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Who should be treated for Helicobacter pylori infection? A review of consensus conferences and guidelines.

The publication of the National Institutes of Health Consensus Development Conference guidelines on management of Helicobacter pylori infection in 1994 set a precedence. At present, at least eight European countries have produced national guidelines, and, more recently, the European Helicobacter pylori Study Group also outlined guidelines based on the strength of available evidence. It is generally agreed that H. pylori should be eradicated in peptic ulcer disease. In nonsteroidal anti-inflammatory drug (NSAID)-related ulcers, most countries that considered the issue suggested discontinuing NSAIDs when possible and eradicating H. pylori. The prophylactic eradication of H. pylori was not recommended. A number of panels felt that there was not enough evidence available to recommend eradication of H. pylori in functional dyspepsia, whereas other groups felt that nonulcer dyspepsia, particularly after investigation and with severe or recurrent symptoms, was an indication for eradication therapy. Other conditions (i.e., gastroesophageal reflux disease [GERD] and mucosa-associated lymphoid tissue [MALT] lymphoma) have emerged in this short time as possible indications for H. pylori eradication. There is no evidence that H. pylori infection has a role in the pathogenesis of GERD, but there is evidence suggesting that patients with H. pylori infection who require long-term acid suppression may be at risk of developing atrophic gastritis. The European Helicobacter pylori Study Group has suggested that eradication therapy should be offered to infected family members of patients with gastric cancer. It also recommended that eradication therapy was "strongly recommended" on the basis of "supportive" evidence in gastritis with severe abnormalities and after early resection of early gastric cancer. An "uncertain" recommendation with "equivocal" evidence was given for asymptomatic subjects, extra-alimentary tract disease, the prevention of gastric cancer in the absence of risk factors, and in pediatric patients with recurrent abdominal pain. Despite considerable advances, further research studies are needed to provide definite direction for the treatment of many conditions.

Consensus Statements as Topic↗

Mice lacking secretory phospholipase A2 show altered apoptosis and differentiation with Helicobacter felis infection.

BACKGROUND & AIMS: Infection with Helicobacter pylori uniformly leads to a chronic superficial gastritis that may progress to atrophic gastritis, a premalignant process. A mouse model of Helicobacter felis infection was used to study possible genetic determinants of the response to infection. METHODS: Three inbred mouse strains with known secretory phospholipase A2 (sPLA2) genotypes [BALB/c (+/+), C3H/HeJ (+/+), and C57BL/6 (-/-)] were orally infected with H. felis and examined longitudinally using routine histology, immunocytochemistry, electron microscopy, proliferating cell nuclear antigen, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling, and Northern and Western blot studies. RESULTS: Only the C57BL/6 strain showed increased gastric fundic proliferation and apoptosis in response to infection. In addition, the C57BL/6 mouse showed a marked loss of parietal and chief cells, along with a marked expansion of an aberrant gastric mucous cell lineage that stained positive for spasmolytic polypeptide. In contrast, no significant change in these cell types was observed in BALB/c and C3H/HeJ strains. Increased expression of sPLA2 was observed in BALB/c and C3H/HeJ after H. felis infection, whereas sPLA2 expression was absent in C57BL/6 mice. CONCLUSIONS: H. felis infection leads to increased apoptosis and altered cellular differentiation in the C57BL/6 mouse, a strain that lacks gastric sPLA2 expression. Because sPLA2 has been identified recently as the MOM1 (modifier of MIN) locus that influences polyp formation in the colon, these studies suggest that sPLA2 may also influence the gastric epithelial response to Helicobacter infection.

Animals↗

[Chronic urticaria and Helicobacter pylori].

BACKGROUND AND OBJECTIVE: We intended to analyze the influence of Helicobacter pylori eradication on the clinical evolution of patients with chronic idiopathic urticaria. PATIENTS AND METHOD: The evolution of dermatological symptoms after eradication was studied in a group of 55 patients previously diagnosed with chronic idiopathic urticaria who were infected by Helicobacter pylori. RESULTS: There was a partial or complete improvement in 74.6% (CI 95%, 61-85%) of studied patients. We could not demonstrate a statistically significant influence of sex, age or endoscopic lesions on the clinical evolution of urticaria after eradication. CONCLUSIONS: These results suggest a possible usefulness of Helicobacter pylori eradication in some patients with chronic idiopathic urticaria. Controlled and randomized studies are necessary to confirm it.

