DISCUTION AND CONCLUSION
Epilepsy and EEG abnormalities are frequently reported in KBG patients.
Most often present with generalized or combined generalized and focal
epilepsy with onset in childhood. Literature data are limited,
incomplete, and inconclusive to identify a specific electroclinical
pattern. Various seizure types have been reported in the literature,
with tonic-clonic generalized seizures being the most frequent seizure
types. Focal seizures are also rarely noted. Moreover, many cases of
generalized and focal EEG abnormalities without clinically evident
seizures have been reported. In most of the KBG syndrome patients with
epilepsy, seizures are drug-resistant. Moreover, epilepsy in patients
with KBG syndrome is associated with poorer developmental outcomes.
We report a boy presenting with a drug-resistant, monogenic epilepsy
syndrome, due to ANKRD11 pathogenic de novo variant found by TES
associated with the KGB syndrome. This variant has never been reported
so far in the literature. The reassessment of phenotypic features
confirmed that he fulfilled the proposed diagnostic criteria for KBG
syndrome.
We outline the electroclinical pattern of epilepsy in KBGs, types of the
epileptic seizures and EEG features of this patient. He suffered from
focal to tonic-clonic seizures, treated with various AEDs, making a
drug-resistant epilepsy diagnosis. Even though our result cannot be
conclusive, we hypothesize that the represented EEG pattern together
with the epilepsy and seizure type, dysmorphic facial features, ID, and
behavioral disorders, may help to characterize the phenotype of KBG
syndrome. Future studies regarding these issues may outline the
electroclinical pattern in a larger series of patients with KBG
syndrome.