Rapid Stool Antigen Test Research Articles

Acurateţea testelor neinvazive la copii pentru precizia diagnosticului de infecţie cu Helicobacter pylori

Helicobacter pylori infection is aquired in childhood, af­fects more than half of the world population and is as­so­cia­ted with chronic gastritis. The majority of the in­fec­ted children are asymptomatic. The most frequently used tests for the detection of Helicobacter pylori are ¹³C urea breath test and stool antigen test. Objective. In this stu­dy, we evaluated the accuracy and the utility of the ¹³C urea breath test and Helicobacter pylori stool antigen test in young children. We performed a prospective ob­ser­­va­­tio­nal study of 52 symptomatic children, mostly with uninvestigated dyspepsia suggestive for an or­ga­nic di­sease. The ¹³C urea breath test was used as gold stan­dard method for the diagnosis of Helicobacter py­lo­ri in­fec­tion. Forty-two of the 52 studied children had a po­si­tive ¹³C urea breath test, respectively 21 of 42 Heli­co­bac­ter pylori infected children presented a positive rapid stool antigen test for Helicobacter pylori. Our study did not reveal a strong agreement between Helicobacter py­lo­ri rapid stool antigen test and ¹³C urea breath test. The management of Helicobacter pylori infection in chil­dren remains a problem in clinical practice, therefore test­ing for Helicobacter pylori infection has become a very important part of the diagnostic process. Another mul­ti­cen­ter study from our country is recommended.

Rapid stool antigenic test for typhoid fever among suspected cases, Northeast, Ethiopia

Typhoid fever continued to be the key cause of morbidity and mortality in developing countries with poor hygienic practices and limited access to safe drinking water. The Widal card agglutination test is the main diagnostic tool in Ethiopia, which is limited in differentiating the overlapping symptoms with other acute febrile illnesses such as malaria and viral enteritis. This eventually leds to unnecessary antibiotic use and eventual drug resistance. Therefore this study wants to assess the burden and associated potential risk factors of typhoid fever among suspected cases using the typhoid rapid stool antigen test in Northeast Ethiopia. A hospital-based cross-sectional study was conducted at Gaint and Meket Shediho primary hospitals from May to July 2021. A total of 255 patients clinically suspected of typhoid fever, and willing to grant informed consent were included systematically. The demographic and hygiene-related variables were collected using a pre-tested structured questionnaire. The rapid stool antigenic test and xylose-lysine-deoxycholate agar (XLD) stool culture were evaluated for the level of agreement. The present study indicated that the prevalence of typhoid fever was 15.3%. This displayed that the human-restricted infectious disease, typhoid fever remained a challenge to Ethiopians. Washing hands with soap, history of typhoid fever, having previous history of hospitalization, and chronic underlying disease was the significant potential factor for typhoid fever. The higher agreement of the rapid stool antigenic test with the stool culture can indicate the factual burden of typhoid fever in the suspected population. This could minimize empiric treatment and the possible emergence of drug resistance. Thus, resource-poor settings may need to look for a rapid and reliable stool antigenic test.

Comparative study between noninvasive techniques for diagnosis of helicobacter pylori in patients with dyspepsia

