The stool antigen test (SAT) is a convenient noninvasive option for the diagnosis of Helicobacter pylori ( H. pylori ) infection. However, despite having been previously evaluated, there is currently a lack of evidence regarding the comparative accuracy of conventional and rapid SATs utilizing monoclonal or polyclonal antibodies in adults. Here, we perform a thorough statistical synthesis to determine and compare the diagnostic accuracy of conventional and rapid SATs for the diagnosis of H. pylori infection in adults.

We conducted independent searches through July 25, 2023, for studies evaluating the accuracy of SAT against a reference standard. We assessed methodological quality using Quality Assessment of Diagnostic Accuracy Studies-2 and calculated overall accuracy measures using the bivariate random-effect model. We also conducted subgroup analyses based on model and assessment technique, and Spearman correlation analysis to investigate a possible threshold effect. We generated summary receiver operating characteristic curves to assess heterogeneity and evaluated publication bias.

Conventional SAT demonstrated superior sensitivity (92.19% vs 85.79%), specificity (92.93% vs 91.18%), likelihood ratios (LR+ 9.68 vs 8.16; LR- 0.10 vs 0.15), and area under the curve (0.958 vs 0.940) compared with rapid SAT. Notably, the diagnostic odds ratio for conventional SAT (114.70) significantly outperformed rapid SAT (diagnostic odds ratio: 57.72). Correlation analysis revealed no threshold effect and summary receiver operating characteristic curves showed consistent accuracy for both tests.

Our study establishes evidence of the superior diagnostic accuracy of conventional SATs over rapid SATs for detecting H. pylori infection in adults. Also, we provide valuable insights into the impact of using monoclonal or polyclonal antibodies and different assessment techniques on diagnostic accuracy measures.

Paratuberculosis (PTB) or Johne's disease is a chronic intestinal infection of ruminants, caused by Mycobacterium avium subsp. paratuberculosis. The shedding of mycobacteria in the feces starts at the initial stages and increases with disease progression, suggesting that antigens secreted by mycobacteria could be excreted in the feces. Previously, we demonstrated that the alanine and proline-rich antigen (Apa), a secretory antigen of Map, could be detected in the intestine of cows with PTB using a monoclonal antibody. In this study, we verified whether this protein can be found in consistently detectable levels in the feces of cattle with PTB. Feces were obtained from cows with Johne's disease confirmed by laboratory tests, cows with suspected PTB based on seropositivity and from PTB-free control cows. Samples were immunoprecipitated using anti-Apa monoclonal antibody and analyzed by immunoblot. The Apa was detected as a 60/70 kDa doublet band in all samples obtained from animals with laboratory-confirmed disease and in a substantial proportion of seropositive asymptomatic animals, but not in the control samples. Additionally, the antigen was detected in the feces of animals with Johne's disease by ELISA. This study strongly suggests that Apa is a potential fecal biomarker of Johne's disease that could serve for immunodiagnosis.

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.

Limited research has been published on current Helicobacter pylori infection rate in asymptomatic children in China.

To assess current Helicobacter pylori infection rate, distribution characteristics and risk factors in Chinese asymptomatic children.

A prospective, cross-sectional, population-based study was performed from 2009 to 2011 in three cities of China. Helicobacter pylori infection was diagnosed by a stool antigen test. Multi-stage cluster random sampling was used to select asymptomatic children including neonates. Socioeconomic details were obtained through a standardised questionnaire.

Among total of 3491 children (0-18 years), the global infection rate was 6.8% and there were no significant differences between genders. Age specific infection rate between regions was significantly different (P < 0.05). The infection rate significantly increased with age (P for trend <0.01). It was low during the newborn (0.6%) to preschool period and was significantly increased in high school students (13.5%) (P < 0.01). Multivariable regression indicated that hand sanitisation, individually served meals, higher education level of mother, above average living space and residence in urban areas were significantly protective against infection (OR 0.749, 0.698, 0.720, 0.838 and 0.770 respectively). Conversely, consuming meals in unsanitised conditions, sharing towels, receiving pre-chewed food from the mother, artificial feeding and family history of gastrointestinal disease were significantly associated with the risk of infection (OR 1.200, 1.965, 2.002, 1.071 and 2.093 respectively).

