The immune system's function in the body is to fight infection by producing antibodies against the invading foreign bodies - microbes and other foreign substances. When the immune system becomes defective, it produces antibodies against the body's own cells. Anti-nuclear antibodies (ANA) are produced against the nucleus of a cell, leading to tissue and organ damage. An ANA test is recommended when an autoimmune disorder is suspected.
Why the test is done?
An ANA test is mainly useful in determining the presence of autoimmune disorders in a patient's body affecting different parts of the body. The test may also be recommended to help diagnose systemic lupus erythematosus (SLE).
When is the test ordered?
An ANA test may be ordered when a physician suspects that the signs and symptoms shown by a patient are due to an autoimmune disorder. Such signs and symptoms are-
Pain in the joints
Skin sensitivity to light
Inflammation in internal organs include lungs, heart, blood vessels and central nervous system.
How is the sample collected?
A blood sample is collected from a vein in the arm.
How to prepare for the test?
No special preparations are required for this test.