Neuropsychiatric symptoms following sore throat in a young boy

A previously healthy 6-year-old boy was referred to us by his primary provider, with a history of sudden onset behavioural abnormalities including irritability, sleep disturbance and anxiety. Physical examination revealed no significant findings; further analyses were not suggestive of meningitis, encephalitis, metabolic abnormalities, toxicity or any other obvious cause. On rechecking the patient's history, an episode of throat pain 1 week prior to the symptom onset was noted. Therefore, the possibility of paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) was considered. The antistreptolysin O titre was high (1078 IU/mL), and it increased to 1194 IU/mL 4 weeks later, leading to a diagnosis of PANDAS. He was started on ampicillin and administered one dose of intravenous immunoglobulin. His abnormal behaviours subsided and he returned to a normal state within 48 hours of treatment. This report aims to provide insights into the symptomology and diagnosis of PANDAS in children.