Helicobacter pylori infection rate increases with age in Chinese asymptomatic children and is common after 10 years of age. The rate of infection is related to socioeconomic status.

Helicobacter pylori (H. pylori) is the most common chronic bacterial infection in humans. Chronic colonization increases the risk of duodenal ulcer and gastric cancer. The risk factors for acquiring the infection have been extensively studied. However, there are conflicting results on the role of breastfeeding in the prevention of H. pylori infection. We conducted a study to evaluate the effects of breastfeeding on the H. Pylori infection in Kurdish children in Sanandaj, IR Iran.

A historical cohort study was carried out from January 2011 through December 2012. Totally 221 children who were going to attain 2 years old during the study period were randomly enrolled. They were divided into two groups, i.e. breastfed and non-breastfed. We used H. pylori stool antigen test to detect infection in the selected group of children after age of 2 years and cessation of breastfeeding. Each group was subdivided into two subgroups, infected and non-infected. The associations of breastfeeding with H. pylori infection was assessed using statistical software.

We found no difference in the odds of infection between breastfed and non-breastfed groups (OR=0.809, 95% CI [0.453-1.444]). An association between age and the prevalence of infection was found (P=0.008). There was an increase in the odds of infection as the family size grew (OR=1.93, 95% CI [1.04-3.6]) as well as increasing housing density (OR=2.12, 95% CI [1.10-4.10]).

The data suggests that breastfeeding in infancy does not protect against H. pylori infection for long duration among studied children in Iran. The protective effects of breastfeeding, if any, are at most transient.

Several noninvasive diagnostic tests based on the detection of Helicobacter pylori stool antigen (HpSA) have been developed. The aim of the study was to compare the diagnostic accuracy of 5 HpSA tests-2 monoclonal enzyme immunoassay tests (EIAs: the Premier Platinum HpSA Plus test and Helicobacter pylori Antigen (Hp Ag) test) and 3 rapid immunochromatographic assay (ICA) tests (the ImmunoCard STAT! HpSA test, one step HpSA test, and H. pylori fecal antigen test)--for diagnosing H. pylori infection in adult patients with dyspeptic symptoms before eradication therapy.

A total of 198 patients with dyspeptic symptoms were included in the study. A gastric biopsy was collected for histopathology and rapid urease testing. Stool specimens for HpSA testing were also collected. Patients were considered H. pylori positive if two invasive tests (histological and rapid urease tests) were positive.

The sensitivity and specificity were 92.2% and 94.4%, respectively, for the Premier Platinum HpSA Plus test; 48.9% and 88.9%, respectively, for the HP Ag test; 86.7% and 88.9, respectively, for the One Step HpSA test; 68.9% and 92.6%, respectively, for the ImmunoCard STAT! HpSA test; and 78.9% and 87%, respectively, for the H. Pylori fecal antigen test.

The Premier Platinum HpSA Plus EIA test was determined to be the most accurate stool test for diagnosing H. pylori infections in adult dyspeptic patients. The currently available ICA-based tests are fast and easy to use but provide less reliable results.

Development of a specific immunoassay to detect Helicobacter pylori infection in stool samples requires monoclonal antibody against the specific antigen. The aims of this study were to establish monoclonal antibodies against the 26 kDa protein of H. pylori and develop an immunodot blot for their application to recognize H. pylori infection using stool samples. Mice were immunized intraperitoneally with homogenized gel containing the 26 kDa band of cell surface proteins of H. pylori in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The monoclonal antibodies were produced using the hybridoma technique. Reactivity of monoclonal antibodies was tested with the purified 26 kDa antigen and cell surface proteins from cultured H. pylori by ELISA. Furthermore reactivity of monoclonal antibodies was tested on negative and positive stool samples for H. pylori and suspensions of several major bacteria in stool by immunodot blot assay. Five stable hybridoma monoclones were obtained. The concordant reactivity of the monoclonal antibodies with H. pylori present in the stool samples, which had been tested previously using an ACON ELISA kit for H. pylori stool antigen testing, and unreactivity with several different major fecal bacteria in immunodot blotting indicates high specificity of the immunodot blot based on the reaction of produced monoclonal antibodies with the H. pylori antigen in stools. The findings indicate that the novel immunodot blot developed based on new monoclonal antibodies for stool antigens would be useful as a noninvasive method of diagnosing H. pylori infection.

