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.