Abstracts

Rationale: Patients with refractory epilepsy typically undergo serial trials of medications in various combinations. In published clinical trials the reported rate of seizure freedom for a three month treatment period upon adding a new drug is only a few percent. Long term remission in highly refractory patients is rarely reported. Methods: We report a 38 year old caucasian female, followed at UCSD Epilepsy Center from 1994 to present. Her epilepsy began shortly after a coup-contracoup head injury from a horseriding accident at age 20. Post injury head CT showed bilateral temporal contusions; subsequent MRI showed encephalomalacia in the right lateral temporal cortex. Comprehensive workup for epilepy surgery included Video-EEG with scalp and intracranial electrodes, revealing bilateral independent seizure onsets with distinctive features in right and left temporal seizures. Medication trials included gabapentin, carbamazepine, oxcarbazepine, phenobarbital, vigabatrin (in clinical trial), acetazolamide, zonisamide, valproic acid, primidone, phenytoin, lamotrigine, levetiracetam in various combinations. She had Vagus Nerve Stimulator (VNS) implanted in 2001 with a battery replacement in 2008. Small adjustments in stimulation parameters were made several times per year. Despite up to 4 drugs and VNS, her seizure calendars consistently showed 40 or more simple and complex partial seizures per month, for over a decade. Due to chronic hyponatremia and chronic leukopenia (with adequate neutrophils) her epileptologist tapered her off oxcarbazepine and onto pregabalin in late 2008. By Jan 2009, she took pregabalin 600 mg and remained on levetiracetam 3000 mg, topiramate 200 mg and clonazepam 3 mg daily in 4 divided doses. Results: Within weeks of the conversion, the patient noted remission of seizures. At her next visit, the CBC revealed stable leukopenia with new neutropenia and absolute neutrophil counts(ANC)of 200-400. She is followed by both a community and university hematologist with a working diagnosis of autoimmune neutropenia. The patient remains healthy despite chronic low ANC. The pregabalin dose has been gradually decreased from 600 mg to 200 mg daily, with continued seizure remission and continued neutropenia. An emergency appendectomy in May 2010 was associated with transient elevation of ANC to >600, which fell quickly postoperatively, but no seizures. Conclusions: This case provides reassurance that patients with longstanding refractory epilepsy may enter stable remission during continued rotation of drugs in variable combinations, along with VNS. However, we cannot ignore the potential role of neutropenia, which emerged co-incident with remission. While the cause of neutropenia remains under investigation, this observation supports the hypothesis that inflammation may contribute to epileptogenesis (Vezzani et al., 2005, 2008; Choi and Ko, 2008). After 15 years of epilepsy refractory to polypharmacy and VNS, her remission continues at 18 months, and her ANC remains <500. Additional similar cases are sought to further explore this relationship.