Refractory epilepsy in a patient with Doose syndrome: favorable response after add-on therapy with bromide

Case Report: Potassium bromide (Br) is only used in a few countries mainly for patients with severe myoclonic epilepsy in infancy/Dravet syndrome.

We present a report on an 11-year-old male patient suffering from a 7-year-lasting MAE, who became seizure free under Br for at least 2 years. He developed normally until onset of epilepsy at the age of 3 years. Main seizure types: myoclonic seizures, drop attacks, and grand-mal seizures. EEG: generalized epileptic discharges and seizure patterns. MRI: metabolic diagnostic and molecular genetic testing for SCN1A mutation was negative. Seizures were uncontrolled by sequential monotherapies and combination therapies. Before starting Br, the patient had been treated with 15 antiepileptic drugs, steroids, ketogenic diet, and intravenous immunoglobulins.

In a situation with multiple seizures a day, Br was added to felbamate (FBM), ethosuximide (ESM), and acetazolamide (AZA) as an individual intention-to-treat. We started Br at the age of 9 and increased the dose until up to 1350 mg/d (64 mg/kg/d) within 5 months.

After 4 months the patient showed a significant seizure reduction and became seizure free in the following weeks. After 5 months of treatment a speech disturbance occurred, which disappeared after discontinuation of FBM and ESM and a slight dose reduction of Br to 1275 mg/d, which is still continued until now. We observed no further side effects. AZA is still continued in a low dose. EEG showed a completely remission.

Significant long-lasting (2 years now) improvement of seizure situation as well as of cognition and participation was achieved after starting Br as an add-on therapy. In the first months after introduction of Br, a speech disorder occurred, which disappeared after discontinuation of FBM and ESM and a slight dose reduction of Br. Reduction of seizure frequency was achieved not before 4 months after starting Br, in the following weeks completely remission was observed.

Br could show high efficacy in patients with refractory MAE. Therefore, Br could be considered as an option for treating patients with MAE.