In developing countries, Helicobacter pylori infection is mainly acquired during childhood and may be a predisposing factor for peptic ulcer or gastric cancer later in life. Noninvasive diagnostic tools are particularly useful in children for screening tests and epidemiological studies. We aimed to determine the prevalence of H. pylori infection among Kurdish children in Sanandaj, West Iran.

We used a Helicobacter Pylori Stool Antigen (HpSA) test to detect H. pylori infection. A questionnaire was used to collect data about age, sex, duration of breastfeeding, and family size. A total of 458 children aged 4 months to 15 years were enrolled in this study.

The mean age of enrolled children was 5.6±5.4 years. Stool samples were positive for H. pylori in 294 (64.2%) children. The prevalence of H. pylori infection increased with age (P<0.001). We found a significant increase in the infection rate as the family size grew (P=0.005). There was no correlation between a positive H. pylori status and gender (P=0.6) or the duration of breastfeeding (P=0.8).

It seems that the prevalence of H. pylori infection is very high in children in Sanandaj. It begins at early infancy (before 4th month of age) and cumulatively increases with age.

Initial assessment of dyspepsia often includes noninvasive testing for Helicobacter pylori infection. Commercially available tests vary widely in cost and accuracy. Although there is extensive literature on the cost-effectiveness of H. pylori treatment, there is little information comparing the cost-effectiveness of various currently used, noninvasive testing strategies.

A Markov simulation was used to calculate cost per symptom-free year and cost per correct diagnosis. Uncertainty in outcomes was estimated using probabilistic sensitivity analysis.

Under the baseline assumptions, cost per symptom-free year was $122 for empiric proton pump inhibitor (PPI) trial, and costs for the noninvasive test strategies ranged from $123 (stool antigen) to $129 (IgG/IgA combined serology). Confidence intervals had significant overlap.

Under our assumptions for how testing for H. pylori infection is employed in United States medical practice, the available noninvasive tests all have similar cost-effectiveness between one another as well as with empiric PPI trial.

The aim of the study was to assess a new latex agglutination (LA) stool antigen assay (PYLOGEN; CerTest Biotec, Zaragoza, Spain) in the diagnosis of Helicobacter pylori infection and to monitor its eradication after treatment. The LA test has been approved for sale in Europe, and its approval from the US Food and Drug Administration is still pending. The individuals enrolled were classified into 3 groups of patients: Group 1 consisted of 38 patients who are H. pylori positive. The diagnosis of H. pylori infection was established if there was concordance between 2 test results (urea breath test [UBT], rapid urease test, and histopathologic study) or if the culture alone was positive. Patients with only 1 positive test were considered indeterminate and were excluded from the study. Group 2 comprised 9 patients without positive tests and who were considered to be H. pylori negative. Group 3 consisted of 57 patients who received eradication treatment. The sensitivity and specificity of the test were 78.9% and 100%, respectively. The results of the UBT of the patients were studied 6 weeks after eradication therapy. The sensitivity and specificity of the LA test relative to UBT for patients after treatment were 75% and 93.3%, respectively.

We evaluated two protocols for isolation of Helicobacter pylori in stool from biopsied and nonbiopsied children. Twenty-three child patients whose presumptive positivity or negativity was diagnosed by endoscopy and a rapid urease test at site were used to compare biopsy-based tests with stool-based tests (H. pylori stool antigen test and stool culture). Their gastric activity and bacterial density were graded by the updated Sydney system. Biopsy and stool specimens were cultured on Campy-blood and Belo horizonte agar plates after enrichment in selective Campy-Thio medium. To compare two stool culture protocols, stools from 20 nonbiopsied children were tested by the HpSA test and cultured either as above or after treatment with cholestyramine. Grown colonies were screened by Gram staining, slide agglutination using anti-H. pylori monoclonal IgG; positive isolates were tested by biochemical tests and polymerase chain reaction for H. pylori-specific ureA gene. Coccoid H. pylori was isolated in stool samples from the biopsied patients whose bacterial density was two to four in histology. Their oxidase was slightly positive but became positive after two subcultures, while additional biochemical tests confirmed the isolation of H. pylori. Similar coccoid but oxidase positive H. pylori was isolated from three nonbiopsied children with the protocol of cholestyramine treatment only. The density of bacteria in the stomach may influence the recovery of H. pylori from stool; inactivation of bile with cholestyramine improves the yield in culture and favors isolation of an enhanced metabolic form of bacteria.

