|Values are valid only on day of printing.|
Screening for exposure to Helicobacter pylori
Helicobacter pylori is a spiral-shaped, gram-negative bacillus that has been associated with gastritis, gastric and duodenal ulcers, and gastric malignancies.
Helicobacter pylori is found worldwide. In Caucasian populations in the United States and other industrialized countries, Helicobacter pylori infection is infrequent in childhood. Prevalence increases 0.5% to 2% with each year of age, reaching about 50% in those who are 60 or older.(7) Prevalence rates appear to be higher in African American and Hispanics populations as compared to rates among Caucasians; this is thought to be due to socioeconomic status. In a random population of 200 apparently healthy blood donors tested for Helicobacter pylori IgG antibody, the positive rate was 27.5%.
The gold standard for diagnosis of Helicobacter pylori disease is gastric biopsy and evaluation for the presence of spirochetes by gram, silver, giemsa, or acridine orange stains. Alternatively, biopsied tissue can be examined by immunofluorescence or immunoperoxidase methods, rapid urease testing and/or culture.
Exposure to Helicobacter pylori can be determined by detection of IgA, IgG, or IgM-class serum antibodies to the organism. Screening patients for the presence of antibody to Helicobacter pylori is a convenient, noninvasive means for assessing whether a patient has been exposed to Helicobacter pylori and whether gastrointestinal symptoms may be related to Helicobacter pylori infection.
Because serology may lack specificity and does not distinguish between recent or remote infection, active disease is best diagnosed by the Helicobacter pylori stool antigen assay (HPSA / Helicobacter Pylori Antigen, Feces) or by the Helicobacter pylori urea breath test (UBT / Helicobacter pylori Breath Test).
See Helicobacter pylori Diagnostic Algorithm in Special Instructions
Negative (Results with index values of <8.95 are negative.)
Positive (Results with index values of > or =8.95 are positive.)
Negative (Results with index values of <36.00 are negative.)
Equivocal (Results with index values of > or =36.00 but < or =40.00 are equivocal.)
Positive (Results with index values of >40.00 are positive.)
Negative (Results with index value of <18.00 are negative.)
Equivocal (Results with index values of > or =18.00 but < or =20.00 are equivocal.)
Positive (Results with index values of >20.00 are positive.)
Patients with Helicobacter pylori infection nearly always develop IgG-class antibodies. However the presence of IgG-class antibodies does not distinguish between remote exposure to Helicobacter pylori and acute, ongoing infection. If clinically indicated, additional tests including either the urea breath test or the stool antigen assay should be performed to determine infection status.
This assay should be performed only on patients with gastrointestinal symptoms and should not be used to test asymptomatic patients.
A positive test result does not distinguish between colonization or infection by Helicobacter pylori and does not indicate the presence of gastrointestinal disease. It should be used as an aid to the detection of such disease with other clinical tests such as the urea breath test or stool antigen assay.
A negative result does not preclude the absence of antibodies to Helicobacter pylori. Colonization may be present, however it may be in its very early stages or the antibody titer may be too low for the assay to detect.
1. Blaser MJ: Helicobacter pylori and related organisms. In Principles and Practice of Infectious Diseases. Vol 2. Fourth edition. Edited by GL Mandell, R Dolin, JE Bennett. Churchill Livingstone Inc., 1995, pp 156-164
2. Perez-Perez GI, Taylor DN, Bodhidatta L, et al: Seroprevalence of Helicobacter pylori infections in Thailand. J Infect Dis 1990;29:2139-2143
3. Drumm B, Perez-Perez GI, Blaser MJ, et al: Intrafamilial clustering of Helicobacter pylori infection. N Engl J Med 1990;322:359-363
4. Morris AJ, Ali MR, Nicholson GI, et al: Long term follow-up of voluntary ingestion of Helicobacter pylori. Ann Intern Med 1991;114:662-663
5. Evans DJ Jr, Evans DG, Graham DY, et al: A sensitive and specific serologic test for detection of Campylobacter pylori infection. Gastroenterology 1989;96:1004-1008
6. Glassman MS, Dallal S, Berezin SH, et al: Helicobacter pylori related gastroduodenal disease in children. Diagnostic utility of enzyme-linked immunosorbent assay (ELISA). Dig Dis Sci 1990;35:993-997
7. Couturier MR: The evolving challenges of Helicobacter pylori disease, diagnostics, and treatment, part 1. Clinical Microbiology Newsletter 2013;35(3):19-23