The purpose of a diagnostic antinuclear antibody test is to rule out specific rheumatic or autoimmune diseases by detecting the presence of nuclear antibodies in the blood, explains Mayo Clinic. Typically, antibodies work to protect the body against infection, but antinuclear antibodies target the nuclei of cells and attack the body's tissues.
This type of diagnostic test does not specifically diagnose particular conditions or diseases, according to Mayo Clinic. Instead, a positive test result indicates the need for further testing. Some people with positive test results are healthy. However, for those who have disorders, additional testing pinpoints the specific type of antinuclear antibodies present in their bodies. Particular antibodies are specific to certain types of diseases. A person who has an autoimmune disease has antibodies that attach to the body's healthy cells, which typically occurs when a foreign bacterial or viral infection is present. This causes the destruction and damage of healthy tissues, notes WebMD.
Some issues that may affect the results of an antinuclear antibody test include taking medications for high blood pressure, tuberculosis and heart disease, as well as a viral illness, reports WebMD. Particular types of autoimmune diseases of the connective tissue include lupus, rheumatoid arthritis, polymyositis, Raynaud's syndrome and scleroderma. Autoimmune disorders of organs include Addison's disease, hemolytic anemia, thyroid disease and liver diseases such as hepatitis.