Active Helicobacter pylori (H. pylori) infection may contribute to the ulceration and hemorrhage of otherwise benign gastric lipomas. This case highlights the utility of combining invasive and non-invasive testing of H. pylori in bleeding gastric ulcers and emphasizes the critical role of H. pylori testing and eradication in bleeding gastric lipomas.

The presence of Helicobacter pylori (H. pylori) infection can influence gastric acid production. While both gastroesophageal reflux disease (GERD) and H. pylori are highly prevalent in the Saudi Arabian population, the relationship between these two conditions remains uncertain. This study aims to assess the association between GERD and H. pylori.

This was a cross-sectional study which included patients who underwent endoscopy with gastric biopsy to test for H. pylori. H. pylori status was assessed using histopathology. The GERD-Q questionnaire was used to ascertain the presence of GERD. Multivariate analysis was used to assess the relationship between H. pylori and GERD.

A total of 352 participants were included, with a mean age of 45 years (±14.7) and 58% of them being female. 148 participants (42%) tested positive for H. pylori. 59 (39.9%) had GERD. GERD was identified in 39.9% of the H. pylori-positive group and 37.3% of the H. pylori-negative group. H. pylori was not significantly associated with GERD in the multivariate analysis (P = 0.726, OR = 1.089, 95% CI: 0.675 - 1.759).

There was no association between H. pylori infection and GERD in this Saudi Arabian population.

Helicobacter pylori (H. pylori) infection has been well-established as a significant risk factor for several gastrointestinal disorders. The urea breath test (UBT) has emerged as a leading non-invasive method for detecting H. pylori. Despite numerous studies confirming its substantial accuracy, the reliability of UBT results is often compromised by inherent limitations. These findings underscore the need for a rigorous statistical synthesis to clarify and reconcile the diagnostic accuracy of the UBT for the diagnosis of H. pylori infection.

To determine and compare the diagnostic accuracy of 13C-UBT and 14C-UBT for H. pylori infection in adult patients with dyspepsia.

We conducted an independent search of the PubMed/MEDLINE, EMBASE, and Cochrane Central databases until April 2022. Our search included diagnostic accuracy studies that evaluated at least one of the index tests (13C-UBT or 14C-UBT) against a reference standard. We used the QUADAS-2 tool to assess the methodological quality of the studies. We utilized the bivariate random-effects model to calculate sensitivity, specificity, positive and negative test likelihood ratios (LR+ and LR-), as well as the diagnostic odds ratio (DOR), and their 95% confidence intervals. We conducted subgroup analyses based on urea dosing, time after urea administration, and assessment technique. To investigate a possible threshold effect, we conducted Spearman correlation analysis, and we generated summary receiver operating characteristic (SROC) curves to assess heterogeneity. Finally, we visually inspected a funnel plot and used Egger's test to evaluate publication bias.

The titles and abstracts of 4621 studies were screened; 79 articles were retrieved and selected for full-text reading. Finally, 60 studies were included in the diagnostic test accuracy meta-analysis. Our analysis demonstrates superior diagnostic accuracy of 13C-UBT over 14C-UBT, indicated by higher sensitivity (96.60% vs 96.15%), specificity (96.93% vs 89.84%), likelihood ratios (LR+ 22.00 vs 10.10; LR- 0.05 vs 0.06), and area under the curve (AUC; 0.979 vs 0.968). Notably, 13C-UBT's DOR (586.47) significantly outperforms 14C-UBT (DOR 226.50), making it the preferred diagnostic tool for dyspeptic individuals with H. pylori infection. Correlation analysis revealed no threshold effect (13C-UBT: r = 0.48; 14C-UBT: r = -0.01), and SROC curves showed consistent accuracy. Both 13C-UBT and 14C-UBT showed high AUC values (13C-UBT 0.979; 14C-UBT 0.968) near 1.00, reinforcing their excellent accuracy and endorsing both as reliable diagnostic tools in clinical practice.

In summary, our study has demonstrated that 13C-UBT has been found to outperform the 14C-UBT, making it the preferred diagnostic approach. Additionally, our results emphasize the significance of carefully considering urea dosage, assessment timing, and measurement techniques for both tests to enhance diagnostic precision. Nevertheless, it is crucial for researchers and clinicians to evaluate the strengths and limitations of our findings before implementing them in practice.

Helicobacter pylori (H. pylori) is endemic in Africa with a prevalence estimate of 79.1%. In addition, there is a significant community burden of dyspepsia in Africa, similar to other western countries. However, the majority of infected persons do not manifest the disease. In Africa, for instance, peptic ulcer disease is prevalent, whereas gastric cancer has reportedly low incidence. Therefore, it is important that testing is focused, targeting individuals most likely to benefit from treatment. In Africa, there are currently no guidelines for H. pylori testing and treatment. Empirical treatment is common due to variable access to diagnostics and health care. To assess the spectrum of H. pylori testing in Africa, we performed a literature search in PubMed over the past 10 years, 2013 to 2023. Histology was the most widely used modality in 16 out of 18 countries. Capacity for culture was shown in 11 studies, importantly across regions of Africa. H. pylori serology was demonstrated in 8 countries, although it has limited sensitivity in identifying active infection. H. pylori test-and-treat strategy has been shown to be cost-effective. Particularly in a region with high antibiotic resistance, adopting this strategy ensures that only confirmed positive patients are treated. Furthermore, test-of-cure ought to be mandatory to guide future therapies. Health authorities can leverage polymerase chain reaction facilities, left behind by the coronavirus disease 2019 pandemic, to make molecular susceptibility testing available in the near future. A systematic approach to testing incorporating indication for endoscopy and medication use is recommended.

