Lower concentrations of clarithromycin suppress urease activity, motility, and binding to gastric epithelial cells in Helicobacter pylori isolates.

BACKGROUND: Our previous study showed that histological scores of gastric mucosal inflammation and Helicobacter pylori density decreased even in patients who failed to eradicate Helicobacter pylori after antimicrobial therapy including clarithromycin. This may reflect indirect suppressive effects of lower concentrations of clarithromycin on Helicobacter pylori, as suggested in other Gram-negative rod infections. AIMS: To investigate whether clarithromycin suppresses virulence factors of Helicobacter pylori at sub-minimal inhibitory concentration. METHODS: Six clarithromycin-susceptible Helicobacter pylori isolates and 7 clarithromycin-resistant isolates were obtained from patients with peptic ulcer disease. These isolates were analysed for urease activity, motility, and ability to bind to gastric epithelial cells after they were incubated with or without clarithromycin at sub-minimal inhibitory concentrations. RESULTS: Incubation of Helicobacter pylori isolates with clarithromycin at sub-minimal inhibitory concentrations reduced urease activity motility, and binding to gastric epithelial cells in a dose-dependent manner. These findings were observed both in clarithromycin-susceptible and resistant strains. CONCLUSIONS: Suppressive effects of clerithromycin on virulence factors of Helicobacter pylori at sub-minimal inhibitory concentrations may be associated with observed attenuation of gastric inflammation and Helicobacter pylori density in patients who failed in bacterial eradication after triple therapy including clarithromycin.     

Discrepancy between Helicobacter pylori stool antigen assay and urea breath test in the detection of Helicobacter pylori infection

Background. The reference diagnostic methods available for detection of Helicobacter pylori infection are either invasive (histology) or expensive and highly sophisticated (Urea Breath Test). A new enzyme immunoassay, which can be easily performed in any laboratory, has been developed to detect Helicobacter pylori in stool specimens (HpSA - Meridian Diagnostics, Cincinnati, USA). Aim of the study was to compare HpSA to Urea Breath Test.Patients and methods. A total of 125 patients (52 never treated for Helicobacter pylori infection and 73 after Helicobacter pylori eradication therapy) referring to our Department, underwent both tests within two weeks.Results. Contrasting results between the two tests were found in 30% of cases: in 19% of the untreated patients and in 37% of the treated patients (p<0.001). The main discrepancy consisted in positive HpSA associated with negative Urea Breath Test. Mean HpSA value in such conditions was 0.273 optical density, while in patients with both positive tests, it was 1.192 optical density. In untreated, but not in treated patients, raising the HpSA cut off value significantly decreased the percentage of conflicting results.Conclusions. Some disagreement was detected between HpSA and Urea Breath Test results, especially in treated patients. Possible explanations for our findings are a low HpSA cut off value together with the identification of Helicobacter pylori coccoid forms by the immunoassay but not by the urease based Urea Breath Test. The higher percentage of discrepancy detected in treated patients might support this hypothesis.     

Helicobacter pylori and gastric carcinogenesis

Gastric carcinoma is the second leading cause of cancer-related deaths in the world, accounting for more than 700,000 deaths each year. Recent studies have revealed that infection with cagA-positive Helicobacter pylori plays an essential role in the development of gastric carcinoma. The cagA-encoded CagA protein is delivered into gastric epithelial cells via the bacterial type IV secretion system, where it undergoes tyrosine phosphorylation by Src and Abl kinases. Tyrosine-phosphorylated CagA then acquires the ability to interact with and deregulate SHP-2 phosphatase, a bona-fide oncoprotein, deregulation of which is involved in a variety of human malignancies. CagA also binds to and inhibits PAR1b/MARK2 polarity-regulating kinase to disrupt tight junctions and epithelial apical-basolateral polarity. These CagA activities may collectively contribute to the transformation of gastric epithelial cells. Indeed, transgenic expression of CagA in mice results in the development of gastrointestinal and hematological malignancies, indicating that CagA is the first bacterial oncoprotein that acts in mammalian cells. The oncogenic potential of CagA may be further potentiated in the presence of chronic inflammation, which aberrantly induces activation-induced cytidine deaminase (AID), a member of the DNA/RNA-editing enzyme family. Ectopically expressed AID may contribute to H. pylori-initiated gastric carcinogenesis by increasing the risk of likelihood of epithelial cells acquiring mutations in cancer-related genes.     

