Notes: Background.In large-scale multi-center clinical trials, the US 13C-urea breath test (UBT) has proven to have a sensitivity and specificity of approximately 95%. Ingestion of a meal to delay gastric emptying has advantages of increasing the level of signal as well as prolonging the duration of significantly increased 13C excretion, at the expense of requiring 40 to 60 minutes to complete the test. Our aim was to explore the utility of the 13C-UBT with a total duration of 30 minutes or less. Methods. After a baseline breath sample was obtained, 125 mg of 13C-urea was given in 100 ml of water, and additional breath samples were taken after 20 and 30 minutes. The results of the UBT were compared to histological assessment, culture, and the rapid urease test. 13C-UBTs were carried out on normal volunteers who underwent gastroscopy during which six mucosal biopsies were taken. Three biopsies were for histological evaluation (Genta stain), two for culture, and one was for agar gel rapid urease testing. The UBT was conducted 2 to 3 days either before or after the endoscopic procedure. Results.The cutoff value for a positive UBT was enrichment of 2.4Δ%0 (delta over baseline). Of the 66 tests, 51%0 were Helicobacter pylori-positive. There were no false positive UBTs and only two false negative UBTs at 20 minutes (sensitivity, 96%; specificity, 100%). At 30 minutes, one other UBT was false negative (gray zone of 2.36%0.) (sensitivity, 94%; specificity, 100%). Conclusion. These results suggest that omission of the meal and shortening the duration of the US 13C-UBT to 20 minutes still may maintain excellent specificity and sensitivity of the test.

Notes: Background.The role of the temperature of the diet as a potential etiological factor for gastritis or peptic ulcer disease has been postulated since the beginning of the century. Animal studies have demonstrated damage to gastric mucosa caused by hot water at 60 to 80°C. In the pre-Helicobacter pylori era it was reported that the majority of ulcer patients preferred hot drinks. It also was reported that the temperature of choice for drinks increased with severity of histological grade of gastritis. We evaluated the association between the preferred temperature of hot drinks and the presence of H. pylori infection. Methods. We tested the temperature of choice for hot drinking liquids among 12 H. pylori-negative and 43 H. pylori-positive volunteers. We also compared the effect of H. pylori therapy on hot drink temperature preference and, in 32 individuals, whether there was a relation between temperature and the degree of gastric atrophy. Results.There was no difference in the preferred temperature for hot drinks between those volunteers with and without H. pylori infection (63.4°± 6°C compared to 61.3°± 7°C, respectively) (mean ± 1 SD, p=.3) There was no change in preferred temperature after successful therapy of the H. pylori infection compared to unsuccessful H. pylori therapy, nor was there a correlation between the preferred temperature and the presence, absence, or degree of gastric atrophy (r2 〈 0.001). Conclusion. The temperature of preference for hot drinks was not influenced by H. pylori infection or by the presence of atrophic gastritis.

Notes: The factors influencing the acquisition and prevalence of Helicobacter pylori infection remain incompletely understood. In Russia, the demographic and socioeconomic factors are relatively similar, allowing investigation of risk factors that might not be identifiable in a more diverse population. Materials and Methods.Sero-prevalence of H. pylori infection was studied in 520 asymptomatic individuals between the ages of 1 and 75 years, residing in St. Petersburg, Russia. Forty-four children lived in orphanages or communal apartments. Demographic information and socioeconomic factors were evaluated, including educational level, income, and living conditions. Helicobacter pylori status was evaluated by using an enzyme-linked immunosorbent assay for anti-H. pylori IgG. Results.The prevalence of H. pylori infection was 44% in children and 88% in adults (P 〈 .001). In adults, H. pylori prevalence was independent of socioeconomic factors. The crude and the age-adjusted odds ratios (ORs) in children showed an inverse correlation between the mother's educational level and H. pylori seropositivity [e.g., OR, 1.8; (95% confidence interval (CI) = 1–3.2] for children whose mothers completed only 8 to 10 years of school compared to children whose mothers completed university. Overcrowding in childhood also was associated with increased H. pylori prevalence. Children from orphanages and communal apartments had the highest crowding index and also were at the greatest risk for H. pylori acquisition (age-adjusted OR, 2.1; 95% CI = 1.2–2.5). Conclusions.The prevalence of H. pylori infection in Russia correlated with socioeconomic factors, suggesting there are differences sufficient to affect H. pylori transmission. The prevalence of H. pylori infection during childhood forms the basis for the variances in prevalence among populations.