Adolescent↗

Helicobacter sp. recovered from drinking water biofilm sampled from a water distribution system.

Workers examining the transmission route(s) and reservoir(s) of infection for Helicobacter pylori have postulated several environmental reservoirs for the organism, including water. Such work has, to date, concentrated on the bulk liquid in drinking water systems rather than on biofilms. Previous investigations by the authors have suggested biofilms in water distribution systems are a possible reservoir of infection. This current study comprised of an analysis of a section of cast iron mains distribution pipe removed from an urban environment in the north-east of Scotland during routine maintenance work. Immediately upon removal of the pipe section, the interior lumen was swabbed to remove the biofilm layer. Subsequent analysis for the presence of Helicobacter DNA using a nested PCR approach produced a positive result. This data provides the first evidence for the existence of Helicobacter in biofilms found in water distribution systems anywhere in the world.

Biofilms↗

Low prevalence of monoclonal B cells in Helicobacter pylori gastritis patients with duodenal ulcer.

We have studied the prevalence of B-cell clonality among a large group of 320 patients with Helicobacter pylori gastritis and duodenal ulcer. These patients underwent endoscopic examination with multiple gastric biopsies at diagnosis and were followed 2 and 12 months after therapy. Histopathologic examination of 809 sets of biopsy specimens showed lymphoid gastritis with lymphoid aggregates or follicles, but without lymphoepithelial lesion, in 302 samples corresponding to initial biopsy specimens (n=130) or to posttreatment biopsy specimens (n=172). DNA extracted from fresh antral specimens allowed the amplification of Helicobacter pylori DNA in all cases before therapy. The arrangement of the immunoglobulin heavy chain gene was studied by polymerase chain reaction (PCR) in the 302 selected lymphoid gastritis samples. Single or dominant bands were seen only in four specimens from three patients (1.3%), whereas a polyclonal pattern was seen in the other 298 samples. The detection threshold of our PCR technique was approximately 3% of clonal B cells diluted in a polyclonal population. This threshold appeared to be a reliable cutoff between polyclonal gastritis and clonal MALT lymphoma. In our experience, Helicobacter pylori lymphoid gastritis appeared mainly as a benign polyclonal condition.

Adult↗

Three treatment schemes with colloidal bismuth subcitrate (Q-ULCER) in peptic ulcer with Helicobacter pylori.

BACKGROUND: Since the discovery, several decades ago, of the infection of the gastric mucosa with Helicobacter pylori and its association with chronic antral gastritis and peptic ulcer, the treatment of ulcer illness has recently been revolutionized. METHODS: In this study, the clinical effectiveness of three schemes of treatment with colloidal bismuth subcitrate (CBS) were compared. Fifty-three patients suffering from gastroduodenal peptic ulcer with Helicobacter pylori were distributed randomly into three groups. Group I (n = 17) received 240 mg CBS every 12 h for 6 weeks. Group II (n = 17) received 240 mg CBS every 12 h for 6 weeks, pus metronidazole 500 mg every 8 h plus tetracycline 500 mg every 8 h for 10 days. Group III (n = 19) received 240 mg CBS every 12 h for 6 weeks, plus metronidazole 500 mg every 8 h plus amoxicillin 750 mg every 12 h for 10 days. A duodenoscopy investigation with antrum biopsy for a morphologic study and detection of the germ was carried out by means of urease test and histological study (Warthin-Sarry and hematoxylin-eosin). RESULTS: The three schemes of treatment were effective for ulcerous healing with 70.5%, 82.3%, and 78.2%, respectively, without significant differences. The highest clearing index (52.6%) was obtained in group III. CONCLUSIONS: With these treatments, the Helicobacter pylori eradication was only observed in 47.3% of the patients studied.

Amoxicillin↗

Helicobacter pylori and gastric cancer in Croatia.

The seroprevalence of Helicobacter pylori infection was studied in a population from two areas of Croatia with significantly different average gastric cancer (GC) cumulative incidence and mortality rates. In a random sample of 456 blood sera from both areas, which was tested with the ELISA Helicobacter pylori-antibody test, 48.8% of people in the north and 53.3% in the south of the country were found to be infected. The difference between the two areas in the seroprevalence of the infection was not statistically significant, nor did their populations differ in age, sex, educational background, smoking habit or wine consumption. Our results do not point to any association between the prevalence of Helicobacter pylori infection and the level of cumulative incidence and GC mortality levels.