Background and Aim Helicobacter pylori (H. pylori) is a common etiology for infection-related cancers and represents 5.5% of global cancer burden that increases the need for more sensitive noninvasive diagnostic techniques. The aim was to evaluate the role of saliva and stool samples in the diagnosis of H. pylori infection to replace invasive techniques and to compare between three noninvasive diagnostic tests: salivary culture, PCR, and rapid stool antigen test (RSAT). Patients and methods The study was conducted on 45 patients with dyspepsia and 45 healthy participants as a control. Saliva and stool samples were taken from all groups and subjected to culture, PCR for detection of 16SrRNA gene of H. pylori, and RSAT to detect H. pylori. Gastric biopsy samples were taken for H. pylori culture, rapid urea test, and histopathology from 20 patients. Results A total of 15.6% specimens were positive by salivary culture in patients’ group and 2.2% specimens were positive in the control group. About 31% were positive by salivary PCR in patients’ group and 6.7% were positive by salivary PCR in the control group. About 71% were positive by RSAT in patients and 49% were positive by RSAT in controls. From 20 patients, gastric biopsy samples were taken, 11 patients were positive for H. pylori infection by gastric biopsy culture, 20 were positive by histopathological examination, and 13 were positive by rapid urea test. The salivary culture showed (100%) specificity, (38.5%) sensitivity, and (60%) accuracy. While PCR on saliva showed specificity (100%), (61.5%) sensitivity, and (75%) accuracy. RSAT showed (71.4%) specificity, 92.3% sensitivity, and 85% accuracy. Conclusion The oral cavity is an important extragastric reservoir of H. pylori; salivary PCR technique shows a much higher specificity and sensitivity than salivary culture. RSAT shows high sensitivity but with lower specificity.

Evaluation of Rapid stool antigen test for the diagnosis of Helicobacter pylori infection in patients with dyspepsia

Background and objectives: Several diagnostic assays are used for the detection of Helicobacter pylori infection in suspected peptic ulcer cases. H. pylori stool antigen test is a non-invasive method for the detection of active infection. The present study has evaluated the efficacy of rapid stool antigen test to diagnose H. pylori infection in patients with dyspepsia.Materials and methods: Adult patients with complains of dyspepsia attending the Department of Gastroenterology, Hepatobiliary and Pancreatic Diseases (GHPD) of BIRDEM hospital for endoscopy were included. Gastric biopsy, blood and stool samples were obtained from each participant after informed written consent. Rapid urease test (RUT), serum H. pylori immunoglobulin A (IgA) and IgG and rapid H. pylori stool antigen (HpSAg) tests were performed. Only stool samples were obtained from 31 neonates aged 1 to 30 days as negative control for HpSAg test.Results: A total of 91 adult patients with complain of dyspepsia were included in the study. Out of 91 cases, 17 (18.7%) and 74 (81.3%) had peptic ulcer and erosion respectively. HpSAg was positive in 63.7% cases compared to 42.9% and 62.6% respectively by RUT and IgA. The rate of HpSAg positivity was significantly higher (p<0.05) in ulcer compared to erosion cases. HpSAg test was positive in all (100%) RUT positive cases. Combination of HpSAg test and IgA yielded highest positive result in both ulcer (82.4%) and erosion (84%) cases. H. pylori IgG was positive in all cases.Conclusion: The study has demonstrated that HpSAg test is an effective and non-invasive diagnostic tool to detect active H. pylori infection in suspected dyspeptic patients.IMC J Med Sci 2016; 10(2): 39-44

Relation between Helicobacter pylori infection and severe pre-eclampsia complicated by intrauterine growth restriction in a rural area in Egypt

The purpose of this study was to evaluate the association of Helicobacter pylori (HP) infection with severe pre-eclampsia (PE) complicated by intrauterine growth restriction using rapid stool antigen test in a rural area in Egypt. Maternal stool samples were collected from 50 pregnant women diagnosed with PE-associated intrauterine growth restriction (IUGR) and from 50 women with healthy pregnancies (control) between 34 and 38 weeks of gestation. HP stool antigen (HPSA) was measured using a monoclonal antibody test, which is an immuno-chromatographic assay that uses antibody-coated colloidal gold. A significantly higher percentage of HPSA positive women were found among PE cases complicated by IUGR (76%) compared to healthy pregnancies (32%) (p < .0001). However, in the PE/IUGR group, neonatal weight was not significantly lower in HPSA positive patients compared to HPSA negative patients (p = .08). This led to our conclusion that Helicobacter pylori infection has a possible role in the etiopathogenesis of PE with IUGR with no evident effect on its severity.

