Helicobacter pylori

Helicobacter pylori (H. pylori), previously known as Campylobacter pylori, is one of the most common bacterial pathogens in humans; over half of the world’s population is infected.  Approximately 35% of the U.S. population is infected,  with the highest prevalence in those with lower socioeconomic status, older age, and non-Caucasian ethnicity. Diagnostic testing can be divided into two categories: noninvasive (urea breath testing and stool antigen testing) and invasive (biopsy-based testing). For most patients with a low risk of gastric cancer, the test-and-treat strategy using noninvasive diagnostic testing is appropriate. In these cases, the choice of a urea breath test or stool antigen test can be based on availability, cost, and acceptability, as both options are highly sensitive and specific for detecting persistent H. pylori infection.  These same tests can also be used to evaluate the success of therapy.

Quick Answers for Clinicians

Who should be tested for Helicobacter pylori (H. pylori) infection?

Patients who present with predominant epigastric pain lasting at least 1 month may be considered for Helicobacter pylori (H. pylori) testing.   The American College of Gastroenterology  specifically recommends testing in individuals with active peptic ulcer disease (PUD), a history of PUD, or uninvestigated dyspepsia and in those initiating chronic treatment with a nonsteroidal anti-inflammatory drug.

Are there noninvasive testing strategies for diagnosing Helicobacter pylori (H. pylori) infection?

Yes. The urea breath test or the stool antigen test are the two noninvasive methods for the diagnosis of Helicobacter pylori (H. pylori) infection, and both are equally appropriate for adult patients younger than 60 years and without alarm symptoms.  See Laboratory Testing below.

What are the advantages/disadvantages of the different noninvasive test methods?

Both the urea breath test and the stool antigen test have good positive and negative predictive value for diagnosing Helicobacter pylori (H. pylori) infection. Neither test requires an endoscopy or biopsy specimen; however, stool collection or consumption of a urea-containing capsule or solution may be undesirable for some patients.

Is serologic testing useful for diagnosing Helicobacter pylori (H. pylori) infection?

Serology is not recommended for the diagnosis of Helicobacter pylori (H. pylori) infection.    ,  Serologic testing, whether for immunoglobulin (Ig) G (IgG), IgM, or IgA, cannot accurately detect active infection, as antibodies may remain long after successful treatment.  Serology is also less sensitive and specific than either the urea breath test or the stool antigen test.

Which testing algorithms are related to this topic?

Indications for Testing

Testing is used to diagnose H. pylori infection and evaluate treatment success. Screening asymptomatic patients in the general population is not recommended. 

Laboratory Testing


The decision to use noninvasive or invasive test methods for diagnosis of H. pylori infection is dependent on the age of the patient and whether the patient presents with alarm symptoms (gastrointestinal bleeding, unexplained iron deficiency anemia, early satiety, unexplained weight loss, progressive dysphagia, odynophagia, recurrent vomiting, family history of gastrointestinal cancer, and previous esophagogastric malignancy).  Noninvasive testing using either the urea breath test or the stool antigen test is indicated for adults younger than 60 years of age who present without alarm symptoms. Invasive testing methods involving endoscopy and biopsy are indicated for children, adults who are 60 years or older, and those who present with alarm symptoms.    Noninvasive testing may be acceptable for children when evaluating causes of chronic immune thrombocytopenic purpura or when a false-negative invasive test result is suspected.  For accurate results, it is recommended that patients stop use of proton-pump inhibitors (PPIs) for 2 weeks before any H. pylori testing. Histamine 2-receptor antagonists may reduce urease activity on urea breath tests and should be discontinued 24-48 hours before the sample is collected.

Noninvasive Testing

Urea Breath Test

The 13C-urea breath test is considered the best noninvasive approach for the diagnosis of active H. pylori infection.  Testing requires the patient to fast and abstain from smoking for 1 hour before testing. Achlorhydria or urease-positive organisms other than H. pylori in the gut may increase the risk of a false-positive result.