The aim of this study was to investigate whether elevated blood lead level (BLL) is a risk factor for Helicobacter pylori infection. Upper gastrointestinal endoscopy was performed on 2,625 subjects who visited a university hospital for general health examination. H. pylori infection was detected using histologic examination with Giemsa staining, and BLLs were measured. The mean BLL was 2.83 ± 1.31 μg/dL. The prevalence of H. pylori infection was 27.8%. The BLL was significantly higher in the H. pylori infection-positive group compared to the non-infected group (2.96 ± 1.33 μg/dL vs. 2.78 ± 1.30 μg/dL, p < 0.001), which remained significant after adjusting for other confounders. H. pylori infection significantly increased as the BLL increased (OR: 1.143, 95% CI 1.068-1.223). We found a relationship between BLL elevation and H. pylori infection rate.

Helicobacter pylori (H pylori) infection has been implicated in a number of malignancies and non-malignant conditions including peptic ulcers, non-ulcer dyspepsia, recurrent peptic ulcer bleeding, unexplained iron deficiency anaemia, idiopathic thrombocytopaenia purpura, and colorectal adenomas. The confirmatory diagnosis of H pylori is by endoscopic biopsy, followed by histopathological examination using haemotoxylin and eosin (H & E) stain or special stains such as Giemsa stain and Warthin-Starry stain. Special stains are more accurate than H & E stain. There is significant uncertainty about the diagnostic accuracy of non-invasive tests for diagnosis of H pylori.

To compare the diagnostic accuracy of urea breath test, serology, and stool antigen test, used alone or in combination, for diagnosis of H pylori infection in symptomatic and asymptomatic people, so that eradication therapy for H pylori can be started.

We searched MEDLINE, Embase, the Science Citation Index and the National Institute for Health Research Health Technology Assessment Database on 4 March 2016. We screened references in the included studies to identify additional studies. We also conducted citation searches of relevant studies, most recently on 4 December 2016. We did not restrict studies by language or publication status, or whether data were collected prospectively or retrospectively.

We included diagnostic accuracy studies that evaluated at least one of the index tests (urea breath test using isotopes such as 13C or 14C, serology and stool antigen test) against the reference standard (histopathological examination using H & E stain, special stains or immunohistochemical stain) in people suspected of having H pylori infection.

Two review authors independently screened the references to identify relevant studies and independently extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We performed meta-analysis by using the hierarchical summary receiver operating characteristic (HSROC) model to estimate and compare SROC curves. Where appropriate, we used bivariate or univariate logistic regression models to estimate summary sensitivities and specificities.

We included 101 studies involving 11,003 participants, of which 5839 participants (53.1%) had H pylori infection. The prevalence of H pylori infection in the studies ranged from 15.2% to 94.7%, with a median prevalence of 53.7% (interquartile range 42.0% to 66.5%). Most of the studies (57%) included participants with dyspepsia and 53 studies excluded participants who recently had proton pump inhibitors or antibiotics.There was at least an unclear risk of bias or unclear applicability concern for each study.Of the 101 studies, 15 compared the accuracy of two index tests and two studies compared the accuracy of three index tests. Thirty-four studies (4242 participants) evaluated serology; 29 studies (2988 participants) evaluated stool antigen test; 34 studies (3139 participants) evaluated urea breath test-13C; 21 studies (1810 participants) evaluated urea breath test-14C; and two studies (127 participants) evaluated urea breath test but did not report the isotope used. The thresholds used to define test positivity and the staining techniques used for histopathological examination (reference standard) varied between studies. Due to sparse data for each threshold reported, it was not possible to identify the best threshold for each test.Using data from 99 studies in an indirect test comparison, there was statistical evidence of a difference in diagnostic accuracy between urea breath test-13C, urea breath test-14C, serology and stool antigen test (P = 0.024). The diagnostic odds ratios for urea breath test-13C, urea breath test-14C, serology, and stool antigen test were 153 (95% confidence interval (CI) 73.7 to 316), 105 (95% CI 74.0 to 150), 47.4 (95% CI 25.5 to 88.1) and 45.1 (95% CI 24.2 to 84.1). The sensitivity (95% CI) estimated at a fixed specificity of 0.90 (median from studies across the four tests), was 0.94 (95% CI 0.89 to 0.97) for urea breath test-13C, 0.92 (95% CI 0.89 to 0.94) for urea breath test-14C, 0.84 (95% CI 0.74 to 0.91) for serology, and 0.83 (95% CI 0.73 to 0.90) for stool antigen test. This implies that on average, given a specificity of 0.90 and prevalence of 53.7% (median specificity and prevalence in the studies), out of 1000 people tested for H pylori infection, there will be 46 false positives (people without H pylori infection who will be diagnosed as having H pylori infection). In this hypothetical cohort, urea breath test-13C, urea breath test-14C, serology, and stool antigen test will give 30 (95% CI 15 to 58), 42 (95% CI 30 to 58), 86 (95% CI 50 to 140), and 89 (95% CI 52 to 146) false negatives respectively (people with H pylori infection for whom the diagnosis of H pylori will be missed).Direct comparisons were based on few head-to-head studies. The ratios of diagnostic odds ratios (DORs) were 0.68 (95% CI 0.12 to 3.70; P = 0.56) for urea breath test-13C versus serology (seven studies), and 0.88 (95% CI 0.14 to 5.56; P = 0.84) for urea breath test-13C versus stool antigen test (seven studies). The 95% CIs of these estimates overlap with those of the ratios of DORs from the indirect comparison. Data were limited or unavailable for meta-analysis of other direct comparisons.