Helicobacter pylori infection in subjects with acute ischaemic stroke

AIMS: To determine whether infection with Helicobacter pylori is a significant risk factor for stroke. SUBJECTS: A total 467 in-patients with clinical evidence of acute ischaemic stroke and 388 healthy controls with no evidence of cerebrovascular disease. METHODS: This was a case control study. The prevalence of Helicobacter pylori was measured by enzyme-linked immunosorbent assay in stroke patients and controls. A positive titre was defined as >15 U/ml and relationship with circulating plasma fibrinogen and social depravation was expressed using the Townsend Index. RESULTS: There were significantly more Helicobacter pylori positive individuals (274/398 (69%)) in the cases compared to the controls (206/352 (58.5%)). Fibrinogen levels were also significantly higher in Helicobacter pylori positive (mean 4.14, standard deviation 1.33) than negative individuals (mean 3.78, standard deviation 1.28). The association between Helicobacter pylori and stroke was lost in a logistic model controlling for socio-economic status. Furthermore, fibrinogen levels were not associated with Helicobacter pylori status in a linear regression model controlling for socio-economic status. CONCLUSIONS: Infection with Helicobacter pylori is associated with an increased risk of stroke and increased fibrinogen levels but these findings can be attributed to a confounding effect of socio-economic status.     

Change in apoptosis in the gastric surface epithelium and glands after eradication of Helicobacter pylori

BACKGROUND: Change in apoptosis in gastric glands after eradication of Helicobacter pylori has never been reported. AIMS: The purpose of this paper is to investigate the change in apoptosis in gastric glands after eradication of Heliobacter pylori. PATIENTS AND METHODS: We studied 23 Heliobacter pylori-positive patients with duodenal and gastric ulcers, who were monitored for 6-12 months after eradication, and eight controls. Biopsies were taken from the antrum and body. Apoptosis was evaluated immunohistochemically using anti-single stranded DNA antibody. Apoptotic index was calculated by counting immunostained cells in surface epithelial and glandular cells. RESULTS: In the surface epithelium, Apoptotic indexes were significantly higher in patients than in controls. In the upper portion of fundic glands, apoptotic indexes were significantly higher in patients with gastric ulcers (14.2% (9.3, 17.8)) (median (1st quartile, 3rd quartile)) than in controls (8.0% (2.0, 9.0), p < 0.01) and decreased significantly after eradication (3.4% (2.0, 5.3)), p < 0.01). In pyloric glands, apoptotic indexes were no different between patients and controls. In the lower portion of fundic glands, apoptotic indexes were very low, both in patients and in controls. CONCLUSIONS: Our results showed that apoptosis, not only of surface epithelial cells but also of glandular cells in the upper portion of fundic glands, increased in Heliobacter pylori-positive patients with gastric ulcers and decreased to normal levels after eradication of Heliobacter pylori.     

Helicobacter pylori diagnosis in patients with liver cirrhosis

BACKGROUND: In cirrhotics, Helicobacter pylori infection is the major cause of peptic lesions, which are an important cause of upper intestinal haemorrhage in these patients. However, some diagnostic methods are not accurate for H. pylori detection in cirrhotics. AIMS: The study assessed the accuracy of different diagnostic methods for H. pylori detection in cirrhotics with and without gastroduodenal lesions. METHODS: The study population comprised of 53 cirrhotics. All patients underwent upper endoscopy: three biopsies were taken in the antrum and three in the gastric body. Four biopsies were used for Giemsa staining, while two were used for a rapid urease test. A blood sample was obtained for serology using Western blotting, and a [13C]urea breath test was performed in all patients. Histological assessment was regarded as the gold standard for diagnosis of H. pylori infection. RESULTS: H. pylori infection was detected at histological assessment in 28 (52.8%) patients. The [13C]urea breath test, rapid urease test, and serology were positive in 27 (51%) patients, 23 (43.4%) patients, and 34 (64.1%) patients, respectively. Sensitivity and specificity were 92.9 and 96% for the [13C]urea breath test, 78.6 and 96% for the rapid urease test, and 78.6 and 52% for serology. CONCLUSIONS: The [13C]urea breath test is very accurate in cirrhotics, whilst both serology and the rapid urease test give disappointing results.     

