.pylori are cagA, vacAs1a/m2, and iceA1, and there are mixed infections with H.pylori strains of different genotypes in children with gastroduodenal disease from Jiangxi, China. The genotypes of H.pylori are not associated with the type of gastroduodenal disease.

English

Water availability is a major limiting factor for cowpea bean crops, especially in semiarid regions, where it is necessary to adopt more productive and tolerant genotypes and efficient strategies for water use. Thus, an experiment was carried under field conditions in the semiarid region of Pombal city, PB, Brazil. Using a completely randomised blocks design experiment and four replications, in a factorial scheme. The first factor was formed by four cowpea beans genotypes (Costela de Vaca, Pingo-de-Ouro, Paulistinha and BRS Marataoa), and the second factor consisted of five different irrigation strategies (40, 60, 80, 100 and 120% of actual evapotranspiration (ETr)). Gas exchange was evaluated at the V4 stage, dry biomatter formation at the R2 stage and crop yield until 90 days after sowing. The gas exchange from cowpea genotypes was reduced by lower irrigation amounts. For dry biomass formation, greater values in the Pingo-de-Ouro genotype were observed when irrigated with 120% of ETr. Thus, the treatment of 120% ETr improved the growth in dry matter independently of the genotype. The Costela de Vaca genotype had better CO2 assimilation rates. Paulistinha had the highest productivity among genotypes, and Costela de Vaca had the greatest water use efficiency. Key words: Assimilation rate, Vigna unguiculata, water productivity.

Relationship between vacA Types and Development of Gastroduodenal Diseases.

The Helicobacter pylori vacuolating cytotoxin (VacA) is a secreted pore-forming toxin and a major virulence factor in the pathogenesis of H. pylori infection. While VacA is present in almost all strains, only some forms are toxigenic and pathogenic. While vacA and its genotypes are considered as markers of H. pylori-related diseases or disorders, the pathophysiological mechanisms of VacA and its genotypes remain controversial. This review outlines key findings of publications regarding vacA with emphasis on the relationship between vacA genotypes and the development of human disease.

Study of the clinical relevance of Helicobacter pylori virulence genes to gastric diseases among Egyptian patients

Background and study aimsHelicobacter pylori infection is common in Egypt. It has been associated with gastritis, ulcers and it is a risk factor for gastric cancer. We aimed to study the correlation between the presence of H. pylori virulence factors and the histopathological and endoscopic findings in gastric biopsies. Patients and methodsGastric biopsies from thirty seven patients scheduled for diagnostic endoscopy in Cairo University hospital were included in the study. All gastric biopsies were subjected to histopathological examination and PCR assay for detection of 16S rRNA gene to diagnose H. pylori infection, detection of H. pylori virulence factors by PCR for cagA and vacA genotypes and serological analysis of H. pylori (cagA, vacA, P25, and P19) IgG antibodies by immunoblot assay were done. ResultsH. pylori infection was detected in 23 (62.2%) cases by histopathology while 28/37 (75.7%) were positive for H. pylori 16S rRNA gene by PCR. By PCR seventeen samples out of 37 (45.9%) were positive for cagA gene and five (13.5%) for cag empty site gene. ConclusionThe most common vacA genotype identified was vacA s2m2 genotype in 10 (27.02%). No statistical correlation was found between IgG antibodies against different antigens of H. pylori virulence factors (cagA, vacA, p25, and p19) and the degree of gastritis except for IgG antibodies against the UreA antigen.

Helicobacter pylori vacA Genotypes in Chronic Gastritis and Gastric Carcinoma Patients from Macau, China.

Helicobacter pylori is the major triggering factor for gastric carcinoma, but only a small proportion of infected patients develop this disease. Differences in virulence observed among H. pylori strains, namely in the vacuolating cytotoxin vacA gene, may contribute to this discrepancy. Infection with vacA s1, i1 and m1 strains increases the risk for progression of gastric premalignant lesions and for gastric carcinoma. However, in East Asian countries most of the H. pylori strains are vacA s1, regardless of the patients’ clinical status, and the significance of the vacA i1 and m1 genotypes for gastric carcinoma in this geographic area remains to be fully elucidated. The aim of the present study was to investigate this relationship in 290 patients from Macau, China. Using very sensitive and accurate genotyping methods, we detected infection with vacA i1 and with vacA m1 strains in, respectively, 85.2% and 52.6% of the patients that were infected with single genotypes. The prevalence of cagA-positive strains was 87.5%. No significant associations were observed between vacA genotypes or cagA and gastric carcinoma. It is worth noting that 37.5% of the infected patients had coexistence of H. pylori strains with different vacA genotypes. Additional studies directed to other H. pylori virulence factors should be performed to identify high risk patients in East Asia.

