Helicobacter pylori infection is associated with gallstones: Epidemiological survey in China

AIM: To elucidate the prevalence and risk factors for gallstones, primarily focusing on Helicobacter pylori(H. pylori) infection. METHODS: A total of 10016 Chinese subjects, who had undergone physical examination, fasting 13 C urea breath test and abdominal ultrasonography, had sufficient blood test data, and had finished a questionnaire, were included in this cross-sectional study. Participants(n = 1122) who had previous eradication of H. pylori were studied separately. RESULTS: Gallstones were discovered in 9.10% of men and 8.58% of women, with no significant sex difference. Multivariate analyses displayed that age, aspartate aminotransferase, total cholesterol, H. pylori infection, hepatitis C virus(HCV) infection, and fattyliver had a significant association with gallstones(P 0.05). Successive multiple logistic regression analysis including index of odds ratio(OR) and standardized coefficient(β) indicated that older age(OR/β = 1.056/0.055), H. pylori infection(OR/β = 1.454/0.109), HCV infection(OR/β = 1.871/0.123), and fatty liver(OR/β = 1.947/0.189) had a significant positive association with gallstones. After age stratification, H. pylori infection and fatty liver still had a significant positive association with gallstones in any age-specific groups, whereas HCV infection had a significant positive association in patients aged 40 years. The prevalence of gallstones among H. pylori-positive, H. pylori-eradicated, and H. pylori-negative subjects was 9.47%, 9.02%, and 8.46%, respectively. The matched analysis showed that gallstones among H. pylori eradicated subjects was significantly lower compared with H. pylori-positive subjects(P 0.05).CONCLUSION: H. pylori infection and fatty liver have a significant positive association with gallstones. H. pylori eradication may lead to prevention of gallstones.     

Association between Helicobacter pylori Seropositivity and the Coronary Artery Calcium Score in a Screening Population

Background/Aims

Helicobacter pylori causes numerous extragastric manifestations, including coronary heart disease. The coronary artery calcification (CAC) score, measured using computed tomography (CT) has been used as a screening test for coronary atherosclerosis. This study investigated the association between H. pylori seropositivity and CAC scores in a screening population.

Methods

Patients who underwent a health checkup between October 2003 and July 2007 and who did not have a history of ischemic heart disease were enrolled in the study. Subjects were screened with a multidetector CT scan to determine the CAC score and for anti-H. pylori antibody immunoglobulin G; traditional risks for coronary heart disease were evaluated using a structured questionnaire, anthropometric measurements, and laboratory tests.

Results

Of the 2,029 subjects enrolled (1,295 males), 1,214 (59.8%) subjects were H. pylori positive and 815 were H. pylori negative. There were no significant differences in the baseline characteristics of the seropositive and seronegative patients. When the CAC presence or absence scores were considered, multivariate analysis revealed that H. pylori seropositivity was statistically associated with the presence of CAC and that this association was stronger in the mild CAC score category.

Conclusions

H. pylori seropositive patients are at a higher risk for coronary atherosclerosis regardless of traditional cardiovascular risk factors. This association is particularly applicable for early coronary atherosclerosis.     

Sero-prevalence of Helicobacter pylori infection among asymptomatic healthy Omani blood donors

Objective

To investigate the prevalence of Helicobacter pylori (H. pylori) infection, a cross-sectional epidemiological study, based on the age and gender-specific seroprevalence of H. pylori antibodies in asymptomatic healthy Omani blood donors attending the SQUH blood bank.

Methods

Analysis of the sera from 133 apparently healthy subjects, based on the serological determination of the IgM, IgG and IgA antibodies against H. pylori, was carried out using a commercially available kit ELISA (NovaLisa, NovaTec, Germany). While the presence of H. pylori-specific IgG antibodies is the marker for a “chronic” infection with this pathogen. Therefore, there was no indicator of the time of acquisition of the infection. However, the H. pylori-specific IgM antibody was a more specific marker for a recently acquired infection with H. pylori.

