Prevalence of peptic ulcer in Helicobacter pylori positive blood donors

Expression of tryptophan hydroxylase in gastric mucosa in symptomatic and asymptomatic Helicobacter pylori infection

INTRODUCTION

Helicobacter pylori infection induces clinical symptoms in 15-20% of subjects, and the reason for this variation is still not clear. The aim of the present study is to evaluate the expression of tryptophan hydroxylase (TpH-1) in gastric mucosa of patients with symptomatic and asymptomatic H. pylori infection in relation to the intensity of bacterial colonization and severity of dyspeptic symptoms.

MATERIAL AND METHODS

Ninety subjects (aged 35-49 years) were enrolled in the study and separated into 3 groups of 30 subjects each. Group I - healthy volunteers without H. pylori infection, group II - subjects with asymptomatic H. pylori infection, group III - H. pylori-infected patients with dyspeptic symptoms, mainly fasting and nocturnal epigastric pain. To diagnose H. pylori infection the urea breath test (UBT-13C) and histological analysis were performed. The level of mRNA expression of tryptophan hydroxylase (TpH-1) was estimated in gastric mucosa with RT-PCR.

RESULTS

The expression of this enzyme in antral mucosa was 2.69 ±0.97 in group I, 2.28 ±0.69 in group II (p > 0.05) and 4.40 ±1.64 in group III (p < 0.001). The levels of expression of TpH-1 in gastric body mucosa were 2.16 ±0.70, 1.57 ±0.52 (p > 0.05) and 3.40 ±1.51 (p < 0.001), respectively. In group III a positive correlation was found between intensity of H. pylori colonization and TpH-1 expression as well as between TpH-1 expression and severity of dyspeptic symptoms.

CONCLUSIONS

Increased expression of TpH-1 in gastric mucosa plays a role in pathogenesis of chronic dyspepsia.

Identification of distinctive clinical significance in hospitalized patients with endoscopic duodenal mucosal lesions

BACKGROUND/AIMS

Duodenitis is not infrequent finding in patient undergoing endoscopy. However, hospitalized patients have a higher incidence of secondary duodenal mucosal lesions that might be related with inflammatory bowel disease (IBD), cytomegalovirus (CMV) infection, tuberculosis, immunologic disorders, or other rare infections. We aimed to identify clinicopathologic features of duodenal mucosal lesions in hospitalized patients.

METHODS

All hospitalized patients having duodenal mucosal lesions were identified by endoscopic registration data and pathologic data query from 2011 to 2014. The diagnostic index was designed to be sensitive; however, a detailed review of medical record and endoscopic findings was undertaken to improve specificity. Secondary duodenal lesion was defined as having specific reason to explain the duodenal lesion.

RESULTS

Among 6,334 hospitalized patients have undergone upper endoscopy, endoscopic duodenal mucosal lesions was detected in 475 patients. Secondary duodenal lesions was 21 patients (4.4%) and the most frequent secondary cause was IBD (n = 7). The mean age of secondary group was significantly lower than that in primary group (42.3 ± 18.9 years vs. 58.5 ± 16.8 years, p = 0.00), and nonsteroidal anti-inflammatory drugs were less frequently used in secondary group, but there was no differences of gender or presence of Helicobacter pylori. The involvement of distal part of duodenum including postbulbitis or panduodenitis was more frequently detected in secondary group than in primary group. By multivariate regression analysis, younger age of 29 years and the disease extent were significant predictors for the secondary mucosal lesions.

CONCLUSIONS

Secondary duodenal mucosal lesions with different pathophysiology, such as IBD or CMV infection, are rare. Disease extent and age seems the most distinctive feature of secondary duodenal mucosal lesions.

Helicobacter pylori: Effect of coexisting diseases and update on treatment regimens

The presence of concomitant diseases is an independent predictive factor for non-Helicobacter pylori (H. pylori) peptic ulcers. Patients contracting concomitant diseases have an increased risk of developing ulcer disease through pathogenic mechanisms distinct from those of H. pylori infections. Factors other than H. pylori seem critical in peptic ulcer recurrence in end stage renal disease (ESRD) and cirrhotic patients. However, early H. pylori eradication is associated with a reduced risk of recurrent complicated peptic ulcers in patients with ESRD and liver cirrhosis. Resistances to triple therapy are currently detected using culture-based and molecular methods. Culture susceptibility testing before first- or second-line therapy is unadvisable. Using highly effective empiric first-line and rescue regimens can yield acceptable results. Sequential therapy has been included in a recent consensus report as a valid first-line option for eradicating H. pylori in geographic regions with high clarithromycin resistance. Two novel eradication regimens, namely concomitant and hybrid therapy, have proven more effective in patients with dual- (clarithromycin- and metronidazole-) resistant H. pylori strains. We aim to review the prevalence of and eradication therapy for H. pylori infection in patients with ESRD and cirrhosis. Moreover, we summarized the updated H. pylori eradication regimens.

The stomach in health and disease

The stomach is traditionally regarded as a hollow muscular sac that initiates the second phase of digestion. Yet this simple view ignores the fact that it is the most sophisticated endocrine organ with unique physiology, biochemistry, immunology and microbiology. All ingested materials, including our nutrition, have to negotiate this organ first, and as such, the stomach is arguably the most important segment within the GI tract. The unique biological function of gastric acid secretion not only initiates the digestive process but also acts as a first line of defence against food-borne microbes. Normal gastric physiology and morphology may be disrupted by Helicobacter pylori infection, the most common chronic bacterial infection in the world and the aetiological agent for most peptic ulcers and gastric cancer. In this state-of-the-art review, the most relevant new aspects of the stomach in health and disease are addressed. Topics include gastric physiology and the role of gastric dysmotility in dyspepsia and gastroparesis; the stomach in appetite control and obesity; there is an update on the immunology of the stomach and the emerging field of the gastric microbiome. H. pylori-induced gastritis and its associated diseases including peptic ulcers and gastric cancer are addressed together with advances in diagnosis. The conclusions provide a future approach to gastric diseases underpinned by the concept that a healthy stomach is the gateway to a healthy and balanced host. This philosophy should reinforce any public health efforts designed to eradicate major gastric diseases, including stomach cancer.

Hybrid vs sequential therapy for eradication of Helicobacter pylori in Taiwan: A prospective randomized trial

AIM: To evaluate the efficacy of sequential vs hybrid therapy in patients with Helicobacter pylori (H. pylori) infection.

METHODS: From March 2013 to May 2014, one hundred and seventy-five H. pylori infected patients who had not been treated for H. pylori before were randomized to receive either sequential therapy (rabeprazole 20 mg and amoxicillin 1 g twice daily for 5 d, followed by rabeprazole 20 mg, clarithromycin 500 mg and metronidazole 500 mg twice daily for 5 d) or hybrid therapy (rabeprazole 20 mg and amoxicillin 1 g for 7 d, followed by rabeprazole 20 mg, amoxicillin 1 g, clarithromycin 500 mg and metronidazole 500 mg twice daily for 7 d). H. pylori status was confirmed by positive results of both rapid urease test and histology examination or a positive result of culture. Eradication efficacy was assessed by follow-up endoscopy with rapid urease test and histological examination 8 wk after the end of anti-H. pylori therapy, or ¹³C-urea breath test at least 4 wk after completion of treatment. The primary outcome was H. pylori eradication by intension-to-treat (ITT) and per-protocol (PP) analyses.

RESULTS: One hundred and sixty-seven patients (83 patients in the sequential group and 84 patients in the hybrid group) completed the study. The compliance rates were 97.6% and 97.7% for the two groups, respectively. The eradication rate was 78.2% for the sequential group and 92% for the hybrid group by ITT analysis (P = 0.01). The eradication rate was 81.9% for the sequential group and 96.4% for the hybrid group by PP analysis (P = 0.01). Univariate analysis for the clinical and bacterial factors did not identify any risk factors associated with treatment failure. Severe adverse events were observed in 2.3% of patients in the sequential group and 2.4% of those in the hybrid group.

CONCLUSION: Due to a grade A (> 95%) success rate for H. pylori eradication by PP analysis, similar compliance and adverse events, hybrid therapy seems to be an appropriate eradication regimen in Taiwan.

