Is PANDAS, pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections, a legitimate medical condition, and if so, what is the cause and best treatment?

This has been accurately diagnosed in some people but it is often misdiagnosed and this is true of other conditions, as you are aware, such as chronic Lyme disease. While it can occur, it is not always the explanation for the constellation of symptoms observed within a child. As you suspected and as demonstrated by your work with these two boys in the [name withheld] family, there can be a spirit possession situation ongoing concomitant with the infection episodes. And this can confound the interpretation and cause a misinterpretation to happen and this is what is happening here.