Pediatric Autoimmune Neuropsychiatric Disorders Associated With Streptococcal Infections (PANDAS)

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) involve the sudden onset of neuropsychiatric symptoms, including obsessions, compulsions, and various tics. These conditions are characterized by the rapid development of severe behavioral symptoms in children triggered by infections, particularly streptococcal infections. PANDAS is a rare autoimmune disorder that was first described in 1998 by Swedo et al, and is characterized by the sudden onset of obsessive-compulsive or tic disorder symptoms following group A streptococcus infection. PANDAS is typically diagnosed in certain pediatric and prepubertal populations who have had a recent or currently have a group A beta-hemolytic streptococcus infection.  PANDAS was initially categorized under postinfectious syndromes and defined as pediatric infection-triggered autoimmune neuropsychiatric disorders. Later, in 2010, these disorders were reclassified as pediatric acute-onset neuropsychiatric syndromes (PANS). PANS encompass acute-onset cases with obsessions, compulsions, and heterogeneous tics not solely triggered by infections but by other factors (eg, environmental factors, emotional stress, or exposure to oxidative toxins). PANS may involve severe eating restrictions in addition to at least 2 severe neuropsychiatric symptoms, including choreiform movements, sensory disturbances, and even hallucinations. PANS may also include somatic symptoms, ranging from sleep-related motor disruptions to mydriasis, enuresis, and urinary dysfunction. The classification of PANDAS and PANS as distinct clinical entities is debated. Some theories suggest that PANDAS may be a variant of Sydenham chorea due to overlapping features and genetic predispositions.  Physical symptoms of PANDAS can include tics, sensitivity to sensory inputs, motor skill deterioration, sleep disorders, and joint pain;  psychological symptoms can encompass obsessive-compulsive behaviors, anxiety, emotional lability, developmental regression, and depression. The diagnosis of PANDAS relies on clinical criteria, including the presence of obsessive-compulsive disorders or tic disorders, sudden onset of symptoms in childhood, episodic symptom course, association with streptococcal infection, and neurological abnormalities. Despite being a diagnosis of exclusion, prompt identification and management are crucial for patient outcomes. Comprehensive diagnostic evaluation includes psychoneurological assessments, infectious disease testing, autoimmune and endocrine evaluations, imaging, and genetic tests.  Confirmation of streptococcal infection involves throat cultures and antibody tests, though these are not definitive markers for PANDAS. Neuroimaging in PANDAS patients often reveals basal ganglia abnormalities and can help distinguish PANDAS from other conditions. Treatment primarily involves antibiotics to address streptococcal infections, with β-lactams and macrolides being common choices. These antibiotics also have immunomodulatory, neuroprotective, and anti-inflammatory properties. Antibiotic prophylaxis and potential vaccinations against streptococcal infections are also being explored to prevent recurrence and manage symptoms. Overall, understanding the epidemiology, neuropathophysiology, diagnosis, and treatment of PANDAS is essential for improving patient care and outcomes in this rare and complex condition.