Results

Of the 133 subjects, there were 100 (74%) males and 33 (26%) females. The age range was 15 to 50 years with a mean of 25.75±3.75 years. The overall prevalence of H. pylori infection in our study was 69.5%. The overall seroprevalence was found to be increased 69%-86% with age. Subjects between 15–20 years of age showed 71% seroprevalence, while those between 21–40 years showed gradual increase (63%–70%) with age and reached up to 87% in subjects between 41–50 years of age. A significant inverse association was found between sex and age groups. This is when each age group was examined individually; a higher positive percentage of H. pylori antibodies increasing with age was seen in males between 21–40 years of age group in comparison to the females of the same age group. Male subjects with age group between 21 to 40 years were found to have a significant seropositivity compared to the female subjects within the same group. This may reflect how frequent were the male subjects being exposed to the outer environment and their conduct than the females in this society like Oman.

Conclusions

The seropositivity of H. pylori is moderately higher between ages of 21 to 30 more than any other age group.     

Sero-prevalence and factors associated with Helicobacter pylori infection in Eastern Sudan

Objective

To investigate the prevalence of Helicobacter pylori (H. pylori) among patients with dyspepsia and to evaluate the correlation between H. pylori infection and socio-demographic factors.

Methods

This cross-sectional hospital-based study, which ran from June to August 2012, determined seroprevalence of H. pylori among adult patients in Eastern Sudan. The presence of H. pylori was determined using ELISA.

Results

A total of 225 adult Sudanese patients were enrolled in the study. Of these, 148 (65.8%) tested positive for H. pylori. In logistic regression analysis, rural residency (OR=3.933, CI=1.337-11.26, P=0.01) was the only socio-demographic factor that was associated with H. pylori infection. The most common symptoms among seropositive patients were heartburn (OR=30.442, CI=9.478-97.776, P≤0.001) and/or epigastria pain (OR=28.225, CI=4.365-182.508, P≤0.001).

Conclusions

Clinical suspicion can facilitate the detection of H. pylori among patients with dyspeptic symptoms in a geographic area with high prevalence of H. pylori infection.     

Helicobacter pylori seropositivity in patients with acute coronary syndromes

The aim of this study was to investigate the seroprevalence of Helicobacter pylori (HP) in patients with coronary atherosclerosis and acute coronary syndromes. We enrolled 152 patients (group I, 73 patients with acute coronary syndrome; group II, 79 patients with chronic stable angina) and 22 control subjects. An enzyme-linked immunosorbent assay for immunoglobulin (Ig) G test for HP diagnosis was used on all enrolled subjects. C-reactive protein (CRP) was also measured in all patients as an inflammatory marker. Seropositivity rates for HP were significantly higher in patients with coronary artery disease than in controls (80.2% versus 54.5%; P < 0.05). Although CRP level was significantly higher in group I than in group II (1.72 ± 2.89 mg/dl versus 0.53 ± 0.63 mg/dl, P < 0.0001), HP infection rates were similar between groups (86.3% versus 74.6%, P > 0.05). Infection with HP may influence atherogenesis through low-grade, persistent inflammatory stimulation. However, our data show evidence of increased systemic inflammation in patients with acute coronary syndrome, which was unrelated to an increased HP seropositivity.     

Helicobacter pylori eradication in patients with chronic immune thrombocytopenic purpura

