A previously healthy 7-year-old boy suddenly started blinking, grimacing, and jerking his head about every 10 seconds. Uncharacteristically, he hardly sat still and had a tantrum. Ten days after this abrupt onset of tics, hyperactivity, and emotional lability, his parents took him to the emergency department. The day before the symptoms had started, his primary care physician (PCP) had diagnosed group A streptococcal (GAS) pharyngitis and began treatment with an antibiotic (cefdinir). The PCP also screened the family, which revealed GAS infection in the father and brother.
Physical and laboratory examinations in the ED were unremarkable. The consulting pediatric neurologist diagnosed transient tic disorder and, considering the recent streptococcal infection and the boy’s sudden status change, ordered an MRI scan and referred him to the pediatric acute-onset neuropsychiatric syndrome (PANS) clinic.