Thank you so much for the response. He has been through a host of testing and came back showing mycoplasma, coxsackie, HHV-6, and western blot positive for 3 bands. Immunologist says he does not have Lyme because he does not have 5 bands per CDC guidelines, which I am skeptical about his opinion on that.
Currently strep antibodies are negative, but have been positive in the past. He's been suffering through this for a good 14 years. He was diagnosed with high functioning autism at age 3, so for years we just assumed it was that. But we started noticing a pattern with illness, and each time resulting in some serious regression. He is now 16 years old and cannot go to school anymore nor leave the home. His last big exacerbation was it 14 years old, during which time he had a psychotic episode. His cognition has declined by 15 points on his IQ test. He has become severely disabled by this and can barely communicate anything. It's devastating because he was on an honor roll student in between his flare-ups and had several friends. Now he is homebound and a social.
I will contact his immunologist and his pediatrician regarding his reaction to the steroid and hopefully they will have some thoughts.