Abstracts

Rationale: Status epilepticus (SE) is one of the most common neurologic emergencies occurring in about 200,000 patients yearly. One third of SE cases are refractory to treatment with first and second line drugs and are associated with a high mortality rate. Refractory SE is often correlated with encephalitis, metabolic encephalopathy, and anoxic injury. Rarely no cause for SE is ever found. Patients can be artificially supported for many weeks while multiple treatment modalities are attempted. We present four cases of a newly described syndrome of de novo refractory SE without an identified etiology with pathological correlation.Methods: The Mayo Clinic Arizona EEG database was reviewed from 2002 to 2006 for SE tracings, as all patients with known SE had EEG to confirm the diagnosis and were subsequently monitored. Patients with refractory SE requiring medication induced coma lasting more than 1 week were extracted from the database. Demographic variables included length of SE, video EEG, lab results, therapeutic trials, history of previous epilepsy, pathology, and final outcome.Results: Four cases of patients in refractory SE were found. All patients were female and ages ranged from 20 to 41 years old (mean 28.75). These patients had a preceding flu-like illness associated with behavioral changes one to two weeks prior to presentation. All past medical histories were negative for any risk factors for SE. Three of the patients began their seizure activity with generalized tonic-clonic seizures, while the other patient had fluctuating responsiveness. The duration of SE ranged from 10 to 56 days (mean 35). Video EEG demonstrated continuous nonfocal seizures or burst suppression. All of the patients were treated with multiple antiepileptic drugs (mean 8), including propofol, topiramate, levetiracetam, and inhalational anesthetics. Two patients had vagal nerve stimulators placed and one had a corpus callosotomy. No patient improved clinically. Magnetic resonance imaging did not reveal any abnormalities. Extensive infectious disease evaluation with cerebrospinal fluid (CSF) analysis yielded nucleated cells from 1 to 27 cells/mcL, and was completely negative for testable bacterial, viral, and fungal organisms. CSF glucose was normal in all patients and CSF protein ranged from 31 to 89 mg/dL. Furthermore, serum studies did not point to any specific etiology either. Two patients were treated empirically for an autoimmune etiology without benefit. All patients died from SE. Postmortem examination of the brain revealed no specific etiology, with only nonspecific changes expected from prolonged SE.Conclusions: These four cases represent a rarely encountered refractory SE, which we termed as malignant SE syndrome. This syndrome effects young female patients and presents insidiously as a flu-like illness progressing in one to two weeks to refractory SE. Empiric treatment for any and all suspected causes and multiple treatments for the SE were completely ineffective with each case having a fatal result. The etiology of SE in these patients has yet to be determined.