Genetic epilepsy-digging in for gold: a case series on diagnostic genetic testing in epilepsy
Keywords:Genetics, Epilepsy, Developmental and epileptic encephalopathy
Developmental epileptic encephalopathy (DEE) is a group of ictal and interictal epileptiform disorders (clinical and encephalographic) associated with severe cognitive and behavioural impairments according to the classification and terminology criteria of the international league against epilepsy (ILAE). Less than half of the genetic etiologies have been identified, even though DEEs are genetically heterogenous. Hence, genetic diagnoses of childhood neurological disorders are important as well as challenging. This research aims at determining the diagnostic utility of genetic testing (whole exome sequencing) in heterogeneous group of childhood DEEs. Here, we present the case series of 5 children who have had at least 1 episode of seizure during their lifetime associated with developmental delay and a definite genetic etiology. In view of an unrecognised aetiology, parents were counselled for a genetic evaluation. Genetic test reports showed pathogenic gene variation for epilepsy. Even though intervention would be mostly be the same, genetic aetiology helped us in prognosticating and improving the family’s outlook towards the disease condition. Hence it is desirable to identify genetic variations in all possible childhood epilepsy cases as it has the potential to improve family planning, aid the prognosis, and start specific interventions and also helps to save time in selecting appropriate anti-epileptic drugs.
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