In people without a history of gastrectomy and those who have not recently had antibiotics or proton ,pump inhibitors, urea breath tests had high diagnostic accuracy while serology and stool antigen tests were less accurate for diagnosis of Helicobacter pylori infection.This is based on an indirect test comparison (with potential for bias due to confounding), as evidence from direct comparisons was limited or unavailable. The thresholds used for these tests were highly variable and we were unable to identify specific thresholds that might be useful in clinical practice.We need further comparative studies of high methodological quality to obtain more reliable evidence of relative accuracy between the tests. Such studies should be conducted prospectively in a representative spectrum of participants and clearly reported to ensure low risk of bias. Most importantly, studies should prespecify and clearly report thresholds used, and should avoid inappropriate exclusions.

Development of an accurate and less cumbersome noninvasive method to detect current Helicobacter pylori infection is essential in clinic. The aim of this study was to evaluate the performance of the CIM test, also known as the Assure H. pylori Rapid Test (Genelabs Diagnostics Pty. Ltd., Singapore), for the diagnosis of current H. pylori infection before and after eradication therapy in Chinese population.

A total of 452 eligible people were recruited for this study in Jiangsu Province, China. Each individual underwent a 13C urea breath test (13C-UBT). For the evaluation of CIM test after eradication, 115 H. pylori-positive outpatients were treated with 1-week triple therapy. One month after the end of therapy, the patients underwent 13C-UBT again, and the CIM-test was performed 1, 3, and 6 months after the end of therapy. Its performance (sensitivity, specificity, positive and negative predictive values, and accuracy) were determined using the 13C-UBT as a gold standard for H. pylori diagnosis.

H. pylori was detected in 221 (65.6%) of the 337 people by 13C-UBT. The sensitivity, specificity, positive and negative predictive values, and accuracy of the CIM test were 93.2%, 90.5%, 94.9%, 87.5%, and 92.3%, respectively, using 13C-UBT as a gold standard. One month after eradication therapy, the sensitivity, specificity of CIM test were only 50% and 66.7%, 66.7% and 84.6% 3-month after eradication therapy and the sensitivity, specificity increased to 85.7% and 96.9%, respectively, when CIM test was used 6 months after the end of anti-H. pylori therapy.

The CIM test is a simple, rapid, accurate, cheap, and near-people test. It may be satisfactory for detecting H. pylori infection in cases without eradication therapy, but it could not differentiate the past or current infection correctly within 6 months after anti-H. pylori therapy.

To develop a 13C-urea-containing capsule for more economic and sensitive diagnosis of Helicobacter pylori infection, the 13C-urea-containing capsules were prepared with various additives such as polyethylene glycol, microcrystalline cellulose, sodium lauryl sulfate and citric acid. Their dissolution test and 13C-urea Breath Test in human volunteers were then performed. Polyethylene glycol increased the initial dissolution rates of urea and difference delta 13C values from 13C-urea, while microcrystalline cellulose and sodium lauryl sulfate decreased them. Irrespective of addition of citric acid, the compositions with polyethylene glycol showed higher values from 13C-urea compared to a commercial 76 mg 13C-urea-containing capsule due to higher initial dissolution rate. The capsules with 38 mg 13C-urea and 1.9 mg polyethylene glycol, which showed higher Helicobacter pylori-positive value of about 8 per thousand at 10 min, improved the sensitivity of 13C-urea in human volunteers. Thus, the 13C-urea-containing capsule with polyethylene glycol would be a more economical and sensitive preparation for diagnosis of Helicobacter pylori infection.

To validate and compare the cost of microdose 14C urea breath test (UBT) with histology and rapid urease test for the diagnosis of H Pylori.

Ninety-four consecutive patients with dyspeptic symptoms undergoing gastroscopy were enrolled. Gastric biopsies were taken for histology and rapid urease test. UBT was performed after gastroscopy by microdose 14C urea capsules. Sensitivity, specificity and accuracy of UBT were calculated and compared with histology and rapid urease test. Cost comparison of these tests was also performed.

H pylori was diagnosed by histology and rapid urease test in 66 (70%) and 61 (65%) patients, while 14C UBT detected infection in 63 (67%). Accuracy of UBT was 93% in comparison with histology while its positive and negative predictive values were 97% and 84%, respectively. Comparison of 14C UBT with rapid urease test gives an accuracy of 96%, with positive and negative predictive values of 95% and 97%, respectively. These results were highly reproducible with a Kappa test (P value<0.001). Cost of histology or rapid urease test with gastroscopy was 110 USD or 95 USD respectively while the cost of UBT was 15 USD.