The discovery of Helicobacter pylori in 1982 was the starting point of a revolution concerning the concepts and management of gastroduodenal diseases. It is now well accepted that the most common stomach disease, peptic ulcer disease, is an infectious disease, and all consensus conferences agree that the causative agent, H. pylori, must be treated with antibiotics. Furthermore, the concept emerged that this bacterium could be the trigger of various malignant diseases of the stomach, and it is now a model for chronic bacterial infections causing cancer. Most of the many different techniques involved in diagnosis of H. pylori infection are performed in clinical microbiology laboratories. The aim of this article is to review the current status of these methods and their application, highlighting the important progress which has been made in the past decade. Both invasive and noninvasive techniques will be reviewed.

Data evaluating the monoclonal tests for determination of cure after Helicobacter pylori treatment are scarce.

This study was aimed to evaluate the usefulness of 4 stool tests-2 new RAPID monoclonal immunochromatographic tests (RAPID Hp StAR, DakoCytomation, Cambridge, UK and ImmunoCard STAT! HpSA, Meridian Diagnostics, Cincinnati, OH) a monoclonal EIA test (Amplified IDEIA Hp StAR, DakoCytomation, Cambridge, UK), and a polyclonal EIA test (Premier Platinum HpSA, Meridian Diagnostics, Cincinnati, OH)-to confirm cure of H. pylori infection after eradication treatment.

Ninety-seven patients who underwent eradication treatment were included. Cure of H. pylori infection was determined using 2 consecutive reference tests. Fecal tests were performed according to the specifications of the manufacturer. Sensitivity, specificity, and positive and negative predictive values were calculated.

After H. pylori eradication, the RAPID Hp StAR test has a sensitivity of 73% for detecting persistent infection, a specificity of 96% to 98%, a positive predictive value of 73% to 80% and a negative predictive value of 96%. For ImmunoCard STAT! HpSA the corresponding values were 91%, 97%, 77%, and 99%, for Amplified IDEIA Hp StAR 73%, 97%, 73%, and 97%, and for Premier Platinum HpSA 91%, 79%, 35%, and 98%.

All tests except Premier Platinum HpSA were highly accurate confirming eradication after treatment.

Many noninvasive methods (using breath, blood, and stool samples) are available to diagnose Helicobacter pylori. However, because the noninvasive tests are proxy measures of the infection, they need validation before use. Factors that may affect test validity include patient age, gender, and geographic location. Because no data were available on the validation of noninvasive tests for the diagnosis of H. pylori among children in the Middle East, this study was performed.

Children between 2 and 17 years of age evaluated at the Cairo University School of Medicine pediatric gastroenterology clinic who were already scheduled for upper endoscopy were eligible for enrollment in the study. At the time of endoscopy, 3 biopsies were collected and used for rapid urease, histology, and culture, respectively. All children also donated a sample of stool and blood and had a urea breath test performed. Stool and serum samples were tested for the presence of H. pylori by using commercially available enzyme-linked immunosorbent assay-based technology. The sensitivity, specificity, and positive and negative predictive values were calculated for each noninvasive test used in the study. Receiver operating curves also were charted to determine optimal cut points for the various tests when used in the current study cohort.

One hundred eight children were enrolled in the study, with 52 children being under 6 years of age. The urea breath test and HpStar (DakoCytomation, Norden, Denmark) stool enzyme-linked immunosorbent assay kit had the highest sensitivity and specificity (sensitivity and specificity: 98 and 89 [urea breath test] and 94 and 81 [HpStar], respectively), whereas the serologic kit had an unacceptably low sensitivity (50%). The sensitivity of neither the urea breath test nor the HpStar tests was affected by subject age, but specificity of the HpStar test, although still high, was significantly lower among children under 6 years. Receiver operating curves found optimal cut points of the urea breath test at 6.2 delta over baseline and of the HpStar at 0.25 enzyme-linked immunosorbent assay units.

