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Helicobacter Pylori Infections (helicobacter + pylori_infections)
Selected AbstractsProblem of Distinguishing False-Positive Tests from Acute or Transient Helicobacter pylori InfectionsHELICOBACTER, Issue 2 2006Zhannat Z. Nugalieva Abstract Background:, Reliable detection of acute Helicobacter pylori infections remains problematic. The high prevalence of false-positive non-invasive tests in low H. pylori prevalence populations makes identification of acute and transient infections difficult. Methods:, We explored the use of serum pepsinogens (PG) for diagnosis of acute infection in patients following H. pylori challenge such that the onset of the infection was known. We then compared those findings to a group of children with presumed acute infections defined as a positive urea breath test (UBT) and negative IgG serology. Results:, We examined the pattern and calculated cut-off values of PG levels in 18 adult volunteers with known acute H. pylori infection. We then compared the results with sera from nine symptomatic children with presumed acute H. pylori infection and a matched control group of nine children who did not meet criteria for acute H. pylori infection. In acute infection, both PGI and II levels increased following H. pylori infection reaching a peak by 2 weeks post-infection. The frequency of a positive test defined as a value > mean +2 SD was 17, 71, and 94% at week 1, 2, and 4 post-infection, respectively. Only one child with presumed acute H. pylori infection had an elevated serum PGI and one had an elevated PGII. Five of the children had follow-up UBTs and four were negative consistent with the diagnosis of false-positive UBT. H. pylori infection was confirmed in the child with an elevated PGI level. Conclusions:, These data suggest that a single positive noninvasive test in populations of low prevalence is most likely a false-positive result. This suggests that a single positive test requires confirmation preferably using a test that measures a different parameter (e.g., UBT confirmed by stool antigen test). It appears that most "transient"H. pylori infections are diagnosed on the basis of false-positive tests. PG levels are possible candidates as the confirmatory test. [source] Age at Acquisition of Helicobacter pylori in a Pediatric Canadian First Nations PopulationHELICOBACTER, Issue 2 2002Samir K. Sinha Abstract Background. Few data exist regarding the epidem-iology of Helicobacter pylori infections in aboriginal, including the First Nations (Indian) or Inuit (Eskimo) populations of North America. We have previously found 95% of the adults in Wasagamack, a First Nations community in Northeastern Manitoba, Canada, are seropositive for H. pylori. We aimed to determine the age at acquisition of H. pylori among the children of this community, and if any association existed with stool occult blood or demographic factors. Materials and Methods. We prospectively enrolled children resident in the Wasagamack First Nation in August 1999. A demographic questionnaire was administered. Stool was collected, frozen and batch analyzed by enzyme-linked immunosorbent assay (ELISA) for H. pylori antigen and for the presence of occult blood. Questionnaire data were analyzed and correlated with the presence or absence of H. pylori. Results. 163 (47%) of the estimated 350 children aged 6 weeks to 12 years, resident in the community were enrolled. Stool was positive for H. pylori in 92 (56%). By the second year of life 67% were positive for H. pylori. The youngest to test positive was 6 weeks old. There was no correlation of a positive H. pylori status with gender, presence of pets, serum Hgb, or stool occult blood. Forty-three percent of H. pylori positive and 24% of H. pylori negative children were < 50th percentile for height (p = 0.024). Positive H. pylori status was associated with the use of indoor pail toileting (86/143) compared with outhouse toileting (6/20) (p = 0.01). Conclusions. In a community with widespread H. pylori infection, overcrowded housing and primitive toileting, H. pylori is acquired as early as 6 weeks of age, and by the second year of life 67% of children test positive for H. pylori. [source] Anti- Helicobacter pylori therapy in India: Differences in eradication efficiency associated with particular alleles of vacuolating cytotoxin (vacA) geneJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 2 2003SUJIT CHAUDHURI Abstract Background and Aims:, The efficiency of Helicobacter pylori eradication varies geographically, as do many parameters that might affect therapeutic efficiency, including bacterial genotype. The aim of the present study was to determine the efficiency of H. pylori eradication using a 10-day proton pump inhibitor-based triple-therapy regimen (omeprazole, clarithromycin and amoxycillin) in an eastern Indian patient population, and to find out the relationship, if any, of the success or failure of the therapy to known features of bacterial genotype. Methods,Helicobacter pylori infections were analyzed in 66 duodenal ulcer patients by upper gastrointestinal endoscopy, rapid urease tests, histology and culture. The cytotoxin-associated gene (cagA) and vacuolating cytotoxin (vacA) gene status of cultured strains were studied by polymerase chain reaction. Treatment was given for 10 days and endoscopy was repeated at 4 and 12 weeks post therapy to monitor ulcer healing and H. pylori eradication. Results:, Ulcer healing was observed in 60 patients (96.77%). Helicobacter pylori was eradicated in 41 (62.12% intention to treat, 66.13% per protocol) of the 66 duodenal ulcer patients, but not in the other 25. The bacteria from 47 patients were genotyped. The only significant disease-associated difference in patterns observed was that the vacA m1 allele was represented more disproportionately among patients with eradication failures (68%) than in those with successful eradication (39%) (P < 0.05) No significant association of vacAs1 (signal sequence allele) or cag pathogenicity