Microdose 14C UBT was comparable to histology and rapid urease test. 14C UBT is an economical, self sufficient and suitable test to diagnose active H pylori infection in less developed countries.

Data regarding the prevalence of Helicobacter pylori infection and its potential risk factors among schoolchildren from the Middle East is scarce.

An enzyme-linked immunosorbent assay was used to investigate H. pylori status in four groups of children: The first and second groups, 50 children each (25 boys, 25 girls) included children from high socioeconomic class (group 1 = 6 years old; group 2 = 9 years old). The third and fourth groups were sex- and age-matched, but from low socioeconomic class. To evaluate the association between the seroprevalence of H. pylori and selected risk factors, odds ratios (crude and adjusted) were calculated using multiple regression analysis.

Overall seroprevalence rate was 55.5%. Seropositivity was 42%, 52%, 60%, and 68% for groups 1, 2, 3, and 4, respectively. Age and sex were not significantly associated with H. pylori seropositivity. In the final logistic regression model, which was adjusted for age and sex, the following risk factors were found to be significantly associated with seropositivity: living in rural areas (P = 0.015), poor sanitation (P < 0.001), overcrowding (P = 0.014), low maternal educational level (P = 0.010) and low socioeconomic status (P = 0.011).

The prevalence of H. pylori infection in Jordanian schoolchildren is high, suggesting that most acquisition occurs before the age of 6 years. The seroprevalence for H. pylori increases with social deprivation.

Helicobacter pylori infection in chronic renal failure patients has been linked to peptic ulcer and gastric neoplasia after kidney transplantation. It may also contribute to the accelerated arteriosclerosis that is usual in this population. Few data are available on the usefulness of noninvasive diagnostic tests for H. pylori infection in dialyzed patients, especially regarding the new fecal antigen detection tests. The objective of this study was to determine the efficacy of a noninvasive test for H. pylori infection in patients with chronic renal failure.

Eighty-six patients were included in a cross-sectional study. Urea breath test, serology and three fecal tests--FemtoLab H. pylori (Connex, Germany), Premier Platinum HpSA (Meridian, USA) and Simple H. pylori (Operon SA, Spain) were performed. Helicobacter pylori status was determined by concordance of the tests. Sensitivity, specificity and positive and negative predictive values were calculated for each test.

Sensitivity, specificity, positive and negative predictive values were 94%, 96%, 94% and 96% for the urea breath test; 97%, 64%, 66% and 97% for serology; 86%, 100%, 100% and 91%, for FemtoLab H. pylori; 58%, 96%, 91% and 76% for Premier Platinum HpSA and 61%, 78%, 74% and 67% for Simple H. pylori.

The urea breath test seems to be the most reliable diagnostic method for H. pylori infection in patients with chronic renal failure. Serology has a low specificity, and the results of the fecal tests vary widely.

Dyspepsia is a common symptom. Dyspeptic symptoms may be caused by a variety of conditions such as peptic ulcer disease, gastro-oesophageal reflux, and malignancy. Most often, however, no cause is identified and dyspepsia is deemed to be functional. While symptom severity does influence frequency of consultation, dyspeptic consulters also differ from non-consulters with respect to symptom perception and anxiety. This highlights the importance of understanding the patient's agenda early in the course of evaluation. Patients over the age of 55 years or with alarm symptoms should be referred for prompt endoscopy. In the absence of other clinically apparent aetiologies, uninvestigated dyspeptics can be either tested and treated for Helicobacter pylori or empirically treated with proton pump inhibitors. Uninvestigated dyspeptics failing empiric therapy should be referred for evaluation that includes endoscopy. Further therapy with prokinetics, tricyclic antidepressants, fundal relaxants, antidepressants, or psychotherapy is guided by predominant symptoms and assessment of possible psychiatric factors.

The purpose of this study was to characterize the radiographic findings of antral gastritis and to determine whether there are differences in the appearance of antral gastritis in patients with and without Helicobacter pylori infection. A search of radiology, endoscopy and pathology files revealed 90 patients with antral gastritis on double contrast upper gastrointestinal tract studies who had endoscopy with testing for H. pylori. The barium studies were evaluated to further characterize the findings of antral gastritis without knowledge of the H. pylori status of the patients or of the endoscopy or pathology findings. The radiographic findings of antral gastritis included thickened folds in 67 patients (74%), polypoid antral gastritis (a subset of patients with thickened folds) in 6 (9%), antral erosions in 21 (23%), enlarged areae gastricae in 14 (16%), crenulation of the lesser curvature in 4 (4%), mucosal nodularity in 2 (2%), a hypertrophied antral-pyloric fold in 2 (2%) and antral striae in 1 (1%). 43 patients (48%) with antral gastritis were H. pylori positive and 47 patients (52%) were H. pylori negative. Thickened folds were detected in 39 H. pylori-positive patients (91%) with antral gastritis vs 28 H. pylori-negative patients (60%) (p<0.001); polypoid gastritis in 6 H. pylori-positive patients (14%) vs 0 H. pylori-negative patients (p<0.05); enlarged areae gastricae in 14 H. pylori-positive patients (33%) vs 0 H. pylori-negative patients (p<0.0001); and antral erosions in 2 H. pylori-positive patients (5%) vs 19 H. pylori-negative patients (40%) (p<0.0001). Our experience suggests that antral gastritis caused by H. pylori infection is associated with characteristic features on double contrast studies (including thickened folds, polypoid gastritis and enlarged areae gastricae) and that this condition is rarely associated with antral erosions. Thus, radiologists can often suggest whether the patient's gastritis is caused by H. pylori on the basis of radiographic findings.

