Successful Use of Tocilizumab in a 2‐Year‐Old Girl With Probable C‐ NORSE / FIRES : A Case Report

Background New‐onset refractory status epilepticus (NORSE) is a life‐threatening condition characterized by the acute onset of refractory status epilepticus (RSE) in previously healthy patients, without an identifiable acute or active structural, toxic, or metabolic cause. FIRES is a subcategory of NORSE characterized by a prior febrile infection. Case Report We present a case of a previously healthy 2‐year‐old female, with fever, cognitive alterations, and status epilepticus, with a diagnosis of cryptogenic NORSE (C‐NORSE). Despite treatment with IV steroids, IVIG, plasma exchange, and rituximab, her condition deteriorated. Improvement began after administration of the anti‐IL‐6 receptor antibody IV, tocilizumab, and has remained stable. Conclusions IL‐6 is an important cytokine in the immuno‐inflammatory role of C‐NORSE/FIRES (febrile infection‐related epilepsy syndrome). Therefore, its measurement in cerebrospinal fluid and blockade with anti‐IL‐6 should be considered, especially in patients with severe presentation at diagnosis or refractory to first‐ and second‐line treatment.