Adult↗

Immunisation against gastric infection with Helicobacter species: first step in the prophylaxis of gastric cancer?

The discovery of the gastric bacterium, Helicobacter pylori and the demonstration of its role in the pathogenesis of gastroduodenal disease, has been one of the major microbiological advances in the last decade. Recent demonstration of long term infection with this bacterium as a risk factor in gastric carcinoma suggests that intervention in a disease of major morbidity and mortality is possible. Using a model of Helicobacter infection in mice it has been shown that oral immunisation with a sonicate of Helicobacter felis plus the adjuvant cholera toxin results in protection against an oral challenge with large numbers of viable bacteria. The success of the immunising regimen has been shown to correlate with the development of local immunity. Formulation of equivalent safe vaccines of H. pylori will make possible the immunisation of children in countries such as China, Japan and Columbia and so prevent the establishment of long term inflammation and thus significantly reduce the incidence of gastric cancer in those societies. This animal model is proposed as a major tool in the development of effective oral immunisation.

Animals↗

Synthesis and structure-activity relationships of 7-(2-aminoalkyl)morpholinoquinolones as anti-Helicobacter pylori agents.

A series of the titled compounds was synthesized and tested for anti-Helicobacter pylori activities. We discovered Y-34867 having the most potent activity against Helicobacter pylori among the quinolones tested along with high photostability. Furthermore, Y-34867 showed an excellent therapeutic effect in the experimental Helicobacter pylori infected Mongolian gerbil model.

4-Quinolones↗

Economic evaluation of empirical antisecretory therapy versus Helicobacter pylori test for management of dyspepsia: a randomized trial in primary care.

OBJECTIVES: An economic evaluation was performed of empirical antisecretory therapy versus test for Helicobacter pylori in the management of dyspepsia patients presenting in primary care. METHODS: A randomized trial in 106 general practices in the County of Funen, Denmark, was designed to include prospective collection of clinical outcome measures and resource utilization data. Dyspepsia patients (n = 722) presenting in general practice with more than 2 weeks of epigastric pain or discomfort were managed according to one of three initial management strategies: (i) empirical antisecretory therapy, (ii) testing for Helicobacter pylori, or (iii) empirical antisecretory therapy, followed by Helicobacter pylori testing if symptoms improved. Cost-effectiveness and incremental cost-effectiveness ratios of the strategies were determined. RESULTS: The mean proportion of days without dyspeptic symptoms during the 1-year follow-up was 0.59 in the group treated with empirical antisecretory therapy, 0.57 in the H. pylori test-and-eradicate group, and 0.53 in the combination group. After 1 year, 23 percent, 26 percent, and 22 percent, respectively, were symptom-free. Applying the proportion of days without dyspeptic symptoms, the cost-effectiveness for empirical treatment, H. pylori test and the combination were 12,131 Danish kroner (DKK), 9,576 DKK, and 7,301 DKK, respectively. The incremental cost-effectiveness going from the combination strategy to empirical antisecretory treatment or H. pylori test alone was 54,783 DKK and 39,700 DKK per additional proportion of days without dyspeptic symptoms. CONCLUSIONS: Empirical antisecretory therapy confers a small insignificant benefit but costs more than strategies based on test for H. pylori and is probably not a cost-effective strategy for the management of dyspepsia in primary care.

Adult↗

Identification of Helicobacter pylori DNA in Iranian patients with gallstones.

In order to identify Helicobacter in gallstones of Iranian patients with biliary disease, gallstone and bile samples from 33 patients were subjected to rapid urease test, culture and Multiplex PCR using primers based on 16s rRNA and isocitrate dehydrogenase genes for the identification of Helicobacter genus and H. pylori respectively. This PCR was also done on bile samples from 40 autopsied gallbladders with normal pathology (control group). In 18.1% of stone and 12.1% of bile samples, H. pylori DNA was detected using PCR. Rapid urease and culture tests were negative for all samples. The PCR was negative in the control group. In conclusion, H. pylori DNA was detected in stone samples of Iranian patients with gallstones but we are not sure of their viability. To clarify the clinical role of Helicobacter in gallbladder diseases, studies using accurate tests on larger patient and control groups are needed to ascertain whether this microorganism is an innocent bystander or active participant in gallstone formation.

