Neuromyelitis Optica Spectrum Disorders in Pediatric Patients

Background/Purpose: Neuromyelitis optica (NMO) is a rare inflammatory disorder of the central nervous system (CNS), characterized by recurrent optic neuritis (ON) and transverse myelitis (TM). Pediatric patients often show other affected areas in the CNS, such as postrema, diencephalon, or brainstem. In adult patients, up to 75% present with antibodies against aquaporin-4 (AQP4-ab) in the serum. These findings resulted in a revision of previous diagnostic criteria and led to the new unifying term NMO spectrum disorders (NMOSD). In AQP4-ab-naive patients, antibodies against myelin oligodendrocyte glycoprotein (MOG) could be found. These have fewer and less severe episodes and convalesce faster. For patients with AQP4-ab-positive NMOSD, a subsequent immunosuppression is recommended; in MOG-ab-positive cases, only acute treatment is indicated.

Methods: Beginning March 1, 2017, all newly diagnosed patients with NMOSD are included by the Surveillance Unit for Rare Pediatric Disorders (ESPED) in our study for 2 years. Primary study goal is to assess the incidence of NMOSD in children and teenagers younger than 18 years in Germany. Clinical courses, laboratory parameters (e.g., antibody status), and initial therapeutic regimens and their effects are going to be evaluated.

Results: Our recent observations showed that children and teenagers with AQP4-ab-positive NMOSD have more severe and frequent episodes and a prolonged convalescence compared with MOG-ab-positive patients. Current therapeutic recommendations, regarding immunosuppression in case of AQP4-ab seropositivity, seem reasonable.

Conclusion: Still, longer observation periods are necessary, to better predict the clinical courses of NMOSD with/without AQP4-ab; the next step is going to be our project.