Performance of Routine Helicobacter pylori Invasive Tests in Patients with Dyspepsia

Background. This study was designed to compare the accuracy of three different invasive methods for the detection of Helicobacter pylori (H. pylori) infection in patients with dyspepsia. These tests included culture, histology, and the rapid urease test (CLO test). Methods. H. pylori infection was diagnosed prospectively in 246 untreated dyspeptic patients who underwent upper gastrointestinal endoscopy. The gold standard for H. pylori infection was based on a positive culture or both a positive histological examination and a CLO test. Results. H. pylori was diagnosed in 33.3% of the patients. The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were as follows: histology from the antrum (95.12; 95.12; 90.7; 97.5; 95.12%); histology from the antrum and corpus (95.12; 95.12; 90.7; 97.5; 95.12%); histology from the corpus (76.83; 96.95; 92.65; 89.33; 90.24%); culture (91.46; 100; 100; 95.91; 97.15%); a CLO test from the antrum and corpus (85.59; 100; 100; 93.71; 95.52%); a CLO test from the antrum (64.63; 100; 100; 84.97; 88.21%); a CLO test from the corpus (69.51; 100; 100; 96.77; 89.83%), respectively. Conclusions. Antral biopsy histology and culture are the best methods for the diagnosis of H. pylori infection in our cohort of patients with dyspepsia.

Dual specimens increase the diagnostic accuracy and reduce the reaction duration of rapid urease test

AIM: To evaluate the influence of multiple samplings during esophagogastroduodenoscopy (EGD) on the accuracy of the rapid urease test, and the validity of newly developed rapid urease tests, HelicotecUT plus test and HelicotecUT test, CLO test and ProntoDry test.

METHODS: A total of 355 patients undergoing EGD for dyspepsia were included. Their Helicobacter pylori (H. pylori) treatment status was either naïve or eradicated. Six biopsy specimens from antrum and gastric body, respectively, were obtained during EGD. Single antral specimens and dual (antrum + body) specimens were compared. Infection status of H. pylori was evaluated by three different tests: culture, histology, and four different commercially available rapid urease tests (RUTs)-including the newly developed HelicotecUT plus test and HelicotecUT test, and established CLO test and ProntoDry test. H. pylori status was defined as positive when the culture was positive or if there were concordant positive results among histology, CLO test and ProntoDry test.

RESULTS: When dual specimens were applied, sensitivity was enhanced and RUT reaction time was significantly reduced, regardless of their treatment status. Thirty minutes were enough to achieve an agreeable positive rate in all the RUTs. Both newly developed RUTs showed comparable sensitivity, specificity and accuracy to the established RUTs, regardless of patient treatment status, RUT reaction duration, and EGD biopsy sites.

CONCLUSION: Combination of antrum and body biopsy specimens greatly enhances the sensitivity of rapid urease test and reduces the reaction duration to 30 min.

Seroprevalence of Helicobacter pylori among Tunisian blood donors (outpatients), symptomatic patients and control subjects

OBJECTIVES

Helicobacter pylori is a worldwide infection, although little data are available in the Tunisian population. The aims of our study were to detect the prevalence of H. pylori in a blood-donor population (n=250) and in another population of hospital-consulting patients comprising 87 symptomatic patients and 59 controls, and to determine the factors that influence the prevalence.

MATERIALS AND METHODS

Study subjects answered a standardized questionnaire, and IgG anti-H. pylori and anti-cag were detected by ELISA. In the second population, culture and cagA polymerase chain reaction were performed.

RESULTS

The seroprevalence of H. pylori in blood donors was 64%, and 11% had anti-cag. All patients positive for anti-cag were also positive for anti-H. pylori antibodies. The seroprevalence of H. pylori was 99.3% in the hospital-consulting patients, of whom 55.5% were positive for anti-cag. The difference between the anti-cag and symptomatic patients (66.7%) and controls (39%) was significant. Symptomatic patients had a higher rate of anti-cag (66.7%) compared with the controls (39%) and blood donors (11%).

CONCLUSION

H. pylori seroprevalence in blood donors is low (64%) compared with symptomatic patients (99.3%), and anti-cag was statistically associated with symptomatic patients and pathology. Also, some environmental factors were correlated with H. pylori seroprevalence.

Helicobacter pylori infection and Barrett's esophagus: a systematic review and meta-analysis

OBJECTIVES

The majority of distal esophageal adenocarcinomas are believed to arise in patients with Barrett's esophagus (BE). Helicobacter pylori (H. pylori) infection plays an etiological role in gastric carcinogenesis, but any possible role in BE is uncertain. We aimed to explore the possible relationship between H. pylori infection and BE by meta-analysis.

METHODS

Observational studies comparing the prevalence of H. pylori infection in patients with BE and healthy controls conducted in adult populations and published in all languages were identified through MEDLINE, EMBASE, and Cochrane database searches up to week 5, 2008. H. pylori infection had to be confirmed by histology and/or serology and/or RUT and/or culture. Studies were excluded if no raw data for outcomes of interest were available or controls were patients with disease or duplicate publications. Summary effect size was calculated as odds ratio (OR) and 95% confidence intervals (CIs) by the random-effects model using Review Manager 4.2.8.

RESULTS

Of 519 citations identified, a total of 12 case-control studies compared the prevalence of H. pylori infection in BE (n=550) and controls (9 studies included controls with normal endoscopy and 3 studies used healthy blood donors as control, n=2,979). There was no significant difference in the overall prevalence of H. pylori infection between BE and controls (42.9% vs. 43.9%, OR=0.74, 95% CI 0.40-1.37, P=0.34), but with significant heterogeneity. Subgroup analysis showed that the prevalence of H. pylori infection was significantly lower in BE than in endoscopically normal healthy controls (23.1% vs. 42.7%, OR=0.50, 95% CI 0.27-0.93, P=0.03) with significant heterogeneity observed between studies. The heterogeneity was eliminated by excluding a single Asian outlier study. In contrast, H. pylori infection was significantly increased in BE patients in the three studies using healthy blood donors as "normal controls" (71.2% vs. 48.1%, OR=2.21, 95% CI 1.07-4.55). In BE patients, the prevalence of H. pylori infection was significantly lower in the esophagus than in the stomach (3.3% vs. 24.7%, OR=0.14, 0.03-0.67) in three studies.

CONCLUSIONS

H. pylori infection and BE are inversely related when compared with endoscopically normal controls but not blood donor controls. Limited evidence suggests that there is no clear association between H. pylori infection and BE. To determine more accurately the effect size of H. pylori infection in BE, high quality prospective case-control studies with age-matched, endoscopically normal healthy controls are needed.

Antimicrobial susceptibility of Helicobacter pylori strains in a random adult Swedish population

BACKGROUND AND AIM

Antimicrobial resistance in Helicobacter pylori is a growing problem and has become an important factor leading to eradication failure. Information on antimicrobial susceptibility is important for selection of an optimum treatment regimen. The resistance rate in a random population has not been studied previously.

METHODS

A random Swedish population sample (n = 3000, age 20-1 years) was surveyed using a mailed validated questionnaire assessing gastrointestinal symptoms (response rate of 74%). One-third of the responders was invited, in random order, and accepted an esophagogastroduodenoscopy with biopsies for H. pylori culture and histology. Subjects were not treated for their H. pylori infection but a minimum inhibitory concentration of metronidazole, clarithromycin, amoxicillin, and tetracycline for the H. pylori isolates (n = 333) was determined by agar dilution. Prescribed antibiotic in the area was recorded.

RESULTS

Irrespective of symptomatology, 16.2% of the isolated H. pylori strains were resistant to metronidazole, 1.5% to clarithromycin, 0% to amoxicillin, and 0.3% to tetracycline. The antibiotic consumption was low from an international perspective.

CONCLUSION

The resistance to the antibiotics was lower than expected from patient sample studies, especially for clarithromycin, most probably due to a restrictive prescription policy in the area. Introduction of a test-and-treat strategy in Sweden would only marginally affect the usage of clarithromycin.

Rifaximin-based regimens for eradication of Helicobacter pylori: a pilot study

BACKGROUND

Triple therapy is the treatment of choice for Helicobacter pylori-infected patients with an eradication rate ranging from 70 to 85%. Poor compliance and antibiotic resistance are the main causes of treatment failure. The aim of the present study was to assess the efficacy of rifaximin, a poorly absorbed antibiotic, for H. pylori eradication.

METHODS

We enrolled 48 consecutive H. pylori-positive patients affected. They were randomized to receive two 7-day rifaximin-based triple therapies: rifaximin tablets 400 mg t.i.d., esomeprazole 40 mg o.d. and clarithromycin 500 mg b.i.d. (CRE) or levofloxacin 500 mg o.d. (LRE). H. pylori eradication was assessed using a (13)C-urea breath test 4 weeks after the end of therapy. Treatment compliance and the incidence of side effects were also evaluated.