The urea breath test and HpSTAR stool antigen kit are reliable tests for the noninvasive diagnosis of H. pylori among children living in the Middle East.

To perform a systematic review and a meta-analysis of accuracy of monoclonal stool antigen test (SAT) for the diagnosis of Helicobacter pylori infection.

assessing the accuracy of monoclonal SAT for the diagnosis of H. pylori infection.

electronic and manual bibliographical searches.

independently done by two reviewers.

meta-analyses combining the sensitivities, specificities, and likelihood ratios (LRs) of the individual studies.

Twenty-two studies, including 2,499 patients, evaluated the monoclonal SAT before eradication therapy. Pooled sensitivity, specificity, LR+, and LR- were: 0.94 (95% CI 0.93-0.95), 0.97 (0.96-0.98), 24 (15-41), and 0.07 (0.04-0.12). The accuracy of both monoclonal and polyclonal SAT was evaluated together in 13 pretreatment studies, and higher pooled sensitivity was demonstrated with the monoclonal technique (0.95 vs 0.83). Twelve studies, including 957 patients, assessed the monoclonal SAT to confirm eradication after therapy. Pooled sensitivity, specificity, LR+, and LR- were 0.93 (0.89-0.96), 0.96 (0.94-0.97), 17 (12-23), and 0.1 (0.07-0.15). Both tests were evaluated together in eight post-treatment studies and, again, the monoclonal technique showed higher sensitivity (0.91 vs 0.76). Heterogeneity among studies disappeared when a single outlier study was excluded. Subanalysis depending on the reference method, the study population, or the study quality showed similar results.

Monoclonal SAT is an accurate noninvasive method both for the initial diagnosis of H. pylori infection and for the confirmation of its eradication after treatment. The monoclonal technique has higher sensitivity than the polyclonal one, especially in the post-treatment setting.

Detection of Helicobacter pylori antigen in stool samples has been a subject of controversy. However, it has been included in several clinical guidelines as a recommended non-invasive testing procedure in dyspeptic patients.

To compare a monoclonal enzyme immunoassay for detection of H. pylori stool antigen (Amplified IDEIA HpStAR, DakoCytomation) with a polyclonal enzyme immunoassay (HpSA test, Premier Platinum HpSA, Meridian Diagnostics) in diagnosing infection and in determining H. pylori status after eradication treatment.

We evaluated stool samples of 198 patients diagnosed with H. pylori infection and of 41 patients without infection. The results of the monoclonal enzyme immunoassay HpStAR were compared with those of the polyclonal enzyme immunoassay HpSA.

The sensitivity and specificity of HpStAR were 91.9% and 70.7%, while those of HpSA were 89.4% and 80.5%, respectively. In the 126 patients evaluated 6 weeks after eradication therapy, the overall agreement between urea breath test and HpStAR was 90.5% (P = 0.710) and between urea breath test and HpSA was 76.9% (P = 0.410).

HpStAR is a rapid and easy-to-perform test with similar sensitivity to HpSA in the diagnosis of H. pylori infection, although it had lower specificity. In contrast, HpStAR is more accurate after eradication therapy than HpSA.

To evaluate two enzyme immunoassay-based stool antigen tests, Premier Platinum HpSA and Amplified IDEIA HpStAR, and one rapid test, ImmunoCard STAT! HpSA, in the primary diagnosis of Helicobacter pylori (H pylori) infection and after eradication therapy.

Altogether 1 574 adult subjects were screened with a whole-blood H pylori antibody test and positive results were confirmed with locally validated serology and (13)C-urea breath test. All 185 subjects, confirmed to be H pylori positive, and 97 H pylori-negative individuals, randomly selected from the screened study population and with negative results in serology and UBT, were enrolled. After eradication therapy the results of 182 subjects were assessed.