Severe acute gastritis associated with Helicobacter pylori infection

We describe the case of a young female referred to our unit because of acute upper abdominal symptoms. Upper gastrointestinal endoscopy showed a gastric picture resembling lymphoma or acute non-steroidal anti-inflammatory drug gastropathy (deep, large and irregular ulcers), but the clinical history and the histological examination of gastric biopsies were consistent only with acute gastritis Helicobacter pylori-correlated. The patient was treated with omeprazole and antibiotics with complete recovery. As the patient's cat had suffered from an acute gastrointestinal distress two weeks earlier, a case of zoonosis was hypothesized and an upper gastrointestinal endoscopy was performed also on the cat. Unfortunately, we were not able to detect Helicobacter pylori in the cat gastric mucosa, but only urease-producing spiral microorganisms. Possible sources of infection and pathogenetic mechanisms of the severe gastritis are discussed.     

Role of Helicobacter pylori infection in pernicious anaemia

Background. Pernicious anaemia is associated with atrophic body gastritis and considered an autoimmune disease. Whether Helicobacter pylori is involved in the induction of pernicious anaemia is uncertain.Aims. To investigate the prevalence of Helicobacter pylori infection in pernicious anaemia patients and to ascertain whether the Helicobacter pylori positive patients had distinctive clinical and gastric morphofunctional characteristics.Patients and Methods. A series of 81 consecutive pernicious anaemia patients underwent serological, functional and endoscopic/histological investigations.Results. A total of 49 (60.5%) patients were Helicobacter pylori-positive (males 61.2% vs females 38.8%). No difference was observed in clinical and morphofunctional characteristics between Helicobacter pylori-positive and negative patients, whereas distinctive functional/histological features between histologically Helicobacter pylori-positive (n=8) and serologically Helicobacter pylori-positive (n=41) cases were detected. In the histologically Helicobacter pylori-positive group, Pepsinogen I was higher [13 [0–58] vs 5 [0–26] ng/ml; P=0.0025]) and positivity for anti-parietal cell antibodies was lower [42.9% vs 76.9, P=0.0867). Antral histological variables of the gastritis score were significantly higher in the histologically Helicobacter pylori-positive than in the serologically Helicobacter pylori-positive patients, but this latter group had a higher score of body atrophy (2.63± 0.12 vs 1.71 ± 0.29; P=0.0051). Body inflammation was also significantly higher in the histologically Helicobacter pylori-positive group (chronic inflammation: 1.43±0.2 vs 1.05±0.06; P=0.0271; inflammation acitivity:: 0.57±0.3 vs 0.15±0.06, P=0.0220). Antral mucosa was normal in 24/41 (58.5%) of the serologically Helicobacter pylori-positive patients, but only in 1/8 (12.5%) of the histologically Helicobacter pylori-positive patients (p=0.232).Conclusions. Almost two thirds of pernicious anaemia patients have evidence of Helicobacter pylori, but only those with an active Helicobacter pylori infection have distinctive functional and histological features. These findings support the hypothesis that Helicobacter pylori infection could play a triggering role in a subgroup of pernicious anaemia patients.     

Treatment of Helicobacter pylori infection. indications and regimens: an update

The management of Helicobacter pylori infection is still surrounded by controversy and uncertainties. Indications and correct application of current regimens for Helicobacter pylori infection are still considered a matter of debate. Regarding indications, only peptic ulcer and mucosa associated lymphoid tissue lymphoma are considered clear indications for treatment. In other conditions, such as atrophic gastritis, post gastric cancer resection, first-degree relatives of gastric cancer patients, dyspeptic patients, patients with gastro-oesophageal reflux disease and non-steroidal anti-inflammatory drug users, the value of Helicobacter pylori eradication is still controversial. The regimens for first-line and second-line treatment of Helicobacter pylori infection have been recommended by the Maastricht 2 Consensus Report. Although all the treatments are considered to be effective, physicians still do not agree on what first-line regimen should be used. Furthermore, a consensus on the duration of the antibiotic treatment is still lacking, although Maastricht guidelines for treatment of Helicobacter pylori infection recommend a one-week therapy. Also regimens, as a third-line treatment, and methods to improve compliance and clinical outcome are still a matter of debate. All these points will be considered in the present review.     

