PML & Transplant Patients

Progressive multifocal leukoencephalopathy (PML) is deadlier in transplant recipients than in patients on natalizumab (Tysabri®) and rituximab (Rituxan™) therapy, according to a Mayo Clinic study presented at the 2010 annual meeting of the American Academy of Neurology.

In the study, a researcher reported that nearly 1 percent of transplant recipients contracted PML. That was "roughly 5 to 10 times the rate seen in patients" treated with Tysabri® or Rituxan™, according to Dr. Farrah J. Mateen. Dr. Mateen's study was reported in the online Medpage Today.

Tysabri® is an immunosuppressive drug to treat multiple sclerosis and Crohn's disease. Rituxan™ is used to treat rheumatoid arthritis, systemic lupus erythematosus, and non-Hodgkin's lymphoma.

About PML

PML is a lethal viral infection of the brain that occurs in patients with compromised immune systems. A virus, called the JCV (John Cunningham virus), lives harmlessly in 80 to 90 percent of adults. It is innocuous in healthy people, whose immune systems keep the infection in check.

But when the immune system is weakened, the once-latent virus travels to the brain where it attacks the myelin that covers the nerve sheaths. Myelin is a protective coating surrounding the nerves that enables the transmission of signals from these nerves to the rest of the body.

The latent PML virus is sometimes activated in patients who take immunosuppressive drugs after an organ transplant, who have HIV or AIDS, who are undergoing chemotherapy, and those taking immunosuppressive drugs to treat rheumatoid arthritis, severe plaque psoriasis, Crohn's disease and multiple sclerosis.

What Happens to PML Patients?

When the JCV attacks the brain, destroying the myelin covering the nerves, those parts of the body governed by the destroyed nerves begin to suffer. Clumsiness is usually the first symptom that PML patients experience. As the disease progresses, different parts of the brain's nerve tissue are destroyed.

Other PML symptoms include:

• Aphasia (being unable to speak, hear, read, or write properly
• Weakness
• Impairment of cognitive function
• Slow and distorted speech
• Problems moving the arms and legs, often on just one side of the body
• Headaches
• Difficulty with feeling in different parts of the body
• Visual problems, often resulting in decreased vision in half of the visual field
• Seizures
• Personality changes

Generally, patients live from about one to nine months after they are diagnosed with the disease. The average is six months.

Did you or someone you know develop PML symptoms and have a history of taking transplant medications? If so then contact our PML attorneys to for a free case evaluation.