Abstracts

Rationale: Status epilepticus is a severe condition caused by disorders affecting the central nervous system in which hypersynchronous epileptic activity lasts longer than the usual duration of isolated self-limited seizures (time t1), causing neuronal damage or alteration of neuronal networks at a certain time point (time t2), depending on the type and duration of status epilepticus. The most common causes of SE observed in the Intensive care unit include stroke, infections, and subtherapeutic levels of anti-seizure medications (ASMs) in patients with epilepsy; a less common cause of SE is autoimmune encephalitis (AE). The management of SE in the context of AE is challenging and combined treatment with immunomodulant treatments (i.e., corticosteroids, IVIG, or plasma exchange), ASMs, and anesthetic drugs is generally required. In this case series, we described the management of 14 patients with autoimmune status epilepticus who presented good outcomes after multidrug treatment without therapy-related side effects.

Methods: 14 patients with ASE were enrolled (mean age of 61). Specific surface and intracellular neuronal antibodies were searched on the cerebrospinal fluid (CSF) as well as the serum through a Cell-Based Assay (CBA). Prognosis at admission was assessed using the STESS and EMSE scales. Effectiveness was evaluated in terms of clinical and EEG characteristics, and safety in terms of effects occurring.

Results: 8 subjects showed a Non-Convulsive Status Epilepticus (NCSE), of which 1 patient was in coma, whereas 6 subjects showed Convulsive Status Epilepticus (CSE) (1 generalized SE, 5 focal SE). According to CSF analysis, most patients had pleocytosis, hyperprotidorrachia, and positive oligoclonal bands, without specific autoantibodies; only twenty-five percent of patients tested positive for NMDR antibodies. All patients received a combined immunomodulant therapy (corticosteroids plus IVIG or plasma exchange) as well as intravenous ASM treatment (mostly sodium channel blockers and anti-glutamatergic drugs) and anesthetic treatment (i.e., propofol, midazolam, and Ketamine). Despite an unfavorable prognosis upon admission (STESS 3/5, EMSE 57/195), 10 patients survived with almost complete stabilization of the EEG recording. Four patients died from conditions unrelated to treatment, such as nosocomial pneumonia, lung cancer, and endocarditis complications. All the complications presented were related to long periods of hospitalization (pneumonia, urinary infection).

Conclusions: SE in the context of AE is a challenge according to the diagnostic and therapeutic approach. The employment of sodium channel blockers and anti-glutamatergic drugs alongside immunomodulant therapies seems to be associated with a good therapeutic outcome. In our experience, mortality was generally correlated to long periods of hospitalization.

Funding: No funding