Importance: Infantile convulsions and choreoathetosis (ICCA) is a rare neurological disorder. Many affected patients are either misdiagnosed or prescribed multiple antiepileptic drugs.
Objective: To explore therapeutic drug treatments and dosages for ICCA in children.
Methods: Detailed clinical features (e.g., past medical history and family history), genetic features, and treatment outcomes were collected from the records of six patients with ICCA.
Results: Mean age at paroxysmal kinesigenic dyskinesia (PKD) onset was 8 years 8 months (range, 3-12 years); the clinical presentation was characterized by daily short paroxysmal episodes of dystonia/dyskinesia. All patients had infantile convulsions at less than 1 year of age, and the mean onset age was 5.5 months (range, 4-7 months). Two patients had a family history of ICCA, PKD, or benign familial infantile epilepsy. Whole exome sequencing identified the c.649-650insC mutation in PRRT2 in six patients; three mutations were inherited and three were de novo. All patients were prescribed low-dose carbamazepine and showed dramatic improvement with the complete disappearance of dyskinetic episodes after 3 days. They attended follow-up for 5-17 months and were attack-free until the final follow-up.
Interpretation: PRRT2 mutations are the primary cause of ICCA. Low-dose carbamazepine monotherapy is effective and well-tolerated in children.
Keywords: ICCA; PRRT2; Paroxysmal kinesigenic dyskinesia; Treatment.
© 2022 Chinese Medical Association. Pediatric Investigation published by John Wiley & Sons Australia, Ltd on behalf of Futang Research Center of Pediatric Development.