My son is 20 years old now and has struggled with PANS for most of his life due to immune deficiency and chronic sinusitis. Recently we began seeing a local immunologist who does lots of work with metabolic disorders, believing that mitochondrial dysfunction is the root of much immune dysfunction since we need mitochondria to form inmmune cells properly. He did extensive blood work, followed by a muscle biopsy, and then genetic testing. All tests found abnormalities that eventually led to discovering a genetic mutation in a gene that helps mitochondria to function properly. This really helped us to make sense of everything and he is now on mitochondrial supplements. He has only ben on for a month, but his immune numbers looked better than they ever have on his most recent bloodwork.