RESULTS

No dropouts were observed. The eradication rate both on intention-to-treat and per-protocol analysis did not show significant differences between groups: 58% (14/24 patients) in group 1 and 42% (10/24 patients) in group 2 (p = 0.24, OR 1.96, 95% CI 0.62-6.18). No significant differences in patients' compliance and incidence of side effects were found between groups.

CONCLUSIONS

Rifaximin-based therapy showed optimal compliance but a limited eradication rate compared to standard first-line treatment. Further investigations are needed to evaluate different dosages and combinations.

Evaluation of urine ELISA test for detecting Helicobacter pylori infection in Taiwan: A prospective study

AIM: To evaluate the diagnostic accuracy and clinical utility of a new ELISA (URINELISA) test for detecting Helicobacter pylori (H pylori) antibody in the urine of Taiwanese population.

METHODS: In this prospective study, 317 consecutive dyspeptic patients (171 men, 146 women; mean age, 51.0 years) were included. They underwent gastroendoscopy for evaluation. Invasive tests, including culture, histology, and rapid urease test (RUT), and non-invasive 13C-urea breath test were preformed. At the same time, urine specimens were collected for URINELISA. The status of H pylori infection was considered as positive when either culture was positive, or when two of the other, RUT, histology or 13C-UBT, were positive.

RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of URINELISA are 91.7% (211/230), 90.8% (79/87), 96.3% (211/219), and 80.6% (79/98) respectively.

CONCLUSION: This URINELISA test is reliable, inexpensive and easy-to-use. The high diagnostic accuracy warrants the use of URINELISA as a first-line screening tool for diagnosis of H pylori infection in untreated patients.

Review article: oesophageal complications and consequences of persistent gastro-oesophageal reflux disease

The major oesophageal complications associated with persistent gastro-oesophageal reflux disease (GERD) include erosive oesophagitis, ulceration, strictures and gastrointestinal (GI) bleeding. Although the causes of these complications are uncertain, studies indicate that erosive oesophagitis may progress to the development of ulcers, strictures and GI bleeding. Pharmacological treatment with proton pump inhibitors is favoured over that with H(2)-receptor antagonists for the treatment of strictures. The treatment of strictures is accomplished with dilation and many favour the concomitant use of proton pump inhibitors. Most gastroenterologists are seeing far fewer oesophageal strictures these days since the introduction of proton pump inhibitors. In addition, research has shown that oesophageal complications have a greater impact on patients suffering from night-time GERD than on those suffering from daytime GERD. Barrett's oesophagus is a significant complication associated with persistent GERD and those at risk generally experience a longer duration of symptoms, especially those with a high degree of severity. In addition, there is a strong relationship between Barrett's oesophagus and oesophageal adenocarcinoma. This is in part due to the association of obesity and the development of hiatal hernias. Furthermore, endoscopic screening is being used to detect Barrett's oesophagus and oesophageal adenocarcinoma in persons suffering from chronic GERD, even though screening may not have an impact on outcomes (Sharma P, McQuaid K, Dent J, et al. A critical review of the diagnosis and management of Barrett's esophagus: The AGA Chicago Workshop. Gastroenterology 2004; 127: 310-30.).

Symptom patterns in functional dyspepsia and irritable bowel syndrome: relationship to disturbances in gastric emptying and response to a nutrient challenge in consulters and non-consulters

BACKGROUND

Our aim was to assess the relationship between gastric motor and sensory function and symptom patterns in community subjects and patients with functional dyspepsia (FD) or irritable bowel syndrome (IBS).

METHODS

We recruited 291 asymptomatic blood donors, 151 symptomatic blood donors (recurrent abdominal pain or discomfort), and 40 patients with FD or IBS. Abdominal symptoms were assessed using the bowel disease questionnaire (BDQ) and, in addition, the most bothersome symptom complex identified (dysmotility-type, ulcer-type dyspepsia, or IBS). Gastric emptying time (GET (t(1/2), min)) was measured by (13)C-octanoic breath test and a nutrient challenge performed. Twenty randomly selected asymptomatic blood donors, 48 symptomatic blood donors (30 FD, 18 IBS), and 40 patients (23 FD, 17 IBS) had additional function testing.

RESULTS

GET (t(1/2)) was significantly (p<0.05) longer in blood donors with FD symptoms (99 (6) min) and FD patients (110 (12) min) compared with asymptomatic controls (76.7 (7) min), but was not significant in IBS blood donors or patients. Overall, 25 of 48 blood donors with symptoms and 18 of 40 patients had slow gastric emptying. GET was most delayed in subjects with predominantly dysmotility-type symptoms (167 (36) min v controls; p<0.01). Symptom intensities after a nutrient challenge were significantly higher in FD patients and symptomatic blood donors compared with asymptomatic controls; 14 of 48 blood donors with symptoms and 16 of 40 patients had a symptom response to the nutrient challenge exceeding the response (mean (2SD)) of healthy asymptomatic controls.

CONCLUSION

Gastric emptying and the global symptom response to a standardised nutrient challenge are abnormal in population based (non-health care seeking) subjects with dyspepsia.

Relationship between Helicobacter pylori infection and the prevalence, site and histological type of gastric cancer

AIM

To evaluate the relationship between Helicobacter pylori infection and gastric cancer in Japan.

METHODS

This was a multicentre study conducted in various regions in Japan. A total of 6578 individuals as controls and 2503 with histologically confirmed gastric cancer were enrolled. H. pylori status was determined by enzyme-linked immunosorbent assay (ELISA) for anti-H. pylori immunoglobulin G (IgG).

RESULTS

The prevalence of H. pylori infection in gastric cancer patients was markedly high in all age groups. In contrast, the rate increased with age among control subjects. The overall prevalence of H. pylori infection in control subjects was 50.2% (3300/6578) vs. 82.8% in gastric cancer patients (2072/2503) (OR = 2.47; 95% CI: 2.19-2.79). The prevalence of H. pylori in early gastric cancer was significantly higher than that in advanced gastric cancer (86.5% vs. 75.7%; OR = 2.06; 95% CI: 1.66-2.55). There were no significant differences in the prevalence of H. pylori between the intestinal and diffuse types of gastric cancer or among gastric cancer in antrum, body and cardia.

CONCLUSION

H. pylori infection is strongly associated with the development of gastric cancer. The difference in odds ratios among younger and older persons with gastric cancer likely reflects the decrease in prevalence of H. pylori in the population, and is more reflective of the actual risks associated with the infection.

Is esophagoscopy alone sufficient for patients with reflux symptoms?

BACKGROUND

Unsedated esophagoscopy with ultrathin endoscopes is a valuable screening modality for Barrett's esophagus, but the stomach and the duodenum cannot be examined completely with the smallest and best tolerated of these endoscopes. There are no data as to how often disease in the stomach and the duodenum would be missed when using this screening strategy. Our hypothesis is that patients with reflux symptoms, in the absence of daily abdominal pain, nausea, or history of ulcer, were unlikely to have clinically significant gastroduodenal disease.

METHODS

Patients scheduled for upper endoscopy at a single outpatient endoscopy unit in a tertiary referral center were screened. The inclusion criterion was reflux symptoms as the primary indication for upper endoscopy. Patients with another valid indication were excluded. A detailed history was recorded and symptom questionnaire completed for each patient before endoscopy; these data were compared with the endoscopy findings.

RESULTS

A total of 175 patients were included. Indications for upper endoscopy were the following: worsening symptoms (n=74), ongoing reflux despite therapy (n=27), and long-standing reflux (n=74). Major esophageal findings were discovered in 95 patients. In 10 patients, major gastric or duodenal findings were detected as follows: erosive gastritis (n=8), gastric ulcer (n=2), duodenal ulcer (n=2), erosive duodenitis (n=2), and duodenal polyp (n=1). Daily abdominal pain (p=0.014) or possibly daily nausea (p=0.028 unadjusted, 0.197 adjusted) was associated with major gastric/duodenal disease. Patients without daily abdominal pain, nausea, or a history of gastric/duodenal ulcer were much less likely to have major disease (0.9%) than patients with one of these predictors (13.2%, p=0.00097).