Notes: BackgroundIsolating Helicobacter pylori on culture media and performing antibiotic susceptibility testing is potentially the most useful tool for guiding antibiotic therapy, especially when antimicrobial resistance is suspected. The aim of this study was to determine whether the yield of H. pylori culture was related to the site from which the gastric specimen was obtained either before or after therapy. Methods.Gastric mucosal biopsies from the antrum and the corpus of the stomach were cultured. H. pylori status was determined by histological assessment using the Genta stain. Results.Fifty-two patients with documented H. pylori infection were studied: Twenty-three were tested before antibiotic therapy and 29 after therapy had failed. In 47 patients (90%), both antral and corpus culture specimens were positive. In 5 patients (10%), only one site was positive, with three false-negative antral and two false negative corpus cultures. The overall sensitivity of culture in detecting H. pylori infection was 95% (95% confidence interval = 89–98%) and was not significantly different for the antrum or corpus, either before or after therapy. Conclusion.Culture of gastric biopsies from either the antrum or the corpus has an excellent diagnostic yield even in patients who failed antimicrobial therapy.

Notes: Background Helicobacter pylori infection presents as many different diseases, including asymptomatic gastritis, peptic ulcer disease, and gastric cancer. Although the virulence factor(s) responsible for different H. pylori-related diseases have not been identified, several candidate genes are being investigated for such an association. The polymerase chain reaction (PCR) frequently is used to assess the presence of genetic factors associated with pathogenesis of disease; the cagA gene and its product have been postulated to have a disease-specific relationship to peptic ulcer and gastric cancer because of differential expression in these diseases compared to histological gastritis alone. Materials and Methods.Genomic DNA was amplified by PCR, using synthetic oligonucleotide primers to the cagA gene to determine the prevalence of the cagA gene in 60 H. pylori isolates obtained from well-documented duodenal ulcer or asymptomatic gastritis patients (30 each). Results were confirmed by hybridization with a 1.4-Kb cagA probe. Results.The expected PCR product was obtained in 90% of isolates from duodenal ulcer patients, compared to 70% of isolates from individuals with asymptomatic gastritis. The PCR products were polymorphic in size, suggesting cagA gene sequence differences among isolates. Evaluation for the presence of the cagA gene by hybridization with a 1.4-Kb cagA probe showed a homologous product in 29 of 30 strains [96.7%; 95% confidence interval (CI) = 83–100%] from duodenal ulcer patients versus 25 of 30 strains (83.3%; 95% CI = 65–94%) obtained from individuals with asymptomatic gastritis (p= 0.19). Conclusions.The high prevalence of the cagA gene in asymptomatic gastritis suggests that it will not prove to be a useful marker to distinguish more virulent or disease-specific H. pylori strains. The genetic heterogeneity among H. pylori strains makes PCR an unwise choice as the single method to determine prevalence of a putative virulence factor. In evaluation of the prevalence of a gene or genetic factor in a population of H. pylori, hybridization with extended probes might be important to ensure that the results are representative of the organism's genotype.

Notes: Background.The current study was designed to evaluate the effect of aging and Helicobacter pylori infection on the gastric mucosa in asymptomatic Japanese adults. Materials and Methods.Eighty-five asymptomatic healthy adults were recruited from a health-screening center in Sapporo. All subjects underwent endoscopy and gastric biopsy, and serum was obtained for IgG antibodies to H. pylori, serum gastrin, and pepsinogen levels. Results.The prevalence of atrophic change of the gastric mucosa assessed by pathological findings increased with age (49% in the 30- to 39-year-old group compared to 89% in those 60 years and older, p 〈 .001). The frequency of intestinal metaplasia also increased with age (38% in the 30- to 39-year-old group compared to 82% in those 60 years and older, p 〈 .001). In contrast, the frequency of atrophic gastritis and intestinal metaplasia was extremely low in the H. pylori seronegative group regardless of age. Mean serum gastrin level in H. pylori-positive adults was significantly greater than in those who were H. pylori-negative (114.3 ± 11.2 compared to 65.8 ± 6.5 pg/ml, p 〈 .03). The serum pepsinogen I-II ratio was significantly lower in those with H. pylori infection than in those without (3.1 compared to 6.6, p 〈 .0001). Conclusions.These results suggest that the chronological changes in the gastric mucosa in Japanese individuals are either entirely related to H. pylori infection or the process is greatly accelerated by H. pylori infection.