Using different method for detection Helicobacter pylori that causing gastric cancer and compared with invasive method in the Al-Ramadi city

The study aims at finding out the most efficient method in the diagnosis and the easiest sample in usage. The study collects 50 samples from outpatients who customarily visit the medical sight unit. The collections of the samples include biopsy tissue, blood, saliva and stool from each patient, as well as 30 samples were collected from the control group (people who are not infected). The samples of biopsy tissue are used to test (Culture, rapid urease enzyme, and histopathology) through using saliva sample of the culture test. It also uses stool samples, rapid antigen stool test (strip) . However, the serum samples were used to detect antibodies formed IgG against infection with the Helicobacter pylori . The study compared between the invasive and non- invasive. the culture test was 6% of sensitivity and 100% of specificity, the rapid urease enzyme test was 66% of sensitivity and 90% of specificity and the histopathologic test was 14% of sensitivity and 100% of specificity. The rapid stool antigen test was 54% of sensitivity and 80% of specificity then the serum ELISA test with a sensitivity of 58% and specificity of 60%. It was found after comparing invasive with non-invasive methods that the rapid urease enzyme in invasive methods is the most efficient in diagnosis , also The non-invasive methods found the rapid stool antigen test the most efficient in diagnosis .

Applicability of a rapid stool antigen test, using monoclonal antibody to catalase, for the management of Helicobacter pylori infection

Most monoclonal antibody-based stool antigen tests are of the "send-out" format. Rapid Testmate pylori antigen (Rapid TPAg) uses monoclonal antibody and is an "in-the-office" test. The aim of this study was to examine the usefulness of Rapid TPAg for the management of H. pylori infection. One-hundred and two consecutive patients who received H. pylori eradication therapy underwent both urea breath test (UBT) and Rapid TPAg at 5-6 weeks after finishing the eradication therapy. Stool samples were maintained at -20, 5, 25, and 40°C and subjected to Rapid TPAg after 1-7 days. Stool samples were also tested by enzyme immunoassay (EIA) to quantify antigenicity. The agreement between Rapid TPAg and UBT in the evaluation of the results of H. pylori eradication treatment was 94.1%. The overall accuracy of Rapid TPAg and UBT to determine H. pylori eradication was 98.0 and 96.0%, respectively. The results of Rapid TPAg were not altered after storage of samples at -20 to 40°C for 7 days. Antigenicity quantified by EIA did not decrease significantly after 7 days. Rapid TPAg is a useful diagnostic test for immediate and accurate determination of the results of H. pylori eradication therapy. The antigenicity of stool sample suspensions was preserved for 7 days in the collection devices.

Validation of a rapid stool antigen test for diagnosis of Helicobacter pylori infection

The aim of this study was to validate the rapid lateral flow Helicobacter pylori stool antigen test (One step H. pylori antigen test, ACON laboratories, San Diego, USA; Prime diagnostics, São Paulo), using 13C-Urea Breath Test as the gold standard for H. pylori infection diagnosis. A total of 98 consecutive patients, asymptomatic or dyspeptic, entered the study. Sixty-nine were women, with a mean age of 45.76 +/- 14.59 years (14 to 79 years). In the H. pylori-positive group, the rapid stool antigen test detected H. pylori antigen in 44 of the 50 positive patients (sensitivity 88%; 95% CI: 75.7-95.5%), and six false-negative; and in the H. pylori-negative group 42 presented negative results (specificity 87.5%; 95% CI: 74.7-95.3%), and six false-positive, showing a substantial agreement (Kappa Index = 0.75; p < 0.0001; 95% CI: 0.6-0.9). Forty four of fifty patients that had positive stool antigen were H. pylori-positive, the PPV of the stool antigen test was 88% (95% CI: 75.7-95.5%), and 42 patients with negative stool antigen test were H. pylori-negative, the NPV of the stool antigen test was 87.5% (95% CI: 74.7-95.3%). We conclude that the lateral flow stool antigen test can be used as an alternative to breath test for H. pylori infection diagnosis especially in developing countries.

