What is Lennox–Gastaut Syndrome?

Lennox–Gastaut syndrome (LGS) is a rare and severe form of epilepsy that begins in childhood. It belongs to the group of severe infantile epileptic syndrome (neonatal epileptic encephalopathy with suppression-burst, West syndrome, severe myoclonic epilepsy of infancy). Affected children experience several different types of seizures, most commonly atonic, tonic and atypical absence seizures but generalized tonic-clonic and partial seizures can occur as well.

Three main criteria that define LGS are Multiple seizure types, mainly generalized, Abnormal electroencephalogram (EEG) with generalized slow spike-and-wave discharges (SSW) at <2.5 Hz, Mental retardation, or learning disabilities. People with lgs insight begin having frequent seizures in early childhood, usually between ages 3 and 5. LGS is also a physically dangerous epilepsy syndrome of childhood because of the frequent falls, injuries, and cognitive impairment that can severely limit the quality of life. Children affected might previously have infantile spasms or underlying brain disorder, but etiology can be idiopathic also.

In general, the causes of LGS are divided into two broader groups; Identifiable causes, cryptogenic (non-identifiable) causes. Identifiable causes include brain damage (e.g., head trauma), perinatal complications (e.g., birth asphyxia, intrauterine growth retardation, kernicterus), congenital central nervous system malformations (e.g., tuberous sclerosis), infections (e.g., meningitis, sepsis), or metabolic disorders.

Although EEG features are central to an accurate diagnosis of LGS, it is imperative to consider that they can take time to develop, particularly in young children. The SSW EEG pattern might not be present, initially, in patients who transform to LGS from another epilepsy syndrome, such as West syndrome. Therefore, for patients presenting with the seizure types associated with LGS, particularly tonic or atonic seizures, clinicians should be alert to the possibility of an LGS diagnosis and proactively monitor for EEG abnormalities to confirm its diagnosis.

Several key investigations are recommended for the difficulties mentioned above that are associated with diagnosed LGS. While many underlying causes are still elusive, understanding specific rare variations of epilepsy has recently enabled developers to test novel mechanisms in high-need patient populations like LGS. Currently, the AEDs available for LGS are symptomatic drugs, used to treat the symptom “epilepsy” itself, but not to modify the natural history of the disease that so severely affects the patients’ QoL. The challenge for the near future will be to guide therapeutic choices based on etiology.