MYOCLONIC-ASTATIC EPILEPSY (DOOSE SYNDROME)

Introduction

Myoclonic-Astatic Epilepsy (MAE), also known as Doose Syndrome is a pediatric seizure disorder commonly affecting children between the ages of 2-5 years that is characterized by frequent myoclonic and atonic seizures. MAE often presents with developmental delay, cognitive impairment, and behavioral challenges.

MAE affects males more often than females at a ratio of 2:1 after the first year of life. During the first year of life literature suggests that MAE will affect the sexes at roughly the same rate.

Signs & Symptoms

Epilepsy

MAE’s hallmark symptoms are frequent myoclonic and atonic seizures, however it is not uncommon for other seizure types to be witnessed in patients with MAE. Other seizures may include generalized tonic-clonic, absence, tonic, and progression to non-convulsive status epilepticus (NCSE). Patients can have hundreds of seizures in a single day, and most frequently have seizures in the morning shortly after waking. Sometimes these seizures are isolated, but they often tend to cluster thus increasing their risk to slip into status-epilepticus.

EEG in MAE typically reveals bursts of 2-5 Hz polyspike and wave complexes that are generally superimposed onto otherwise normal looking backgrounds. An important feature in differentiating MAE from other pediatric seizure disorders like LGS is the presence of a relatively normal PDR and sleep architecture.

Cognitive Impairment

Cognitive outcomes in MAE are highly variable. Some experience normal cognition while others may have severe intellectual disability. The literature suggests that seizure frequency is correlated to the cognitive outcome as those who attain freedom from seizures tend to have more favorable cognitive outcomes. Changes in behavior are another commonly associated symptom with MAE. Up to 1/5th of documented MAE cases are diagnosed with ADHD.

Treatment & Prognosis

Treatment efficacy of MAE varies as some enter complete remission of seizures, and others have intractable epilepsy. MAE is largely considered a generalized seizure disorder and is treated as such with ethosuximide which is a common AED for controlling generalized seizures. The standard of care is to pair the AED’s with dietary therapy which most often consists of the ketogenic diet.

Prognosis in MAE varies depending on the age of onset, frequency of seizures, and seizure control. The literature suggests that roughly 3 in 5 children will have a complete remission from seizures and no longer require treatment. In other children, seizure control may range from well controlled to intractable. In children who do not have seizure freedom, cognitive impairment tends to increase in severity.