AIM:To assess the effect of Helicobacter pylori(H.pylori)eradication on platelet counts in patients with chronic immune thrombocytopenic purpura(cITP).METHODS:A total of 36 cITP patients were included in the study.The diagnosis of H.pylori was done by rapid urease test and Giemsa staining of the gastric biopsy specimen.All H.pylori positive patients received standard triple therapy for 14 d and were subjected for repeat endoscopy at 6 wk.Patients who continued to be positive for H.pylori on second endoscopyreceived second line salvage therapy.All the patients were assessed for platelet response at 6 wk,3rd and 6th months.RESULTS:Of the 36 patients,17 were positive for H.pylori infection and eradication was achieved in16 patients.The mean baseline platelet count in the eradicated patients was 88615.38±30117.93/mm3and platelet count after eradication at 6 wk,3 mo and6 mo was 143230.77±52437.51/mm3(P=0.003),152562.50±52892.3/mm3(P=0.0001),150187.50±41796.68/mm3(P=0.0001)respectively and in the negative patients,the mean baseline count was71000.00±33216.46/mm3 and at 6 wk,3rd and 6th month follow up was 137631.58±74364.13/mm3(P=0.001),125578.95±71472.1/mm3(P=0.005),77210.53±56892.28/mm3(P=0.684)respectively.CONCLUSION:Eradication of H.pylori leads to increase in platelet counts in patients with cITP and can be recommended as a complementary treatment with conventional therapy.     

Pseudomembranous colitis associated with a triple therapy for Helicobacter pylori eradication

Helicobacter pylori(H.pylori)is one of the most common chronic bacterial infections in humans,affecting half of world’s population.Therapy for H.pylori infection has proven to be both effective and safe.The oneweek triple therapy including proton pump inhibitor,clarithromycin,and amoxicillin or metronidazole is still recommended as a first-line treatment to eradicate H.pylori infection in countries with low clarithromycin resistance.Generally,this therapy is well-tolerated,with only a few and usually minor side effects.However,rare but severe adverse effects such as pseudomembranous colitis have been reported,Clostridium difficile(C.difficile)infection being the main causative factor in all cases.We report the cases of two women who developed pseudomembranous colitis after a 1-wk triple therapy consisting of pantoprazole 20 mg bid,clarithromycin 500 mg bid,and amoxicillin 1 g bid to eradicate H.pylori infection.A limited colonoscopy showed typical appearance of pseudomembranous colitis,and the stool test for C.difficile toxins was positive.Rapid resolution of symptoms and negative C.difficile toxins were obtained in both patients with oral vancomycin.No relapse occurred during a four and eleven-month,respectively,follow up.These cases suggest that physicians should have a high index of suspicion for pseudomembranous colitis when evaluate patients with diarrhea following H.pylori eradication therapy.     

Helicobacter pylori infection is not associated with nonalcoholic fatty liver disease

AIM: To determine whether Helicobacter pylori(H. pylori) infection confers a higher risk of Nonalcoholic fatty liver disease(NAFLD).METHODS: Healthy people who underwent health screening were analyzed retrospectively. Inclusion criteria were age ≥ 20 years, history of H. pylori infection, and recorded insulin level. Participants were classified as H. pylori positive or negative according to 13 C urea breath tests. NAFLD was defined using the hepatic steatosis index(HSI) and NAFLD liver fat score(NAFLD-LFS). Those with an HSI 36 or NAFLD-LFS -0.640 were considered to have NAFLD. Multivariable logistic regression was performed to identify risk factors for NAFLD.RESULTS: Three thousand six hundred and sixtythree people were analyzed and 1636(44.7%) were H. pylori positive. H. pylori infection was associated with older age, male gender, hypertension, higher body mass index, and a dyslipidemic profile. HSI differed significantly between H. pylori positive and negative subjects(median 33.2, interquartile range(IQR) 30.0-36.2 for H. pylori-positive vs median 32.6, IQR 29.8-36.0 for negative participants, P = 0.005), but NAFLD-LSF did not [median-1.7, IQR-2.4--0.7 vs median-1.8, IQR-2.4-(-0.7), respectively, P = 0.122]. The percentage of people with NAFLD did not differbetween infected and uninfected groups: HIS, 26.9% vs 27.1%, P = 0.173; NAFLD-LFS, 23.5% vs 23.1%, P = 0.778. H. pylori infection was not a risk factor, but C-reactive protein concentration and smoking were significant risk factors for NAFLD.CONCLUSION: H. pylori infection is not a risk factor for NAFLD as indicated by HSI or NAFLD-LFS. Prospective, large-scale studies involving liver biopsies should be considered.     