Comparison of two new rapid serology tests for diagnois of Helicobacter pylori infection in Chinese patients

Background. Rapid serology test is a simple and convenient way for diagnosing Helicobacter pylori infection. However, performances of these tests are usually less satisfactory than expected, particularly in developing countries.Aim. To evaluate the performances of two newly developed rapid serology tests for Helicobacter pylori infection.Patients. Consecutive Chinese dyspeptic patients undergoing upper gastrointestinal endoscopy.Methods. Gastric biopsies were obtained from antrum and corpus for rapid urease test and histological examination. Diagnosis of Helicobacter pylori infection was based on two or more positive results in rapid urease test, histology and [¹³C] urea breath test. Patients' sera were tested against two rapid serology tests: ASSURE Hp Rapid Test (Genelabs Diagnostics, Singapore) and SureStep (Applied Biotech, San Diego, CA, USA).Results. A total of 148 patients were evaluated and Helicobacter pylori infection was diagnosed in 78 (53%) patients by gold standard. The sensitivities of ASSURE Hp and SureStep were, respectively, 94% and 71 % (p=0.0003). Specificities of the two test kits were both 90%. The overall accuracy of ASSURE Hp was significantly higher than SureStep (92% versus 80%, P=0.004).Conclusion: Both rapid serology tests appear to be specific in diagnosing Helicobacter pylori infection in the Chinese populations. However, the ASSURE Hp test is more sensitive and accurate than the SureStep test.     

Helicobacter pylori is not a risk factor for hepatic encephalopathy

Background. Helicobacter pylori infection has been described as a risk factor for hepatic encephalopathy in patients with chronic liver disease although the topic remains controversial.Aims. To determine whether Helicobacter pylori infection is an independent predictive factor for encephalopathy in patients with liver cirrhosis.Methods. Clinical, epidemiological, analytical and nutritional parameters of 205 patients were collected. Helicobacter pylori infection was determined by serology. Encephalopathy (grade 11 or higher) was clinically assessed during follow-up. The relationship between each parameter and encephalopathy was analysed by Kaplan-Meier curves and the Log rank test. The most significant parameters underwent multivariate analysis by Cox regression.Results. Twenty-five variables were related to encephalopathy in the bivariate analysis. Multivariate analysis selected five independent factors: previous bouts of encephalopathy (Odds ratio 3.79; 95% confidence interval 1.94–7.38), albumin (Odds ratio 0.86; 95% confidence interval 0.80–0.92), tricipital skin fold (Odds ratio 0.79; 95% confidence interval 0.66–0.95] chronic pulmonary disease (Odds ratio 2.78, 95% confidence interval; 1.31–5.92), and on-going alcoholism (Odds ratio 2.62; 95% confidence interval 1.16-5.88].Conclusions. Helicobacter pylori is not an independent risk factor for hepatic encephalopathy.     

Dyspepsia and Helicobacter pylori infection: a prospective multicentre observational study

OBJECTIVES: Dyspepsia still represents an unsolved clinical enigma. AIM: The aims of this study were to determine whether symptoms and Helicobacter pylori infection are predictors of organic disease in uninvestigated dyspepsia, and if H. pylori eradication improves symptoms in functional dyspepsia. METHODS: An observational study was performed on outpatients with uninvestigated dyspepsia. Symptoms were scored and H. pylori status determined. Patients with functional dyspepsia and H. pylori infection were randomly given either a standard eradicating treatment or a 1-month course of empirical treatment. The latter was also given to functional dyspeptic patients without infection. Symptoms were re-assessed in functional dyspeptic patients at 2- and 6-month follow-up visits. Patients receiving eradicating treatment were re-tested for H. pylori at the 2 month visit. RESULTS: A total of 860 patients were studied and 605 (70.3%) were affected by functional dyspepsia. H. pylori infection was diagnosed in 71.8% of patients with organic dyspepsia and in 65.0% with functional dyspepsia (p=0.053). Male sex, anaemia, smoking habit, age over 45 years, and severe epigastric pain, but not H. pylori infection, were independent predictors of organic disease. Symptoms significantly improved in most functional dyspeptic patients regardless of their H. pylori status and type of treatment. CONCLUSION: H. pylori infection is not a strong predictor of organic disease in uninvestigated dyspepsia. H. pylori eradication is not essential to improve symptoms in functional dyspepsia.     

