Journal of Mahatma Gandhi Institute of Medical Sciences (Jan 2019)

Prospective evaluation of the diagnostic performance of a new Helicobacter pylori stool antigen immunochromatographic test

  • Vikram Kate,
  • Mohsina Subair,
  • Ashok Kumar Sahoo,
  • Namrata Bhosale,
  • Madhuvanthi Karthikeyan,
  • Jharna Mandal,
  • Sathasivam Suresh Kumar,
  • Mahalakshmy Thulasingam

DOI
https://doi.org/10.4103/jmgims.jmgims_32_18
Journal volume & issue
Vol. 24, no. 1
pp. 23 – 27

Abstract

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Introduction: Stool-based immunochromatographic test (ICT) requires validation for use in regional setups. Hence, this study was carried out to evaluate the diagnostic performance of a newly developed ICT kit (Pylori-Strip/Pylori K-Set, Corisbio). Materials and Methods: This was a prospective analytical study on patients who underwent upper gastrointestinal endoscopy. The combination of histology and urease was used as gold standard. Stool specimens were subjected to immunochromatographic stool antigen test using Corisbio stool antigen kit. The diagnostic performance of cassette and dipstick method and combination both was compared to the gold standard. Correlation of test efficacy with endoscopic, histological, and demographic parameters was carried out. Results: A total of 143 patients were included in the study. The diagnostic performance of cassette method and dipstick method was sensitivity, 73.3% (22/30) and 73.3% (22/30); specificity, 97.3% (110/113) and 98.23% (111/113); positive predictive value (PPV), 88% (22/25) and 91.66% (22/24); negative predictive value (NPV), 93.22% (110/118) and 93.27% (111/119); and overall accuracy, 92.3% (132/143) and 93% (133/143), respectively, when compared with the gold standard. The combination of the tests had a sensitivity of 73.3% (22/30), specificity of 97.3% (110/113), PPV of 88% (22/25), NPV of 93.22% (110/118), and accuracy of 92.3% (132/143). The diagnostic performance of the kit was unaffected by various demographic, endoscopic, or histological characteristics. Conclusions: The stool-based ICT is rapid and noninvasive diagnostic test with a high specificity, PPV and NPV, and overall accuracy. However, as the sensitivity is low, it should be primarily used as a rapid office test to determine eradication of Helicobacter pylori.

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