Antibody for POTS?

[calypso]

My neurologist tells me although it's not a definitive test, that there is an antibody that often is present in POTS patients. He's thinking about doing the test to decide if I for sure have POTS.

Anybody know about this antibody or what it means?

[MightyMouse]

It's actually not all that common...but there is subgroup who has it. Currently, knowing you've got it wont change your treatment, but maybe someday?

here's the abstract:

Autoantibodies to ganglionic acetylcholine receptors in autoimmune autonomic neuropathies.

Vernino S, Low PA, Fealey RD, Stewart JD, Farrugia G, Lennon VA.

Department of Neurology, Mayo Clinic, Rochester, Minn 55905, USA. verns@mayo.edu

BACKGROUND: Idiopathic autonomic neuropathy is a severe, subacute disorder with a presumed autoimmune basis. It is indistinguishable from the subacute autonomic neuropathy that may accompany lung cancer or other tumors. Autoantibodies specific for nicotinic acetylcholine receptors in the autonomic ganglia are potentially pathogenic and may serve as serologic markers of various forms of autoimmune autonomic neuropathy. METHODS: We tested serum from 157 patients with a variety of types of dysautonomia. Immunoprecipitation assays with iodine-125-labeled epibatidine and solubilized human neuroblastoma acetylcholine receptors were used to detect autoantibodies that bound to or blocked ganglionic receptors. RESULTS: Ganglionic-receptor-binding antibodies were found in 19 of 46 patients with idiopathic or paraneoplastic autonomic neuropathy (41 percent), in 6 of 67 patients with postural tachycardia syndrome, idiopathic gastrointestinal dysmotility, or diabetic autonomic neuropathy (9 percent), and in none of 44 patients with other autonomic disorders. High levels of the binding antibodies correlated with more severe autonomic dysfunction (including the presence of tonic pupils). Levels of these antibodies decreased in patients who had clinical improvement. All seven patients with ganglionic-receptor-blocking antibodies had ganglionic-receptor-binding antibodies and had idiopathic or paraneoplastic autonomic neuropathy. CONCLUSIONS: Seropositivity for antibodies that bind to or block ganglionic acetylcholine receptors identifies patients with various forms of autoimmune autonomic neuropathy and distinguishes these disorders from other types of dysautonomia. The positive correlation between high levels of ganglionic-receptor antibodies and the severity of autonomic dysfunction suggests that the antibodies have a pathogenic role in these types of neuropathy.

Nina

[Deb]

Nina's right about the antibody being rare, as opposed to often. I had the test done, along with several others, because the neurologists thought I might have a tumor that was secreting antibodies that were attacking my nervous system. They also wanted to check for other antibodies (I think they are also called markers) that were created by viruses that could also be attacking the nervous system. I believe the test is called a titer test. Anyway, I had several tubes of blood taken from my arm under special conditios, and it was sent to the Mayo Clinic. All of the tests came back negative, yeah for me!!!!!!!! So I was happy, but somewhat let down, too, because they couldn't find the cause of my POTS. But like the docs said, it is worse to have a problem with the autoimmune system, and far worse to have cancer.

If your doctor thinks you might have a problem, then get the test so that you'll know one way or another. But don't get your hopes up that it will change anything for the better. It will give you peace of mind if it comes back negative.