Rotavirus Infection in Small Bowel Transplant: A Histologic Comparison with Acute Cellular Rejection

Pediatric small bowel transplant recipients are susceptible to diarrhea due to rejection or infectious enteritis, particularly of viral etiology. The most common causes of viral enteritis in this setting are rotavirus, adenovirus, cytomegalovirus, and Epstein-Barr virus. This study is the first to compare the histologic findings of rotavirus infection with acute cellular rejection in small bowel transplant biopsies. Three patients with small bowel transplants had rapid stool antigen test-proven rotavirus infection. Endoscopic biopsies during infection were examined, including material from the allograft, native small bowel, stomach, and colon. Biopsies from 2 of the patients during unrelated episodes of mild acute cellular rejection were also evaluated. Blunting of villi was the most common finding in rotavirus infection. Additionally, there was a mononuclear infiltrate that was "top heavy," or denser towards the lumen. There were surface apoptoses but no increase in crypt apoptotic figures. In contrast, during mild acute cellular rejection, there was no villous blunting, the mononuclear infiltrate was diffuse, and there were increased crypt apoptosis. As expected, the changes of acute cellular rejection were confined to the graft, in contrast to rotavirus infection, in which case native bowel often had more pronounced changes. Although the small number of patients limits this study, several histologic features were helpful in identifying rotavirus infection. These were blunting of villi, distribution of the inflammatory infiltrate, number and location of apoptotic bodies, and anatomic location of the effect. A larger follow-up study would be valuable to confirm these findings.

Evaluation of a Rapid New Stool Antigen Test for Diagnosis of Helicobacter pylori Infection in Adult Patients

The evaluation of a new rapid stool antigen test showed different levels of sensitivity for final readings of test results at 20 min (59.1%) and 30 min (76.9%). Significant differences in performance were observed between the two sexes and the various age categories, with higher efficiency in male patients and young adults. Generally, this test is efficient and can be used to detect H. pylori infection in adults. However, further studies are required to confirm its accuracy.

Evaluation of a Novel Stool Native Catalase Antigen Test for Helicobacter pylori Infection in Asymptomatic North American Children

Rapid immunochromatographic tests for Helicobacter pylori infection have been developed to allow "near-patient" testing. We therefore performed a pilot study to test a rapid immunochromatographic stool antigen test for the diagnosis of H. pylori infection in asymptomatic children. We tested stool specimens collected from children participating in a cohort study in the United States and Mexico. H. pylori-positive status was defined by positivity on at least 2 tests: a commercial H. pylori stool antigen enzyme immunoassay, an immunoglobulin G antibody enzyme immunoassay, and the C-urea breath test. Negative H. pylori status was defined by negative findings of all of these tests. Of 52 children (22 girls, 30 boys) 25 were H. pylori-positive, 19 H. pylori-negative, and 8 uncertain (eg, presumably negative; positive findings on 1 of the 3 noninvasive tests). The sensitivity and specificity of the new stool antigen test for those with definite H. pylori status were 100% (exact 95% CI 86.3%-100% and 82.4%-100%, respectively). This rapid stool antigen test may prove useful for point-of-care testing and epidemiological field studies. Larger prospective studies are needed in symptomatic and asymptomatic children for more precise estimates.

