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    JC Virus
    AuntDut posted:
    My sister was diagnosed with MS in 1995. She has been on every form of therapy but has had adverse reactions, last hope was Tysabri. After being on it 1 year she had a blood test and found out last week she has the JC virus. Evidently this can lead to the PML virus. We are desperately seeking information on these viruses. She has been told they could "wash" her blood to try to prevent the PML virus. We would like to know the chances of her getting the JC virus without the washing and if she should discontinue her treatments. Her MS physician's office does not seem to be a lot of help in giving her information. I am 3 states away and cannot go to appointments with her and her husband, they don't ask many questions. Anyone have any information on these viruses?
    Rory26312 responded:
    Hi Auntdut

    As a possible Tysabri user I recently submitted a blood sample for the JC virus(JCV) in the Stratify-2 study and am still awaiting results at my next neuro appt.

    As it was explained to me the having (JVC) means that you are more at risk of devoloping PML than if you do not have it.(JVC)

    That been said the study documents state that "the test results from this study should not be used in making treatment decisions"

    I am not sure what the are to be used for other than the specific aims of the study which seems to finding out if there is a link between PML and JVC .

    I have no idea about this washing of her blood but if it is not an approved procedure covered by insurance be very wary.

    Last thing if her current doctor is not doing his/her job it may be time for a change and I would consider leaving her in limbo as to her treatment options to be falling down on the job.

    For one thing there is Gilenya the recently approved tablet to think about.

    Hope this helps and let us know how she is doing.

    Neil S Lava, MD responded:
    JC virus is not that uncommon and many of us have been exposed and would have positive blood tests for this virus. Although having a positive blood test may be a risk factor for PML, it does not mean that she will get this disease. The risk for PML at 2 years is 1 in 1000.
    If her MS physician is not able to help, then perhaps a different MS physician might be more helpful.

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