Stool Antigen

The stool antigen test uses an enzyme immunoassay to detect H. pylori antigen in stool. Its ability to detect infection is equal to that of the urea breath test. 

Invasive Testing

Invasive testing strategies require upper endoscopy with biopsy. Biopsy of the antrum is recommended at a minimum,  but biopsy of additional areas (eg, the corpus) may improve diagnostic utility and is recommended in children.  Biopsy-based tests are less sensitive when performed during active gastrointestinal bleeding; if a false-negative result is suspected, noninvasive testing may be considered.  

Rapid Urease

When endoscopy is indicated and there is no contraindication for biopsy, the rapid urease test is recommended as a first-line diagnostic test ; it is accurate and inexpensive and allows for immediate treatment.   The rapid urease test is highly sensitive but not always specific for H. pylori, as other urease-positive organisms in the gut may cause a false-positive result.  Additionally, because active gastrointestinal bleeding decreases the sensitivity of urease-based tests, histology may be preferable.  In patients who have not recently used PPIs and antibiotics, the rapid urease test may be preferred over histology. 

Histology (With or Without Staining)

The sensitivity of histology in detecting H. pylori is subject to the area being sampled and the number of samples, but the addition of stains (eg, Giemsa, Warthin-Starry, hematoxylin and eosin, immunohistochemistry) may increase the sensitivity.  Histologic evaluation has the added value of potentially uncovering an unsuspected pathology, such as inflammation, metaplasia, dysplasia, and malignant neoplasm.  Although PPIs and antibiotics can interfere with bacterial density, histology is better for patients who have recently used these medications.  In children, histology should be performed in addition to another biopsy-based test. 


Although highly specific (100%),  culture is less sensitive than either the rapid urease test or histology  and has the disadvantage of requiring a 2-week incubation period that may or may not yield successfully growing colonies.   However, it is recommended in children and can be used as the sole test for diagnosis in this patient group.  An additional benefit of culture is that it enables antibiotic susceptibility testing.  


Follow-up testing after treatment using either the urea breath test or stool antigen test is recommended in both children and adults. This should occur no sooner than 4 weeks after completion of antibiotic therapy and after PPI therapy has been suspended for 1-2 weeks.    Biopsy-based testing may also be performed in adults when a repeat endoscopy is needed.  Because all tests are highly sensitive and specific, the choice of which test to use can be based on patient needs and preferences.  However, the rapid urease test is not recommended by some  for evaluation of eradication after treatment.

ARUP Lab Tests

Noninvasive Tests

Diagnose H. pylori infection in adults

Use to confirm eradication of H. pylori at least 4 weeks following completion of therapy

Do not order for children <18 years

Aliases: 13C-urea breath test, urea breath test

Confirm eradication of H. pylori in patients 3-17 years of age who are diagnosed by endoscopy and appropriately treated

Aliases: 13C-urea breath test, urea breath test

Diagnose H. pylori infection (an alternative to the urea breath test)

Use to confirm eradication of H. pylori at least 4 weeks following completion of therapy

Less accurate in pediatric patients

Invasive Tests

Aid in histologic diagnosis of H. pylori

Stained and returned to client pathologist; consultation available if needed

Consider for diagnosis of H. pylori infection in children or for susceptibility testing in patients with treatment failure

Cultures positive for H. pylori will be sent for susceptibility testing to Mayo Medical Lab

Medical Experts



Jenna Rychert, PhD, ABMM
Adjunct Assistant Professor of Clinical Pathology, University of Utah
Medical Director, Microbial Immunology, ARUP Laboratories


Marc Roger Couturier, PhD, D(ABMM)
Associate Professor of Clinical Pathology, University of Utah
Medical Director, Parasitology/Fecal Testing, Infectious Disease Antigen Testing, Bacteriology, and Molecular Amplified Detection, ARUP Laboratories


Jonathan R. Genzen, MD, PhD
Associate Professor of Clinical Pathology, University of Utah
Chief Operations Officer, Medical Director of Automated Core Laboratory and Farmington Health Center Clinical Laboratory, ARUP Laboratories


Additional Resources