Notes: BackgroundRapid urease tests (RUTs) provide a simple, sensitive method of detecting Helicobacter pylori infection. Objectives.Our aim, therefore, was to determine whether the yield of detecting H. pylori infection by RUT varied depending on the site of gastric biopsy. Materials and Methods.Gastric biopsies were obtained from 50 patients for RUT by use of hpfast (GI Supply, Camp Hill, PA). Biopsies were taken from the prepyloric greater curve antrum, from the gastric angle, and from the greater curve in mid-corpus. One biopsy specimen was placed in the RUT gel, and the biopsy from the adjacent mucosa was placed in formalin for subsequent histological evaluation by using the Genta stain. RUTs were examined and scored at intervals of 5, 10, 15, 30, and 45 minutes and after 1, 2, 4, and 24 hours. Results.Fifty patients were entered in the test (150 RUTs), 32 having H. pylori infection. There were no false-positive RUTs (specificity, 100%). The gastric angle site was positive in 100%. The prepyloric site was positive in 87%, and the corpus site was positive in 84.4% (p 〈 .052 for angle or prepyloric antrum versus corpus). The most common pattern was for all to be positive (74%). The median time to positivity was similar with angle and prepyloric sites (37.5 and 60 minutes, respectively, p= not significant) and shorter than the corpus biopsy (180 minutes); (p 〈 .05 for angle or prepyloric antrum versus corpus). Conclusion.The maximum probability for detecting H. pylori infection using a RUT is to obtain a biopsy from the gastric angle. To prevent missing a positive result when intestinal metaplasia is present, we recommend that (at a minimum) biopsies be taken from both the angle and the corpus.

Notes: Background.Treatment of antibiotic-resistant Helicobacter pylori should be based on bacterial sensitivity testing that requires the ability to isolate the bacterium from gastric mucosal biopsies. The aim of this study was to determine whether the yield for detecting H. pylori infection by culture is reduced by immersion of biopsy forceps in formalin prior to obtaining the specimen. Materials and Methods.Gastric antral mucosal biopsies (100 specimens) from 50 patients were obtained for culture of H. pylori. An antral biopsy was taken for culture, and with the same forceps a biopsy was taken for histological examination. The biopsy specimen was removed by shaking, whereas the forceps was immersed in 10% buffered formalin for the histological investigation. The forceps was then used without rinsing to obtain a second specimen for culture from an area adjacent to the first site. H. pylori status was determined by histological assessment with the Genta stain and a rapid urease test. Results.Fifty patients with H. pylori infection documented by histological inquiry and positive rapid urease testing entered the study; 29 had duodenal ulcers, 5 had gastric ulcers, 1 had mucosal associated lymphoid tissue (MALT) lymphoma, and 15 were without ulcer disease. The results of culture both before and after immersion in formalin were identical. One patient had both cultures negative; the sensitivity of culture for detection of H. pylori infection was 98% (95% confidence interval =93%-100%). Conclusion. Preimmersion of biopsy forceps in formalin does not adversely affect the ability to culture H. pylori.

Notes: Mosaicism in vacA alleles with three distinct families of vacA signal sequences (s1a, s1b and s2) and two distinct families of middle region alleles (m1 and m2) has been reported. It was suggested that the vacA s1a genotype was closely associated with duodenal ulcer disease and with high cytotoxin production. The aim of this study was to evaluate the role of vacA genotyping with respect to gastric inflammation and injury, cytotoxin activity, and clinical presentation.〈section xml:id="abs1-2"〉〈title type="main"〉Methods. H. pylori from patients with gastritis, peptic ulcer disease, or gastric cancer were characterized by vacA typing by polymerase chain reaction (PCR) and DNA sequencing. In vitro cytotoxin activity was assessed by vacuolation assay using Vero cells as well as with Hela cells.〈section xml:id="abs1-3"〉〈title type="main"〉Results.Four hundred ninety-one strains were tested. vacA genotype s1a/m1 was present in more than 95% of strains independent of presentation with gastritis, peptic ulcer, or gastric cancer. No vacA genotype was associated with high average cytotoxin activity. The s2/m2 isolates had low or absent cytotoxin activity. All cagA negative strains (n = 18) were s1a strains and both s2/m2 strains were cagA positive. One strain that was a recombinant of m1 and m2 strains was identified and had low cytotoxin activity. The nucleotide and amino acid sequences between original m1 strains and Japanese m1 strains (new m1 strains) were about 85% and 81%, respectively. Strains with the new m1 genotype had nucleotide and amino acid sequences similarity of more than 96%. There was no difference in cytotoxin activity between strains with the Western type m1 and the new type m1 genotype.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusion.In this as in other reported studies (≈ 1500 patients overall) vacA genotype was strongly but not exclusively associated with the presence of cagA. Overall, the studies did not support a role for vacA genotyping in relation to cytotoxin activity, virulence, histologic finding, or risk of a particular H. pylori disease. vacA genotype s1 is likely to be a surrogate marker for the presence of the cag pathogenicity island.