PCR is a rapid, sensitive and accurate method for the specific detection of Helicobacter pylori from gastric biopsy specimens. In our study, 104 gastric tissue specimens from symptomatic adult patients were examined by staining, culture, PCR and nested PCR methods for detection of H. pylori. According to our results, positivity was achieved in 24% (25/104) with Giemsa staining, 34% (36/104) with histopathology, 36% (38/104) with PCR and 41% (43/104) with nested PCR respectively, whereas H. pylori was isolated in only 33% (35/104) of the cultures on the biopsy specimens. Both the sensitivity and the positive predictive value of the nested PCR method were 100%, and both the specificity and negative predictive value were 98%. As a conclusion, our results suggest the nested PCR as a highly valuable method in the detection of H. pylori with a reasonably high sensitivity and specificity.

There are two general ways in which a diagnosis of infection by Helicobacter pylori can be made: by using either an invasive or non-invasive procedure. The invasive procedures involve an endoscopy and biopsy. A biopsy is essential because often the mucosa may appear macroscopically normal but nevertheless be inflamed. A biopsy is obtained by histological examination, culture, polymerase chain reaction or detection of the presence of urease activity in biopsy material. The non-invasive tests that can be used to diagnose the infection are serology, detection of labelled metabolic products of urea hydrolysis in the breath (13CO2, 14CO2), the urine or the blood, and detection of H, pylori antigen in a stool specimen. At present no single test can be relied upon to detect definitely colonization by H. pylori, and a combination of two is recommended if this is feasible. The choice of the test to be used is not straightforward and may vary according to the clinical condition and local expertise.

To study the accuracy of four currently used tests for the diagnostic of Helicobacter pylori infection among gastric ulcer patients with a gold standard as reference which combines several diagnostic methods.

Seventy-three consecutive gastric ulcer patients were prospectively studied. From all patients, three biopsies each were obtained from both antrum and body (two for haematoxylin-eosin staining and one for rapid urease test--Jatrox H.p. Test--. Also, IgG ELISA serology (Helico G) and 13C-urea breath test were performed. According to the gold standard, a patient was considered to be infected with H. pylori when at least two tests were positive; a patient was considered not to be infected with H. pylori when at least three tests were negative.

Among gastric ulcer patients, the prevalence of H. pylori infection was 87.6% (95% CI: 78%-93%) with the gold standard as reference. The sensitivity and specificity values were as follows: histology (antrum), 96.8% (89%-99%) and 100% (66%-100%), respectively; histology (body), 98.4% (91%-100%) and 100% (66%-100%); urease test (antrum), 71.8% (60%-81%) and 100% (66%-100%); urease test (body), 96.8% (89%-99%) and 100% (66%-100%); breath test, 100% (94%-100%) and 100% (66%-100%), and serology, 95.3% (87%-98%) and 100% (66%-100%). The sensitivity of the urease test was higher with a body biopsy specimen (McNemar: 15; p < 0.001).

All diagnostic tests (histology, rapid urease test, 13C-urea breath test and serology) are highly accurate for the diagnosis of H. pylori infection among gastric ulcer patients with the exception of the rapid urease test performed with antrum biopsy specimens, where this test displays a lower sensitivity for bacterial detection.

Rapid urease tests for Helicobacter pylori have a sensitivity of 80% to 90%. Therefore histologic examination of gastric biopsies is recommended as a "backup" diagnostic test in rapid urease test-negative patients. However, noninvasive tests (urea breath test, serology, whole blood antibody tests) may provide a more rapid diagnosis and be less expensive but offer similar accuracy.

Sixty-seven patients (no prior treatment for H pylori, no proton pump inhibitors, antibiotics, or bismuth within 4 weeks) undergoing endoscopy for evaluation of dyspepsia symptoms and testing rapid urease test-negative by antral biopsy were enrolled. All had the following tests: gastric biopsies (2 antral, 1 fundus; H&E and Alcian Yellow stain) examined for gastritis and H pylori; (13)C-UBT; capillary blood for whole blood rapid antibody tests: FlexSure HP, QuickVue, AccuStat, and Stat-Simple Pylori; serum for FlexSure HP; HM-CAP enzyme-linked immunoassay. H pylori infection was diagnosed (reference standard) if chronic gastritis was present on histology and at least 2 of the 3 following tests were positive: urea breath test, H pylori organisms unequivocally demonstrated in biopsies on special stain, and/or enzyme-linked immunoassay. The test and treatment costs per patient were calculated.