CONCLUSIONS

Daily abdominal pain and nausea, in combination with a history of ulcer disease, are strong predictors of major gastric or duodenal disease. Patients with reflux without these predictors are highly unlikely to have a major disease involving the stomach or duodenum, and are suitable candidates for esophagoscopy alone.

Metronidazole-resistant Helicobacter pylori is more prevalent in patients with nonulcer dyspepsia than in peptic ulcer patients in a multiethnic Asian population

The trend of increasing prevalence of antibiotic resistance among Helicobacter pylori strains has been suggested as a cause of the failure of treatment of H. pylori infections. In this study, 120 of 211 antral biopsy specimens from patients with dyspeptic symptoms were found to harbor H. pylori. The isolates from the 120 specimens were tested by the agar dilution method, and 38 (31.7%) were found to be metronidazole resistant. Among the 211 subjects, 81 of 115 (70.4%) patients with peptic ulcer (PU) were infected with H. pylori, whereas 39 of 96 (40.6%) patients with nonulcer dyspepsia (NUD) were infected with H. pylori. Interestingly, significantly more NUD patients than PU patients harbored metronidazole-resistant H. pylori (22 of 39 [56.4%] and 16 of 81 [19.8%], respectively; P < 0.001). A similar pattern was also observed among NUD patients of different ethnicities but not between male and female patients (23 of 78 [29.5%] and 15 of 42 [35.7%], respectively; P = 0.54). In the posttreatment follow-up, five of six patients who had positive urea breath test results, indicating treatment failure, were NUD patients. Of these, four harbored metronidazole-resistant H. pylori strains. This further illustrates the relevance of metronidazole-resistant H. pylori in NUD patients. The significantly higher percentage of metronidazole-resistant H. pylori isolates in NUD patients may be attributed to the protection offered by the mucus layer of the nonulcerated stomach to the bacteria that reside below it, resulting in organism exposure to sublethal concentrations of metronidazole and leading to the induction of metronidazole resistance. The results demonstrate that the H. pylori isolates colonizing NUD patients are more likely to be resistant to metronidazole. It will therefore be useful to reevaluate the use of metronidazole in the treatment of NUD patients infected with H. pylori.

Effect of Helicobacter pylori eradication on development of dyspeptic and reflux disease in healthy asymptomatic subjects

BACKGROUND AND AIM

There are few data on the course of Helicobacter pylori infection in asymptomatic subjects. The aim of this study was to assess the effect of eradication therapy on the development of dyspeptic and gastro-oesophageal reflux disease in a cohort of asymptomatic individuals observed over a prolonged period.

METHODS

A total of 169 blood donors infected with H pylori who had volunteered for studies on eradication in 1990 formed the cohort. To be included in this cohort subjects had to have no symptoms, as determined by a validated symptom questionnaire at the baseline visit. Eighty eight subjects were infected with H pylori while 81 had successfully undergone eradication therapy. Subjects were followed up (annually) using the same symptom questionnaire and in 2000 they underwent repeat endoscopy.

RESULTS

Thirteen subjects developed symptoms during follow up. The incidence of symptoms in H pylori positive subjects was 1.893/100 person-years of follow up and in H pylori negative individuals 0.163/100 person-years of follow up. H pylori infected subjects were significantly more likely to develop symptoms (log rank test, p=0.003) as well as those infected with CagA positive strains (log rank test, p=0.017). The development of symptomatic gastro-oesophageal reflux disease was no different in individuals with and without eradication (odds ratio 0.57 (95% confidence interval 0.26-1.24); p=0.163).

CONCLUSIONS

H pylori eradication prevents the development of dyspeptic symptoms and peptic ulcer disease in healthy asymptomatic blood donors and is not associated with an increase in the incidence of symptomatic gastro-oesophageal reflux disease.

Prevalence of Helicobacter pylori infection in Warao lineage communities of Delta Amacuro State, Venezuela

The purpose of this study was the evaluation of Helicobacter pylori infections in children and adults from two indigenous communities of Delta Amacuro State, Venezuela, that differ in hygienic conditions of the housing. The evaluation was performed in 98 children (mean age 7 +/- 3.37 years) and their mothers (33.96 +/- 13.77 years) from two communities of Warao lineage. Anti-H. pylori serum IgG and secretory anti-H. pylori IgA antibodies were determined, as well as total secretory IgA and H. pylori antigens in feces. Serological prevalence of H. pylori infection was 38% in children and 84% their in mothers. Children from the community that had the most deficient sanitary and hygienic conditions had significantly lower titers of specific IgG antibodies and total secretory IgA (P<0.0001) and a high percentage of them had H. pylori antigens in their feces (P<0.0001). The levels of specific IgA were similar in both groups. The results indicate that in these populations there is a high prevalence of H. pylori infection and that poor hygienic conditions can increase the risk of infection and damage to the gastrointestinal tract.

Unexpected decrease with age of Helicobacter pylori seroprevalence among Swedish blood donors

Blood donors are often used as proxies for the general population in studies of Helicobacter pylori epidemiology. Our aim was to test if the age-specific seroprevalence rates among blood donors match with the corresponding rates in a random population sample. This descriptive study was based on sera obtained from 3,502 blood donors representing all Swedish counties and cities. An age-stratified random population sample of 1,030 from Stockholm County served as comparison. Sera were analyzed by an in-house enzyme-linked immunosorbent assay for H. pylori immunoglobulin G antibodies. In the population sample, we found the expected increase with age in the seroprevalence of H. pylori infection. This was true also among young blood donors, while the prevalence-by-age curve showed a deflection downward among blood donors who are >/= 50 years of age. In this age group, the probability of being seropositive was reduced by 73% (95% confidence interval [CI], 63 to 81%) relative to the population sample. Overall, the adjusted odds ratio for H. pylori seropositivity among blood donors was decreased by 43% (95% CI, 28 to 55%). Thus, it appears that blood donors who are H. pylori seropositive selectively disappear from the blood donor cohort. We speculate that H. pylori-seropositive blood donors may tolerate repeated bleedings less well than do noninfected individuals and/or that the general well-being among those who are infected may be somewhat impaired. Our unexpected observation indicates that blood donors may be less suitable as proxies for the general population in analytic studies of H. pylori infection and that the underlying cause needs further study.

Diagnostic methods for Helicobacter pylori detection and eradication

Helicobacter pylori is the principal cause of peptic ulcer disease and an important risk factor for the development of gastric cancer. The efficacy of 1 week triple therapies, which often have eradication rates of>90%, is undermined by poor patient compliance and bacterial antimicrobial resistance. The development of new anti-H. pylori therapies presents enormous challenges to clinical pharmacologists, not only in the identification of novel targets, but also in ensuring adequate drug delivery to the unique gastric mucus niche of H. pylori. Animal models of H. pylori infection have been developed but their clinical validity has yet to be established. Vaccination, to prevent or treat infection, has been demonstrated in animal models, but human studies have not been so encouraging.

Serodiagnosis of Helicobacter pylori infection is not accurate for children aged below 10

BACKGROUND

In order to investigate the immune response to Helicobacter pylori in childhood, we compared anti-H. pylori IgG and IgA antibodies with H. pylori antigen in the stool and examined the clinical usefulness of the anti-H. pylori IgG and IgA antibodies.

METHODS

This study included 157 children who were seen at our hospital. Serum and stool samples were obtained for these children. Antibodies to H. pylori were examined using an H. pylori IgG enzyme-linked immunosorbent assays (ELISA) and an H. pylori IgA ELISA. Analysis of stool samples was carried out by the H. pylori stool antigen (HpSA) enzyme immunoassay.

RESULTS

Of the 157 children, 45 children were HpSA positive, 110 were negative and two were undetermined. Out of 45 HpSA positive patients, 25 children were both IgG and IgA positive and seven were negative for both IgG and IgA antibodies. Of the 110 patients who were HpSA negative, 97 were negative for both antibodies. All HpSA positive children older than 10 years were positive for IgG and IgA antibodies, but of the HpSA positive children under the age of 10, only 18 out of 35 (51.4%) were positive for IgG antibodies or IgA antibody.

CONCLUSION

These facts suggested that an immature immune response or tolerance to H. pylori exists in childhood and serodiagnosis of H. pylori infection is less useful in children aged below 10.

Epidemiology of Helicobacter pylori and peptic ulcer in India

BACKGROUND

There is a wide variation in the prevalence of peptic ulcer in India both before and since the use of endoscopy. We studied the prevalence of peptic ulcer disease in a community in northern India and its relationship with Helicobacter pylori infection.

