vacA genotypes of Helicobacter pylori in the oral cavity and stomach of patients with chronic gastritis and gastric ulcer

Introduction

Helicobacter pylori adheres to various components of the human saliva. Therefore, the objective of this research was to simultaneously detect H. pylori in saliva and in gastric biopsy, and to determine the agreement between the vacA genotypes in both saliva and gastric biopsy.

Materials and methods

A total of 162 patients with chronic gastritis and 34 with gastric ulcer were studied, and saliva and biopsy samples were collected from each patient. H. pylori DNA was detected by conventional PCR and nested PCR was used for vacA genotyping.

Results

In 24% of the patients (47/196) H. pylori DNA was found in saliva and in biopsy; 52.5% (103/196) were saliva^negative/biopsy^positive and 6.6% (13/196) were saliva^positive/biopsy^negative. In either or both H. pylori vacAs1m1 or s1m2 genotypes were detected in saliva in 41.5% of the patients with chronic gastritis. Forty-seven percent had >1 genotype, and the s1m1/s1m2 combination was found in 36% of them. H. pylori vacAs1m1 and s1m2 were also found in the saliva and biopsy of patients with gastric ulcer. The genotypes found in saliva and biopsy of the same patient had 51.1% agreement. In 27.6% of the 47 patients saliva^positive/biopsy^positive two genotypes were found in saliva, and one or both in the stomach.

Conclusions

The s1m1/s1m2 genotypes, alone or together, are found simultaneously in saliva and gastric biopsy of the same patient. These results suggest that H. pylori reaches the oral cavity by various ways, and that saliva can be the transmitting and re-infecting vector.     

High risk of failing eradication of Helicobacter pylori in patients with diabetes: A meta-analysis

Aims

Eradication of Helicobacter pylori (HP) is an effective approach to improve intestinal symptoms and prevent gastric cancer. However, there has been concern that the presence of diabetes reduces the effectiveness of antibiotics. We performed this meta-analysis to investigate the effect of diabetes on the risk of failing eradication in patients with diabetes.

Methods

An electronic literature search was conducted using Biosis, MEDLINE, Embase, PASCAL, and SciSearch through November 30, 2012. Selected studies had to provide data on the number of individuals who received treatment for HP infection and on the failure of HP eradication in groups with and without diabetes. Two authors independently extracted relevant data.

Results

Data were obtained from 8 eligible studies (693 total participants including 273 participants with diabetes). Overall, the pooled risk ratio (RR) of failing HP eradication for diabetic patients compared with non-diabetic participants was 2.19 [95%CI, 1.65–2.90] (P < 0.001). Excluding the 2 studies that used a non-standard protocol for HP eradication, individuals with diabetes had a higher risk of failure of eradication compared to those without diabetes (RR = 2.31 [95%CI, 1.72–3.11]).

Conclusions

Current meta-analysis confirmed the higher risk of HP eradication failure in individuals with diabetes compared with those without diabetes, suggesting the necessity of prolonging treatment or developing a new regimen for HP eradication in patients with diabetes.     

Prevalence of Helicobacter pylori cagA, iceA and babA2 alleles in Brazilian patients with upper gastrointestinal diseases

Helicobacter pylori is an important human pathogen associated with gastrointestinal diseases such as gastritis, gastric and duodenal ulcer (peptic ulcer disease, PUD), and gastric cancer. A number of pathogenic factors have been described for this bacterium, and some of them have been proposed as markers for the prediction of the clinical outcome. However, with the exception of the cag and vacA status, there is no universal consensus regarding the importance of the other virulence factors. Therefore, the aim of this study was to investigate the status of H. pylori strains regarding the babA and iceA alleles, as well as the cagA genotype, to reveal any association between these genotypes and clinical outcomes in Brazilian patients. The great majority (92.6%) of the strains were typed as iceA1, while 40.4% were found to possess the babA2 allele. The cagA gene was detected in 73.4% of the strains. The iceA2 and cagA genotypes were associated with PUD, while iceA1 was negatively correlated with PUD. However, considering the high percentage of strains typed as iceA1, these associations must be treated with caution. No clinical entity was associated with the babA2 allele. These results suggest that iceA1 is not a good marker for the diseases associated with H. pylori infection in Brazil. Further studies are needed in order to elucidate the relevance of the babA status, because other studies performed in Brazil have associated the babA2 allele with clinical outcomes. These results also indicate the existence of regional differences in the H. pylori genotypes and their association with clinical outcomes.     

