Chris, I haven't got any information on steroids administered to people who are on Tysabri who develop PML.

I know there are people here who are or have been on Tysabri and have been determined to be in relapse who received a course of steroids.

As I understand it, as long as MRI shows lesions and inflammation consistent with relapse, a course of steroids may be administered. If ANY lesions are inconsistent with MS lesions (MS lesions are perpendicular, PML lesions may be blotchy, in unusual areas of the brain away from previous lesions, or may be at odd angles from normal MS lesions) steroids should NOT be administered.

I do know that IF a person has PML, is treated with plasmapheresis, and shows IRIS, steroids are part of the treatment for IRIS.

This was one of the problems my neuro talked about, that there are a lot of neuros and radiologists who hadn't ever seen PML because it was almost always seen in AIDS patients who were treated with strong immunosuppressants, but all AIDS patients who are on drugs don't develop PML. ( I went right to the head of my radiology department because he reads my MRIs and asked him straight out and got a very informative lesson in PML and MRIs.)

What we need is a test to check for JC virus, an easy one. Right now it appears that it's a combo of tests checking urine, blood and CSF. 80-85% of the population carries JCV in their kidneys. It's when it's activated into the blood and CSF that it becomes a problem, and in many people it never makes it to the brain.