Helicobacter pylori associated gastric intestinal metaplasia: Treatment and surveillance

Gastric cancer(GC) is one of the leading causes of cancer related death in the world, particularly in East Asia. According to the Correa's cancer cascade, noncardia GC is usually developed through a series of mucosal changes from non-atrophic gastritis to atrophic gastritis(AG), intestinal metaplasia(IM), dysplasia and adenocarcinoma. Atrophic gastritis and IM are therefore generally considered to be pre-neoplastic gastric lesions. Helicobacter pylori(H. pylori) infection is an important initiating and promoting step of this gastric carcinogenesis cascade. Emerging long-term data showed that eradication of H. pylori reduced the risk of subsequent cancer development. It however remains confusing whether eradication of the bacterium in individuals with pre-neoplastic gastric lesions could regress these changes as well as in preventing cancer. Whilst H. pylori eradication could likely regress AG, the presence of IM may be a point of no return in this cascade. Hence, surveillance by endoscopy may be indicated in those with extensive IM or those with incomplete IM, particularly in populations with high GC risk. The optimal interval and the best tool of surveillance endoscopy remains to be determined in future studies.     

Antibiotics resistance rate of Helicobacter pylori in Bhutan

AIM:To survey the antibiotic resistance pattern of Helicobacter pylori(H.pylori)strains isolated from Bhutanese population.METHODS:We isolated 111 H.pylori strains from the gastric mucosa of H.pylori-infected patients in Bhutan in 2010.The Epsilometer test was used to determine the minimum inhibitory concentrations(MICs)of amoxicillin(AMX),clarithromycin(CLR),metronidazole(MNZ),levofloxacin(LVX),ciprofloxacin(CIP),and tetracycline(TET).RESULTS:Nineteen of the isolated H.pylori strains were susceptible to all antibiotics tested.The isolated strains showed the highest rate of antibiotic resistance to MNZ(92/111,82.9%).Among the 92 MNZresistant strains,74 strains(80.4%)showed high-level resistance(MIC≥256 g/mL).Three strains were resistance to LVX(2.7%).These strains were also resistance to CIP.None of the strains showed resistance to CLR,AMX and TET.CONCLUSION:CLR-based triple therapy is a more effective treatment approach over MNZ-based triple therapy for H.pylori infection in Bhutan.     

CpG island methylator phenotype and Helicobacter pylori infection associated with gastric cancer

AIM:To investigate the association between the CpG island methylator phenotype(CIMP) and serum Helicobacter pylori(H.pylori) levels for clinical prediction of gastric cancer(GC) progression.METHODS:We analyzed the serum CIMP status of 75 patients with GC using a methylation marker panel and a methylation-specific polymerase chain reaction.Serum samples from 40 healthy persons were examined at the same time.The genes examined were APC,WIF-1,RUNX-3,DLC-1,SFRP-1,DKK and E-cad.H.pylori infection in serum was assayed with an anti-H.pylori immunoglobulin G antibody test and a rapid urease test.RESULTS:The frequencies of high-level methylation in GC tissues for the seven genes were:48% for APC,57.33% for WIF-1,56% for RUNX-3,50.67% for DLC-1,52% for SFRP-1,54.67% for DKK,and 48% for E-cad.The frequencies in GC serum were 30.67% for APC,34.67% for WIF-1,37.33% for RUNX-3,29.33% for DLC-1,33.33% for SFRP-1,32% for DKK,and 26.67% for E-cad.CIMP+(defined as ≥ 3 methylated genes) was associated with 47(62.67%) GC tissue samples and 44(58.67%) GC serum samples.CIMP+ was not associated with non-neoplastic mucosal tissues or the serum of healthy persons.Of the 75 GC cases,51(68%) were H.pylori +,and 24(32%) were H.pylori-.Of the 51 H.pylori + cases,36 were CIMP+ and 15 were CIMP-.In contrast,for the 24 H.pylori-cases,11 were CIMP+,and 13 were CIMP-.The difference was significant between the H.pylori + and H.pylori-groups(χ 2 = 4.27,P 0.05).Of the 51 H.pylori + GC patients,34 were CIMP+ and 17 were CIMP-,while among the 24 H.pylori-GC cases,10 were CIMP+ and 14 were CIMP-.The difference was significant between the H.pylori+ and H.pylori-groups(χ 2 = 4.21,P 0.05).A 2-year follow-up showed significant difference in the rates of metastasis and recurrence between H.pylori +/CIMP+ cases and the H.pylori +/CIMP-cases or CIMP-cases associated with H.pylori assayed in serum(P 0.05).However,there were no significant differences in survival rates between the two groups.CONCLUSION:H.pylori +/CIMP+ cases are associated with higher rates of metastasis and recurrence than H.pylori +/CIMP-cases.Serum may be useful for examining CIMP status.     