Adult↗

Treatment of Helicobacter pylori infection in clinical practice in the United States: results from 224 patients.

Our objectives were to define treatment success, compliance, and side effects for treatment of Helicobacter pylori in clinical practice. In all, 224 consecutive patients received Helicobacter pylori treatment: 97 received two weeks of bismuth subsalicylate, metronidazole, tetracycline four times a day with a H2-receptor antagonist twice a day (BMT); 89 received one week of metronidazole, lansoprazole, and clarithromycin twice a day (MLC); and 38 received one week of BMT with lansoprazole twice a day (BMT-PPI). Cure rates were: BMT 81% (95% CI 74-89%), MLC 90% (95% CI 84-96%) BMT-PPI 87% (95% CI 81-92%). More patients prescribed a bismuth-based regimen discontinued medications due to side effects compared to MLC (P = 0.049). Nausea was more common for BMT compared to MLC (P = 0.04). In conclusion, treatment of Helicobacter pylori infection with a one-week course of MLC achieves a high rate of cure in clinical practice. Significantly fewer patients prescribed PPI-based therapy discontinue medications due to side effects as compared to bismuth-based triple therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Detection of Helicobacter-like bacteria in porcine gastric biopsy samples by amplification of 16S rRNA, ureB, vacA and cagA genes by PCR.

Preliminary evidence for the presence of Helicobacter-like bacteria was sought in 395 porcine gastric samples by a urease test. Of the samples, 37% (146/395) were urease-positive and 82% (82/100) of the Gram-stained urease-positive samples showed large, tightly spiralled organisms. Several methods were applied to culture the organisms but isolation was unsuccessful, contaminant organisms being considered to be one of the major problems. PCR with Helicobacter genus-specific primers for 16S rRNA and ureB genes, and primers for H. pylori vacA and cagA genes were tested with 102 ureasepositive biopsy samples. The PCR results showed some evidence for the presence of the urease and the vacA genes in porcine Helicobacter-like bacteria and raises the possibility of pathogenicity by these organisms.

Animals↗

Effect of rebamipide in treatment of Helicobacter pylori-associated duodenal ulcer: attenuation of chemokine expression and nitrosative damage.

Production of cytokines along with increased activity of nitric oxide synthase has been implicated as one of the contributing mechanisms of Helicobacter pylori-mediated gastroduodenal diseases. We aimed to evaluate the effect of rebamipide in treating Helicobacter pylori-associated duodenal ulcers in terms of cytokine production and nitrosative damage of the gastric mucosa. In patients with duodenal ulcers, rebamipide or placebo were given randomly after eradication. Mucosal cytokine production was measured by enzyme linked immunoassay, and nitrotyrosine immunoexpression was measured by immunohistochemistry. The inflammatory activity and degree of neutrophil infiltration were graded accordingly. The mucosal production of RANTES, interleukin-8, and TNF-alpha showed a significant decrease after eradication in patients with rebamipide after-treatment. The nitrotyrosine immunoreactivity of gastric epithelium was significantly decreased in the rebamipide group. Rebamipide treatment after eradication resulted in a significant reduction in chemokine production along with nitrotyrosine immunoexpression in Helicobacter pylori-associated duodenal ulcers.

Adult↗

Effect of potent urease inhibitor, fluorofamide, on Helicobacter sp. in vivo and in vitro.

