No evidence that stool test is more accurate than blood test for stomach ulcer diagnosis
Helicobacter pylori (H pylori) is a bacteria frequently present in the stomach of some people, and can cause stomach, pancreatic and throat cancer. Infection with H pylori is also associated with other gastrointestinal diseases including bloating, stomach ulcers and heartburn. Once diagnosed, an infection with H pylori can be treated with a combination of antibiotics.
A recent Cochrane review of the accuracy of three common methods for diagnosis of H pylori infection (1) comprised 101 studies with over 11,000 participants where over half had an H pylori infection.
The authors concluded that in patients who had not recently received antibiotics or proton pump inhibitors (PPI), the urea breath test had the highest accuracy. For every 1000 people, the blood test (serology) will give 86 false negatives, and the stool antigen test 89 false negatives.
A more recent study investigating the accuracy of serology, stool antigen and urea breath test for the initial diagnosis of H pylori gastritis in 2,560 patients (2) showed that blood tests that detect H pylori IgG antibodies had a higher sensitivity (94%) than both the urea breath test (64%) and the stool antigen test (61%).
In summary, further studies of high methodological quality are required to establish the relative accuracy of tests for H pylori infection.
- Best LMJ, Takwoingi Y, Siddique S, Selladurai A, Gandhi A, Low B, Yaghoobi M, Gurusamy K. Non-invasive diagnostic tests for infection. Cochrane Database of Systematic Reviews 2018, Issue 3. Art. No.: CD012080.
- Bosch DE, Krumm N, Wener MH, Yeh MM, Truong CD, Reddi DM, Liu Y, Swanson PE, Schmidt RA, Bryan A. Serology Is More Sensitive Than Urea Breath Test or Stool Antigen for the Initial Diagnosis of Helicobacter pylori Gastritis When Compared With Histopathology. Am J Clin Pathol. 2020 Jul 7;154(2):255-265.
The SELFCHECK Stomach Ulcer Test is a simple and convenient, finger-prick blood spot test that detects H pylori antibodies, with a reliable result in 10 minutes at home. For further information see selfcheckmedical.com