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.     

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 in patients with selective immunoglobulin E deficiency

AIM: To investigate the prevalence and clinical characteristics of Helicobacter pylori(H.pylori)-infected dyspeptic patients with selective immunoglobulin E deficiency(IgE d).METHODS: All individuals who underwent serum totalimmunoglobulin E(Ig E) measurement at the Leumit Healthcare Services(Israel) in 2012 were identified in an electronic database search(n = 18487).From these,selected case group subjects were ≥ 12 years of age and had serum total Ig E 2 k IU/L(n = 158).The control group was selected from a random sampling of the remaining subjects ≥ 12 years of age to obtain a case-control ratio of 1:20(n = 3160).Dyspeptic diseases,diagnosed no more than 5 years before serum total Ig E testing,were identified and retrieved from the electronic database using specific International Classification of Diseases diagnostic codes.Results of C13-urea breath tests were used to identify subjects infected with H.pylori.Categorical variables between case and control subjects were analyzed using Fisher's exact tests,whereas continuous variables were analyzed using χ2 tests.RESULTS: Dyspepsia was present in 27.2%(43/158) of case subjects and 22.7%(718/3160) of controls.Of these,significantly more case subjects(32/43,74.4%) than controls(223/718,31.1%) were positive for H.pylori(P 0.01).Esophagogastroduodenoscopy was performed in 19 case and 94 control subjects,revealing that gastritis was more prevalent in IgE d case subjects than in controls(57.9% vs 29.8%,P 0.05).Furthermore,a significantly greater proportion of case subjects presented with peptic duodenal ulcers(63.2% vs 15.9%,P 0.01).Histopathologic examination showed marked chronic inflammation,lymphoid follicle formation and prominent germinal centers,with polymorphonuclear cell infiltration of gastric glands,that was similar in case and control biopsy tissues.Finally,Ig Ed case subjects that underwent esophagogastroduodenoscopy were more likely to exhibit treatment-refractory H.pylori infections that require second-line triple antibiotic therapy(47.4% vs 11.7%,P 0.01).CONCLUSION: IgE d is associated with higher rates ofH.pylori-associated gastritis and peptic duodenal ulcers.     

Gastric precancerous lesions are associated with gene variants in Helicobacter pylori -susceptible ethnic Malays