METHODS

A house-to-house survey of residents aged 15 years or above in a sub-sector of Chandigarh was performed as part of a pilot survey. Subsequently, the study randomly covered all sectors of Chandigarh and we screened 2649 persons. A questionnaire was administered to each subject by trained staff. All individuals with history of peptic ulcer/dyspepsia and an equal number of asymptomatic individuals were asked to attend the outpatient department of the Institute. Diagnosis of peptic ulcer was based on endoscopy or history of previous ulcer surgery.

RESULTS

Two hundred and fifty-four individuals attended the outpatient department at the Institute and 147 underwent endoscopy, biopsy for histology and rapid urease test, and blood was collected for H. pylori serology. There were 80 symptomatic and 67 asymptomatic individuals. Helicobacter pylori was positive in 38 (56.7%) asymptomatic and 49 (61.3%) symptomatic individuals (P > 0.05). The point prevalence of active peptic ulcer was 3.4% and the lifetime prevalence was 8.8%. The duodenal-to-gastric ulcer ratio was 12:1. Helicobacter pylori was present in 11/13 (84.6%) subjects with peptic ulcer. Peptic ulcer was more common in elderly and dyspeptic individuals and there was no effect of sex or socioeconomic status. Helicobacter pylori was associated with age only and did not depend on sex, socioeconomic status or dyspepsia. Of the 38 asymptomatic persons having H. pylori infection, none had active peptic ulcer.

CONCLUSIONS

This study demonstrates frequent occurrence of peptic ulcer and H. pylori in this part of the country. Peptic ulcer was more prevalent in the elderly and dyspeptic subjects. Helicobacter pylori was not associated with dyspepsia, and was more prevalent in elderly subjects. There was a low prevalence of peptic ulcer in asymptomatic H. pylori-infected persons in this community.

[Epidemiological aspects of Helicobacter pylori infection in childhood and adolescence]

The scope of the review is to study the epidemiological aspects of Helicobacter pylori infection and its importance during childhood and adolescence, focusing on incidence, prevalence, transmission and risk factors. The study's references included the following databases: LILACS (PAHO/ Bireme), MEDLINE, the US's National Library of Medicine and the thesis developed at University of São Paulo for the period 1983 to 1999. It was noted that Helicobacter pylori infection is mainly acquired during childhood, age-related prevalence, main risk factors are associated to low socioeconomic status, and its transmission mechanism remains unclear.

H. pylori and functional dyspepsia: increased serum antibodies as an independent risk factor?

The relationship between H. pylori and functional dyspepsia is controversial. Hypothesizing that subjects with a more intense immune response to H. pylori (and hence higher antibody titers) would be at greater risk of dyspepsia, we aimed to identify risk factors for the development of dyspeptic symptoms. In all, 491 healthy blood donors with no history of peptic ulceration and 74 consecutive patients with a confirmed diagnosis of functional dyspepsia were studied. Symptoms and potential risk factors [nonsteroidal antiinflammatory drugs (NSAIDs), alcohol, and smoking] were measured by a validated questionnaire. H. pylori status was determined by IgG antibodies using a validated ELISA test with a cutoff titer for a positive serology of 10 units/ml. Logistic regression analysis assessed the association between risk factors and dyspepsia. Among blood donors, 21% (95% CI 17.6-24.8) reported dyspepsia (pain localized to the upper abdomen); 7.7% (95% CI 5.5-10.4) had frequent dyspepsia (>6 times in the prior year). The age-adjusted prevalence of H. pylori was not significantly different in blood donors with (39.5%, 95% CI 24.0-56.6) and without frequent dyspepsia (34.2%, 95% CI 29.8-38.36), but was significantly greater in patients with functional dyspepsia (68.8%, 95% CI 57.3-77.9). In the combined study population of blood donors and patients with functional dyspepsia, logistic regression adjusting for age identified the following independent risk factors for frequent dyspepsia: high serum antibody levels against H. pylori (OR for IgG titer >50 units/ml vs H. pylori titers 11-50 units/ml 4.6, 95% CI 2.7-7.8) and consumption of standard NSAIDs (OR 2.4,95% CI 1.3-4.5). In contrast, alcohol (OR 0.6, 95% CI 0.3-1.0), smoking (OR 1.5, 95% CI 1.0-2.3) or positive H. pylori serology with titers < or = 50 units/ml (OR 1.6, 95% CI 0.8-2.9) were not associated with frequent dyspepsia. In conclusion, in a subgroup of H. pylori-infected subjects who have high antibody titers, H. pylori appears to be associated with functional dyspepsia.

Prevalence of peptic lesions in asymptomatic, healthy volunteers

AIM

To investigate the presence of lesions of the upper gastrointestinal tract of asymptomatic, healthy volunteers undergoing clinical pharmacology studies.

MATERIAL AND METHODS

A series of 53 volunteers (45 male, 23 Helicobacter pylori negative and 30 Helicobacter pylori positive) underwent upper gastrointestinal endoscopy. Helicobacter pylori status was assessed using two methods (rapid urease test and histology) from antral and corpus biopsies.

RESULTS

Peptic lesions were found in 24 (45%) subjects: erosive oesophagitis, gastric/duodenal ulcers and gastric/duodenal erosions were found in 23%, 9% and 36% of these volunteers, respectively. Helicobacter pylori-positive subjects had significantly (p<0.05) more gastroduodenal lesions than Helicobacter pylori negative individuals (12/30 vs 3/23). The presence of peptic ulcers and erosive oesophagitis was similar in Helicobacter pylori-positive and -negative individuals.

CONCLUSIONS

The possibility that peptic lesions might exist in otherwise asymptomatic, healthy individuals cannot be ruled out. Helicobacter py lori-positive individuals have a significantly higher incidence of gastric and duodenal lesions than Helicobacter pylori negative subjects.

Fundal gastritis as a potential cause of reflux oesophagitis

The transient lower oesophageal sphincter relaxations which allow reflux may be due to altered afferent pathways from the fundus. We aimed to determine whether fundal inflammation is the underlying cause. Two endoscopic biopsies were taken from each of the gastric antrum and fundus in 25 asymptomatic controls with a normal endoscopy (median age 54 range 13-83 years), and 33 patients with erosive oesophagitis (median age 52, 11-78 years). No patient had taken acid suppression therapy or antibiotics for at least 1 month. Sections were stained with haematoxylin and eosin and Giemsa stain and examined in a blinded fashion by one pathologist for the presence of gastritis (Sydney classification) and Helicobacter pylori. Chronic gastritis was common in both groups, but was usually mild. In Helicobacter pylori-negative subjects, there was significantly less chronic gastritis in the antrum and the fundus in oesophagitis patients than in controls (p < 0.05). When present, gastric atrophy was usually antral and mild in severity. There was no difference in the incidence of gastric atrophy in patients with oesophagitis compared with controls (24% compared with 40%; p > 0.05). Chronic gastritis is not more common in patients with oesophagitis, and is unlikely to play a part in the pathogenesis of this disease.

Helicobacter pylori effects on gastritis, gastrin and enterochromaffin-like cells in Zollinger-Ellison syndrome and non-Zollinger-Ellison syndrome acid hypersecretors treated long-term with lansoprazole

BACKGROUND

Helicobacter pylori is said to cause atrophy of the gastric corpus and enterochromaffin-like cell proliferation in gastro-oesophageal reflux disease (GERD) patients treated long-term with a proton pump inhibitor.

AIMS

To determine the effect of H. pylori infection on gastritis, enterochromaffin-like cell density and hyperplasia, mucosal atrophy and serum gastrin in patients with gastric hypersecretion (basal acid output gt; 15 mmol/h) with either hypergastrinemia (Zollinger-Ellison syndrome) or normal gastrin (non-Zollinger-Ellison syndrome) before and during long-term treatment with lansoprazole.

METHODS

Lansoprazole was individually titrated to reduce basal acid output to < 5 mmol/h (< 1 mmol/h in post-surgical Zollinger-Ellison syndrome). Gastric corpus biopsies were obtained every 6 months before treatment and up to 8 years later.

