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Possible Link Between MS Agent and Shingles

April 7, 2016

There is a report of a woman with relapsing-remitting MS, who developed shingles while being treated with MS agent Tecfidera. This has raised questions of whether the drug re-activates the varicella-zoster virus, otherwise known as “the chicken pox”.

Once someone is infected with this virus, it remains dormant in the body. Obviously as a child the chicken pox are not a huge deal, but when the disease is active in an adult, it is known to cause shingles, which are a bit more serious.

The study was recently published in the journal Neuroimmunology and Neuroinflammation. Shingles more frequently occurs in immuno-compromised individuals than in healthy people, and treatment with various MS disease-modifying drugs have been linked to the virus’ reactivation.

Clinical trials of dimethyl fumarate in MS flagged the drug as safe in this respect — finding no increased risk for shingles among treated patients compared to placebo. The risk for shingles does, however, increase with age as the numbers of immune cells decrease.

The 40-year-old woman was admitted to the hospital with pain and a weakness in one of her legs, as well as a rash on her abdomen. She had been treated for RRMS with dimethyl fumarate for the past six months.

Since the medical team did not find any evidence of MS progression, it suspected shingles and stopped the dimethyl fumarate therapy, providing her with oral antiviral treatment. Her condition, however, worsened, and it soon became obvious that the shingles episode was what is known as disseminated shingles.

The virus usually reactivates only in some spinal nerves, affecting a particular area of the body. But in people with reduced immune responses, the virus more often becomes active in several segments of the spinal cord, leading to the widespread symptoms of disseminated shingles.

This treatment has recently been linked to progressive multifocal leukoencephalopathy (PML), which is associated with John Cunningham (JC) virus infection.