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    Helicobacter Pylori Tests


    Helicobacter pylori tests are used to detect a Helicobacter pyloriHelicobacter pylori (H. pylori) infection in the stomach and upper part of the small intestine (duodenum).

    Results from the urea breath test or a stool antigen test are usually available within a few hours. Results from a blood antibody test are usually available within 24 hours. Results from biopsy samples obtained by endoscopy are usually available within 48 hours. Results from a biopsy sample that is cultured can take up to 10 days.

    Blood antibody test

    The blood sample does not contain H. pylori antibodies.


    The blood sample contains H. pylori antibodies.

    Urea breath test

    The breath sample does not contain the tagged carbon dioxide.


    The breath sample contains the tagged carbon dioxide.

    Stool antigen test

    The stool sample does not contain H. pylori antigens.


    The stool sample contains H. pylori antigens.

    Stomach biopsy

    The biopsy sample camera.gif does not contain H. pylori bacteria.

    H. pylori bacteria does not grow in a culture of the tissue biopsy samples.


    The biopsy sample contains H. pylori bacteria.

    H. pylori bacteria grows in a culture of the tissue biopsy samples.

    What Affects the Test

    Reasons you may not be able to have the test or why the results may not be helpful include the following:

    • Most urea breath tests now use tagged carbon rather than radioactive carbon. If you are pregnant, the radioactive urea breath test for H. pylori is not usually done, because the radiation could harm your child.
    • Use of antibiotics may affect the results of the urea breath test, the stool antigen test, and stomach biopsy by reducing the number of H. pylori bacteria in the stomach and duodenum camera.gif.
    • The use of cimetidine (Tagamet), famotidine (Pepcid), lansoprazole (Prevacid), nizatidine (Axid), omeprazole (Prilosec), rabeprazole (Aciphex), ranitidine (Zantac), sucralfate (Carafate), or medicines containing bismuth (such as Pepto-Bismol) can also interfere with the results of the urea breath test, the stool antigen test, and stomach biopsy.
    • A stomach biopsy may not detect an H. pylori infection that is present if the biopsy samples are taken from areas that are not infected by the H. pylori bacteria.
    • Rough handling, contamination, or inadequate refrigeration of the blood sample can cause inaccurate blood antibody test results.
    • When a blood antibody test is done early in an H. pylori infection, the results may be falsely negative because the level of antibodies is too low to measure.
    • The likelihood of infection with H. pylori increases with age. Older adults are more likely to have detectable amounts of the bacteria in their body.
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    WebMD Medical Reference from Healthwise

    Last Updated: November 14, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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