The therapeutic potential of urease inhibition of Helicobacter pylori has been studied by examining the effect of the potent urease inhibitor, fluorofamide (N-(diaminophosphinyl)-4-fluorobenzenamide), on urease activity and bacterial survival in vivo and in vitro. In culture, acid protection in H. pylori was shown to be due to changes in the pH of the medium brought about by the release of ammonia. Both the acid protection and the ammonia release were completely blocked by fluorofamide at low doses (ED50 = approximately 100 nM). However, fluorofamide was unstable under acidic conditions (T1/2 = 5.7 min at pH 2). Despite this, fluorofamide was the best available compound to test in vivo. In ferrets naturally infected with H. mustelae, a single dose (50 mg/kg, per os) of fluorofamide completely inhibited bacterial urease. In repeat dosing studies, fluorofamide (50 mg/kg per os, three times a day) was compared with the Helicobacter triple therapy regime (amoxycillin, metronidazole, and bismuth subcitrate). Fluorofamide failed to eradicate the H. mustelae infection, compared to 80% eradication with triple therapy. However, histological samples showed a profound reduction in bacterial numbers following fluorofamide treatment. A combination of fluorofamide and amoxycillin was dosed to ferrets (seven days of treatment with 50 mg/kg fluorofamide plus 10 mg/kg amoxycillin per os twice a day); however, this failed to eradicate the infection, despite there being a reduction in bacterial numbers in 3/5 ferrets after 21 days after dosing stopped. It was concluded that urease inhibitors (either alone or in combination with antibiotics) are unlikely to have therapeutic potential for Helicobacter pylori infections. This is probably because, in vivo, some bacteria (perhaps dormant forms) are not entirely dependent upon urease for survival. However, given the acid instability of fluorofamide, the possibility that more stable urease inhibitors might have therapeutic potential, cannot be excluded.

Amoxicillin↗

Antibiotic properties of bovine lactoferrin on Helicobacter pylori.

To investigate a potential new treatment for gastric Helicobacter pylori infection, we have examined the use of the natural antibiotic lactoferrin, found in bovine milk, for activity against Helicobacter species both in vitro and in vivo. Lactoferrin was bacteriostatic to H. pylori when cultured at concentrations > or =0.5 mg/ml. Growth of H. pylori was not inhibited by another milk constituent, lysozyme, or by a metabolite of lactoferrin, lactoferricin B, but growth was inhibited by the iron chelator deferoxamine mesylate. Lactoferrin inhibition of growth could be reversed by addition of excess iron to the medium. Lactoferrin in retail dairy milk was found to be more stable intragastrically than unbuffered, purified lactoferrin. Treatment of H. felis-infected mice with lactoferrin partially reversed mucosal disease manifestations. It is concluded that bovine lactoferrin has significant antimicrobial activity against Helicobacter species in vitro and in vivo. Bovine lactoferrin should be further investigated for possible use in H. pylori infections in man.

Animals↗

Are Helicobacter species and enterotoxigenic Bacteroides fragilis involved in inflammatory bowel disease?

The aim of this study was to determine if either Helicobacter or enterotoxigenic Bacteroidesfragilis (ETBF) was linked to inflammatory bowel disease (IBD), using PCR. We analyzed the luminal washings and colonic biopsies of 35 patients with IBD and 37 control patients. The presence of Helicobacter was confirmed in the luminal washing of one IBD patient and three control patients and in the biopsies of two IBD patients. Ten of 28 control patients and 8 of 32 IBD patients had a positive luminal washing for the enterotoxin gene. Six of 33 control patients and 4 of 32 IBD patients had positive biopsies. The prevalence of the enterotoxin gene was higher in IBD patients with active disease compared with patients with inactive disease, although it did not achieve statistical significance. In conclusion, Helicobacter was not associated with IBD in our population of patients, although ETBF may be associated with active disease.

Adult↗

Review article: diagnosis and treatment of Helicobacter: a 2002 updated review.

The year 2002 saw advances on many fronts in the study of Helicobacter and gastroduodenal disease. Several studies have confirmed endoscopy as a valuable management procedure with confirmation of the diagnostic utility of the rapid urease test and the description of a new formulation of the test, which is more rapid in giving a result. Serology has been re-confirmed as a useful investigation in selected populations. Some commercial kits for near patient testing have also been assessed and although generally regarded as less accurate than laboratory based tests some have shown acceptable accuracy. The recent exciting development in diagnostic serology is the availability of the faecal antigen test; further studies have confirmed its usefulness as recommended screening tests. There have been several studies demonstrating that a test and treat policy has a significant patient benefit, both economic and medical, although there is some doubt if eradication of Helicobacter leads to regression of atrophy and metaplasia. However, in low Helicobacter-prevalence areas the test and treat policy is being challenged as an effective management strategy. Further studies have shown that compliance with treatment regimens is an important determinant of successful eradication. Finally several new eradication regimens have been reported particularly for use in patients who have had previous unsuccessful eradication attempts.

Biopsy↗