I was recently diagnosed with MS on top of having Lupus and I just had a long discussion with my MS specialist about the JC Virus bc the thought of it scared me too. JC Virus is a virus that can cause a VERY RARE brain infection. They were able to tell if I tested positive for the antibodies through a blood test. Do you know what your level is? Bc that makes a huge difference. Just because you text positive for the antibodies DOES NOT MEAN that you will get the brain infection. Your doctor should have explained all of this to you instead of letting you worry!

Praying for you.

In an article, "Progressive Multifocal Leukoencephalopathy and Systemic Lupus Erythematosus: Focus on Etiology" found in the NCBI database, I read that a Low Lymphocyte count has been implicated in the activation of the virus, which can be caused by Lupus or the drugs used to treat Lupus. I also read that if the virus causes Progressive Multifocal Leukoencephalopathy, that the diagnostic tool would be the lumbar puncture with MRI. If the virus were to cause encephalopathy, the goal of treatment would be to "eliminate the virus and increase lymphocyte counts without aggravating any SLE manifestations". From the article, there are examples of a good outcome: "[a] clinical case study with a combination of the antiviral agent CMX001, an oral formulation of cidofovir and recombinant human interleukin-7 (CYT107), an inducer of CD4+ and CD8+ T cells, reported successful treatment in PML".

The take aways are: even if it progressed to PML, there are treatments and one of the ways to prevent it from becoming PML is to make sure the low lymphocyte count does not occur.

Citation info:
Berntsson SG, Katsarogiannis E, Lourenço F, Moraes-Fontes MF. Progressive Multifocal Leukoencephalopathy and Systemic Lupus Erythematosus: Focus on Etiology. Case Rep Neurol. (Phone number can only be seen by the question and answer creators). Published 2016 Mar 16. doi:10.1159/000444874

I have heard of it, but I don't know very much about it. Definitely don't take Rituximab.

JC virus is thought to be gotten in childhood, at which time it is asymptomatic. It can then reactivate later in life when the immune system is suppressed in some way. What symptoms precipitated your doctors checking for JCV? Were they evaluating for PML?🙏💚