Association between Dravet syndrome and Catatonia: a case report

Abstract

Catatonia is a neurobehavioral and motor syndrome that can occur in persons with epilepsy (PWE), though it is rarely described in individuals with developmental and genetic epilepsies such as Dravet syndrome. This case report describes a young adult with Dravet syndrome who developed catatonia after improving seizure control. In this report we explore forced normalization (FN) as a potential mediating mechanism. An 18-year-old male with Dravet syndrome experienced significant seizure reduction after zonisamide was added to his antiseizure regimen. Within two weeks, he developed catatonic features, including mutism, catalepsy, and psychomotor retardation. Bush Francis Catatonia Rating Scale (BFCRS) scores ranged from 17 to 22. Catatonia improved with lorazepam, though seizure frequency increased after zonisamide taper. He later experienced a decline in both neurological and psychiatric function following status epilepticus. EEG was not performed at the time of symptom onset, which limits the ability to diagnose this patient with FN. However, the clinical criteria for FN were partially met, and the timing of zonisamide initiation and catatonia emergence supports its consideration. Non-convulsive status epilepticus (NCSE) remains a plausible alternative mechanism for the catatonia seen in this patient, particularly in those with developmental encephalopathies. This case demonstrates an interesting temporal relationship between improved seizure control and emergence of catatonia in a patient with genetic epilepsy. Further research is required to clarify the relationship between catatonia and FN in epilepsy.