AIM: To identify genes associated with gastric pre-cancerous lesions in Helicobacter pylori (H. pylori )susceptible ethnic Malays. METHODS: Twenty-three Malay subjects with H. pylori infection and gastric precancerous lesions identified during endoscopy were included as "cases". Thirtyseven Malay subjects who were H. pylori negative and had no precancerous lesions were included as "controls". Venous blood was collected for genotyping with Affymetrix 50K Xba1 kit. Genotypes with call rates < 90% for autosomal single nucleotide polymorphisms (SNPs) were excluded. For each precancerous lesion, associated SNPs were identified from Manhattan plots, and only SNPs with a χ2 P value < 0.05 and Hardy Weinberg Equilibrium P value > 0.5 was considered as significant markers. RESULTS: Of the 23 H. pylori -positive subjects recruited, one sample was excluded from further analysis due to a low genotyping call rate. Of the 22 H. pylori positive samples, atrophic gastritis only was present in 50.0%, complete intestinal metaplasia was present in 18.25%, both incomplete intestinal metaplasia and dysplasia was present in 22.7%, and dysplasia only was present in 9.1%. SNPs rs9315542 (UFM1 gene), rs6878265 (THBS4 gene), rs1042194 (CYP2C19 gene) and rs10505799 (MGST1 gene) were significantly associated with atrophic gastritis, complete intestinal metaplasia, incomplete metaplasia with foci of dysplasia and dysplasia, respectively. Allele frequencies in "cases" vs "controls" for rs9315542, rs6878265, rs1042194 and rs10505799 were 0.4 vs 0.06, 0.6 vs 0.01, 0.6 vs 0.01 and 0.5 vs 0.02, respectively. CONCLUSION: Genetic variants possibly related to gastric precancerous lesions in ethnic Malays susceptible to H. pylori infection were identified for testing in subsequent trials.     

Helicobacter pylori infection in older people

Since the discovery of Helicobacter pylori(H.pylori)infection as the major cause of gastroduodenal disorders three decades ago,H.pylori has been the focus of active research and debate in the scientific community.Its linkage to several diseases,such as peptic ulcer disease,gastritis and gastric malignancy is incontestable.In particular,it has been noticed that,as the aged population is increasing worldwide,older people are at increased risk of developing several gastroduodenal diseases and related complications.At the same time,gastric cancer is definitely more frequent in elderly than in adult and young people.In addition,it has been showed that peptic ulcer and related complications occur much more commonly in aged individuals than in young people,resulting in a significantly higher mortality.Although this infection plays a crucial role in gastrointestinal disorders affecting all age groups and in particular older people,only a few studies have been published regarding the latter.This article presents an overview of the epidemiology,diagnosis,clinical manifestations and therapy of H.pylori infection in elderly people.     

Vaccine against Helicobacter pylori : Inevitable approach

Over three decades have passed since the discovery of Helicobacter pylori(H. pylori), and yet many questions about its treatment remain unanswered. For example, there is no certainty regarding continued use of current antibiotic therapy against H. pylori. The bad news is that even combined regimens are also unable to eradicate bacterial colonization. The worst problem with H. pylori chemotherapy is that even if we identify the most successful regimen, it cannot eliminate the risk of re-infection. This problem is further complicated by the fact that clinicians have no information as to whether probiotics are useful or not. Moreover, to date, we have no large scale produced vaccine effective against H. pylori. Due to the relatively rapid and abundant dissemination of guidelines globally reported concerning management of gastric cancer prevention and therapeutic regimens, clinicians may choose a vaccine as better effective weapon against H. pylori. Therefore, a radical shift in adopted strategies is needed to guide ultimate decisions regarding H. pylori management. In light of failures in vaccine projects, we should identify better vaccine design targeting conserved/essential genes. The unique character and persistence of H. pylori pose obstacles to making an effective vaccine. Preferably, in developing countries, the best reasonable and logical approach is to recommend prophylactic H. pylori vaccine among children as an obligatory national program to limit primary colonization. Trying to produce a therapeutic vaccine would be postponed until later. In reality, we should not forget to prescribe narrow spectrum antibiotics. In the current review, I draw a route to define the best adopted strategy against this rogue bacterium.     

Helicobacter pylori and serum kynurenine-tryptophan ratio in patients with colorectal cancer