island status with persistence was detected. Conclusions:, This study highlights the public health need for cheaper, more cost-effective anti- H. pylori therapies for developing countries, and suggests that subtle features of bacterial genotype can influence therapeutic efficiency. The possibility that particular vacA mid region alleles affect persistence, perhaps through toxin action on particular gastric cell types, merits further study. [source] CHARACTERISTIC OF GASTRIC CANCER IN INDONESIA: THE ROLE OF HELICOBACTER PYLORI INFECTIONJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 12 2000Murdani Abdullah Background Gastric cancer is the second most common fatal malignancy in the world. In 1996, approximately one million new cases of gastric cancer were found. It is generally agreed that the pathogenesis is multifactorial which may include, dietary factors, environmental factors, bacterial and viral infections. Aim to evaluate the frequent of gastric cancer in Indonesia and itís relating factors. Methods A sample size of 7902 subjects were determined based on hospital data of dyspeptic patients following gastroduodenoscopy procedure from January 1997 to September 1999. Patients were recruited from 9 endoscopic centers located in 5 cities in Indonesia. Endoscopic biopsy specimens were taken 2 specimens from the antrum (2 cm from pylorus) and 2 specimens from the corpus. Helicobacter pylori infections were determined by serology (ELISA), rapid urea test (CLO test), or histopathology examination using Haematoxyline Eosin and Giemsa staining. The criteria used to diagnose Helicobacter pylori infection were a positive result either from one of these tests and/or in combination. Results The frequent of proximal gastric cancer and distal gastric cancer finding were 0.63 % and 0.54 %, consecutively. In the proximal and distal gastric cancer groups the present of Helicobacter pylori were 55.77 % and 85.36 %, consecutively (p>0.05). The finding of gastric cancer among ethnic groups were 0.65 % for Chinese ethnicity and 0.81 % for Non-Chinese ethnicity, statistically has no significant different (p=0,9514). The distal-to-proximal gastric cancer ratio was 0.85. The proximal gastric cancer more frequent to be found in the age group of 41-60 years old (47.83%), while the distal gastric cancer in the age group of 51-70 years old (61.54%). Conclusion The distal-to-proximal gastric cancer ratio was 0.85. The present of Helicobacter pylori were lower in proximal gastric cancer rather than distal gastric cancer, but statistically has of no significant. [source] Diagnostic yield of oesophagogastroduodenoscopy in children with abdominal painALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2009K. THAKKAR Summary Background, Abdominal pain is the most common indication for oesophagogastroduodenoscopy (OGD) in children. However, existing studies examining the diagnostic outcomes of OGD in children with abdominal pain are limited. Aim, To examine the diagnostic yield of OGD with biopsy in the evaluation of abdominal pain and to describe the endoscopic and histological findings in patients undergoing OGD for abdominal pain of unclear aetiology. Methods, We performed a retrospective cross-sectional cohort study in children under 18 years of age who had OGD for the primary indication of abdominal pain, at Texas Children's Hospital and Children's Hospital of The King's Daughters from 1 January 2002 to 30 June 2005. Results, Overall, OGD was diagnostic in 454 (38.1%) of the 1191 procedures, including reflux oesophagitis (23%, n = 271), Helicobacter pylori infections (5%, n = 55), peptic ulcers (3%, n = 32), eosinophilic oesophagitis (2%, n = 25), celiac disease (1%, n = 9) and Crohn's disease (0.5%, n = 7). Male gender, older age, elevated C-reactive protein and vomiting were associated with increased diagnostic yield. Conclusions, Our findings suggest that OGD is valuable for the evaluation of chronic abdominal pain in children, with a diagnostic yield of 38%. The majority of alarm symptoms and routine laboratory tests are not significantly associated with diagnostic yield. [source] Meta-analysis: the efficacy, adverse events, and adherence related to first-line anti- Helicobacter pylori quadruple therapiesALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2004L. A. Fischbach Summary Background :,Owing to rising drug-resistant Helicobacter pylori infections, currently recommended proton-pump inhibitor-based triple therapies are losing their efficacy, and regimens efficacious in the presence of drug resistance are needed. Aims :,To summarize the efficacy, safety and adherence of first-line quadruple H. pylori therapies in adults. Methods :,Meta-regression models identified factors explaining variation in the efficacy of first-line quadruple therapies from 145 treatment arms. Estimates of average efficacy were calculated within homogeneous groups. Results :,Quadruple therapy containing a gastric acid inhibitor, bismuth, metronidazole and tetracycline was enhanced when omeprazole was included, treatment duration lasted 10,14 days, and when therapy took place in the Netherlands, Hong Kong and Australia. Treatment efficacy decreased as the prevalence of metronidazole resistance increased. Even in areas with a high prevalence of metronidazole resistance, this quadruple regimen eradicated more than 85% of H. pylori infections when it contained omeprazole and was given for 10,14 days. Furthermore, in the presence of clarithromycin resistance, this quadruple regimen eradicated 90,100% of H. pylori infections, while the currently recommended triple therapy containing clarithromycin, amoxicillin and a proton-pump inhibitor eradicated only 25,61% (P < 0.001). Adherence and adverse events for quadruple therapy were similar to currently recommended triple therapies. Conclusions :,Guidelines should include quadruple therapy with a proton-pump inhibitor, a bismuth compound, metronidazole and tetracycline among recommended first-line anti- H. pylori therapies. [source] | ||||||||||