My son has PANDAS. His anti brain antibody numbers were 400% elevated, worse than 3 east coast doctors have ever seen and we were sent out to CA to see an immunologist there. It was horrific for us as my son also has autism and was doing amazing, then PANDAS hit and we lost him a 2nd time.
The problem with PANDAS is you can have symptoms LONG LONG LONG after strep is gone. With PANDAS, there is an autoimmune response to the strep, the body messes up and now for some reason thinks the basal ganglia part of the brain is a strep infection, so it fights it constantly. Your brain never leaves so the fight is always there even when strep is long gone. Antibiotics help and other meds help while the body slowly reacts less and less and strep titers come down. We tested my son's titers for 4 years and it took that long for them to go from sky high to normal range. We also had to do 16 IVIG treatments to get there.
My suggestion to anyone with PANDAS kid, if you use probiotics, make sure the strain S. Thermophilis is not it in, and do not feed your kid yogurt as this strain is one of the "other active cultures" in every single yogurt on the market.
The body reacts to strep, and even though S. Therm. is a beneficial strain, for most PANDAS kids, strep is strep it causes a reaction. My son was doing better with the PANDAS and we decided to give him a yogurt to test his milk/casein sensitivities not knowing about the S. Therm and OMG what a disaster. We caused an instant 6 month regression. It was horrible.
What we saw when we suspected PANDAS was an overnight dramatic change in our son. The onset is usually very rapid, overnight. OCD, handwriting gets worse, vocal tics, motor tics, really wild emotional mood swings. My son could go from happy go lucky, to homicidal, to crying like a baby curled up in a ball and back to playing happily in about a 7 minute time frame. It was scary.