No, sometimes serum anti-gliadin antibodies may be high while stool anti-gliadin antibodies may be normal, or vice versa.
There are different concentrations and types of gliadin antibodies present in serum and stool. IgG antibodies reflect about 80% of the total immunoglobulin pool, whereas IgA antibodies reflect about 15% of the total immunoglobulin pool, with the remaining 5% as IgE, IgM, and IgD antibodies. IgD antibodies are typically co-expressed with IgM antibodies, account for <1% of the antibody pool, and are rarely measured in clinical health sciences.
The Gut Zoomer measures IgA anti-gliadin antibodies.
The Wheat Zoomer measures several IgA and IgG gliadin antibodies (alpha-, alpha-beta-, gamma-, and omega-gliadin).
Sometimes, both serum and stool anti-gliadin antibodies will be elevated; this may reflect more advanced or longer term prevalence of gluten sensitivity.
Sometimes, serum anti-gliadin IgG antibodies will be elevated, but stool anti-gliadin IgA antibodies are normal. This may reflect a recent decrease in gluten consumption or may reflect sub-clinically low IgA antibodies. In this scenario, a Total Immunoglobulins panel should be considered for clinical reasoning and decision making.
Sometimes stool anti-gliadin IgA antibodies will be elevated, but serum anti-gliadin IgA antibodies will be normal. This may reflect recent intake in gluten on an otherwise longer term gluten restricted or gluten free diet, early gluten sensitization in the gut that is not yet systemic or long term, or more systemic immunosuppression resulting in false low serum IgA antibodies. In this scenario, a Total Immunoglobulins panel should be considered for clinical reasoning and decision making.