Question: What is an antinuclear antibodies (ANA) test and how is it used to diagnose rheumatoid arthritis?
Answer: The immune system is there to stop invaders. So, basically, if we get an infection, the immune system works like a Star Wars and kills the invader. Unfortunately, in some people, related to genetic pre-disposition and various triggers in the environment, the immune system can work against self and that's called autoimmunity. There are specific types of autoantibodies that can be found in people with various types of arthritis.
For example, in systemic lupus erythematosus, which is an illness of young women mostly, who have many inflammatory problems such as arthritis, kidney disease, brain problems and skin rash, they have significant amount of auto antibodies called antinuclear antibodies. The reasons they are called that is because on special tests in the laboratory, these specific antibodies target the nucleus of the cell.
In some people with rheumatoid arthritis, they also have antinuclear antibodies. It's important to note that in rheumatoid arthritis, that the most prominent autoantibodies are rheumatoid factors and anti-CCP antibodies. And the presence of those bode for more severe disease and potential damage, unless the illness is controlled by new medicines.
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