Pml virus symptoms

Home » Medications » PML «. Printer-Friendly Version. Progressive Multifocal Leukoencephalopathy Progressive multifocal leukoencephalopathy PML is a rare and usually fatal viral disease that is characterized by progressive damage or inflammation of the white matter of the brain at multiple locations. It's an opportunistic viral infection of the central nervous system CNS that typically occurs in people with an immune deficiency due to immunosuppressive medications.

It's normally kept under control by the immune system, causing no problems. If the immune system is weakened and the body is less able to fight an infection, the virus can reactivate and cause serious and potentially fatal inflammation and damage to the brain known as PML.

PML is a demyelinating disease, just as in multiple sclerosis MS. It affects the white matter, which is mostly composed of axons from the outermost parts of the brain or cortex.

The risk of developing the infection has been identified as a potential side effect of treatment with some of the disease modifying drugs for MS, in particular Tysabri natalizumab. When you are infected with the JC virus you develop antibodies to the virus.

A blood test can detect the presence and level of these antibodies and help give an estimate of your risk of developing PML. Altogether, PML occurs in approximately one in , people.

The term "progressive" in PML means that the disease continues to get worse and often leads to serious brain damage. These symptoms include: general weakness that steadily gets worse. It's caused by a virus called the JC virus. Most adults carry it, and it usually doesn't cause any health problems. But it can if you have a weak immune system -- if your body's natural defenses against illness aren't working right.

Immunosuppressive medications that have been associated with PML include cyclophosphamide, corticosteroids, mycophenolate mofetil and monoclonal antibodies including natalizumab Tysabri , rituximab Mabthera and alemtuzumab MabCampath 8. The best way to treat PML is to fight whatever has made your immune system weak. You also might need to avoid treatments like chemotherapy, which can put you at higher risk of infections. If the blood test finds JC virus JCV positive , this indicates that you are at a higher risk of developing PML , although for most people the risk is still small.

If the immune system becomes severely compromised for any reason, the virus can be reactivated. Then it makes its way to the brain, where it multiplies and begins its attack on myelin. As myelin is damaged, scar tissue begins to form.

In natalizumab-treated patients without previous immunosuppressive treatment, the JCV antibody index is used to stratify PML risk. When you are infected with JC virus you develop antibodies to the virus.

A test called Stratify JCV can detect the presence and level of these antibodies in your blood, which can be used to estimate your risk of developing PML. Motor and sensory disturbance, characterised by lack of coordination, gait disturbance, ataxia, hemiparesis or visual deficits may also be found at the time of presentation 2. Seizures, language difficulties and headaches can occur but are less common. These signs and symptoms progress over the course of a few weeks and death can occur weeks to months after diagnosis.

Many of these reports had multiple risk factors including prior or concomitant immunosuppression therapies, underlying disease and chemotherapy. The majority of reports were associated with the monoclonal antibodies, rituximab and natalizumab.

However, this may be due to greater awareness of PML in association with these particular medicines. Improved chance of survival is associated with early diagnosis, younger age at diagnosis and if the disease is limited to one lobe of the brain 1. Current treatment of PML is limited and is generally supportive in nature. The current treatment strategy for PML in HIV-negative patients is to restore the host adaptive immune response by stopping or decreasing immunosuppression 3.

There are currently no specific antiviral drugs for the JC virus. Recovery of the immune system can trigger immune reconstitution inflammatory syndrome IRIS.