COVID-19 infection could trigger central nervous system-driven conditions such as multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) in patients with a susceptible immune system, according to a case series recently published in the journal Neurology and Therapy.
COVID-19 is known to produce neurological complications in a significant percentage of patients, with approximately 30% of patients developing neurological sequelae that can last several months. Furthermore, several studies suggest the virus can cause immune dysregulation leading to autoimmune disease through mechanisms such as molecular mimicry and bystander T-cell activation.
However, direct causality between COVID-19 and autoimmune diseases, such as MS and NMOSD, is yet to be established. Therefore, the authors aimed to report 12 cases of patients with newly diagnosed MS or NMOSD shortly after infection.
Read more about NMOSD epidemiology
All patients in the series presented symptoms between 2 to 6 weeks. All patients were infected during the peak of the Delta variant pandemic, but viral lineage was not established in any of the cases. Patients in the NMOSD group and MS group were diagnosed using the International Panel criteria for the diagnosis of NMOSD and the 2017 McDonald criteria for MS, respectively.
The 2 patients in the NMOSD group were young unvaccinated women that presented with mild COVID-19 symptoms shortly before presenting longitudinally extended transverse myelitis and opsoclonus, respectively. Both were seropositive for aquaporin 4 IgG; baseline levels were not available.
Of the 10 patients in the MS group, 8 were not vaccinated, and 2 received a single dose of the Pfizer-BioNtech vaccine. The median age was 28 years. As in the NMOSD group, most patients experienced mild COVID-19 symptoms, and none were hospitalized. Neurological symptoms were varied and included optics neuritis cerebellar symptoms and partial transverse myelitis.
“Larger studies are needed to make any formal conclusions about the direct association of COVID-19 acute infection and the development of CNS autoimmune disorders,” the authors concluded.
Avila M., Tan Y, Hernandez R, et al. Multiple sclerosis and neuromyelitis optica spectrum disorder: onset following acute COVID-19 infection, a case series. Neurol Ther. Published online November 18, 2022. doi:10.1007/s40120-022-00418-9