Intrathecal treatment of anti-N-Methyl-D-aspartate receptor encephalitis in children.

Anti-NDMA receptor (NMDAR) encephalitis is an auto-immune condition. There is no uniformly agreed treatment strategy for the disorder in children. We report the use of intrathecal treatment with methotrexate and methylprednisolone in three children (one male, two females, age 10y, 11y, and 14y) with anti-NMDAR encephalitis, who did not respond to steroids, plasmapheresis, or rituximab. There was significant clinical improvement and stabilization of the anti-NMDAR antibody titers in cerebrospinal fluid (CSF) and blood in two patients. In the third patient, although anti-NMDAR antibody titers in CSF decreased, clinical recovery was less satisfactory. Intrathecal treatment with methotrexate and methylprednisolone seems to be a promising alternative treatment for some paediatric cases of resistant anti-NMDAR encephalitis.