Lupus Guide for the Perplexed: ANA testing

I have a strange reaction to bad news.  I want to laugh at it, in the most savage, sarcastic and brutal way possible.  I know it's an odd response to tragedy, but for some reason it helps me keep things in perspective and keeps me from going insane.  So, with all this auto-immune disease stupidity I'm going through, I think I'll make fun of that, too. 

In the interest of giving people some basic information on what the SLE testing process is like, and in the interest of me not going insane, I've decided to kill two birds with one stone and do a series on lupus vocabulary.  The information is all culled from legit government and academic sources, although a little...  strange.  This is the first installment, and I hope you enjoy it!

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ANA (Anti-nuclear antibody): 

In layman's terms, this is a blood test to determine your body's level of misdirected hatred and self-loathing, and could just as well be termed your Immunological Emo Factor; it's just a way to see if your white blood cells have a Flock of Seagulls haircut or listen to Snow Patrol on their itty-bitty little iPods.

To be serious, an ANA is a serum-based screening method that's designed to check for signs of your immune system attacking normal cells instead of, you know, diseases and stuff.  A lab technician puts some of your serum in a petri dish with some cells to see what happens.  If everybody holds hands and sings protest songs, then it's negative.  If World War III in a microcosm breaks out, then it's positive.   The presence of antibodies that go after the nucleic matter in cells is an indication that something is rotten in the state of your autoimmune Denmark, telling your doctor that it's time to look further and see why everybody's so angsty all of a sudden. 

This test can have  a variety of different 'positive' readings that can be helpful to point your doctor to possible diagnoses, but it's not by any means going to tell you if you have SLE; a positive result on an ANA can indicate everything from other autoimmune diseases to cancer to absolutely nothing.  This is simply the version of your immunological "check engine" light going off.  If it's blinking, then maybe you've blown a head gasket.  It's much more likely that your gas cap is loose.

How important is a positive ANA to being diagnosed with lupus?  Sort of.  Depending on whom you ask, 95-97% of lupus sufferers will eventually have a positive ANA.  (And there's literature trying to figure out what's up with that other 5%.)  The ANA doesn't mean you have lupus, but it is the first line of attack doctors will use to determine whether or not to start worrying about it. 

So, if a doctor, like a good car mechanic, suspects lupus, this is often the first place they'll check because there is no reason to run more specific antibody tests until this one shows that there's a problem.  But, just because you get a negative result on your first ANA doesn't mean you won't pop positive later-- so it's important to have your ANA run several times, over several years, and make sure that all come back negative before you stick a stake in the heart of your autoimmune vampire.  He might still be lurking, with his Emo haircut and black lipstick, to show up and whine about how you don't appreciate him when you least expect it.