Primary resistance of Helicobacter pylori is still low in Southern Austria

ObjectivesWe determined primary and secondary resistance rates of H. pylori in different regions of Austria and potential bacterial and host factors associated with resistance. MethodsIn a prospective multicentre study H. pylori was cultivated from biopsies and susceptibility testing was performed according to EUCAST. Resistance to clarithromycin and levofloxacin was determined by sequencing of the resistance-determining regions of 23S rRNA and gyrA genes. cagA, vacA and babA2 genotypes were determined. ResultsA total of 1266 patients were included. 178 isolates were cultured: 128 from patients without prior eradication therapy, 50 from patients after failed eradication. Primary resistance to clarithromycin, levofloxacin and metronidazole were 17.2%, 9.4% and 10.2%, respectively. Secondary resistance to clarithromycin, levofloxacin and metronidazole were 64%, 18% and 44%, respectively. Prior eradication was associated with a higher risk of clarithromycin as well as metronidazole resistance (OR=8.1; 95% CI 3.8–17.1 and OR 5.7; 95% CI 2.5–13, respectively). ConclusionPrimary resistance to both clarithromycin and levofloxacin was markedly lower in Southern Austria than recently reported.

English

Helicobactor pylori (H. pylori) has been strongly associated with gastritis, peptic ulcer and is linked to an increased risk of gastric cancer. The cytotoxin-associated gene product (cagA) and the vacuolating cytotoxin (vacA) have been implicated as two major virulence factors of H. pylori. Since there is an increasing evidence that genetic variability of H. pylori may have clinical importance, we aimed to evaluate different vacA genotypes and reveal its relationship with endoscopic and transmission electron microscopy (TEM) findings among H. pylori infected Egyptian patients. Forty H. pylori infected patients possessing vacA gene who underwent upper endoscopic examination were considered to be infected with H. pylori when rapid urease test and detection of 16S rRNA in gastric biopsy recorded positive. Both vacA and cagA genotypes were detected by polymerase chain reaction (PCR). The TEM was performed to assess the ultra-structure of the gastric mucosa. Four vacA genotypes were identified, the most prominent was the s2/m2 allele combination (52.5%) followed by s1/m1 (27.5%), s1/m2 (17.5%) and s2/m1 genotype was found just in one H. pylori strain (2.5%). There were significant correlations between vacA s2/m2 and gastritis (65.2%), and vacA s1/m1 and peptic ulceration (57%). The cagA gene was associated with 38% of vacA genotypes and 60% of which were significantly associated with vacA s1/m1 genotype with the development of severe gastritis reaching up to gastric ulcer. The TEM revealed H. pylori spiral and coccoid forms, cytoplasmic vacuolar degeneration caused by vacA, swollen mitochondria and dilated rough endoplasmic reticulum. In Egypt where prevalence of H. pylori infection is high, genotyping of H. pylori virulence factors can help to predict patients who are at a high risk of related gastroduodenal diseases. Although H. pylori with vacA s2/m2 genotype is mostly related to low level of virulent strains yet, significant crosstalk between H. pylori strains harboring both vacA s1/m1 and cagA gene provides crucial insights into virulence of high level. Key words: Helicobactor pylori, vacA genotyping, cagA, gastritis, peptic ulcer.

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.

Mo1246 Virulence Factors of Helicobactor pylori Among Patients With Functional Dyspepsia and Peptic Ulcer in the Community: A Study by CagA and vacA Genotyping

Mo1246 Virulence Factors of Helicobactor pylori Among Patients With Functional Dyspepsia and Peptic Ulcer in the Community: A Study by CagA and vacA Genotyping

Sa1376 Systemic Immunologic Response to H. pylori CagA Is Modulated by Bacterial vacA Genotypes

Sa1376 Systemic Immunologic Response to H. pylori CagA Is Modulated by Bacterial vacA Genotypes

Helicobacter pylori in bottled mineral water: genotyping and antimicrobial resistance properties.

BackgroundUp to now, fecal–oral and oral–oral are the most commonly known routes for transmission of H. pylori, therefore, contaminated water can play an important role in transmission of H. pylori to humans. Genotyping using virulence markers of H. pylori is one of the best approaches to study the correlations between H. pylori isolates from different samples. The present research was carried out to study the vacA, cagA, cagE, oipA, iceA and babA2 genotyping and antimicrobial resistance properties of H. pylori isolated from the bottled mineral water samples of Iran.ResultsOf 450 samples studied, 8 samples (1.77 %) were contaminated with H. pylori. Brand C of bottled mineral water had the highest prevalence of H. pylori (3.63 %). The bottled mineral water samples of July month had the highest levels of H. pylori-contamination (50 %). H. pylori strains had the highest levels of resistance against metronidazole (62.5 %), erythromycin (62.5 %), clarithromycin (62.5 %), amoxicillin (62.5 %) and trimethoprim (62.5 %). Totally, 12.5 % of strains were resistant to more than 6 antibiotics. VvacAs1a (100 %), vacAm1a (87.5 %), cagA (62.5 %), iceA1 (62.5 %), oipA (25 %), babA2 (25 %) and cagE (37.5 %) were the most commonly detected genotypes. M1as1a (62.5 %), m1as2 (37.5 %), m2s2 (37.5 %) and S1a/cagA+/IceA2/oipA-/babA2-/cagE- (50 %) were the most commonly detected combined genotypes.ConclusionsContaminated bottled mineral water maybe the sources of virulent and resistant strains H. pylori. Careful monitoring of bottled mineral water production may reduce the risk of H. pylori transmission into the human population.

