I just found out yesterday that I have seroconverted. My titer level is 2.33. It was 0.08 six months ago, when I was last tested. I found this out at my PCP's office yesterday... still waiting to hear from my neurologist. Thus, I've made an appointment with a new neurologist, but I couldn't get in until after my next infusion is due. Will I be ok to get one more? I know this is sort of an impossible thing to answer. (No prior immunosuppressives except IV steroids and somewhere between 6-7 yrs on Tysabri). Thank you!
If I understand you correctly, you’ve been on Tysabri for 6-7 years and became JCV antibody positive (high titer) in the past 6 months with no other risk factors for PML.
If you are asymptomatic (i.e. no new neurological problems to suggest PML), we would typically recommend delaying your next infusion for at least a month and obtain a new MRI of the brain. It is important that the MRI include diffusion weighted images (DWI), since this sequence is useful for the detection of early PML. Remember, PML is rare (approximately 1%) even in people with your circumstances.
Your risk of an MS relapse after stopping Tysabri is minimal for the first 3 months, so you have time to figure things out and either remain on tysabri using extended interval dosing (every 8 weeks) with more frequent MRI monitoring (every 4 months) or switch to another DMT.
Your PCP should be able to help with these recommendations until you establish care with another neurologist.
Revere (Rip) Kinkel MD
Professor of Clinical Neurosciences
Director of the Multiple Sclerosis Program
Clinical Neurosciences Director
University of California San Diego
200 West Arbor Dr
Medical Offices North MC 8687
San Diego, CA 92103