Abstracts

Rationale: Epilepsy is frequent in children with Down syndrome (DS). Seizures are usually responsive to medical treatment; status epilepticus (SE) is uncommon in this syndrome. SE is a common neurological emergency; super-refractory SE is defined as seizures that continue or recur 24 hours or more after initiation of anesthetic therapy, and is usually associated with severe brain insult. New onset refractory status epilepticus is described as SE of unclear etiology that is highly refractory to standard first- and second-line therapeutic agents. Ketogenic diet (KD) is an alternative treatment to refractory epilepsy and consists in a high-fat, adequate protein and low-carbohydrate diet. The metabolic pathway is modified from glucose to ketone as source of cerebral energy. Ketone bodies improve seizure control, although the mechanism is not clearly understood. In SE, especially in children, KD has shown good results. We report a case of a child with DS and no previous history of epilepsy, who developed an episode of new onset super-refractory tonic SE, improved after institution of KD. We describe the clinical characteristics in this case and the EEG evolution, during treatment with various antiepileptic drugs (AEDs) and KD. Methods: Case report. Results: A three-year-old boy, with DS diagnosed at birth, had acute myeloid leukemia (AML) diagnosed at eighteen months of age, treated with chemotherapeutic agents until six months before admission; AML was in remission. There was no previous history of epilepsy or epileptic seizures. Two weeks before admission the patient had a brief tonic seizure. On the day of admission he had recurrent tonic seizures, which lasted for approximately four hours. Continuous EEG monitoring (cEEG), initiated on admission, revealed tonic status epilepticus. Brain MRI and cerebral spinal fluid were normal. The child was treated with several therapeutic regimens including midazolam, phenobarbital, phenytoin, pyridoxine, topiramate and clobazam; the dosing of each drug is shown in Table 1. Despite all AEDs, EEG showed persistent electrographic seizures. Intravenous thiopental was initiated and titrated to 120 mg/kg/h. After 48 hours at this dosing scheme, cEEG showed quasi-continuous epileptiform discharges and very frequent seizures. On hospital day 10, KD was introduced in association to phenobarbital, topiramate and clobazam. KD had a 4:1 ratio and was offered by nasoenteral tube. Ketosis was measured by blood sample and reached 48 hours after the first administration of the diet. Improvement of EEG was identified after ketonemia of 3.6 mmol on day 12 of admission. The patient remained hospitalized for adaptation to KD. Three months after hospital discharge, the patient continues on KD and is seizure-free. Progressive clinical improvement has been noted, although not to the same level prior to the SE. Conclusions: Super-refractory SE constitutes a challenge in terms of treatment. Failure to respond to several AEDs usually predicts a protracted course and a poor outcome. KD is a useful therapeutic option in this setting.