AIM: To evaluate how Helicobacter pylori(H. pylori) is able to evade the immune response and whether it enhances systemic immune tolerance against colorectal cancer.METHODS: This prospective randomized study involved 97 consecutive colorectal cancer patients and 108 cancer-free patients with extra-digestive diseases. Colorectal cancer and cancer-free patients were assigned into subgroups according to H. pylori Ig G seropositivity. Exposure to H. pylori was determined by Ig G seropositivity which was detected by enzyme linked immunoassay(ELISA). Serum neopterin levels were measured by ELISA. Serum tryptophan, kynurenine, and urinary biopterin concentrations were measured by high performance liquid chromatography. Serum nitrite levels were detected spectrophotometrically. Serum indoleamine 2,3-dioxygenase activity was estimated by the kynurenine to tryptophan ratio and by assessing the correlation between serum neopterin concentrations and the kynurenine to tryptophan ratio. The frequencies of increased serum kynurenine to tryptophan ratio of H. pylori seronegative and seropositive colorectal cancer subgroups were estimated by comparing them with the average kynurenine to tryptophan ratio of H. pylori seronegative tumor-free patients.RESULTS: Compared with respective controls, in both H. pylori seronegative and seropositive colorectal cancer patients, while serum tryptophan levels were decreased(controls vs patients; seronegative: 20.37 ± 0.89 μmol/L vs 15.71 ± 1.16 μmol/L, P < 0.05; seropositive: 20.71 ± 0.81 μmol/L vs 14.97 ± 0.79 μmol/L, P < 0.01) the kynurenine to tryptophan ratio was significantly increased(controls vs patients; seronegative: 52.85± 11.85 μmol/mmol vs 78.91 ± 8.68 μmol/mmol, P < 0.01, seropositive: 47.31 ± 5.93 μmol/mmol vs 109.65 ± 11.50 μmol/mmol, P < 0.01). Neopterin concentrations in cancer patients were significantly elevated compared with controls(P < 0.05). There was a significant correlation between serum neopterin levels and kynurenine/tryptophan in control and colorectal cancer patients groups(r s = 0.494, P = 0.0001 and r s= 0.293, P = 0.004, respectively). Serum nitrite levels of H. pylori seropositive cancer cases were significantly decreased compared with seropositive controls(controls vs patients; 26.04 ± 2.39 μmol/L vs 20.41 ± 1.48 μmol/L, P < 0.05) The decrease in the nitrite levels of H. pylori seropositive cancer patients may be attributed to excessive formation of peroxynitrite and other reactive nitrogen species.CONCLUSION: A significantly high kynurenine/tryptophan suggested that H. pylori may support the immune tolerance leading to cancer development, even without an apparent upper gastrointestinal tract disease.     

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.     

Optimal initiation of Helicobacter pylori eradication in patients with peptic ulcer bleeding

AIM:To evaluate when Helicobacter pylori(H.pylori)eradication therapy(ET)should be started in patients with peptic ulcer bleeding(PUB).METHODS:Clinical data concerning adults hospitalizedwith PUB were retrospectively collected and analyzed.Age,sex,type and stage of peptic ulcer,whether endoscopic therapy was performed or not,methods of H.pylori detection,duration of hospitalization,and specialty of the attending physician were investigated.Factors influencing the confirmation of H.pylori infection prior to discharge were determined using multiple logistic regression analysis.The H.pylori eradication rates of patients who received ET during hospitalization and those who commenced ET as outpatients were compared.RESULTS:A total of 232 patients with PUB were evaluated for H.pylori infection by histology and/or rapid urease testing.Of these patients,53.7%(127/232)had confirmed results of H.pylori infection prior to discharge.In multivariate analysis,duration of hospitalization and ulcer stage were factors independently influencing whether H.pylori infection was confirmed before or after discharge.Among the patients discharged before confirmation of H.pylori infection,13.3%(14/105)were lost to follow-up.Among the patients found to be H.pylori-positive after discharge,41.4%(12/29)did not receive ET.There was no significant difference in the H.pylori eradication rate between patients who received ET during hospitalization a n d t h o s e w h o c o m m e n c e d E T a s o u t p a t i e n t s[intention-to-treat:68.8%(53/77)vs 60%(12/20),P=0.594;per-protocol:82.8%(53/64)vs 80%(12/15),P=0.723].CONCLUSION:Because many patients with PUB who were discharged before H.pylori infection status was confirmed lost an opportunity to receive ET,we should confirm H.pylori infection and start ET prior to discharge.