Anti Extractable Nuclear Antigens (ENA) Blood Test
Test Code: 006338
Specimen Type: Blood
Anti Extractable Nuclear Antigens (ENA) Test (Labcorp)
The Extractable Nuclear Antigen (ENA) test looks for the presence of 2 types of autoantibodies. Autoantibodies are produced by the body's immune system and mistakenly attack its own cells and tissues. Different types of ENA markers are associated with certain types of autoimmune disorders. This test looks for both Smith (Sm) Antibodies and Anti-Ribonucleoprotein (RNP). ENA testing is usually done as a followup to a Positive Antinuclear Antibody (ANA) test, especially when a person has symptoms of an autoimmune disorder. Common autoimmune disorders symptoms include fever, chronic fatigue, muscle pain, joint swelling, rash, hair loss, sensitivity to sunlight, anemia with low RBC or WBC counts, depression, and seizures. The type of autoantibodies that are present can help make a diagnosis and differentiate between different autoimmune disorders.
- Anti-SMith: Anti-SM is specific to Lupus. However, only about a third of Lupus cases will have positive smith antibodies.
- Anti-RNP: RNP is positive for almost all cases of Mixed Connective Tissue Disease (MCTF). It may also be positive in some cases of Lupus and scleroderma.
Other common autoantibody tests which are often done at the same time include Sjogren Anti SSA & SSB test and Anti-Jo-1.
Turnaround for this test is typically 2-3 business days.
Where can I find an Anti Extractable Nuclear Antigens (ENA) test near me?
Check our lab finder to locate a collection site in your area.
Note: Result turn around times are an estimate and are not guaranteed. Our reference lab may need additional time due to weather, holidays, confirmation/repeat testing, or equipment maintenance.