Jumping in with a different perspective.
Was your son vaccinated?
Vaccine adjuvants are designed to cross the BBB, specifically aluminium. There was much discussion on this site that Pandas is a version of aluminum toxicity. With vaccines, the aluminum is designed to hold onto the antigen and keep it in the body long term; thereby introducing antigens into the brain as well. It is believed that detoxing from aluminum and mercury helps quiet the immune system.
We have tried selenium for mercury, malic acid for aluminum and other stuff as well. She is probably not all clean, but definitely is aluminum sensitive- she cannot tolerate aluminum based deodorant. She is currently using Diatomaceous earth for a slow detox for everything. I think it is helping well.
I have learnt about vaccine reactions about seven years ago, and have not vaccinated my kids since. I have 2 totally unvaccinated kids, and several partially vaccinated. It is a CRIME what pharma is doing to our kids without knowing the long term effects. I can honestly say, VACCINES ARE NOT WORTH IT! Which parent would not nurse a child through a bad case of pertussins or measles, and even sweat the time through the a hospitalization for physical problems versus dealing with what we are dealing with here?!!! Just venting my pain. I wish I would have known about this issue many many years ago.