Of 67 patients with a negative rapid urease test, 4 were positive for H pylori. None had active peptic ulcer disease. Histology only identified 1 patient with organisms visible on special stain. Using chronic active gastritis (neutrophilic and mononuclear infiltrate) as a diagnostic criterion for H pylori, 6 patients would have been judged positive. However, only 2 of these were truly positive by the reference standard (positive predictive value 33%). Negative predictive value for presence of organisms and chronic active gastritis was 95% and 97%, respectively. All of the noninvasive tests identified all 4 truly positive patients correctly. Urea breath test and FlexSure whole blood assay yielded a substantial number of false-positive results (positive predictive value 31% and 36%, respectively); positive predictive value for the other tests ranged from 50% to 80%. All tests except histology had a negative predictive value of 100%. Histology was the most costly test (p < 0. 001 compared with all other tests), followed by urea breath test and HM-CAP serology (p < 0.001 compared with all rapid antibody tests).

Whole blood or serum antibody testing is a rapid, accurate, and cost-effective means for establishing H pylori status in rapid urease test-negative patients. Whole blood or serology rapid antibody testing should substitute for histology when the patient has not been previously treated for H pylori.

Several noninvasive methods are now available for diagnosing Helicobacter pylori infection. Because the prevalence of H. pylori infection is variable in patients requiring testing, the optimal testing strategies may vary under different conditions. The aim of this study was to evaluate the cost-effectiveness of competing diagnostic strategies for H. pylori in patients with varying H. pylori prevalence.

A decision analysis was performed comparing the costs per number of correct diagnoses achieved by alternative sequential testing strategies. Estimates of H. pylori prevalence and test characteristics were derived from a systematic review of the MEDLINE bibliographic database. Cost estimates were derived from the 2000 Medicare Fee Schedule.

The enzyme-linked immunosorbent assay (ELISA) test had the lowest cost per correct diagnosis at low (30%), intermediate (60%), and high (90%) prevalence ($90-$95/correct diagnosis), but its diagnostic accuracy was low (80-84%). At low and intermediate prevalence the stool test was more accurate (93%), with an average cost of $126-$127 per correct diagnosis. Additional confirmatory testing of positive or negative tests increased the diagnostic accuracy of the stool test, but had high incremental costs. ELISA testing was preferable when prevalence rates were very high (90%), and using a confirmatory urea breath test for negative ELISA tests increased the diagnostic accuracy to 96%, with modest incremental costs. If the cost of the breath test was <$50 or if the cost of the stool test is >$82, breath testing became preferable to stool testing. If the cost of the stool test fell to <$20, it became preferable to ELISA. Similarly, if the cost of the ELISA serology was >$39 then stool testing became preferable at all prevalence rates. Fingerstick whole blood tests were not cost-effective.

The choice of an initial test for H. pylori detection depends on the prevalence of H. pylori infection and the value placed on increased diagnostic accuracy. Although ELISA results in the lowest cost-effectiveness ratios, in patients at low-intermediate pretest probability of infection, the stool test provides increased accuracy, with modest incremental costs.

Near patient tests for Helicobacter pylori were developed to assist in the management of dyspepsia patients in general practice. Most studies were performed in western populations.

To evaluate the rapid whole blood test (Flexpack HP) for H. pylori in the Chinese population.

Consecutive dyspeptic patients referred for upper endoscopy were recruited. During upper endoscopy, biopsies were taken from the antrum and corpus for rapid urease test (CLO test) and histological examination. After endoscopy, the whole blood test (FlexPack HP) was performed according to the manufacturer's instruction. Patients then received a 13C-urea breath test. Results of the whole blood test were compared with the gold standard (CLO test, histology and 13C-urea breath test).

A total of 294 consecutive patients gave a valid Flexpack HP result for interpretation. The mean age of patients was 47.7 (range 15-85) years. Analysis showed a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 58%, 92%, 91%, 63% and 73% respectively.

The FlexPack HP whole blood test showed good specificity but lacked sensitivity. It is not sensitive enough to be used in a general practice setting for the test-and-treat approach in the Chinese population.

This study was conducted to determine the optimal cut-off value and breath sample collection time for the [13C]-urea breath test based on the assessment of Helicobacter pylori status with a gastric juice-based polymerase chain reaction (PCR) assay.

A total of 104 patients took 100 mg [13C]-urea orally and breath samples were collected at 5, 10, 20, 30 and 60 min. The increment of 13CO2:12CO, ratio from the baseline (delta13C) was measured using a laser spectroanalyser. The PCR assay was positive in 63 and negative in 41 patients. The optimal cut-off value of delta13C was calculated for each sample collection time so that the distance from the geometric mean value among Helicobacter pylori-positive patients and that from the arithmetic mean value among negative patients were simultaneously maximized. The cut-off value of 2.7% at 20 min had the longest distance, being separated by 3.16 SD from the two mean values. Using this cut-off value, the urea breath test showed 100% specificity and 98% sensitivity for the diagnosis of Helicobacter pylori infection.

The aim of this study was to compare the performance characteristics of one serum and four whole blood rapid antibody tests for Helicobacter pylori infection.

