Bortezomib-Responsive Refractory Anti-N-Methyl-d-Aspartate Receptor Encephalitis

Abstract

Background: Anti-N-methyl-d-aspartate receptor encephalitis is a central nervous system inflammatory autoimmune disease affecting adults and children. The use of first- and second-line immunotherapies is supported. Recent reports suggest the efficacy of bortezomib in severe anti-N-methyl-d-aspartate encephalitis in adult patients not responsive to second-line treatment; there are no data about pediatric patients.

Patient description: We describe an eight-year-old child with anti-N-methyl-d-aspartate encephalitis not responsive to first- and second-line treatments who experienced marked clinical improvement after bortezomib administration.

Discussion: Bortezomib is a selective and reversible inhibitor of the 26S proteasome, which is used to treat oncologic and rare autoimmune disorders in pediatric patients. As observed in adult patients, bortezomib administration induced anti-N-methyl-d-aspartate antibody titer decline and clinical improvement with an acceptable risk profile.

Conclusion: This is the first report of the use of bortezomib in children with anti-N-methyl-d-aspartate encephalitis; it could be a useful therapeutic option in children with refractory anti-N-methyl-d-aspartate encephalitis.

Keywords: Anti-N-methyl-d-aspartate receptor (NMDAR) antibodies; Arterial spin labeling (ASL); Autoimmune encephalitis; Cell-based assay; Immunosuppressive therapy; Proteasome inhibitor; Refractory status epilepticus.