Hypersecretory duodenal ulcer and Helicobacter pylori infection: for-year follow-up study

Background. About 10% of duodenal ulcer patients are characterized by gastric acid hypersecretion with normal gastrin values. Relapsing duodenal ulcer after Helicobacter pylori cure has been related to high acid output and maintenance antisecretory therapy has been suggested in hypersecretory duodenal ulcer patients. The role of Helicobacter pylori infection and the effects of Helicobacter pylori cure in hypersecretory duodenal ulcer patients still remain to be fully studied.Aim. To study: a) whether gastric acid hypersecretion “per se” is a risk factor for duodenal ulcer recurrence; b) whether maintenance antisecretory therapy is necessary after eradication in hypersecretory duodenal ulcer patients.Patients. The study population comprised 8 hypersecretory duodenal ulcer patients, selected from a population of 79 Helicobacter pylori-positive duodenal ulcer patients.Methods. Hypersecretory duodenal ulcer patients were followed-up for at least 4 years after eradication. Gastric acid secretion was measured again 12 months after Helicobacter pylori eradication. Gastroscopy with histology was performed 3, 6, 12 and 36 months after treatment, ¹³C-urea breath test after 42 months; clinical questionnaires were completed every 6 months.Results. After eradication, despite a not significantly reduced high acid output (median value of basal acid output and pentagastrin-stimulated acid output, respectively, 23.1 mEg/h and 64. 1 mEg/h before treatment vs 16 mEg/h and 49.7 mEq/h 12 months after treatment), all patients were free from symptoms, none of them had duodenal ulcer relapse or complications (7/8 before treatment), or needed antisecretory maintenance therapy, except for one patient taking non-steroidal anti-inflammatory drugs.Conclusions. These findings, obtained in a selected population of hypersecretory duodenal ulcer patients with long-term follow-up, suggest that after successful Helicobacter pylori eradication gastric acid hypersecretion “per se” is not able to determine the recurrence of duodenal ulcer.     

Increased phospholipase activity in Helicobacter pylori strains isolated from patients with gastric carcinoma

PURPOSE: Phospholipase activity, one of Helicobacter pylori pathogenicity factors, has not been investigated enough, so far, although it may induce a remarkable damage to the gastric mucosa. In the present work, we have compared the whole phospholipase activity of H. pylori strains isolated from patients with gastric carcinoma with that of strains isolated from dyspeptic patients without gastric carcinoma. METHODS: We measured the phospholipase activity of one distinct H. pylori colony isolated from each of 10 patients with gastric carcinoma and 10 controls, dyspeptic patients without endoscopic and histological signs of gastric carcinoma. We also determined the phospholipase activity of 20 additional strains isolated from different areas of neoplastic and non-neoplastic tissue of two patients with gastric carcinoma, the cagA and vacA positive G27 and 328 wild strains and their respective vacA and cagA negative isogenic mutants. The whole phospholipase activity of strains was determined by measuring the release of (14)C-labeled palmitic acid from the radioactive l-3-phosphatidylcholine, 1,2-di[1-(14)C]palmiloyl substrate; results were expressed in pmol of palmitic acid per mg of protein. RESULTS: H. pylori strains isolated from patients with gastric carcinoma had levels of phospholipase activity significantly higher than those of strains isolated from controls (99.37 [S.D. 40.45] versus 34.46 [S.D. 16.46], P<0.001). In patients with gastric carcinoma, the mean phospholipase activity of strains isolated from neoplastic tissue was similar to that of strains isolated from non-neoplastic tissues (123.02 [S.D. 44.36] and 115.77 [S.D. 81.48], respectively. Interruption of cagA gene caused a ca. 20% reduction of phospholipase activity (36.38 versus 45.22 of the wild strain); that of vacA caused no reduction of phospholipase activity (26.53 and 25.37 of the wild strain). CONCLUSIONS: The infection by H. pylori strains that produce high levels of phospholipase may increase the risk of developing gastric carcinoma. We hypothesise that indirect products of phospholipase activity, such as prostaglandins, leukotrienes and lysophospholipids, may mediate carcinogenesis.     

