I have a question in which I’m having a hard time getting an answer to. This is my go to place looking for information that is typically two sided or even non-opinionated. When I was diagnosed with MS, I was placed on Tysabri. From what I understand, everyone is either positive or negative for the JC virus even if you don’t have MS. The reason they want to know is that Tysabri can elevate your JC level to such an extent that it can actually cause death. It’s actually happened before. 11 years ago they began assigning a number to your JC level, I guess to give them a gauge of where to cut you off if your own Tysabri. I tested positive and get checked every six months for my levels. If you’re 3 or over, you were at extreme high risk for a PML. Fluctuates the highest being 1.24 and a .64 on the low end what has happened is baffling me. My last two blood draws came back that I was JC negative. I cannot make sense of this. If we’re all positive or negative I wonder why I just went negative for two blood draws in one year. I’m back positive again and usually keep a number. I can’t say anything negative about Tysabri I just can’t wrap my brain around the scenario I explained. Anyone on here that understands the JC virus have any opinion on this matter? No one seems to have any idea how I just poof! Became negative for two cycles, and then it returned..
JC or John Cunningham Virus : I have a... - My MSAA Community
JC or John Cunningham Virus
I might suspect there was an error in the labwork done🤔
I tested JC positive and neuro said she no longer prescribed tysabri to newbies if positive as there were other meds, this was in 2O15.
.Hi Mark1499 🙂!I was on tysabri for7 yrs & came up positive for the JC virus after 5 yrs on tysabri. I'll tell ya I was scared of PML & switched my DMT to po meds myself.
I wish I can help ya. Hope you find some answers. Best of luck.
🙏🧡Lisa 💕
My sister took Tysabri and freaked out when she got to a 2 so she switched DMTs. I’m not really worried about a PML I’ve been on it for 5 years and haven’t gotten over 1.59. It’s the positive when I’m diagnosed, fluctuates between 1.59 and.64 then it just disappears twice then comes back. 🤷
I don't know that answer either I've never heard of that. I'm positive so I take a DMT that the PML won't happen .
40% chance of a false negative result.
The tests that are done are not for the JCV virus itself, but for the antibodies against JVC virus. If the antibody level rises it indicates that the JVC virus, which has been dormant, may now be active. If it is activated, it may cross the blood-brain barrier and cause PML.
Antibody levels can vary; sometimes they are undetectable resulting in a negative test. It doesn't mean that the test is in error or that you no longer harbor JVC.
Thank you, that’s the best explanation I’ve heard. You told me what no one has been willing or knew Enough to tell me about. It’s not that I’ve been stressing. I’m just been baffled. I hope you have a great day.
Blood testing is not always 100% accurate and if a sample has not been handled as it should have been then that may affect results - and blood tests can also return a false positive even when handled correctly. I'm not sure if it's still the case, but it used to be that all JCV tests were done in a European laboratory (Denmark? Sweden?) so that increases risks of samples being mishandled in transit if it is still the case.
And because the human body is not a machine, levels can fluctuate anyway. Here's one study where a few of the people involved went from positive to negative (as well as some who went the other direction).
onlinelibrary.wiley.com/doi...
People who are interested in the subject of PML risk might find the following interesting.
clinicspeak.com/understandi...
It has also been found that extending the dosing interval from 4 weeks to 6 weeks can very significantly reduce PML risks - you can see that in the risk calculator on the link above. Quite a few neuros are doing extended interval dosing with patients on Tysabri and if their MS remains well controlled at the extended interval then they continue on that regime. I've heard of some where the "sweet spot" is a 5 week dosing schedule.
Can't figure that one out either I wanted to start with tysabri when first diagnosed, as I knew a couple people who were doing quite well on it , but my neurologist didn't like the idea because of my JC virus status
Tysabri has served me well and my JC levels are usually pretty good. I’m just baffled about the negative after having tested positive from the start.
Hi Mark I was on & off Tysabri for over 11 years, each time my JVC went up I was put on something else that worked for a while then I had a relapse back on Tysabri. When my JVC went up again I was put on something else for a while again. I had a real bad exercbation back in Fall of 2014 I wound up in a Nursing home for over 3 months. I had to learn how to walk & talk again my Neuro sent me to Cincinnati Ohio to an MS Specialist. We talked Tysabri & a few other things. He said my chances of getting PML was less than 10%, compared it to me walking out my door & getting run over by a Taxi Cab. I felt a big whoosh & said I would rather live with that chance than live the way I was. When I spoke I sounded like a person who had a stroke, my hands wouldn't work together & I couldn't walk very far with out having to stop & rest a bit. I got out of Nursing home Dec 7th 2014. I am now turning 71 in 1 month. I get around pretty good for an old lady who has been dealing with the MonSter of MS for over 30 years. I am NOT complaining I owe it all to My God in heaven. YEAH!!
God bless you seemed to have grown quite gracefully in Jesus Christ. Reading your reply the spirit brought a calm that I can’t put into words. You have helped my faith! My plans are to stay on Tysabri because it may never be an issue. Please add me to your prayer list. I’m skydiving on the 14th for the 1st time at 62 with MS! I’m not really afraid I know where I’m going should anything go south! That’s not the request. My 25 year old son recently married and his wife hates me! He’s gotten to where he want call his mom unless he’s alone. They were on speaker phone the other night and before they hung up I said, I love you son! He didn’t even acknowledge it. I have a massive hole in my heart! This is what my prayer request is for!
I am so glad you got comfort from my answer, I believe God is with me everyday for in the bible it says "I will never forsake you". This I believe with all my heart. You are already on my prayer list, I have asked special prayers for your skydiving adventure! Besafe & have fun. Mary
Iam praying!
New to the group..worried about taking Tysabri. 
Undecided 
PML odds have gone crazy
Tysabri questions
Aetna and ocrevus 