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.     

Bacterial flora concurrent with Helicobacter pylori in the stomach of patients with upper gastrointestinal diseases

AIM: To investigate the non-Helicobacter pylori (H. pylori) bacterial flora concurrent with H. pylori infection.METHODS: A total of 103 gastric biopsy specimens from H. pylori positive patients were selected for bacterial culture. All the non-H. pylori bacterial isolates were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).RESULTS: A total of 201 non-H. pylori bacterial isolates were cultivated from 67 (65.0%) of the 103 gastric samples, including 153 isolates identified successfully at species level and 48 at genus level by MALDI-TOF MS. The dominant species were Streptococcus, Neisseria, Rothia and Staphylococcus, which differed from the predominantly acid resistant species reported previously in healthy volunteers. The prevalence of non-H. pylori bacteria was higher in non-ulcer dyspepsia group than in gastric ulcer group (100% vs 42.9%, P < 0.001). Six bacterial species with urease activity (Staphylococcus epidermidis, Staphylococcus warneri, Staphylococcus capitis, Staphylococcus aureus, Brevibacterium spp. and Klebsiella pneumoniae) were also isolated.CONCLUSION: There is a high prevalence of the non-H. pylori bacteria concurrent with H. pylori infection, and the non-H. pylori bacteria may also play important as-yet-undiscovered roles in the pathogenesis of stomach disorders.     

Prevalence of Helicobacter pylori virulence genotypes among children in Eastern Turkey

AIM:To identify the virulence genotypes of Helicobacter pylori(H.pylori)if present in children in Eastern Turkey and if those genotypes are mostly associated with severe clinical presentations.METHODS:A total of 49 H.pylori positive Turkish children(42 with antral nodularity and 7 with peptic ulcer)who underwent upper gastrointestinal endoscopy with abdominal symptoms during the period from March 2011 to September 2012 were enrolled in this study.Antral nodularity was diagnosed endoscopically by two of the authors.We determined for the presence of cagA,vacA,cagE,iceA and babA2 genotypes of H.pylori isolates in DNA obtained directly from frozen gastric biopsy samples by polymerase chain reaction test using specific primers.RESULTS:Of the 49 H.pylori isolates studied,61.2%,91.8%,22.4%,28.6%,57.1%and 40.8%were positive for the cagA,vacA s1,cagE,iceA1,iceA2 and babA2 genes,respectively.We showed that the most common vacA subtype was s1a(79.6%).However,the s2 gene was found less frequently with an isolation rate of 8.2%of the H.pylori isolates.The genotypes iceA2 and vacA s1m2 were the most frequently found types in children with antral nodularity.In addition,the genotypes iceA1,babA2 and vacA s1m1 were found in similar ratios in all the H.pylori isolates obtained from children with peptic ulcer.The genotypes vacA s2m1and s1c were not observed in any of isolates studied.CONCLUSION:This study showed that vacA s1m2,cagA and iceA2 were the most common genotypes,and no association between antral nodularity and genotypes was observed.     

More Favorable Outcomes with Peptic Ulcer Bleeding Due to Helicobacter Pylori

Background

Acute upper gastrointestinal bleeding is a common complication of peptic ulcer disease, often caused by Helicobacter pylori and nonsteroidal anti-inflammatory drug (NSAID) use. The purpose of this study was to determine whether the cause and biologic behavior of ulcers associated with acute upper gastrointestinal bleeding might lead to divergent patient outcomes.

Methods

In this Institutional Review Board-approved study, we compared clinical features and outcomes of patients with acute upper gastrointestinal bleeding due to ulcers categorized into 4 groups: Helicobacter pylori positive or negative combined with NSAID usage positive or negative. Likelihood chi-squared analyses were utilized for group comparisons and stepwise multiple logistic regression models were utilized to determine which factors were related to bleeding outcomes.