RESULTS

H. pylori was present in corpus biopsies in approximately 50%, causing active gastritis which resolved rapidly in 15 subjects after elimination of H. pylori. Patchy mild/moderate corpus atrophy was present at entry in two and at the end in four out of 60 patients, one being H. pylori-positive. Intestinal metaplasia (< 10%) was seen in six isolated biopsies (1% of total). H. pylori did not affect serum gastrin, enterochromaffin-like cell density or hyperplasia. Enterochromaffin-like cell density was twice as high in Zollinger-Ellison syndrome as in non-Zollinger-Ellison syndrome patients (241 vs. 126 cells/mm2, P < 0.001). Enterochromaffin-like cells remained normal in the non-Zollinger-Ellison syndrome hypersecretors regardless of H. pylori status.

CONCLUSION

Corpus enterochromaffin-like cell increases were related to serum gastrin elevation, but neither H. pylori nor long-term treatment with lansoprazole alone or together had any effect on enterochromaffin-like cell density or hyperplasia. Corpus acute gastritis resulted from H. pylori infection, but did not result in mucosal atrophy despite long-term proton pump inhibitor treatment and promptly resolved with loss of H. pylori.

Dyspepsia is associated with CagA-positive Helicobacter pylori

OBJECTIVE

The role of Helicobacter pylori in nonulcer dyspepsia is controversial. Speculation has arisen that only strains of H. pylori carrying the CagA virulence factor are important in the development of dyspepsia. The objective of this study was to determine whether nonulcer dyspepsia correlated with CagA-positive H. pylori infection.

METHODS

A total of 435 healthy blood donors and 102 general medicine clinic respondents completed the Bowel Disease Questionnaire and the PRIME-MD survey, a validated screen for common psychiatric disorders. Subjects were classified as cases of nonulcer dyspepsia if they reported pain in the upper abdomen more than six times in the previous year and denied a past or current history of peptic ulcer disease. Study participants were tested for IgG antibodies to H. pylori and the CagA protein.

RESULTS

Clinic respondents were more likely than healthy blood donors to meet the case definition for nonulcer dyspepsia (34% vs 13%, p < 0.001), to be seropositive for H. pylori (54% vs 18%, p < 0.001), and to be CagA seropositive (41% vs 10%, p = 0.01). Logistic regression identified CagA seropositivity (p = 0.03), race (p = 0.001), and positive screens for depression (p = 0.007) or somatization (p < 0.001) as variables independently associated with nonulcer dyspepsia.

CONCLUSION

Infection with a CagA-positive strain of H. pylori is associated with a clinical diagnosis of nonulcer dyspepsia. However, nonulcer dyspepsia was also strongly and independently associated with positive screens for depression or somatization disorder as well as with ethnicity. These potential sources of variance should be considered in the design of future studies evaluating nonulcer dyspepsia.

Accurate diagnosis of Helicobacter pylori. Stool tests

From the limited data available, it seems that the H. pylori stool assay represents a highly accurate diagnostic tool to detect H. pylori infection before and shortly after therapy. As a test that is noninvasive, accurate, simple, and cost-effective, the H. pylori stool assay has the potential to become the preferred diagnostic tool in many different clinical settings from epidemiologic studies to pediatric investigations, from pre-endoscopic screening policies to posttherapy monitoring.

The prevalence of Helicobacter pylori: are emergency medicine residents at risk?

Helicobacter pylori is strongly associated with peptic ulcer disease and gastric cancer. It is a cause of chronic active gastritis. Our hypothesis was that Emergency Physicians might be at increased risk for infection due to their exposure to gastric contents from procedures performed in the Emergency Department. Our goal was to test a group of Emergency Physicians for H. pylori infection. In this cross sectional study, we tested a group of volunteers from an Emergency Medicine residency program for H. pylori infection by serum analysis for IgG. A matched control group was also tested. Forty-five subjects were enrolled; one subject's sample was lost. Three of 44 subjects (6.8%) were positive for H. pylori antibodies. Seven of 44 controls (15.9%) tested positive. Thus, Emergency Physicians do not have increased H. pylori infection rates and may be at less risk than the general population. Routine testing is not recommended.

Seroconversion and seroreversion in IgG antibodies to Helicobacter pylori: a serology based prospective cohort study

STUDY OBJECTIVES

To assess the incidence of seroconversion and seroreversion in IgG antibodies to Helicobacter pylori within a 11 year observation period using these events as markers for acquisition and loss of the infection, respectively.

DESIGN

Population based prospective cohort study.

SETTING

Northern part of Copenhagen County, Denmark.

PARTICIPANTS AND METHODS

A random sample of 2527 Danish adults were examined and blood obtained in 1983 and in 1994. Matching pairs of sera were analysed for the presence of IgG and IgM antibodies to H pylori with an in house enzyme linked immunosorbent assay. Participants who were seronegative at study entry and seropositive at follow up and had a fourfold increase in baseline IgG antibody levels were categorised as seroconverters and regarded as having acquired H pylori infection. Participants who were seropositive at study entry and had at least a fourfold decrease in baseline IgG antibody levels at follow up were assumed to have lost the infection (seroreverters).

RESULTS

The seroprevalence of H pylori infection was 24.7 (95% confidence intervals (95% CI) 23.0, 26.4) % in 1983 and 24.5 (95% CI 22.8, 26. 2) % in 1994. A total of 14 participants seroconverted within the observation period (cumulative 11 year incidence proportion: 1.0 (95% CI 0.5, 1.5) %). Having increased IgM antibody levels at study entry significantly increased the likelihood of IgG seroconversion (relative risk 6.4 (95% CI 2.1, 19.6). Seroreversion was seen in 48 participants (cumulative 11 year incidence proportion: 7.7 (95% CI 5. 6, 9.8) %).

CONCLUSIONS

Changes in H pylori infection status with time are rare in Danish adults. Few adults become infected with H pylori in Denmark.

Effect of population screening and treatment for Helicobacter pylori on dyspepsia and quality of life in the community: a randomised controlled trial. Leeds HELP Study Group

BACKGROUND

Infection with Helicobacter pylori is the main cause of peptic-ulcer disease. Treatment of this infection might lower the prevalence of dyspepsia in the community and improve quality of life. We investigated this possibility in a double-blind randomised controlled trial.

METHODS

Individuals aged 40-49 years were randomly selected from the lists of 36 primary-care centres. A researcher interviewed participants with a validated dyspepsia questionnaire and the psychological general wellbeing index (PGWB). H. pylori status was assessed by the carbon-13-labelled urea breath test. Infected participants were randomly assigned active treatment (omeprazole 20 mg, clarithromycin 250 mg, and tinidazole 500 mg, each twice daily for 7 days) or identical placebo. Participants were followed up at 6 months and 2 years.

FINDINGS

Of 32,929 individuals invited, 8455 attended and were eligible; 2324 were positive for H. pylori and were assigned active treatment (1161) or placebo (1163). 1773 (76%) returned at 2 years. Dyspepsia or symptoms of gastro-oesophageal reflux were reported in 247 (28%) of 880 in the treatment group and 291 (33%) of 871 in the placebo group (absolute-risk reduction 5% [95% CI 1-10]). H. pylori treatment had no significant effect on quality of life (mean difference in PGWB score between groups 0.86 [-0.33 to 2.05]).

INTERPRETATION

Community screening and treatment for H. pylori produced only a 5% reduction in dyspepsia. This small benefit had no impact on quality of life.

Increased prevalence of precancerous changes in relatives of gastric cancer patients: critical role of H. pylori

BACKGROUND & AIMS

Helicobacter pylori is believed to predispose to gastric cancer by inducing gastric atrophy and hypochlorhydria. First-degree relatives of patients with gastric cancer have an increased risk of developing gastric cancer. The aim of this study was to determine the prevalence of atrophy and hypochlorhydria and their association with H. pylori infection in first-degree relatives of patients with gastric cancer.

METHODS

H. pylori status, gastric secretory function, and gastric histology were studied in 100 first-degree relatives of patients with noncardia gastric cancer and compared with those of controls with no family history of this cancer.

RESULTS

Compared with healthy controls, relatives of patients with gastric cancer had a higher prevalence of hypochlorhydria (27% vs. 3%) but a similar prevalence of H. pylori infection (63% vs. 64%). Relatives of cancer patients also had a higher prevalence of atrophy (34%) than patients with nonulcer dyspepsia (5%) matched for H. pylori prevalence. Among the relatives of cancer patients, the prevalence of atrophy and hypochlorhydria was increased only in those with evidence of H. pylori infection, was greater in relatives of patients with familial cancer than in relatives of sporadic cancer index patients, and increased with age. Eradication of H. pylori infection produced resolution of the gastric inflammation in each subject and resolution of hypochlorhydria and atrophy in 50% of the subjects.

