Tysabri is my current MS therapy. As an African American MS tends to be more aggressive for us so we must be equally aggressive with our treatment. Tysabri is the most aggressive treatment that I am aware of. Since it is so aggressive, there is a down side of course. With it comes the risk of developing a fatal brain disorder called PML caused by JC Virus or JCV.
JC Virus was first isolated from the brain of a person suffering from Hodgkin's disease & PML . PML tissue contains virus-like particles in the nuclei of abnormal oligodendrocytes, which is the pathognomonic cell of the disease. JCV will only grow in a very restricted range of cells, mainly in the brain. JCV is known as a DNA virus that maintains a latent infection in the body which can be reactivated from time to time. The oligodendrocytes in the peripheral zone surrounding an area of demyelination are grossly abnormal. The nuclei of abnormal oligodendrocytes are packed with JCV. Typically, PML evolves gradually, with impairment of mental function and disturbance of speech and vision. Movement may also be affected. The disease then progresses rapidly and patient is severely disabled, eventually becoming demented, blind, paralyzed and finally, coma and death.
Antibodies of JC virus in the Cerebral Spinal Fluid (CSF) is rare but if detected, it suggests active multiplication of JCV in the Central Nervous System (CNS). Cytarbine is an anti-viral drug that has proven to be somewhat effective against PML. Out of 8 cases, long term improvement was only seen in 2 cases. Another case had a dramatic response within 24 hours but was not maintained. Rapid progression was halted in 1 case but the neurological damage was severe. The other 4 cases did not show any improvement.
Our immune system routinely keeps the virus in check. Anyone with a weak immune system run the risk of developing PML. Life is risky every day. I am too blessed to be stressed.