I just saw my neurologist today (every 6 months since I'm on Tysabri). He is at a big medical school and does research as well. He has been reading research on copper and zinc deficiencies which are associated with demyelinating disorders.

He and the NIH are doing research on the JCV antibody test. They used to think the false negative rate was 2.5 %. Now it could be more like 10-12%. In other words, some people who were negative are becoming positive (he didn't say how many cases). They are trying to figure out why this is happening. He's now adding a PCR test for the virus with every infusion (I get them every 8 weeks) which looks for JC virus DNA in your blood. It's a way, on an offhand chance, to pick up the virus in your body if you have a false negative situation going on.

They also think the problem might be there is more than one strain of JC virus so the assay test might not be picking up the strain you have, or maybe your body doesn't produce the antibodies in a great enough number to register on the assay (test). They think that maybe only one particular strain causes PML. He said it will take a year for them to sort all of this out.

He said this spring they refined the JCV antibody test so I will get the new one at my next infusion. I think it has been refined to catch some of the false negatives. I can't remember how exactly the test has been made better.

Thought I would share!