A third-line levofloxacin-based rescue therapy for Helicobacter pylori eradication

BACKGROUND: Helicobacter pylori infection persists in a considerable proportion of patients after both first- and second-line current treatments. A standard therapy for re-treatment in such refractory patients is still lacking. This study aimed to evaluate the efficacy of a levofloxacin-amoxycillin combination in patients who previously failed two or more therapeutic attempts. PATIENTS AND METHODS: Consecutive patients with persistent Helicobacter pylori infection were enrolled. Bacterial infection was assessed by rapid urease test and histology on gastric biopsies at endoscopy. Patients were assigned to receive a 10-day triple therapy, comprising rabeprazole 20 mg b.d., levofloxacin 250 mg b.d., and amoxycillin 1 g b.d. Four to 6 weeks after therapy, Helicobacter pylori eradication was assessed by a further endoscopy or 13C urea breath test. RESULTS: Overall, 36 patients were enrolled, but two patients were lost to follow-up. Helicobacter pylori was successfully cured in 30 patients, giving an 83.3% (95% CI=71.2-95.5) and 88.2% (95% CI=77.4-99) eradication rate at intention-to-treat and per protocol analysis, respectively. Compliance was good in all but two patients, who discontinued the treatment at 8 and 6 days, respectively, on account of glossitis. No major side-effects were reported, whilst 7 (20.1%) patients complained of mild side-effects. CONCLUSIONS: This study demonstrates that a 10-day levofloxacin-amoxycillin triple therapy is a safe and successful third-line therapeutic approach for Helicobacter pylori eradication.     

Probiotic intervention decreases serum gastrin-17 in Helicobacter pylori infection

BACKGROUND: Previously we showed that a probiotic combination with L. rhamnosus GG was beneficial as an adjuvant therapy during H. pylori eradication. AIM: To evaluate whether probiotic combination with LGG adheres to the upper gastrointestinal mucosa and modifies H. pylori colonisation and H. pylori induced inflammation. METHODS: Thirteen patients referred for gastroduodenoscopy received a drink consisting of equal doses (2.5x10(9)CFU) of LGG, L. rhamnosus LC705, Propionibacterium freudenreichii JS and Bifidobacterium lactis Bb12 daily. Recovery of probiotics in biopsies (antrum, corpus, duodenum) and faecal samples was evaluated by strain-specific quantitative polymerase chain reaction. H. pylori colonization and gastric inflammation was investigated by urease activity ((13)C-urea breath test), histology and serum pepsinogen I, II and gastrin-17 measurements. RESULTS: Twelve patients were fully investigated; of these three of the patients had LGG adhering to the biopsies at end of the intervention. Other probiotic strains were not detected, even though the recovery of all individual probiotic strains from the faeces was significantly increased (p<0.01). After the treatment, the level of (13)C-urea breath test (p=0.063) and gastrin-17 (p=0.046) decreased. CONCLUSIONS: The decreases in (13)C-urea breath test and gastrin-17 indicate that the probiotic combination exerts a beneficial effect on gastric mucosa in H. pylori infected patients. LGG showed marginal ability to adhere to the upper gastrointestinal tract mucosa.     

