The immunoglobulin A (IgA) blood test is a test that measures the level of IgA in the blood. IgA is a type of antibody that is primarily found in the mucous membranes of the body, such as those in the respiratory and digestive tracts, as well as in saliva and tears.

The IgA blood test is usually ordered as part of a panel of tests used to evaluate immune system function. Elevated levels of IgA may be indicative of certain infections or autoimmune diseases, such as celiac disease or IgA nephropathy. Low levels of IgA can also occur in some individuals with a genetic condition called selective IgA deficiency, which increases the risk of infections, allergies, and autoimmune diseases.

The test is performed by taking a blood sample from a vein in the arm, and then measuring the levels of IgA in the blood. Interpretation of the test results should be done in consultation with a healthcare provider who can interpret the results in the context of the individual’s symptoms, medical history, and other test results.

In summary, the IgA blood test is a test that measures the level of IgA in the blood. Elevated levels of IgA may be indicative of certain infections or autoimmune diseases, while low levels of IgA can occur in some individuals with a genetic condition called selective IgA deficiency. Interpretation of the test results should be done in consultation with a healthcare provider.