The characterization of psychosis and response to antipsychotic therapy in monogenic forms of familial focal epilepsy: A systematic review.

While the genetic architecture of epilepsy is complex and presumably polygenic in many cases, pathogenic variants have increasingly been identified, and this is perhaps best exemplified by the monogenic familial focal epilepsies. Although individuals with epilepsy (particularly focal epilepsy) are at increased risk of developing psychosis, little has been written on this topic in relation to monogenic familial focal epilepsy, specifically. As such, this systematic review aimed to characterize the phenomenology of psychosis (and response to antipsychotic therapy) in affected individuals. Only eight articles were identified and minimal information with respect to psychiatric phenotyping was provided in most cases. As such, although no firm conclusions can be drawn, it is notable that none of the reports described a temporal relationship between seizure and psychosis onset; the typical convention used in epilepsy. As most reports also did not include primary psychotic disorder diagnoses, it remains unclear if the individuals' presentations were understood to represent epileptic psychoses or schizophrenia, and to what degree (if at all) their genetic variants were thought to have contributed directly to psychosis risk. More robust case descriptions are needed to better characterize the nature of psychotic symptoms (and their response to treatment) in monogenic familial focal epilepsy.