CONCLUSIONS

Relatives of patients with gastric cancer have an increased prevalence of precancerous gastric abnormalities, but this increase is confined to those with H. pylori infection. Consequently, prophylactic eradication of the infection should be offered to such subjects.

Anti-CagA reactivity in Helicobacter pylori-negative subjects: a comparison of three different methods

Emerging evidence suggests that infection by CagA-positive Helicobacter pylori strains is related to the development of more serious gastroduodenal diseases, thus conferring to the determination of anti-CagA antibodies a relevant clinical significance in serological screenings. The detection of anti-CagA positivity in sera negative for anti-H. pylori antibodies raises the question of whether this apparently nonsense result is merely due to a false positive reaction. To address this issue, we compared three different methods for the detection of anti-CagA antibodies. In all, 272 selected sera from patients with precisely defined H. pylori status (positive or negative concordance of five tests, ie, histology by Giemsa in both antrum and corpus, rapid urease test, culture, [13C]urea breath test, IgG ELISA) were tested for anti-CagA reactivity by three different techniques (western immunoblotting, ELISA, and recombinant immunoblotting assay). In order to assess the sensibility and specificity of each tests, we considered as "true" anti-CagA positive sera those with two out of three positive results. Sera from 70% of H. pylori-positive patients and 10% from H. pylori-negative patients turned out to be "true" positives for anti-CagA antibodies. The three methods showed similar excellent results, in terms of both sensitivity and specificity, always over 93%. It is confirmed that a proportion of patients with a negative conventional serology against H. pylori possess anti-CagA antibodies in their sera. In this paper we demonstrate that it can happen even in patients without any biological signs of actual H. pylori infection. The possibility that this can be due to a false positive laboratory result is very likely ruled out by the accuracy of the three methods used. The clinical management of these patients needs further study on larger series.

Diagnosis of Helicobacter pylori infection with a new non-invasive antigen-based assay. HpSA European study group

BACKGROUND

Helicobacter pylori is a common human pathogen implicated in certain gastrointestinal diseases. In the search for new non-invasive techniques to diagnose H. pylori infection, we evaluated an EIA for H. pylori antigen in stool (HpSA).

METHODS

In a prospective multicentre study, stool specimens from 501 patients (276 men, 225 women; age range 17-88 years, mean 52) undergoing gastroscopy in 11 centres throughout Europe were tested with HpSA and the carbon-13-urea breath test. At endoscopy, four biopsy samples were taken for histology (haematoxylin and eosin) and H. pylori detection (giemsa in both antrum and corpus, culture and rapid urease test). Patients were defined as positive for H. pylori if histology (antrum, corpus, or both) and urease test were positive, or if culture was positive. Patients classified as having H. pylori infection received an eradication regimen; 107 were reassessed 4 weeks after therapy.

FINDINGS

Of 272 patients with H. pylori infection by the predefined criteria, 256 were positive by HpSA (sensitivity 94.1% [95% CI 90.6-96.6]). Of 219 patients without infection, 201 were negative by HpSA (specificity 91.8% [87.3-95.1]).

INTERPRETATION

The stool assay was a reliable and easy-to-use tool for diagnosis of H. pylori infection. The test was accurate even shortly after treatment.

High prevalence of Helicobacter pylori infection in shepherds

It has been suggested that Helicobacter pylori infection may, in some instances, be a zoonosis. The aim of this study was to evaluate the prevalence of H. pylori infection in Sardinian shepherds and their families in relation to exposure to sheep and sheep dogs. Sardinian shepherds and a control group of blood donors completed detailed questionnaires regarding demographics, childhood and current economic status, and the presence of symptoms related to the upper gastrointestinal tract. H. pylori status was determined by a sensitive ELISA for anti-H. pylori IgG and by western blot for anti-CagA IgG. A subgroup of shepherds had upper gastrointestinal endoscopy with biopsy to assess the severity of the gastritis. H. pylori infection in Sardinian shepherds approached 100% and was positively related to animal contact (98% of shepherds, 73% of family members without regular direct animal contact compared to 43% of blood donors) (P < 0.001). Importantly, the family members shared the same childhood with the shepherds but choose different careers (e.g., teachers, nurses, business) and did not have regular contact with sheep. In conclusion, the prevalence of H. pylori infection in Sardinian shepherds is among the highest in the world and is associated with direct contact with sheep and sheep dogs. These results suggest that the cycle of H. pylori infection might, in certain circumstances, include phases in the environment, animals (sheep or dogs) and human beings.

Incidence of Helicobacter pylori infection in a cohort of Italian military students

Prevalence and incidence of Helicobacter pylori infection among 250 Italian military students were studied using specific IgG antibodies. Subjects susceptible at enrollment were evaluated during a 10-month follow-up period, when two serum samples were collected after 5 and 10 months, respectively. Samples were also analyzed for anti-CagA (a protein associated with virulent H. pylori strains) IgG antibodies. Finally, spectrotypic analysis by isoelectric focusing and reverse blotting (IEFRB) was performed in the majority of positive samples. Forty-three out of 250 (17.2%) were positive at the time of enrollment, a seroprevalence rate very similar to that observed in a larger Italian military population 5 years earlier. Among the 207 susceptible subjects, two seroconverted at 5 months after enrollment; they were still positive at the end of follow-up (incidence rate of 1.16 per 100 person/years of exposure). This data suggests a spread of H. pylori in the Italian military population that is not negligible. Nearly all anti-H. pylori-positive subjects were also CagA antibody positive (agreement percentage: 97.6%; K = 0.91), suggesting that the large majority of H. pylori strains were of the virulent type. Sixty-four percent of positive sera presented an oligoclonal spectrotype, which seems to be a hallmark of humoral immune response to H. pylori.

Helicobacter pylori infection and cytotoxic antigen associated gene "A" status in short children

BACKGROUND

Helicobacter pylori is now an accepted gastroduodenal pathogen and is being investigated for possible implications in nongastroenterological conditions such as growth impairment. Subjects infected by cytotoxic Cag-A positive strains seem more likely to develop serious gastroduodenal diseases but the possible role of Cag-A positive strains in non gastroenterological diseases has not been fully investigated.

OBJECTIVE

1) To evaluate the prevalence of Helicobacter pylori infection and Cag-A positivity in short children compared to auxologically normal children. All the subjects were without gastro-intestinal symptoms and were not obese or significantly underweight. 2) To verify the reliability of the ELISA assay for H. pylori.

SUBJECTS

H. pylori infection was assessed in 338 children, 182 auxologically normal and 156 short children, with and without deficiency in growth hormone, by the determination of specific IgG antibody. In 79 subjects (all seropositive and a random sample of seronegative children), 13C-urea breath test and cytotoxic Cag-A positive strains were examined.

RESULTS

The overall seroprevalence of H. pylori infection by IgG antibody was 18/156 (11.5%) and 13/182 (7.1%) in short and auxologically normal children respectively. The 13C-urea breath test was positive in 29 children: 17 (10.9%) short and 12 (6.6%) auxologically normal. Western blotting documented infection by cytotoxic Cag-A positive strains in 12/17 (70.6%) and 8/12 (66.6%) of short and auxologically normal children respectively. None of the differences between the two groups were significant.

CONCLUSIONS

1) We found a similar prevalence of H. pylori infection and Cag-A positivity in two large pediatric populations of short or auxologically normal children. Therefore: 1) Our data did not confirm a role of H. pylori infection in short stature in children. 2) We found a high reliability of ELISA assay for the detection of IgG antibodies compared to breath test.

Clinical significance of Helicobacter pylori seropositivity and seronegativity in asymptomatic blood donors

To determine the clinical significance of Helicobacter pylori seropositivity and seronegativity in healthy blood donors, we carried out a serological evaluation of Helicobacter pylori status and endoscopy in a healthy blood donors population. In all, 1010 donors were screened for Helicobacter pylori by IgG ELISA and assessed for pepsinogen I and gastrin levels by RIA; 298 IgG seropositive and 61 seronegative subjects underwent endoscopy with biopsies. Of 359, 165 were also tested for CagA by western blotting. Of the 298 IgG seropositives, 274 were shown to be infected on biopsy testing. Endoscopy revealed 70 peptic ulcers, 41 cases of erosive duodenitis, and two gastric cancers. In all 105 seropositive donors were tested for CagA and 69 were CagA positive [34/58 gastritis (58.6%), 24/35 duodenal ulcer (68.6%) and 11/12 gastric ulcer (91.6%)]. Histologically active/chronic gastritis was associated with CagA: 88.4% vs 50% (CagA seropositive vs seronegative). Of the 61 IgG seronegatives, 59 were negative on biopsy testing. At endoscopy three had duodenitis. Of the 60/61 IgG seronegatives tested for CagA, one had a moderate reaction. Duodenal ulcer donors showed higher pepsinogen I levels than donors without duodenal ulcers (97.7 microg/ml vs 80.9 microg/ml respectively). Screening for Helicobacter pylori and anti-CagA seropositivity and pepsinogen I can identify individuals likely to have gastroduodenal pathology even in the absence of symptoms.