Results

Of 2242 patients with upper gastrointestinal bleeding, 575 (26%) had gastroduodenal ulcer disease, and of those with appropriate diagnostic testing, approximately half (228, 10% overall) had evidence of Helicobacter pylori infection and half (216, 10% overall) had no evidence of Helicobacter pylori infection. Patients without Helicobacter pylori infection had significantly more comorbid conditions than those with Helicobacter pylori and higher Charlson Index comorbidity scores (2.6 ± 2.6 [mean and SD] vs 1.9 ± 2.3, P = .003). Hospital length of stay was significantly longer for Helicobacter pylori-negative patients (mean 11.4 ± 21.7 vs 6 ± 8.5 days and median 5.5 vs 3 days, P <.001 and <.001, respectively). Rebleeding events within 30 days were more frequent in Helicobacter pylori-negative patients than Helicobacter pylori-positive patients (11% vs 5%, P = .009). Rebleeding was most frequent in patients without Helicobacter pylori and with no reported use of NSAIDS (18%, P = .01).

Conclusions

Helicobacter pylori-negative ulcers were associated with poorer outcomes regardless of use of NSAIDs. Patients with ulcers negative for Helicobacter pylori and no history of NSAID use had the worst outcomes and had more severe systemic disease.     

Prevalence of Helicobacter pylori infection and risk of upper gastrointestinal ulcer in patients with rheumatoid arthritis in Japan

We evaluated the prevalence of Helicobacter pylori infection and the association of H. pylori infection and/or nonsteroidal anti-inflammatory drug (NSAID) use with upper gastrointestinal (UGI) ulcers in a cohort of Japanese patients with rheumatoid arthritis (RA). Using the clinical database of the cohort of RA patients and the serum titers of H. pylori antibody, 1815 patients were analyzed. Clinical data were successfully collected for 1529 patients over 2 years, and the history of NSAID use and the occurrence of newly diagnosed UGI ulcer were ascertained by patient self-reports and confirmed by their medical records. A total of 871 patients (49.3%) were H. pylori antibody-positive. Rates of positivity for H. pylori in patients with and without NSAID use were 47.5% and 54.7%, respectively (odds ratio = 0.75, 95% confidence intervals [CI]: 0.58–0.96). The incidence of newly diagnosed UGI ulcer was 0% in the H. pylori−/NSAID− group, 1.24% in the H. pylori−/NSAID+ group, 1.06% in the H. pylori+/NSAID− group, and 3.46% in the H. pylori+/NSAID+ group. The odds ratios of H. pylori infection and NSAID for the occurrence of new UGI ulcers after adjusting for age and sex were 2.97 (95% CI: 1.19–7.38) and 4.31 (95% CI: 0.57–32.4), respectively. Although the prevalence of H. pylori antibody was low in patients with RA compared with that in healthy Japanese individuals, H. pylori infection was a significant risk factor for UGI ulcer in patients with RA.     

Helicobacter pylori eradication in the management of patients with idiopathic thrombocytopenic purpura

PURPOSE: To investigate the relation between Helicobacter pylori infection and the clinical features of idiopathic thrombocytopenic purpura (ITP), and to examine the effects of H. pylori eradication on platelet counts. METHODS: A(13)C urea breath test for H. pylori infection was performed in a cohort of 137 consecutive patients with ITP. Patients who tested positive received standard eradication therapy if their platelet count was <50 x 10(9)/L or if they had symptoms of dyspepsia. RESULTS: H. pylori infection was detected in 64 patients (47%), and was not associated with dyspepsia or other clinical or laboratory features. Eradication therapy was successfully administered to 52 patients. Platelet responses were observed in 17 (33%) of these patients, which lasted for more than 1 year in 11 patients. Duration of ITP was shorter among responders than nonresponders. Only one response was observed among patients with severe thrombocytopenia (platelet count <30 x 10(9)/L). CONCLUSION: The prevalence of H. pylori infection in patients with ITP is similar to that found in the general population. Infection is not associated with distinctive features of the disease. H. pylori eradication may improve the platelet counts in adults in whom the ITP is of recent onset and in those with less severe degrees of thrombocytopenia, but was not effective in patients with chronic severe ITP.     

