A physician will order an Antinuclear Antibody (ANA) titer in order to check for autoimmune diseases. These are diseases in which the immune system in the body starts to attack the healthy cells of the host. The most common autoimmune disease that ANA titers test for is systemic lupus erythematosus (SLE). This disease is characterized by arthritis, a rash and a decrease in the number of platelets in the blood. The ANA titer can indicate other diseases as well, depending on how the antibodies appear under the microscope.
Check to see if the titers are increased, such as 1:320. This indicates that there are antibodies present and that the test is positive. If the number is low, then the test is negative and it is less likely that an autoimmune disease is present.
Check to see if the pattern associated with the titer is homogenous (diffuse). This pattern can indicate a diagnosis of systemic lupus erythematosus or mixed connective tissue disease.
Check to see if the pattern reported is speckled. This pattern is associated with SLE, Sjogren's syndrome, scleroderma, polymyositis, rheumatoid arthritis, and mixed connective tissue disease.
Check to see if the reported pattern is nucleolar. This is associated with sclerodema and polymysitis.
Check to see if the associated pattern is centromere (peripheral). This pattern can indicate scleroderma or CREST which stands for Calcinosis, Raynaud's syndrome, Esophogeal dysmotility, Sclerodactyly, and Telangiectasia.