What does a positive JCV antibody mean?
A blood test is the only way to identify the presence of the virus. When someone says that they’re “JCV-positive,” or “JCV+,” they mean that they’ve had a blood test that was positive for anti-JCV antibodies. Most people with MS are likely to have been tested for the JC virus early in their treatment.
What is considered a high JCV index?
Previously, different anti-JCV antibody index categories have been defined for PML risk stratification and the cut points 0.9 and 1.5 included in the label of natalizumab [8, 21]–in the following termed as low (≤0.9), medium (>0.9 and ≤1.5) and high (>1.5) JCV index category.
What is stratify JCV TM AB with index W RFL inhibition?
26029 Stratify JCV ™ Ab (w/Index) w/Rflx to Inhibition Assay (91665) The JC Virus (JCV) is associated with progressive multifocal leukoencephalopathy (PML). Detection of antibodies to JCV in serum OR plasma is a reliable indicator of exposure to JCV.
How long does it take to get JC virus results?
Samples are shipped every 4 – 6 weeks and the result should be available from the referral laboratory within 2 weeks of receipt of the sample.
Can Ocrevus cause PML?
One year of Ocrevus (ocrelizumab) treatment does not increase the risk for a rare brain infection — called progressive multifocal leukoencephalopathy (PML) — in people with multiple sclerosis (MS), a study suggests.
What is the number range for the JC virus?
An index >0.40 denotes anti-JCV antibody positivity, index <0.20 denotes anti-JCV antibody negativity, and index ≥0.20 but ≤0.40 denotes indeterminate response requiring further evaluation in the confirmation test.
What are the chances of getting PML while on Tysabri?
The risk of developing PML increases with the number of Tysabri infusions received. Tysabri is administered as a single intravenous infusion every four weeks. The overall worldwide cumulative rate of PML in patients who have received one or more Tysabri infusions is 0.5 cases of PML per 1,000 patients.
Can you get PML If you are JCV negative?
If the test finds no JC virus in your blood sample, (often referred to as JCV negative) the risk of PML is very small (less than 1 in 10,000). 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.
How do you catch JCV?
The high prevalence of JCV in urine and in sewage and the stability of the viral particles observed suggests that contaminated water, food, and fomites could be the vehicles of JCV transmission through the oral route.
Is there a blood test for PML?
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. Before you start treatment with Tysabri you will be given this blood test at the start of your treatment, as well as an MRI.
How do you test for JC virus?
Tests can detect if you carry the JC virus. Your doctor might look at a sample of your tissue under a microscope or check your blood for signs that your body is fighting the infection. This is important to know if you know you have a weakened immune system or if you take drugs that suppress your immune system.
What does a positive JCV test mean?
This JC virus-detecting test can determine if a person has been exposed to the virus and if it’s present in their body. A positive test doesn’t mean a person with MS will develop PML, but only JCV-positive individuals can develop PML. Knowing that you’re JCV-positive alerts your doctor to watch for PML.
What causes JC virus?
The JC virus can be activated when a person’s immune system is compromised because of disease or immunosuppressive medication. The virus can then be carried into the brain. It infects the white matter of the brain and attacks the cells responsible for making myelin, the protective coating that covers and protects nerve cells.
Is JC virus contagious?
Response from Dr. Feinberg. It isn’t clear how people get infected with JC virus (which causes PML) or whether people with PML are contagious to others. It can’t be terribly contagious, because no one has reported spread of the disease in hospitals or nursing homes that I am aware of.