Clinical proteomics identifies potential biomarkers in Helicobacter pylori for gastrointestinal diseases

The development of gastrointestinal diseases has been found to be associated with Helicobacter pylori(H. pylori) infection and various biochemical stresses in stomach and intestine. These stresses, such as oxidative, osmotic and acid stresses, may bring about bidirectional effects on both hosts and H. pylori, leading to changes of protein expression in their proteomes. Therefore, proteins differentially expressed in H. pylori under various stresses not only reflect gastrointestinal environment but also provide useful biomarkers for disease diagnosis and prognosis. In this regard, proteomic technology is an ideal tool to identify potential biomarkers as it can systematically monitor proteins and protein variation on a large scale of cell’s translational landscape, permitting in-depth analyses of host and pathogen interactions. By performing twodimensional polyacrylamide gel electrophoresis(2-DE) followed by liquid chromatography-nanoESI-mass spectrometry(nanoLC-MS/MS), we have successfully pinpointed alkylhydroperoxide reductase(AhpC), neutrophil-activating protein and non-heme iron-binding ferritin as three prospective biomarkers showing upregulation in H. pylori under oxidative, osmotic and acid stresses, respectively. Further biochemical characterization reveals that various environmental stresses can induce protein structure change and functional conversion in the identified biomarkers. Especially salient is the antioxidant enzyme AhpC, an abundant antioxidant protein present in H. pylori. It switches from a peroxide reductase of low-molecular-weight(LMW) oligomers to a molecular chaperone of high-molecular-weight(HMW) complexes under oxidative stress. Different seropositivy responses against LMW or HMW AhpC in H. pylori-infected patients faithfully match the disease progression from disease-free healthy persons to patients with gastric ulcer and cancer. These results has established AhpC of H. pylori as a promising diagnostic marker for gastrointestinal maladies, and highlight the utility of clinical proteomics for identifying disease biomarkers that can be uniquely applied to disease-oriented translational medicine.     

Low prevalence of H. pylori infection in patients with gastroparesis

Background

The histopathology of the gastric mucosa in patients with gastroparesis, a condition characterized by gastric retention without obstruction, has not been described.

Aim

To test the hypothesis that reactive gastropathy is more common in patients with gastroparesis than in subjects with normal gastric motility.

Methods

We compared the prevalence of reactive gastropathy, Helicobacter pylori infection, chronic gastritis, and intestinal metaplasia in patients with and without a clinical diagnosis of gastroparesis extracted from a national database of subjects with gastric biopsies (1/2008–6/2012).

Results

There were 3040 patients with gastroparesis (median age 58 years, 67.3% women) and 575,895 controls (median age 57 years, 62.0% women) with no evidence of gastroparesis. Reactive gastropathy was marginally more prevalent in patients with gastroparesis (18.9%) than in controls (17.0%). In contrast, H. pylori gastritis was present in 10.8% of controls, but only in 5.9% patients with gastroparesis (OR 0.52; 95% CI 0.45–0.61). Intestinal metaplasia was also less common in patients with gastroparesis (2.8% versus 3.9%; OR 0.82; 95% CI 0.58–0.89).

Conclusions

The low prevalence of H. pylori infection in gastroparesis could be explained by higher rates of previous eradication, conditions unfavourable to the survival of H. pylori, or a protective effect of mucosal inflammation against the development of motility disorders.     

Helicobacter pylori Seropositivity Is Associated with Gastric Cancer Regardless of Tumor Subtype in Korea

Background/Aims

To evaluate the association between Helicobacter pylori (H. pylori) infection and gastric cancer (GC) according to tumor subtype in Korea.

Methods

H. pylori status was determined serologically using the enzyme-linked immunosorbent assay. In total, 2,819 patients with GC and 562 healthy controls were studied. A logistic regression method was used after adjusting for possible confounders.

Results

The prevalence of H. pylori infection was significantly higher in the GC patients (84.7%) than in the controls (66.7%) (odds ratio [OR], 3.13; 95% confidence interval [CI], 2.46-3.97). The adjusted OR was significantly higher in H. pylori-infected patients aged <60 years (OR, 4.69; 95% CI, 3.44-6.38) than in those aged ≥60 years (OR, 1.48; 95% CI, 0.88-2.46; p<0.001). Subgroup analyses revealed no differences in seroprevalence between early gastric cancer (84.8%; OR, 3.01; 95% CI, 2.27-4.01) and advanced gastric cancer (84.6%; OR, 2.94; 95% CI, 2.24-3.85), cardia cancer (83.8%; OR, 2.98; 95% CI, 2.16-4.02) and noncardia cancer (84.8%; OR, 3.17; 95% CI, 2.48-4.04), and differentiated carcinoma (82.7%; OR, 2.99; 95% CI, 2.21-4.04) and undifferentiated carcinoma (86.8%; OR, 3.05; 95% CI, 2.32-4.00).

