By: Catherine Joachin
What is the Lennox-Gastaut Syndrome?
Lennox-Gastaut syndrome (LGS) is a severe form of childhood-onset epilepsy. People with this condition can experience various types of seizures, sustain lifelong brain damage, and suffer from significant cognitive problems, which can be aggravated by seizure activity and other genetic, developmental, or other factors (Child Neurology Foundation, 2022).
Symptoms and Causes
People with Lennox-Gastaut syndrome often face a range of intellectual difficulties, behavioral issues, and developmental delays. These problems, which can worsen over time, include learning disorders, poor social skills, mood instability, personality disturbances, aggressiveness, and psychomotor difficulties (Cincinnati Children’s, 2022). Children with Lennox-Gastaut syndrome may also exhibit signs similar to those observed in people with autism spectrum disorder (Cleveland Clinic, n.d.).
There are many conditions associated with Lennox-Gastaut syndrome, including:
• Congenital brain malformations
• Traumatic brain injuries
• Brain infections
• Low oxygen supply to the brain (cerebral hypoxia)
• Tuberous sclerosis
• Brain tumours
• Inherited genetic, metabolic or degenerative conditions
(Cleveland Clinic, n.d.; National Institute of Neurological Disorders and Stroke, n.d.)
De novo mutations and West syndrome can also lead to the development of Lennox-Gastaut syndrome; however, 25% of all LGS cases do not have an identifiable cause (Cleveland Clinic, n.d.).
Types of seizures
Individuals with Lennox-Gastaut syndrome can experience clusters of seizures and/or status epilepticus, a particularly dangerous and potentially fatal medical condition where seizures either last too long or occur in alarmingly rapid succession (Cleveland Clinic, n.d.). This seizure profile can give rise to periods of frequent seizures separated by short seizure-free periods
(NINDS, n.d.).
The most common seizure types include tonic, atypical absence, atonic, myoclonic, focal, and generalized tonic-clonic seizures (Child Neurology Foundation, 2022.; Cincinnati Children’s, 2022).
Tonic seizures are marked by a sudden stiffening of muscles (Cleveland Clinic, n.d.). These typically occur during sleep but may cause a person to fall if they happen during the day (Child Neurology Foundation, 2022).
Atypical absence seizures are characterized by a brief loss of consciousness along with repetitive eye and mouth movements (Cleveland Clinic, n.d.). These staring spells are often mistaken for daydreaming, a lack of attention, or absentmindedness (Cleveland Clinic, n.d.).
Atonic seizures involve a sudden loss of muscle tone, which can cause people to drop to the ground (Cincinnati Children’s, 2022). This lack of muscle control prevents people from
protecting important body parts from an eminent fall, possibly resulting in life-threatening injuries (Child Neurology Foundation, 2022).
Myoclonic seizures consist of brief, involuntary muscle spasms (Cleveland Clinic, n.d.).
Focal seizures originate in a specific brain area (lobe) and can affect sensory, motor, or other areas of functioning (Cleveland Clinic, n.d.). These may progress into full-body convulsions (Cincinnati Children’s, 2022).
Tonic-clonic seizures combine periods of body stiffening with periods of rhythmic jerking and can last several minutes (Cleveland Clinic, n.d.).
Diagnosis
Lennox-Gastaut syndrome is a rare condition. It predominantly targets males and affects around 2% of the epilepsy community, which is equivalent to 1-2 individuals out of every million (Cleveland Clinic, n.d.). Signs usually begin to appear in early childhood, around ages 3 to 5 (Cleveland Clinic, n.d.).
This condition can be diagnosed with the help of imaging technology, electroencephalograms (EEG), laboratory testing, and genetic testing (Cleveland Clinic, n.d.). By using an EEG, it is possible to detect a pattern of brain electrical activity that is unique to those with Lennox Gastaut syndrome (NINDS, 2023).
Treatment and Management
Lennox-Gastaut syndrome can be challenging to treat. As a result of its drug resistance, patients affected by this condition may rely on multiple forms of anticonvulsant medications to manage their seizures (Cleveland Clinic, n.d.). Other treatment options include dietary therapies, brain surgery and implanted devices. Vagus nerve stimulation (VNS) and corpus callosotomy, a surgical procedure concerned with severing the connection between the two brain hemispheres, are notorious strategies in seizure management (Cincinnati Children’s, 2022).
Drugs and non-pharmacological treatments can be used in tandem to optimize quality of life; however, current research on best practice strategies recommends adopting a personalized approach to treatment due to the complex and diverse nature of Lennox-Gastaut syndrome (Strzelczyk & Schubert-Bass, 2021).
Conclusion
Lennox-Gastaut syndrome is a rare type of drug-resistant epilepsy that appears in early life. Multiple seizure types, cognitive impairment, behavioral disturbances, and abnormal EEG activity are hallmarks of this disorder. While there is no cure for this condition, research continues to expand treatment options.
Resources:
Child Neurology Foundation. (2022). Lennox-Gastaut Syndrome – Child Neurology Foundation. https://www.childneurologyfoundation.org/disorder/lennox-gastaut-syndrome/
Cincinnati Children’s Hospital Medical Center. (2022). Lennox-Gastaut Syndrome | Symptoms, Diagnosis and Treatment. https://www.cincinnatichildrens.org/health/l/lennox-gastaut-syndrome\
Cleveland Clinic. (n.d.). Lennox-Gastaut Syndrome (LGS). Cleveland Clinic. https:// my.clevelandclinic.org/health/diseases/23171-lennox-gastaut-syndrome-lgs#overview
National Institute of Neurological Disorders and Stroke. (2023). Lennox-Gastaut Syndrome. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/health information/disorders/lennox-gastaut-syndrome
Strzelczyk, A., & Schubert-Bast, S. (2021). Expanding the Treatment Landscape for Lennox-Gastaut Syndrome: Current and Future Strategies. CNS Drugs, 35(1), 61-83. https://doi.org/10.1007/s40263-020-00784-8
