H-Pylori is a bacteria responsible for one of the most common infections found in humans worldwide. It is associated with MALT lymphoma. Importantly, when associated with MALT, eradication of the infection can cause the lymphoma to resolve.
"Helicobacter pylori has been claimed to be an important aetiological (causative) factor which raises the risk of mucosa-associated tissue lymphoid (MALT) lymphoma. However, some studies on gastric MALT lymphoma revealed a low rate of H. pylori infection suggesting that not all gastric lymphomas are related to H. pylori infection." 6
TESTS:
- Serologic assay of anti-HP immunoglobulin G
- Urea breath test
- Antigens in feces
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Biopsies from endoscopy, followed by:
- Histologic examination of gastric tissue
- Rapid urease testing (CLO-test)
- Culture of organisms
- Cytological analysis
- PCR testing to identify H-pylori DNA 7
To avoid false-negative test results: Avoid antibiotics, bismuth compounds, or PPIs 2 weeks prior to tests.3
"Serologic testing and endoscopy are clearly the most inexpensive and expensive methods, respectively, for diagnosing infection in an untreated patient.
Selection of the appropriate test for a patient is dependent upon the clinical situation.
With all diagnostic tests except serologic assays, a particularly important consideration is the potential for false-negative results in patients who have taken antibiotics, bismuth compounds, or proton pump inhibitor (PPI) acid suppression in the past 1 to 2 weeks." 3
Also see Endoscopy - About Cancer Help Org | Medline Plus
References
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Randomized trial of endoscopy with testing for Helicobacter pylori compared with non-invasive H pylori testing alone in the management of dyspeps - bmj.bmjjournals.com
Conclusion: In this patient group, non-invasive testing (Breath Test) for H pylori is as effective and safe as endoscopy and less uncomfortable and distressing for the patient. Non-invasive H pylori testing should be the preferred mode of investigation.
Note: But endoscopy might be most appropriate when also diagnosing for MALT.
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H.Pylori Home Test Kit-(commercial) - equiptrip.com
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Improving H-Pylori Therapy - pec.ha.osd.pdf
(Includes information about how to avoid false-negatives.)
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H-Pylori tests - clin-path.com/html/newsletters/pdfs/August2000.PDF
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Which test to use to detect Helicobacter pylori infection in patients with low-grade gastric mucosa-associated lymphoid tissue lymphoma? Am J Gastroenterol. 2003 Feb;98(2):291-5. PMID: 12591043
Because gastric MALT lymphoma is a rare disease, few studies comparing the accuracy of diagnostic tests in this group of patients have been carried out, and only a limited number of tests (essentially histological) were performed.
The aim of our study was to compare the results of four different diagnostic methods used to detect H. pylori (histology, culture, polymerase chain reaction, and serology) in a prospective multicenter study.
A patient was considered to be H. pylori positive if culture or histology was positive.
During the period 1995-2000, a total of 90 patients with low-grade gastric MALT lymphoma were enrolled.
Results for the four tests were available for 56 patients (62.2%). Among these patients:
the four tests were concordant in 35 cases (62.5%),
i.e., were positive in 19 cases (33.9%) and negative in 16 patients (17.8%).
Histology (39/40 positive, 97.5%) and serology (38/40 positive, 95.0%) were the most sensitive tests.
Polymerase chain reaction (PCR) and culture were positive in 52.5% and 50%, respectively.
The cagA gene was detected in 47.4% of the strains.
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The role of Helicobacter pylori in primary gastric MALT lymphoma.
Histopathology. 1999 Feb;34(2):118-23. PMID: 10064390
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About H-pylori - emedicine
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