Conclusions

The seroprevalence of H. pylori was higher in GC patients than in healthy controls, especially in younger patients. H. pylori infection is associated with GC, regardless of the tumor location, stage, or differentiation.     

Characteristics of gastric cancer in peptic ulcer patients with Helicobacter pylori infection

AIM:To evaluate the incidence and clinical characteristics of gastric cancer(GC) in peptic ulcer patients with Helicobacter pylori(H.pylori) infection.METHODS:Between January 2003 and December 2013, the medical records of patients diagnosed with GC were retrospectively reviewed.Those with previous gastric ulcer(GU) and H.pylori infection were assigned to the Hp GU-GC group(n = 86) and those with previous duodenal ulcer(DU) disease and H.pylori infection were assigned to the Hp DUGC group(n = 35).The incidence rates of GC in the Hp GU-GC and Hp DU-GC groups were analyzed.Data on demographics(age, gender, peptic ulcer complications and cancer treatment), GC clinical characteristics [location, pathological diagnosis, differentiation, T stage, Lauren's classification, atrophy of surrounding mucosa and intestinal metaplasia(IM)], outcome of eradication therapy for H.pylori infection, esophagogastroduodenoscopy number and the duration until GC onset were reviewed.Univariate and multivariate analyses were performed to identify factors influencing GC development.The relative risk of GC was evaluated using a Cox proportional hazards model.RESULTS:The incidence rates of GC were 3.60%(86/2387) in the Hp GU-GC group and 1.66%(35/2098) in the Hp DU-GC group.The annual incidence was 0.41% in the Hp GU-GC group and 0.11% in the Hp DUGC group.The rates of moderate-to-severe atrophy of the surrounding mucosa and IM were higher in the Hp GU-GC group than in the Hp DU-GC group(86% vs 34.3%, respectively, and 61.6% vs 14.3%, respectively, P 0.05).In the univariate analysis, atrophy of surrounding mucosa, IM and eradication therapy for H.pylori infection were significantly associated with the development of GC(P 0.05).There was no significant difference in the prognosis of GC patients between the Hp GU-GC and Hp DU-GC groups(P = 0.347).The relative risk of GC development in the Hp GUGC group compared to that of the Hp DU-GC group,after correction for age and gender,was 1.71(95%CI:1.09-2.70;P=0.02).CONCLUSION:GU patients with H.pylori infection had higher GC incidence rates and relative risks.Atrophy of surrounding mucosa,IM and eradication therapy were associated with GC.     

Helicobacter pylori and skin autoimmune diseases

Autoimmune skin diseases are characterized by dysregulation of the immune system resulting in a loss of tolerance to skin self-antigen(s). The prolonged interaction between the bacterium and host immune mechanisms makes Helicobacter pylori(H. pylori) a plausible infectious agent for triggering autoimmunity. Epidemiological and experimental data now point to a strong relation of H. pylori infection on the development of many extragastric diseases, including several allergic and autoimmune diseases. H. pylori antigens activate cross-reactive T cells and induce autoantibodies production. Microbial heat shock proteins(HSP) play an important role of in the pathogenesis of autoimmune diseases because of the high level of sequence homology with human HSP. Eradication of H. pylori infection has been shown to be effective in some patients with chronic autoimmune urticaria, psoriasis, alopecia areata and Schoenlein-Henoch purpura. There is conflicting and controversial data regarding the association of H. pylori infection with Beh et’s disease, scleroderma and autoimmune bullous diseases. No data are available evaluating the association of H. pylori infection with other skin autoimmune diseases, such as vitiligo, cutaneous lupus erythematosus and dermatomyositis. The epidemiological and experimental evidence for a possible role of H. pylori infection in skin autoimmune diseases are the subject of this review.     

Distribution of vacA and cagA genotypes of Helicobacter pylori in Kuwait

There is considerable geographical variation in the distribution of allelic types of Helicobacter pylori. This first study from Kuwait determined the prevalence of cagA and vacA genotypes among 117 unselected patients attending a gastroenterology center. We found that whereas vacA s1 and s2 types were equally likely to be present in biopsies obtained from patients of Middle-Eastern origin, African Arabs were predominantly infected with s2 type and South-Asians the s1 type. South Asians most frequently carried the cagA positive genotype with Bangladeshis showing the highest prevalence rate of 87%.     

