Study for Pediatric Autoimmune Neuropsychiatric Disorders

Inclusion Criteria (All participants): * Child age 3-17 years old * Child and their parent/guardian are able to complete all study activities in English * Potential participant's family plans to be followed within UW Health or Dartmouth Health for at least one year Inclusion Criteria (In primary care group only): * Pediatric patient who is a current member of the primary care population at either UW Health or Dartmouth Health * Abrupt onset of symptoms (within 7 days) occurring in the past 3 months. Willing to come in-person for at least the baseline visit. * Suspected diagnosis of PANS or PANDAS based on published criteria: * PANS: (A) Abrupt, dramatic, overnight onset of obsessive compulsive disorder (OCD) or severely restricted food intake; (B) concurrent abrupt onset of additional severe neuropsychiatric symptoms from at least 2 of the following 7 categories: 1. Anxiety 2. Emotional lability and/or depression 3. Irritability, aggression and/or severe oppositional behaviors 4. Developmental regression 5. Deterioration in school performance 6. Sensory or motor abnormalities, including heightened sensitivity to sensory stimuli, hallucinations, dysgraphia, complex motor, and/or vocal tics 7. Somatic signs and symptoms, including sleep disturbances, enuresis or urinary frequency consistent with a known neurologic or medical disorder. AND (C) symptoms not better explained by another medical or neurologic disorder * PANDAS * Presence of OCD and/or tic disorder * Pre-pubertal onset of symptoms (i.e., 3-12 years old) * Episodic course characterized by very acute and severe onset and dramatic symptom exacerbations * Neurologic abnormalities present during symptom exacerbations-motoric hyperactivity and adventitious movements * Temporal relationships between group A streptococcus (GAS) infections and symptom exacerbations Inclusion Criteria - External to Primary Care Group ONLY: * Abrupt onset of symptoms (within 7 days) occurring in the past 4 months. * Confirmed diagnosis of PANS or PANDAS based on published criteria (see above). Exclusion Criteria (all participants): * History of tics, OCD or food restriction/avoidance that contradicts a history of sudden onset or was present before the onset of this investigation * Current symptom(s) of Pica * Previous participation in the study * Not suitable for study participation at the discretion of the site investigator (e.g., the child does not have verbal or cognitive ability adequate for self-report assessment) * Patient or family is unable to complete the study questionnaires or procedures in English as the primary language