Accuracy of H. pylori fecal antigen test using fecal immunochemical test (FIT)

Abstract

Background Gastric and colorectal cancer (CRC) are both one of the most common cancers worldwide. In many countries fecal immunochemical tests (FIT)-based CRC screening has been implemented. We investigated if FIT can also be applied for detection of H. pylori, the main risk factor for gastric cancer. Methods This prospective study included participants over 18 years of age referred for urea breath test (UBT). Patients were excluded if they had used antibiotics/bismuth in the past 4 weeks, or a proton pomp inhibitor (PPI) in the past 2 weeks. Participants underwent UBT, ELISA stool antigen test in standard feces tube (SAT), ELISA stool antigen test in FIT tube (Hp-FIT), and blood sampling, and completed a questionnaire on user friendliness. UBT results were used as reference. Results A total of 182 patients were included (37.4% male, median age 52.4 years (IQR 22.4)). Of these, 60 (33.0%) tested H. pylori positive. SAT and Hp-FIT showed comparable overall accuracy 71.1% (95%CI 63.2–78.3) vs. 77.6% (95%CI 70.4–83.8), respectively (p = 0.97). Sensitivity of SAT was 91.8% (95%CI 80.4–97.7) versus 94.2% (95%CI 84.1–98.9) of Hp-FIT (p = 0.98). Serology scored low with an overall accuracy of 49.7% (95%CI 41.7–57.7). Hp-FIT showed the highest overall user convenience. Conclusions FIT can be used with high accuracy and sensitivity for diagnosis of H. pylori and is rated as the most convenient test. Non-invasive Hp-FIT test is highly promising for combined upper and lower gastrointestinal (pre-) cancerous screening. Further research should investigate the clinical implications, benefits and cost-effectiveness of such an approach.

The use of non‐invasive stool tests for verification of Helicobacter pylori eradication and clarithromycin resistance

“…Rt-PCR results were in 100% concordance with culture results from these six patients, with three cases of clarithromycin resistance and three cases of clarithromycin-susceptible H. pylori. 18 In this followup study we show that H. pylori antigen testing in traditional stool and FIT performs equally well for the verification of eradication of H.…”

“…We have previously shown that the non‐invasive stool antigen test (SAT), which detects H. pylori antigen in fecal matter, is as efficient for the diagnosis of H. pylori infection as the urea breath test (UBT). This study also showed that patients are more comfortable collecting fecal immunohistochemical test (FIT) samples than solid fecal material 18 and that fluid collected from FIT tests was equally effective for H. pylori stool antigen detection as solid stool samples.…”

“…Overall, SAT in stool or FIT showed lower specificity for the detection of eradication than previously reported for H. pylori diagnosis. 18 We hypothesized that this might be due to trace amounts of H. pylori antigen still being present in the stool after eradication.…”

DNA starvation/stationary phase protection protein of Helicobacter pylori as a potential immunodominant antigen for infection detection

“…SAT has been favored in recent years due to its advantages of convenient operation and independent of expensive equipment 28 . Although the sensitivity and specificity of some commercial products have achieved comparable results to the urea breath test in scientific research, 29–33 there is still a lack of large‐scale population test data to support it. It can only be used as a supplement to the urea breath test at present, and cannot completely replace the breath test.…”

“…SAT has been favored in recent years due to its advantages of convenient operation and independent of expensive equipment. 28 Although the sensitivity and specificity of some commercial products have achieved comparable results to the urea breath test in scientific research, [29][30][31][32][33] there is still a lack of large-scale popula- To develop a high-sensitivity, high-specificity stool antigen detection kit, one or several specific antigens that can be used as detection targets must first be screened out. These antigens should have high protein abundance in most or all H. pylori strains, their protein sequences should be conserved in H. pylori, at the same time, the sequence similarity with homologous proteins in other intestinal flora should be low, so as to ensure a wide range of H. pylori strain coverage and the specificity of the detection.…”