Most pediatric cases of neuromyelitis optica spectrum disorder (NMOSD) differed from adult cases due to antibody destruction of myelin oligodendrocyte glycoproteins (MOGs) as opposed to anti-aquaporin-4 (AQP4) autoantibodies, according to results from a study published in Multiple Sclerosis and Related Disorders.
Both AQP4 and MOG antibodies necessitated the constant implementation of immunosuppressive treatments to improve patient prognosis. Investigators conducted this multicenter study in the Portuguese NMOSD registry from January 1, 2018, to December 31, 2019.
Using available clinical data from the registry, the researchers classified each patient as either anti-AQP4 positive, anti-MOG positive, or double seronegative for both antibodies. The researchers identified 180 individuals with NMOSD, including 20 pediatric (<18 years) patients.
Of these 20 pediatric patients, 65% (13 of 20) demonstrated anti-MOG antibodies, 30% (6 of 20) exhibited anti-AQP4 antibodies, and 5% (1 of 20) was seronegative for both antibodies. NMOSD manifested as monofocal (60%) and multifocal (40%) in these 20 patients.
Read more about NMOSD differential diagnosis
Most pediatric patients exhibited monophasic NMOSD, 7 with (53.8%) anti-MOG, and 1 with (16.7%) anti-AQP4. Lumbar punctures in 16 of the 20 patients revealed cerebrospinal fluid (CSF) pleocytosis in 9 (45%) patients and CSF-specific oligoclonal bands in 4 (20%) patients all of whom had anti-MOG antibodies.
During relapses, all pediatric patients underwent intravenous methylprednisolone therapy. Half of these patients also underwent intravenous human immunoglobulin G therapy, while 20% underwent plasma exchange. Follow-up treatment included oral prednisolone in 30% of patients, rituximab in 30%, and azathioprine in 25%.
At the time of final data collection for the study, 5 patients with anti-MOG positive (38.5%) and 5 with anti-AQP4 positive (83.3%) still received maintenance immunosuppressive therapy, while 1 anti-AQP4 had discontinued long-term immunosuppression due to a long duration of remission. One individual with anti-AQP4 positive and additional comorbidities had died due to complications during a relapse involving the brainstem.
“Given the implicated morbidity and mortality, it remains relevant to study pediatric NMOSD to quickly establish the diagnosis and initiate appropriate therapy, stabilizing the disease, reducing the occurrence of relapses, and improving prognosis,” the authors concluded.
Martins C, Moura J, Figueiroa S, et al. Pediatric neuromyelitis optica spectrum disorders in Portugal: a multicentre retrospective study. Mult Scler Relat Disord. 2022. doi:10.1016/j.msard.2022.103531