High rate of Helicobacter pylori reinfection in Lithuanian peptic ulcer patients

AIM: To evaluate the frequency of Helicobacter pylori(H. pylori) reinfection in peptic ulcer patients during 9 years after H. pylori eradication.METHODS: We invited 117 peptic ulcer patients in whom eradication of H. pylori was confirmed 1 year after eradication treatment both by histology and by rapid urease test. In total, 57 patients were available for the study procedures: 34(59.6%) male, 23(40.4%) female; mean age 52.3 ± 13.0 years. There were 45(78.9%) patients with duodenal ulcer and 12(21.1%) with gastric ulcer. H. pylori was diagnosed by a rapid urease test and histology if endoscopy was performed. If endoscopy was refused, H. pylori was diagnosed by the C14-urea breath test and serology. H. pylori was established if at least one of the tests was positive.RESULTS: The mean follow-up was 8.9 ± 1.0 years(range, 6-12). H. pylori was established in 15 patients. In 2 H. pylori-negative patients, H. pylori was established during the follow-up period and eradicated. Therefore, we consider that reinfection occurred in 17 patients. In the per protocol analysis, reinfection was established in 17 of 57(29.8%; 95%CI: 19.2-42.2) patients during the follow-up period. The annual rate of infection was 3.36%. If all non-responders were considered H. pylori-negative, reinfection would be 14.5%(17/117), the annual ratebeing 1.63%. The mean age of patients with reinfection was 51.8 ± 14.0 years, and without reinfection was 52.5 ± 13.0 years, P 0.05; the mean body mass index of patients with reinfection was 27.2 ± 4.1 kg/m2, and without reinfection was 25.7 ± 4.2 kg/m2, P 0.05. There were no differences in the reinfection rates according the location of the peptic ulcer, the eradication regimen used, and smoking status.CONCLUSION: The reinfection rate of H. pylori is relatively high in Lithuania and probably related to the high prevalence of H. pylori, what may reflect differences in the socioeconomic status between Western and Eastern European countries.     

Helicobacter pylori infection,gastrin and cyclooxygenase-2 in gastric carcinogenesis

Gastric cancer is one of the most frequent neoplasms and a main cause of death worldwide, especially in China and Japan. Numerous epidemiological, animal and experimental studies support a positive association between chronic Helicobacter pylori(H. pylori) infec-tion and the development of gastric cancer. However, the exact mechanism whereby H. pylori causes gastric carcinogenesis remains unclear. It has been demon-strated that expression of cyclooxygenase-2(COX-2) is elevated in gastric carcinomas and in their precursor le-sions. In this review, we present the latest clinical and experimental evidence showing the role of gastrin and COX-2 in H. pylori-infected patients and their possible association with gastric cancer risk.     

Actualización de la eficacia de la terapia triple para la infección por Helicobacter pylori y de la resistencia a claritromicina en España (2007-2012)

Introduction

Triple therapy, which remains the standard treatment for Helicobacter pylori infection, should be discouraged when its efficacy is lower than 80% or when clarithromycin resistance rates are above 15-20%.

Aim

To update the available evidence on the effectiveness of triple therapy and clarithromycin resistance rates in adults in Spain over the last 6 years.

Methods

A literature search (2007-2012) was conducted in Medline and the abstracts books of the annual meetings of several Spanish gastroenterological and microbiological congresses. The search terms were «Helicobacter pylori», «Spain» and «clarithromycin». Studies were selected if they included triple therapy consisting of a proton pump inhibitor with clarithromycin and amoxicillin or if they analyzed H. pylori clarithromycin susceptibility in treatment-naïve patients.

Results

There were five articles and nine abstracts (3147 patients) on triple therapy, which showed a mean cure rate of 70.8% (95% CI = 66-76%). When stratified by the duration of therapy, the mean cure rates were 68.8% (60-76%) for 7-day regimens and 71.76% (68-78%) for 10-day regimens. For clarithromycin resistance rates, four articles and five abstracts (1709 patients) revealed a mean resistance rate of 18.3% (13-22%).

Conclusions

The efficacy of triple therapy seems to be unacceptable in recent studies conducted in Spain, possibly associated with clarithromcyin resistance rates higher than previously reported.