Social and communication deficits *(all listed symptoms)

• Deficient social-emotional reciprocity
• Deficit in nonverbal communication (eye contact, body language, facial expression, gestures)
• Deficit in managing relationships
• *not general development delays

Repetitive behaviours (at least 3 out of 4 listed symptoms)

• Stereotypical speech and movement
• Ritualistic behaviour; resistance to change
• Fixated interests, perseveration of abnormal intensity
• Sensory dysregulation

Paediatric Autoimmune Neuropsychiatric Disorders associated with Streptococcus (PANDAS) present as an acute onset of Obsessive Compulsive Disorder (OCD) in children.

Research led by Susan Swedo resulted in a publication in the American Journal of Psychiatry in 1998 (Swedo, Leonard, Garvey, Mittleman, Allen, et al. Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections: clinical description of the first 50 cases. Am J Psychiatry 155: 264-271)

There are 5 criteria for the diagnosis of PANDAS:

• Acute onset and episodic relapses of OCD and/or tic disorder;
• Onset before puberty;
• Association with Group A Streptococcal infection;
• Symptom onset or aggravation; and
• Association with neurological abnormalities, such as motor hyperactivity or abnormal movements.

Treatment involves immune regulation and antibiotic prophylaxis.  Further work has led to the development of a concept, called Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS) with a more acute onset of symptoms and not related to any particular infection.

The criteria for PANS would include:

Abrupt, dramatic onset of Obsessive-Compulsive Disorder or severely restricted food intake

Concurrent presence of additional neuropsychiatric symptoms, with similarly severe and acute onset, from at least two of the following seven categories (see text for full description):

• Anxiety
• Emotional lability and/or depression
• Irritability, aggression and/or severely oppositional behaviours
• Behavioural (developmental) regression
• Deterioration in school performance
• Sensory or motor abnormalities
• Somatic signs and symptoms, including sleep disturbances, enuresis or urinary frequency
• Symptoms are not better explained by a known neurologic or medical disorder, such as Sydenham Chorea, Systemic Lupus Erythematosus, Tourette Disorder or others.

Note: The diagnostic work-up of patients suspected of PANS must be comprehensive enough to rule out these and other relevant disorders.  The nature of the co-occurring symptoms will dictate the necessary assessments, which may include an MRI scan, lumbar puncture, electroencephalogram or other diagnostic tests.  (From Research Subgroup to Clinical Syndrome: Modifying the PANDAS Criteria to Describe PANS (Pediatric Acute-Onset Neuropsychiatric Syndrome: Susan E. Swedo, James F. Leckman and Noel R. Rose)