Investigations

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MaagklachtenPublished by: NHGLast published: 2025

1st investigations to order

Helicobacter pylori urea breath test

Test
Result
Test

Current guidelines recommend patients with uninvestigated dyspepsia aged <60 years without alarm features suggestive of upper GI malignancy undergo non-invasive testing for H pylori.[3]​​

This test has >90% sensitivity and 96% specificity for presence of active infection.[44][46][47]​​

It can be used to monitor response to therapy.

Proton-pump inhibitors (PPIs), bismuth, antibiotics, and possibly potassium-competitive acid blockers (PCABs) can interfere with this test.[3][45] It is generally recommended that, in the post-treatment setting, PPIs and PCABs are withheld for 7-14 days and antibiotics and bismuth withheld for at least 28 days prior to use of the urea breath test to assess H pylori eradication.[3]​​

Result

positive in H pylori infection

Helicobacter pylori faecal antigen test

Test
Result
Test

A faecal antigen test identifies H pylori antigen in the stool to diagnose active infection.[22]

Both monoclonal and polyclonal assays are available, each with >90% sensitivity and specificity; monoclonal assay has a sensitivity of 96% and specificity of 97%.[48][49]

It can be used to monitor response to therapy.

Proton-pump inhibitors (PPIs), bismuth, antibiotics, and possibly potassium-competitive acid blockers (PCABs) can interfere with the test.[3][45] It is generally recommended that, in the post-treatment setting, PPIs and PCABs are withheld for 7-14 days and antibiotics and bismuth withheld for at least 28 days prior to use of the urea breath test to assess H pylori eradication.[3]​​

Result

positive in H pylori infection

FBC

Test
Result
Test

Phlegmonous gastritis may present with significant leukocytosis.[10][11][12][13]

Result

variable; may show reduced haemoglobin and haematocrit and increased mean cell volume in autoimmune gastritis; leukocytosis with left shift in phlegmonous gastritis

Investigations to consider

endoscopy

Test
Result
Test

The American College of Gastroenterology (ACG) and the Canadian Association of Gastroenterology (CAG) guidelines on dyspepsia recommend endoscopy for patients aged 60 years or older presenting with dyspepsia, and only on a case-by-case basis in younger patients with dyspepsia who have alarm features (weight loss, anaemia, dysphagia and persistent vomiting).[40]

The National Institute for Health and Care Excellence recommends same day referral to a specialist for any patient presenting with dyspepsia and significant gastrointestinal bleeding.[39]

Consider in patients with symptoms that are unresponsive to treatment.[39][40]

Patients with confirmed pernicious anaemia should undergo endoscopy to evaluate for any associated gastric malignancy.[41]

Endoscopy allows assessment of the gastric mucosa for alternative pathology and enables biopsy for histological assessment and testing for Helicobacter pylori infection (using tissue rapid urease testing and direct culture or molecular studies).[2]​​[40][41]

Proton-pump inhibitors (PPIs), bismuth, antibiotics, and possibly potassium-competitive acid blockers (PCABs) can interfere with the test.[3][45]​ It is generally recommended that, in the post-treatment setting, PPIs and PCABs are withheld for 7-14 days and antibiotics and bismuth withheld for at least 28 days prior to use of the urea breath test to assess H pylori eradication.[3]

Result

variable; evidence of gastric erosions and/or atrophy

Helicobacter pylori rapid urease test

Test
Result
Test

Can be performed on a single biopsy specimen from the antrum and a single biopsy specimen from the posterior corpus.[44]​ The tissue is placed in an agar gel or on a reaction strip containing urea, a buffer, and a pH-sensitive indicator. In the presence of H pylori urease, the urea is metabolised to ammonia and bicarbonate and detected as a colour change. This test has a 90% sensitivity and 100% specificity, as long as the patient does not have an acute gastrointestinal bleed and is not taking a proton-pump inhibitor (PPI) or an antibiotic.[46][47][50][51]

Result

positive in H pylori infection

gastric mucosal histology

Test
Result
Test

Provides histological diagnosis and classification of gastritis.

Use of Warthin-Starry silver stain has 93% sensitivity and 99% specificity for Helicobacter pylori.[46]

If the patient has an acute gastrointestinal bleed or is taking a proton-pump inhibitor (PPI) or an antibiotic, histological evaluation rather than H pylori rapid urease test is recommended.[51]

Result

variable; positive for H pylori; features of acute or chronic gastritis

serum vitamin B12

Test
Result
Test

Check in patients presenting with dyspeptic symptoms with signs and symptoms consistent with clinical vitamin B12 deficiency (e.g., unexplained neurological disease, depression/dementia, angular cheilitis, atrophic glossitis).[2][29][31]​ Check in patients with atrophic gastritis.[42]

This is most commonly due to chronic gastritis in older people and is also associated with autoimmune gastritis.[53]

Result

normal or low in autoimmune gastritis; findings of pernicious anaemia are indicative of late-stage autoimmune gastritis, and patients should undergo oesophagogastroduodenoscopy with biopsies to assess for neoplastic changes

upper gastrointestinal (GI) contrast series

Test
Result
Test

Less useful for diagnosis of gastritis.

Radiological confirmation may be obtained from a plain upper GI contrast series and/or CT of the abdomen.[10][11][12][13]

Result

presence of gas forming circular or linear collections along the gastric wall

blood/fluid cultures

Test
Result
Test

Recommended if phlegmonous gastritis is suspected.[10][11][12][13]

Cultures of blood and gastric aspirates are performed.

Result

positive for infectious agent

parietal cell antibodies

Test
Result
Test

Present in about 90% of patients with atrophic gastritis.[29]

Result

positive in autoimmune gastritis

intrinsic factor antibodies

Test
Result
Test

Highly sensitive for pernicious anaemia.[31]

Result

positive in autoimmune gastritis

Emerging tests

Helicobacter pylori culture/polymerase chain reaction (PCR)

Test
Result
Test

Can be performed on a single biopsy specimen from the antrum and a single biopsy specimen from the posterior corpus.[44]

High sensitivity and specificity for H pylori infection, although less sensitive than rapid urease testing.[46][47][50]

Limited availability; primarily used in research situations.

Result

positive in H pylori infection

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