Treatment of functional dyspepsia

Many functional dyspepsia treatment trials have until recently suffered from important weaknesses in study design. A major problem has been the low number of studies that have used validated outcome measures. Fortunately, progress has been made in this area. The evidence for the efficacy of antacids, H2-receptor antagonists, omeprazole, domperidone, cisapride and anti-Helicobacter therapy is reviewed. Although several of these have shown benefit, it is unclear whether this may be a result of the inclusion of patients with unrecognized gastro-oesophageal reflux disease. The data on anti-Helicobacter therapy are conflicting.

Helicobacter pylori and peptic ulcer disease. Current evidence for management strategies

OBJECTIVE

To review current evidence for primary care physicians who manage Helicobacter pylori in peptic ulcer disease.

QUALITY OF EVIDENCE

MEDLINE was searched to August 1997 for randomized controlled trials, systematic overviews, and consensus reports. High-quality recent reviews were often found. Randomized controlled trials presented as abstracts at recent meetings were reviewed.

MAIN FINDINGS

Helicobacter pylori is found in most case of duodental and gastric ulcer, and eradication of H pylori leads to "cure" of ulcer disease and prevention of ulcer complications. Eradication of H pylori is not indicated for gastroesophageal reflux disease. No evidence indicates that screening asymptomatic individuals for H pylori infection reduces the risk of subsequent development of gastric cancer. Controversial areas are the role of H pylori in functional dyspepsia and screening for H pylori before initiating nonsteroidal anti-inflammatory drugs. In primary care, H pylori can be detected using serologic tests or urea breath tests (UBT), but only UBTs can be used to confirm eradication. Whether patients suspected of having ulcers can be managed with an H pylori test-and-treat strategy without initial investigation is controversial. The first-line recommended treatment is 1 week of twice daily triple therapy with a proton pump inhibitor, clarithromycin (Biaxin), and amoxicillin (e.g., Amoxil), or metronidazole (Flagyl).

CONCLUSIONS

Helicobacter pylori eradication should be first-line therapy in primary care for infected patients with peptic ulcers. Effective H pylori testing methods and treatments are now available.

Testing for Helicobacter pylori in primary care: trouble in store?

STUDY OBJECTIVE

To assess the role of testing for Helicobacter pylori in the management of dyspeptic patients in primary care.

DESIGN

Selective review of literature frequently quoted to support use of H pylori testing.

MAIN RESULTS

Testing for H pylori and referral of only positive cases for endoscopy aims to reduce the number of "unnecessary" endoscopies. Patients with negative results may receive short-term reassurance and subsequently place fewer demands on health services. However, studies to date have only assessed this practice in secondary care settings. Given the relatively high prevalence of both dyspepsia and H pylori infection, the transfer of this practice to primary care may lead to a paradoxical increase in endoscopy referrals. Identification of H pylori and prescribing of eradication treatment also aims to reduce endoscopy referrals. No primary care trials have yet assessed this approach. Given that fewer than one in four of dyspeptic patients have peptic ulceration, a high proportion may fail to respond to eradication treatment and subsequently require referral for endoscopy. The longer term clinical and psychosocial sequelae of treating or labelling patients with an infection associated with gastric cancer remain unknown.

CONCLUSIONS

Given uncertainty concerning the possible adverse effects of H pylori testing in primary care, we suggest a moratorium on its use in this setting until results from relevant clinical trials become available.

Rabeprazole in treatment of acid peptic diseases: results of three placebo-controlled dose-response clinical trials in duodenal ulcer, gastric ulcer, and gastroesophageal reflux disease (GERD). The Rabeprazole Study Group

Rabeprazole, a new proton pump inhibitor, was studied in patients with acid-peptic-related diseases (duodenal ulcer, gastric ulcer, GERD) in three placebo-controlled, double-blind, randomized clinical trials. Men and women over the age of 18 were enrolled if the presence of an active duodenal or gastric ulcer or erosive or ulcerative esophagitis was confirmed on upper gastrointestinal endoscopy. Patients were randomly allocated to either placebo or rabeprazole 20 mg or 40 mg in the duodenal and gastric ulcer protocols or to placebo or rabeprazole 10 mg, 20 mg, or 40 mg in the GERD protocol. All doses of rabeprazole in all three studies were statistically significantly superior to placebo in healing acid-related lesions. There were no treatment differences between the rabeprazole doses in healing active peptic lesions. The incidence of positive [13C]urea breath test for H. pylori was 53% in patients with duodenal or gastric ulcers. H. pylori status was not effected by treatment with rabeprazole.

High prevalence of Helicobacter pylori in liver cirrhosis: relationship with clinical and endoscopic features and the risk of peptic ulcer

In 153 consecutive patients with cirrhosis we assessed: (1) the prevalence of IgG to Helicobacter pylori and compared it with that found in 1010 blood donors resident in the same area; and (2) the relationships of IgG to Helicobacter pylori with clinical and endoscopic features and with the risk of peptic ulcer. The IgG to Helicobacter pylori prevalence of cirrhotics was significantly higher than in blood donors (76.5% vs 41.8%; P < 0.0005) and was not associated with sex, cirrhosis etiology, Child class, gammaglobulins and hypertensive gastropathy. In both groups, the prevalence of IgG to Helicobacter pylori was significantly higher in subjects over 40. Among patients with cirrhosis a significantly higher prevalence of Helicobacter pylori was found in patients with previous hospital admission (P = 0.02) and/or upper gastrointestinal endoscopy (P = 0.01) and patients with peptic ulcer (P = 0.0004). Multivariate analysis identified increasing age and male sex as risk factors for a positive Helicobacter pylori serology and no independent risk factors for peptic ulcer. The high prevalence of Helicobacter pylori-positive serology found in the present series is related to age and sex and might also be explained by previous hospital admissions and/or upper gastrointestinal endoscopy. Our results do not confirm the role of Helicobacter pylori as risk factor for peptic ulcer in patients with liver cirrhosis.

A serologic survey of Helicobacter pylori infection in 3281 Italian patients endoscoped for upper gastrointestinal symptoms. The Italian Helicobacter Pylori Study Group

AIM

To assess the seroprevalence of Helicobacter pylori infection in a large series of patients with upper gastrointestinal symptoms referred for their first upper gastrointestinal endoscopy, and to evaluate any association with disease.

METHODS

A large survey of 3281 dyspeptic patients undergoing their first endoscopic examination was undertaken, involving 93 centres in Italy. A blood sample was taken from each participant, for measuring IgG antibodies against H. pylori using a commercially available kit, and two biopsies of the antral gastric mucosa were obtained for evaluating a Giemsa-stained specimen.

RESULTS

Endoscopic macroscopic diagnoses included normal mucosa (25.3%), gustroduodenitis (51.6%), gastric and duodenal ulcers (3.7 and 14.9%, respectively) and other conditions, including gastric cancer (0.8%). Overall, the seroprevalence result was 71.3% with a strong positive association with increasing age and male sex and a negative one with educational level. According to endoscopic diagnoses, the association with H. pylori seropositivity was highest for duodenal and gastric ulcer (multivariate odds ratio: 6.1 and 2.2) and lowest for carcinoma. The comparison between the results of serology and the single Giemsa-stained specimen showed good reliability of H. pylori IgG, particularly in a subgroup (n = 2056) for which the interpretation was performed by a single dedicated pathologist: sensitivity and specificity were 92 and 78%, respectively.

CONCLUSION

Commercial IgG serology is a reliable tool for the assessment of H. pylori infection in large-scale multicentre surveys. A very high seroprevalence among dyspeptic patients was confirmed, particularly in the presence of peptic disease. Factors associated with the infection were very similar to those usually reported in the general population, but male patients showed a significantly higher prevalence.