Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS) and Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS): Immunological Features Underpinning Controversial Entities.

Pediatric acute-onset neuropsychiatric syndrome (PANS) and Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS), represent an overlapping group of disorders which is characterized by acute-onset obsessive compulsive disorders, eating restriction, tics, cognitive and behavioral deterioration which typically follows a relapsing-remitting course but some patients have a primary or secondary persistent progress. This condition is likely caused by heterogeneous inflammatory mechanisms (autoantibodies, complement activation, pro-inflammatory cytokine production) involving the basal ganglia as evidenced by imaging studies (patients vs. controls), sleep studies that found movements and/or atonia during REM sleep, and neurological soft signs that go along with basal ganglia dysfunction.