A total of 97 outpatients referred for endoscopic evaluation of dyspepsia were included. Antral biopsies were obtained for histology and rapid urease test. Serum was tested with an enzyme-linked immunoassay (HM-CAP) and a rapid serology test (FlexSure HP). A commercially available 13C-urea breath test was performed. Capillary blood obtained by fingerstick was tested with FlexSure HP, QuickVue, Accustat, and StatSimple pylori tests. Sensitivity, specificity, and accuracy of each rapid test was calculated relative to a criterion standard of histological gastritis and at least two of the four following tests positive: identifiable organisms on specially stained slides, rapid urease test, urea breath test, or serum immunoassay.

A total of 30 patients (31%) were infected. The FlexSure HP Serum, and FlexSure HP, QuickVue, Accustat, and StatSimple pylori whole blood tests had sensitivities of 90%, 87%, 83%, 76%, and 90%; specificities of 94%, 90%, 96%, 96%, and 98%, and accuracies of 93%, 88%, 92%, 87%, and 96%, respectively. Sensitivities were not statistically different. StatSimple pylori was more specific than FlexSure HP whole blood (p<0.03), and more accurate than FlexSure whole blood (p<0.024) and Accustat (p< 0.01). Serum immunoassay was significantly more sensitive (97%) than FlexSure whole blood, QuickVue, and Accustat (p<0.01), but its specificity (95%) was not statistically different from the rapid tests.

Rapid antibody testing provides an accurate diagnosis of H. pylori infection. In general, these tests are less sensitive than, but as specific as, standard serology.

The laser assisted ratio analyser (LARA) was developed as a novel device to measure 13CO2 in the urea breath test for the detection of H. pylori infection. The analyser was tested in a prospective multicentre study in 444 patients in North America (Phase 1) followed by second study involving 160 patients (Phase 2).

Patients undergoing endoscopy for clinical indications had antral and gastric biopsies taken for histological examination, culture and CLO test. One hour after endoscopy, a baseline breath sample was obtained, 100 mg of 13C-urea were ingested and breath samples were obtained at 30 and 60 min post ingestion. Data obtained with the LARA were compared with the results of culture, rapid urease testing and central pathology in two different combinations {reference standards}. The study was conducted in two phases: in Phase 2, a modification was made to the LARA that improved the removal of water vapour from the breath sample.

In Phase I, data from 331 patients were analysed using a cut off of (delta) 7.8 +/- 0.8, the sensitivity of the method was 91.7% and the specificity was 86.5%, using the reference standard of 2 of 3 tests (CLO, culture or histology) being positive. Positive and negative predictive values were, respectively, 85.2% and 92.5%. In Phase 2 of the study, 160 patients were enrolled and 141 patients were analysed using the same standards. We used the same reference standards but with a cut off of (delta) 6.1 +/- 0.6. The sensitivity and specificity increased to 96.8% and 98.6%, respectively. Positive and negative predictive values were, respectively, 98.4% and 97.3%. The detection rates for H. pylori were similar in patients with peptic ulcer or H. pylori associated gastritis.

The LARA provides an accurate non-invasive means of detecting 13CO2 in the 13C-urea breath test for H. pylori in a multicentre clinical environment that compares well with invasive 'gold standard' methods.

Helicobacter pylori is an important pathogen responsible for significant morbidity and mortality. Its prevalence varies widely in different geographical locations and is especially high in parts of Asia.

A double-blind study was carried out to evaluate the use of the 5 microCi (185 KBq) [14C]-urea breath test ([14C]-UBT) in a South-East Asian population by validating its diagnostic accuracy against histology and the CLO test.

The sensitivity and specificity of the [14C]-UBT was 100% when compared against the CLO test. When histology was used as the 'gold standard', the sensitivity and specificity were 100% and 97.2%, respectively. There was no overlap or indeterminate values between positive and negative results on the [14C]-UBT.

Among South-East Asian populations where the prevalence of H. pylori infection is high, the high sensitivity of the 5 microCi [14C]-UBT makes it a very important test in the detection of H. pylori.

The causal association between Helicobacter pylori (H. pylori) colonization of the gastric mucosa and gastritis is now well established. Histologic examination of endoscopic biopsy specimens has long been regarded as the gold standard for diagnosis. However, the changes can be focal in nature and presence of the organism may be missed in nonsampled areas. The urea breath test, which uses a stable isotope, offers distinct advantages, in that it is noninvasive and measures the activity of the micro-organism. It thus represents a potentially invaluable tool in the initial diagnosis of the infection and in verifying its eradication.

The study design was that of a prospective, blinded comparison of the [13C]-urea breath test with histologic assessment of antral biopsy specimens using the Warthin-Starry stain, to diagnose H. pylori infection in a group of 79 consecutive pediatric patients.

Patients classified as negative by histology (n=67) had breath 13C enrichment of 0.97+/-0.07 delta per thousand (mean+/-SEM), with a range of -0.20 and 2.83 delta per thousand. In contrast, those with a positive histologic results (n=12) had an enrichment of 25.41+/-5.01 delta per thousand (range, 3.43-58.80; p < 0.001). At the chosen cutoff point of 3 delta per thousand, the sensitivity and specificity as well as the positive and negative predictive values of the breath test were uniformly 100%.

The [13C]-urea breath test is a highly reliable, noninvasive method for the diagnosis of H. pylori gastritis in children and adolescents.

