PML (Progressive Multifocal Leukoencephalopathy)

Progressive Multifocal Leukoencephalopathy, more commonly known as PML, is a severe brain infection that usually results in death. It is a disease of the white matter of the brain that can develop simultaneously in several areas. PML is often referred to as an opportunistic infection, meaning the infection attacks only when the body’s immune system is too weak to defend against disease. PML is caused by the JC virus, which attacks the body when the immune system is weakened. The JC virus is often attained during childhood and remains in the person’s body as they enter adulthood. Even as adults, most people with the JC virus still do not develop PML. However, if a person’s immune system is weakened or suppressed, the JC virus activates. This results in PML attacking the brain and central nervous system.

There are many symptoms of PML (Progressive Multifocal Leukoencephalopathy). Early symptoms include: weakness in extremities (hands or legs), trouble concentrating or developing thoughts, impaired coordination. As PML progresses, there are more serious symptoms, including:

Diagnosing PML can be done in a few different ways. First, physicians sometimes diagnose PML through MRIs (Magnetic Resonance Imaging). Second, performing a spinal tap (insertion of a needle into the spine to collect spinal fluid for examination) is another method by which PML can be diagnosed. The third and final way to diagnose PML is the most invasive, a brain biopsy. Although there are multiple ways to diagnose patients with PML, diagnosis is still a challenging task because of how rapidly the infection progresses. Once the brain infection starts to develop, lesions form on the brain. This results in every patient experiencing different symptoms because the lesions can form on different parts of the brain. Therefore, there is no usual or common progression of the disease.

The prognosis for this brain infection is often very serious. According to the National Institute of Health, patients usually suffer from PML for several months. Sadly, over 80% of PML patients die within the first six months. For the remainder of their lives, patients suffering from PML continue to experience irreversible neurological problems, including loss of coordination/movement, memory loss, and vision problems.

Most often, people suffering from AIDS develop PML because their immune system is weakened. However, drugs that suppress the immune system have also been linked to PML. Most notably, an anti-psoriasis drug called Raptiva has been linked to PML. After the death of some patients and countless others suffered from PML, Genentech, manufacturer of Raptiva, removed the drug from the United States market. The removal of Raptiva (Efalizumab) from the market came mainly as a reaction to its link to a number of reported cases of progressive multifocal leukoencephalopathy (PML) in Raptiva users. A statement released by Genentech said they anticipated Raptiva being unavailable in the United States by June 8, 2009. As a result of the recall, physicians and healthcare professionals were asked to stop prescribing Raptiva and begin alternative treatment methods for patients already using Raptiva.

Raptiva is not the only drug linked to PML. Other drugs linked to PML risk are Rituxan, Tysabri, Campath, and Cellcept. In September 2008, a patient with rheumatoid arthritis was prescribed Rituxan. He later died from PML. Following his death, the manufacturer of Rituxan (Genentech) added a warning to Rituxan labels that PML was a possible side effect. The FDA has also indicated that PML is linked to Tysabri, a drug used to treat multiple sclerosis. This FDA warning followed reports of two patients developing PML. In 2005, Tysabri was removed from the market after three more patients developed PML. However, the drug regained approval in 2006.

Treating this brain infection is very difficult because most antibiotics and medications cannot successfully enter the brain. Unfortunately, there is currently no proven treatment for PML.

Please CLICK HERE for a free consultation.