ImmunoCAP Specific IgA measures antigen-specific IgA antibodies in human serum and plasma. Specific IgA antibodies are part of the body’s immune system. They are present in secretions such as saliva and mucosa, as well as in the blood. High levels of specific IgA antibodies in serum to food antigens may indicate increased exposure caused by damage to the intestinal mucosa. In celiac disease, for example, the levels of specific IgA antibodies to gliadin are important for diagnosis.
Monitoring elevated levels of antigen-specific IgA antibodies in serum may help manage problems related to food, especially food-sensitive enteropathies in children. IgA antibodies may also be an indicator of tolerance development.
Expected test values
There are no recommended cut-off values for specific IgA antibodies in general as they are markers for antigen exposure and are not directly related to a disease. Results vary both within and between antigens. Geographical variations are also important, as are individual levels of exposure.
To determine if levels are increased, the reference level of specific IgA antibodies to a certain antigen must be measured in a number of samples from normal healthy individuals and, if possible, compared with the levels in a group of patients.
As in all diagnostic testing, a definitive clinical diagnosis should not be based solely on the results of a single test method. A diagnosis should be made by the physician after evaluation of all clinical and laboratory findings.