Esomeprazole-based therapy in Helicobacter pylori eradication: a meta-analysis

AIM: To perform a systematic review on the efficacy of esomeprazole-based therapies in Helicobacter pylori eradication, and to conduct a meta-analysis comparing the efficacy of esomeprazole and other proton pump inhibitors when co-prescribed with antibiotics. METHODS: Studies evaluating esomeprazole plus antibiotics were considered. Only randomised trials comparing esomeprazole and other proton pump inhibitors with antibiotics, and differing only in the proton pump inhibitor, were included in the meta-analysis. Electronic and manual bibliographical searches were conducted. The percentage (weighted mean) of eradication success was calculated. Meta-analysis was performed combining the odd ratios of the individual studies. RESULTS: Mean cure rates with dual regimens (esomeprazole plus clarithromycin) were 51 and 54%, respectively, by intention-to-treat and by per-protocol. Corresponding figures with triple regimens (esomeprazole plus clarithromycin and either amoxicillin or metronidazole) were 82% (intention-to-treat) and 86% (per-protocol). Four studies were included in the meta-analysis: mean H. pylori eradication rates (intention-to-treat) with esomeprazole plus antibiotics was 85 and 82% when omeprazole was used (odds ratio = 1.19; 95% confidence interval = 0.81-1.74), results being statistically homogeneous. When subanalysis included only high quality studies, the odds ratio for this comparison was closer to one (1.08; 95% confidence interval = 0.4-1.47) and results were more homogeneous. CONCLUSIONS: Esomeprazole-based triple therapy is highly effective for the eradication of H. pylori infection and offers comparable efficacy to omeprazole-based therapy.     

Effect of Helicobacter pylori infection on gastric cell proliferation and genomic instablity in a paediatric population of Southern Italy

Background. The incidence of gastric cancer is high in areas with a high prevalence of Helicobacter pylori infection. Cell transformation and tumour progression occur over a long period of time and markers of genomic instability usually precede morphological changes.Aim. To evaluate the effect of Helicobacter pylori infection on cell proliferation, DNA status and oncogene expression in children.Patients and Methods. Morphometric and immunohistochemical techniques were used to analyse DNA content, p53 and c-myc oncogene expression and cell proliferation on gastric biopsies of 53 children (27 Helicobacter pylori-negative and 26 Helicobacter pylori-positive).Results. Gastric mucosa was normal in 11 % of Helicobacter pylori-positive and in 33% of Helicobacter pylori-negative subjects. Most children had chronic non-atrophic gastritis regardless of Helicobacter pylori infection, and only a minority of children affected by Helicobacter pylori had mild atrophic gastritis. Cell proliferation was significantly higher in children with Helicobacter pylori-positive gastritis than in those with Helicobacter pylori-negative gastritis. No metaplasia, dysplasia, p53 overexpression or altered DNA content was found in any child. Interestingly, 46% of children with and 29% without Helicobacter pylori infection had c-myc overexpression closely related to the cell proliferation rate.Conclusion. Helicobacter pylori infection in children may coexist with a normal gastric mucosa, and it is not associated with genomic instability markers in cases of chronic gastritis.     

Increased prevalence of Helicobacter pylori in patients with diabetes mellitus

BACKGROUND: Whilst upper gastrointestinal disturbances are frequently observed in patients with diabetes mellitus, little is known about the prevalence of Helicobacter pylori infection and peptic disease in these patients. AIM: To evaluate prevalence of Helicobacter pylori infection and peptic disease lesions in diabetics with dyspeptic symptoms. PATIENTS AND METHODS: Study population comprises 74 consecutive diabetes mellitus patients with dyspepsia and 117 consecutive non diabetic dyspeptic patients. Upon enrolment, each patient completed an interview screening questionnaire to obtain information concerning presence and severity of dyspepsia. All patients underwent upper gastrointestinal endoscopy with biopsy specimens being collected from gastric antrum and body Helicobacter pylori was evaluated in each patient by rapid urease test and histology (Giemsa). Gastritis was classified according to the Sydney System. Statistical analysis was performed by chi-square, Fisher exact or t test and logistic regression analysis. A p value <0.05 was considered significant. RESULTS: Prevalence of Helicobacter pylori infection was found to be significantly higher in diabetics than in controls. The prevalence rate of endoscopic lesions was comparable in the two groups, but the association between endoscopic lesions and Helicobacter pylori infection was significantly higher in diabetics. Overall, the presence of chronic gastritis, both non atrophic and atrophic, as well as intestinal metaplasia were comparable in the two groups of patients, whilst the association between chronic gastritis and Helicobacter pylori infection or gastritis activity were significantly higher in diabetics. In neither group, was any correlation found between severity of dyspepsia and presence of endoscopic lesions, chronic gastritis or Helicobacter pylori infection. CONCLUSIONS: These data show a higher prevalence of Helicobacter pylori infection in diabetes mellitus patients with dyspepsia. Helicobacter pylori infection was significantly associated both with the presence of endoscopic lesions and chronic gastritis in diabetic patients, but not in the controls.