At baseline, the sensitivity of HpSA and HpStAR was 91.9% and 96.2%, respectively, and specificity was 95.9% for both tests. ImmunoCard had sensitivity of 93.0% but specificity of only 88.7%. After eradication therapy, HpSA and HpStAR had sensitivity of 81.3% and 100%, and specificity of 97.0% and 97.6%, respectively. ImmunoCard had sensitivity of 93.8% and specificity of 97.0%. HpSA, HpStAR, and ImmunoCard had PPV 77%, 80%, and 75%, and NPV 98%, 100%, and 99%, respectively.

In primary diagnosis, the EIA-based tests performed well. After eradication therapy, negative results were highly accurate for all the three tests. HpStAR had the best overall performance.

Helicobacter pylori infection is acquired mainly in childhood, especially in developing countries, where a low-cost, rapid diagnostic technique which is reliable for all age groups may be useful for the management of H. pylori infection. For this purpose, we used an HpSA test (Equipar) to detect H. pylori infection in children and adolescents from Tehran, Iran. Thirty-five children who were positive or negative for H. pylori infection by endoscopy-based tests were used as positive and negative controls for the HpSA test. Stools were collected from 430 randomly selected children and adolescents (4 to 18 years old) from southwest, near the center, and northwest of Tehran. A questionnaire that included presence of recurrent abdominal pain (RAP), family history of infection and/or peptic ulcer disease (PUD), and income of parents was completed. A good agreement was found between the results of endoscopy-based tests and those of the HpSA test; the sensitivity and specificity of the Equipar-HpSA test were 100% and 83.4%, respectively. Among 430 children and adolescents, 47% were positive by the HpSA test, of whom 82% had RAP. No difference in incidence was observed between the two sexes; the various categories of age showed an increasing incidence, ranging from 24% (ages 4 to 6) to 58% (ages 16 to 18). The rate of infection in children and adolescents from the southwest was significantly higher (70%) than the rate in those from the northwest (32%), and a family history of H. pylori infection or PUD was observed in 59% of the HpSA positive subjects. The HpSA test is a useful test to detect H. pylori infection in children and adolescents from developing countries.

Reliable and readily available non-invasive methods are needed for detection of Helicobacter pylori infection and assessment of eradication therapy. In H. pylori-positive subjects we compared three stool antigen tests (Premier Platinum HpSA, Amplified IDEIA HpStAR and ImmunoCard STAT!HpSA) with invasive tests before their eradication therapy, and with non-invasive diagnostic methods after their therapy.

A total of 82 adults with dyspepsia (aged 24-79 years) with an H. pylori-positive rapid urease test were enrolled in the study. Before therapy, H. pylori status was also confirmed with histology, culture and serology. After eradication, success was assessed with the [13C]-urea breath test (UBT) and usually also with serology.

At baseline, sensitivities of these stool antigen tests were 90.2% for HpSA, 97.6% for HpStAR and 96.3% for ImmunoCard. Eradication therapy was successful in 66 patients and unsuccessful in 16. Sensitivity and specificity of the three stool antigen tests in the post-eradication setting were, respectively, 75.0% and 95.5% for HpSA, 93.8% and 98.5% for HpStAR and 87.5% and 95.5% for Immunocard.

The performance of all three stool antigen tests in the post-treatment setting was slightly inferior to that of the UBT test and serology, with monoclonal antibody-based tests showing better results.

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.

There are few reports which the tests used for diagnosing Helicobacter pylori infection and monitoring its eradication in children.

Prospective evaluation of invasive (gastric histology, rapid urease test [RUT]) and non-invasive (stool antigen [FemtoLab H. pylori], urea breath test [UBT]) tests in the diagnosis of H. pylori infection and post-treatment eradication in children and adolescents.

Ninety-two patients (50 male, 42 female) referred for upper gastrointestinal endoscopy were prospectively enrolled. UBT was performed and stool specimens collected for monoclonal enzyme immunoassay for H. pylori antigen (FemtoLab) 1 to 4 days before endoscopy. H. pylori in gastric biopsies was evaluated by RUT and staining with hematoxylin-eosin and giemsa. Eradication therapy was given to children with abdominal pain and H. pylori gastritis. FemtoLab H. pylori and UBT were repeated 6 weeks after the end of triple therapy.