Evaluation of 3 different tests for the detection of stool antigens to confirm Helicobacter pylori eradication after treatment. A pilot study

Introduction Recently, several new diagnostic methods aimed to detect Helicobacter pylori stool antigens have been developed. Our aim was to evaluate the accuracy of 3 different stool tests to confirm H. pylori eradication. Patients and methods Twenty-six patients received H. pylori eradication treatment. Eradication was confirmed with 13C-urea breath test 6-8 weeks later, when stool samples were analyzed by polyclonal (Premier-Platinum-HpSA™), monoclonal (Amplified-IDEIA™-HpStAR™), and rapid test (ImmunoCard-STAT-HpSA™). Results H. pylori was eradicated in 85% of the cases. Sensitivity, specificity, positive predictive value and negative predictive value with the polyclonal test were: 25%, 91%, 33% and 87%. Corresponding results with the monoclonal test, using the cut-off point recommended by the manufacturer, were 100%, 46%, 25% and 100%. However, the best cut-off point in our study had 100% sensitivity and 91% specificity. The area under ROC curve for the polyclonal and the monoclonal tests was 0.65 and 0.95. Diagnostic accuracy with the rapid test was 75%, 90%, 60% and 95%. Conclusion Neither the polyclonal stool antigen test nor the rapid stool antigen test can be recommended to confirm H. pylori eradication after treatment. The monoclonal test has better diagnostic accuracy, although more studies are necessary to definitively recommend its use for the confirmation of H. pylori eradication success.

Multicenter Comparison of Rapid Lateral Flow Stool Antigen Immunoassay and Stool Antigen Enzyme Immunoassay for the Diagnosis of Helicobacter pylori Infection in Children

The stool antigen enzyme immunoassay (EIA) methods are widely used for diagnosing Helicobacter pylori infection. Recently, a novel, rapid stool antigen test, the lateral flow immunoassay (LFI) method, has been developed. The primary purpose of this study was to compare the EIA method with the LFI method for the diagnosis of H. pylori infection in children. Stool specimens from children being evaluated for H. pylori infection were also examined using the LFI (ImmunoCard STAT! HpSA) and EIA methods (Premier Platinum HpSA). The sensitivity, specificity and accuracy of the test were based on the 13C-labeled urea breath test. One hundred and eighty-two children and adolescents, 3-17 years of age (mean 9.2 years), were studied. In addition, 29 patients who received eradication therapy were re-evaluated 2 or 3 months post-treatment. The 13C-labeled urea breath test was positive in 64 patients (35.2%). The sensitivity, specificity and accuracy of the LFI method were 90.6% (95% CI = 80.7-96.5%), 95.8% (92.1-99.4%), and 94.0% (90.5-97.4%), respectively and for the EIA method, sensitivity, specificity and accuracy were 96.8% (95% CI, 89.0-99.6%) and 99.2% (97.5-100%), and 98.3% (96.5-100%), respectively. There were no significant differences in results among the age groups 3-5, 6-10 and 11-17 years. As for the assessment of H. pylori eradication, the results of the LFI and EIA methods agreed with those of 13C-urea breath test in 27/29 and 29/29 patients, respectively. The LFI stool antigen method showed a good sensitivity, specificity and accuracy for diagnosing H. pylori infection in children. This novel method may be useful in clinical practice as an office-based test because it is rapid, reliable and easy to perform.

Evaluation of a rapid stoolantigen test for the diagnosis of Helicobacter pylori infection in Chinese patients

OBJECTIVE: To evaluate the accuracy of a rapid assay that wasdeveloped to detect Helicobacter pylori antigen in the stool,using the principle of immunochromatography, in the Chinese population.METHODS: Eligible patients without prior treatment of H.pylori were recruited. An in‐house rapid urease test (RUT) andhistology were used as the gold standard. The results of the rapidstool antigen test were compared with the gold standard.RESULTS: Valid rapid stool antigen test results for interpretationwere obtained from 94 consecutive patients (mean age: 52.5, range:22−82 years). Sensitivity, specificity, positive predictivevalue, negative predictive value and accuracy were, respectively, 77.5%,87.0%, 81.6%, 83.9% and 83.0%.The test was easy to perform and results were available within 15 min.CONCLUSION: The rapid stool antigen test using immunochromatography accuratelydiagnoses H. pylori infection in Chinese patients.