&lt;i&gt;VacA, CagA, IceA&lt;/i&gt; and &lt;i&gt;OipA&lt;/i&gt; Genotype Status of &lt;i&gt;Helicobacter pylori&lt;/i&gt; Isolated from Biopsy Samples from Iranian Dogs

Purpose: To investigate the state of vacA, cagA, oipA and iceA genotypes of H. pylori isolated from gastric biopsy samples of dogs.Methods: A total of 240 gastric biopsy samples were taken from 240 dogs using gastric endoscope. All the samples were cultured and H. pylori-positive samples were analyzed for the presence of various genotypes using polymerase chain reaction (PCR).Results: Thirteen out of 240 (5.41 %) samples were positive for H. pylori with a higher prevalence of the bacterium in dogs with gastric ulcer (6.36 %). The most commonly detected genotypes were vacA s1a (53.84 %), cagA (46.15 %) and vacA m2 (38.46 %). Total prevalence of iceA1, iceA2 and oipA genotypes were 23.07, 10.8 and 10.81 %, respectively. M2s1a (30.76 %), m1am2 (30.76 %) and m1as1a (23.07 %) had the highest prevalence among other detected combined genotypes. Twenty-two different genotypic combinations were detected with higher prevalence of s1a/cagA+/iceA1/oipA- (23.07 %), m2/cagA+/iceA1/oipA- (23.07 %), and s1b/cagA+/iceA1/oipA- (15.38 %) genotypes.Conclusion: The presence of similar genotypes in H. pylori strains of gastric biopsy samples of dogs and those of human clinical specimens suggest that dogs may be the source of the bacterium. Proper handwashing and avoidance contact with feces and saliva of dogs are recommended to prevent transmission of H. pylori.Keywords: Helicobacter pylori, Genotype, Genotyping, Gastric biopsy, Iranian dogs

VacA, cagA, iceA and oipA genotypes status and antimicrobial resistance properties of Helicobacter pylori isolated from various types of ready to eat foods.

BackgroundDespite the high clinical standing of Helicobacter pylori, its exact routes of transmission and origin have not been determined. Based on the contentious hypothesis, foods play an important roles in the transmission of H. pylori to humans. The present study was carried out to investigate the vacA, cagA, oipA and iceA genotypes status of H. pylori isolated from the various types of ready to eat foods.MethodsA total of 550 ready to eat food samples were cultured and tested. H. pylori-positive strains were analyzed for the presence of various genotypes and antimicrobial resistance pattern.ResultsSeventy four out of 550 (13.45 %) samples were positive for H. pylori. Olvie salad (36 %), restaurant salad (30 %), fruit salad (28 %) and soup (22 %) were the most commonly contaminated. H. pylori strains harbored the highest levels of resistance against amoxicillin (94.59 %), ampicillin (93.24 %), metronidazole (89.18 %) and tetracycline (72.97 %). The most commonly detected genotypes were vacA s1a (78.37 %), vacA m2 (75.67 %), vacA m1a (51.35 %) and cagA (41.89 %). The prevalence of iceA1, iceA2 and oipA genotypes were 13.51, 4.05 and 18.91 %, respectively. S1am2 (70.27 %), s1am1a (39.18 %) and m1am2 (31.08 %) were the most commonly detected combined genotypes. Of 40 different genotypic combinations, s1a/cagA+/iceA1/oipA− (12.16 %), s1a/cagA+/iceA1/oipA+ (10.81 %) and s1a/cagA−/iceA1/oipA+ (10.81 %) were the most prevalent.ConclusionsThe present investigation showed that some types of ready to eat food samples maybe the sources of resistant and virulent strains of H. pylori. Warily use of antibiotics with respect to the results of disk diffusion method and careful health monitoring on food and staffs of food producing companies maybe reduce the risk of H. pylori in foods.

VacA Genotype Status of Helicobacter pylori Isolated from Foods with Animal Origin.

According to controversial theories and results of studies, foods with animal origins play an important role in the transmission of H. pylori to human. The aim of this study was to determine the distribution of vacA genotypes of H. pylori, isolated from milk and meat samples of cow, sheep, goat, camel, and buffalo. Eight hundred and twenty raw milk and meat samples were collected from various parts of Iran. Samples were cultured and those found positive for H. pylori were analyzed for the presence of various genotypes of vacA gene. Out of 420 milk and 400 meat samples, 92 (21.90%) and 105 (26.25%) were positive for H. pylori, respectively. The most commonly detected genotypes in the vacA gene were s1a (86.80%), m1a (79.18%), s1b (69.54%), and m1b (63.45%) and detected combined genotypes were mostly m1as1a (68.52%), m1as1b (60.40%), m1bs1b (55.83%), and m1bs1a (53.29%). High presence of bacteria in the milk and meat samples of sheep represents that sheep may be the natural host of H. pylori. High presence of H. pylori strains in milk and meat samples similar to vacA genotypes in human being suggests that milk and meat samples could be the sources of bacteria for human.