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    Jc virus
    May715 posted:
    My sister has taken Tysabri for 2yrs. now for her MS. She was just diagnosed with JC Virus. The Dr. Was not very clear with her about it and told her it was up to her if she wanted off the treatment. My concern is, now that she had been diagnosed with Jc virus, what will happen next? Can anyone else relate to this?
    hackwriter responded:
    Dear May,

    Being JCV positive means that her risk of developing PML, a fatal brain infection, is higher than for a patient who is JCV negative.

    Some Tysabri users who are JCV positive do stay on the drug because it is keeping their MS in check and they are willing to take the risk.

    Those at highest risk for PML are those who have these three risk factors:

    1. They are JCV positive,

    2. Have weakened immune systems from taking certain immunosuppressant drugs prior to starting Tysabri, and

    3. Have taken Tysabri for more than two years.

    Your sister should take these risk factors into account when making her decision to continue with the drug.

    Being JCV positive doesn't mean she'll get sick, the JC virus itself is not symptomatic. Exposure to it makes her susceptible to more serious infections, and so she should be careful taking medications that weaken the immune system.

    Hope this helps.


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