Merkel Cell Polyomavirus Associated With Rare Skin Cancer, Merkel Cell Carcinoma Sep 26, 2009
MCPyV DNA was detectable in 24 (77%) of the 31 Merkel cell carcinoma tumors available, with 22 (92%) of these 24 patients also carrying antibodies against MCPyV. Among the 451 control subjects, prevalence of antibodies against the five human polyomaviruses was 92% for BK virus, 45% for JC virus, 98% for WU polyomavirus, 90% for KI polyomavirus, and 59% for MCPyV.. Although infection with MCPyV is common in the general population, MCPyV, but not the other four human polyomaviruses, appears to be... (Science Daily)
Strategies To Counteract Side Effects Of New MS Therapies Sep 15, 2009
This severe brain infection is triggered by the JC virus found in about 80% of all adults ... The treatment was targeted at re-establishing the patients own immune system to enable it to eliminate the JC virus. (Science Daily)
Virus Responsible For Deadly Brain Disease Found In MS Patients Treated With Natalizumab Sep 11, 2009
"This virus the JC virus, named for the initials of a patient is found in about 90 percent of the population," explains Igor Koralnik, MD, the study's senior author and director of the Human Immunodeficiency Virus/Neurology Center at BIDMC. "But in healthy individuals the virus lies dormant in the kidneys and causes no problems." Urine samples of healthy individuals may, therefore, show evidence of the benign virus. But, according to Koralnik, who is also Associate Professor of Neurology at... (Science Daily)
Scientists Find Clue to Dangerous Side Effect of MS Drug Sep 11, 2009
The drug seems to rouse the typically dormant JC virus from its slumber, allowing it to cross into the brain ... The JC virus is present yet dormant in about 90 percent of people ... After 12 months, measurements of JC virus in the urine rose from 19 percent (about normal) of samples to 63 percent at 12 months. (MEDLINEplus)
Asymptomatic Reactivation of JC Virus in Patients Treated with Natalizumab Sep 10, 2009
Most adults who are infected with the JC virus, the etiologic agent in PML, do not have symptoms. We sought to determine whether exposure to natalizumab causes subclinical reactivation and neurotropic transformation of JC virus ... Methods We followed 19 consecutive patients with multiple sclerosis who were treated with natalizumab over an 18-month period, performing quantitative polymerase-chain-reaction assays in blood and urine for JC virus reactivation; BK virus, a JC virus related... (New England Journal of Medicine)
Progressive Multifocal Leukoencephalopathy after Natalizumab Monotherapy Sep 10, 2009
We describe progressive multifocal leukoencephalopathy (PML) caused by infection with human polyomavirus JC virus in a patient with multiple sclerosis who was treated with natalizumab ... Magnetic resonance imaging (MRI) showed a presumed multiple sclerosis lesion, and JC virus DNA was not detected on polymerase-chain-reaction (PCR) assay of cerebrospinal fluid ... JC virus DNA was no longer detectable on quantitative PCR assay, and the patient's symptoms improved. (New England Journal of Medicine)
Reemergence of PML in Natalizumab-Treated Patients — New Cases, Same Concerns Sep 10, 2009
When progressive multifocal leukoencephalopathy (PML), a rare demyelinating disease induced by JC virus, appeared in 2004 as a complication of natalizumab treatment for multiple sclerosis, a more common demyelinating disease, it seemed an odd twist of nature. PML had never been reported in patients with multiple sclerosis, and to find patients who simultaneously had two demyelinating diseases with very different origins and pathologic characteristics was a dramatic surprise. (New England Journal of Medicine)
Biogen Tests Malaria Drug to Sever Tysabri's Deadline Brain-Infection Link Mar 24, 2009
PML occurs when a common germ, called JC virus, mutates, then evades the bodys immune defenses and penetrates the brain, causing irreversible damage. Researchers theorize that Tysabri may subdue defenses meant to keep the virus out of the brain. (Bloomberg -- US)
HIV & AIDS Feb 7, 2009
PML is an extremely serious brain infection caused by the human polyomavirus JC virus. Signs and symptoms vary and may include speech problems, weakness on one side of the body, loss of vision in one eye, or numbness in one arm or leg. (CNN -- Health)