Histology identified H. pylori in 49 of 92 (53%) subjects. Concordance between histology and RUT was found in 78 of 92 children. FemtoLab H. pylori was positive in 41 of 78 (52.6%) children with sensitivity, specificity, positive and negative predictive values of 97.5%, 94.7%, 95.1% and 97.3%, respectively. For UBT, these values were 100%, 96.9%, 97.5% and 100%, respectively. Twenty-six of 36 patients who received triple therapy returned for eradication evaluation. Tests for H. pylori antigen in stool were positive in 10 of 26 and for UBT in 11 of 26.

Stool antigen (FemtoLab) and UBT were equally effective in diagnosing and confirming eradication of H. pylori infection in children.

Recent availability of tests for Helicobacter pylori antigens in stool samples has provided potentially useful tools for epidemiological studies and clinical settings. The aim of this study was to evaluate a monoclonal antibody-based H. pylori antigen stool test in the primary diagnosis of H. pylori infection, and to study the test performance after patients were treated with lanzoprazole, and after eradication therapy.

The study included 122 dyspeptic patients. At gastroscopy, biopsy specimens were obtained for culture and histology. Stool antigen and [14C]-urea breath tests were performed concurrently. Positive culture alone or a positive [14C]-urea breath test in combination with positive histology defined the reference standard. Forty-three Hp +ve patients were treated with lanzoprazole for 2 to 4 weeks, and stool antigen tests were performed on days 1 and 7 post-treatment. After eradication therapy, 32 patients were re-examined for H. pylori infection.

Prevalence of H. pylori was 44.3%. Sensitivity and specificity for the stool antigen test in the primary diagnosis of H. pylori infection were 98% and 94%, with positive and negative likelihood ratios of 16.7 and 0.02, respectively. All patients had positive stool tests immediately after lanzoprazole treatment, whereas 2 patients had negative stool tests after 7 days. Triple therapy rendered all patients stool test negative.

The monoclonal antibody-based stool antigen test is an accurate tool in the primary diagnosis of H. pylori infection and after eradication therapy. Lanzoprazole treatment does not influence the clinical performance of the test.

Helicobacter pylori infection is acquired mainly in early childhood. Much is unknown about the mode of transmission. The organism can be cultivated from cathartic stools and vomitus and is potentially transmissible during episodes of gastrointestinal tract illness. Because Shigella and Salmonella are common pathogens in enteric infections in children, we examined the association of H. pylori with Shigella and Salmonella infections in pediatric patients.

The study population included consecutive children aged 2-72 months hospitalized with acute gastroenteritis who had culture-proven shigellosis (N = 78) or salmonellosis (N = 76). Sixty-five healthy similarly aged children with culture-negative stools served as controls. Parents of cases were queried for personal and family characteristics and socioeconomic indicators. The stool specimens from all participants were tested for H. pylori antigen.

On univariate analysis, Shigella gastroenteritis was significantly associated with H. pylori positivity (odds ratio, OR: 3.5, 95% confidence interval (CI): 1.5-8.8, p= 0.004) compared to controls. This association remained significant even after adjusting for living conditions, father's occupation, and father's education (OR = 3.38, 95% CI: 1.39-8.22, p= 0.007). Salmonella gastroenteritis was not associated with H. pylori positivity (OR = 1.1; 95% CI: 0.4-3.0, p= 0.8).

H. pylori infection in young children is associated with Shigella gastroenteritis. This association warrants further investigation.

While there are some attempts to improve culture of Helicobacter pylori, molecular methods have been the main focus of this interest. Their main application concerns the development of rapid tests also allowing the determination of bacterial resistance, i.e. real-time polymerase chain reaction (PCR) or fluorescence in situ hybridization (FISH), or to genotype the strains. Attempts to improve, simplify or explain the discrepancies of urea breath test results have been made and new generation of stool antigen test with monoclonal antibodies either using the standard ELISA format or rapid immunoenzymatic detection have confirmed their value. With regard to serology, studies have mainly focused on the distinction of infections with more pathogenic strains and the ability to diagnose atrophic gastritis with the Gastropanel.