Helicobacter pylori antibody testing is accurate for diagnosing untreated patients. Rapid serum testing is as accurate as formal enzyme-linked immunosorbent assay (ELISA) testing. As whole blood fingerstick tests may become the diagnostic method of choice if they are of similar accuracy, 51 patients were studied who had not taken antibiotics, bismuth, sucralfate, or proton pump inhibitors. Concordance between C-14 Urea Breath Testing and HM-CAP ELISA testing served as the study standard for H. pylori diagnosis. Rapid antibody testing was performed with the AccuStat whole blood (Boehringer Mannheim, Mannheim, Germany) and FlexSure HP (Smith Kline Diagnostics, San Jose, CA) serum tests. Antral biopsy for CLO testing and histological evaluation with thiazine staining were available for 18 (35.3%) and 20 patients (39.2%), respectively. Nineteen of 50 patients (38%) were infected. (One patient had discordant tests and was excluded.) FlexSure HP and AccuStat were each positive in 18 (36%) and 19 patients (38%) with sensitivity, specificity, and positive and negative predictive values of 89.5% and 89.5%, 96.8% and 93.5%, 94.4% and 89.5%, and 93.8% and 93.5%, respectively. There were two false-negative FlexSure HP and AccuStat tests and three false-positive tests--1 FlexSure and 2 AccuStat results. CLO test and histology concurred in every case tested. We conclude that both rapid antibody tests are accurate and suitable for screening patients not previously treated for H. pylori infection. Since the AccuStat has preserved diagnostic strength, is less costly, takes less time, and is less labor intensive, whole blood testing is the screening test of choice.

Multiple invasive and noninvasive tests for detecting Helicobacter pylori infection are available. The current "gold standard" for the diagnosis of H. pylori infection requires histology and the rapid urease test. Our aim was to test the performance of immunoglobulin A (IgA) and IgG immunoblot assays in comparison with that of the gold standard tests for the diagnosis of H. pylori infection. Ninety patients who underwent gastroscopy were analyzed in a prospective study. Fifty-nine of them were defined to be H. pylori positive by the gold standard tests. The IgA and IgG immunoblot assays correctly identified H. pylori infection in 17 and 58 of these patients, respectively, indicating that determination of IgA antibodies seems to be of low diagnostic value for H. pylori infection. In contrast, the sensitivity and specificity of the IgG immunoblot assay were 98 and 71%, respectively, with positive and negative predictive values of 87 and 96%, respectively. Therefore, the IgG immunoblot assay proved to be a sensitive and useful, noninvasive test for the diagnosis of H. pylori infection.

To determine whether the urease-based CLOtest or low-dose 14C urea breath test can predict severity of gastritis or the presence of peptic ulcers, we studied 84 patients presenting for upper endoscopy. Antral biopsies were obtained for histologic analysis and CLOtesting, and urea breath testing was performed. The time to a positive CLOtest and the breath test peak values were correlated with endoscopic findings, severity of gastritis, and bacterial burden. Twenty-four patients had positive urea breath test results (22 with positive CLOtests). Patients with positive breath test results were more likely to have duodenal ulcers, higher grades of gastritis, and increased bacterial burden (p < 0.01 for all comparisons). Correlation between the time to a positive CLOtest or peak breath test values and gastritis severity or bacterial burden was poor (p > 0.05 for all comparisons). In patients with positive tests, no difference was observed between the time to a positive CLOtest or peak breath test value in patients with or without peptic ulcers (p < 0.2 for all comparisons). The low-dose 14C urea breath test and the CLOtest are both accurate for Helicobacter pylori diagnosis. However, neither test predicts the severity of the gastritis, the degree of bacterial burden, or the presence of peptic ulcers.

H. pylori is more easily visualized with special stains than with H&E, but this adds time and expense to the diagnostic workup. We sought to determine if the diagnostic accuracy was improved with special stains.

One hundred-one patients had two "jumbo" biopsies taken from the gastric antrum and two from the body for examination with H&E, Genta, and Giemsa stains. Four separate biopsy specimens were also taken from the antrum and the body for culture and for three types of rapid urease test, and 13C-urea breath tests were also performed. Mixed, coded biopsies were assessed for H. pylori, and density was scored from 0 to 4. A case was considered positive for H. pylori if culture was positive, two rapid urease tests and a urea breath test were positive, or two different stains were positive. Biopsy specimens were excluded from analysis if the slides were missing or there was inadequate tissue for review, or if the specimen showed a lack of staining.

Fifty-two (13%) of 404 specimens were excluded because of a poor Genta stain. Sensitivities were comparable for the three stains (H&E, 92%; Giemsa, 88%; Genta, 91%), while H&E specificity (89%) was significantly lower than that of the special stains (98%). Sensitivity for all three stains was significantly lower at low (grade 0 to 1) H. pylori density than at high (grade 2 to 4) density (H&E, 70% vs 98%; Giemsa, 64% vs 96%; Genta, 66% vs 97%), and 20 of 22 false positives were grade 1.

The sensitivities of H&E and special stains are comparable at around 90%, but the specificity of H&E is significantly lower. The Giemsa stain appears to be the preferred stain for H. pylori diagnosis on the basis of its good sensitivity, excellent specificity, and lack of technical difficulty in preparation. However, H&E provides excellent accuracy when more than minimal (grade 1) H. pylori density is present.