Epilepsy associated with chromosomal disorders

Chromosomal disorders are multisystemic conditions frequently presenting developmental delay and epilepsy as primary neurological symptoms. Epilepsy in these syndromes significantly impacts morbidity, quality of life, and neurodevelopment. Angelman syndrome, ring chromosome 20, Down syndrome, Dup15q syndrome, and others display suggestive electroclinical profiles that may help diagnose and treatment. Understanding the associated electroencephalographic (EEG) findings is critical for clinicians to tailor interventions and optimize outcomes. This review highlights the prevalence, onset, seizure types, EEG characteristics, and treatment approaches for epilepsy in major chromosomal disorders. Angelman syndrome features epilepsy with atypical absences and myoclonic seizures, often associated with specific EEG patterns such as rhythmic delta activity. Ring chromosome 20 syndrome presents with focal frontal seizures, including non-convulsive status epilepticus. Down syndrome has a biphasic epilepsy distribution, from infantile spasms to late-onset myoclonic epilepsy. Similarly, Dup15q syndrome is marked by drug-resistant epilepsy, with EEG showing beta rhythms and hypsarrhythmia. Knowing the electroclinical patterns associated with chromosomal disorders may improve diagnosis and epilepsy management, which enhances patient care and prognosis accuracy.