Risk of relapse following COVID-19 or anty-SARSCoV- 2 vaccination in patients with neuromyelitis optica spectrum disorders

ABSTRACT

Neuromyelitis optica spectrum disorders (NMOSD) is an immunemediated inflammatory disorder of the central nervous system. SARS-CoV-2 infections not only affect the lungs but generally all organs including the central nervous system. The underlying pathophysiology for SARS-CoV-2 associated CNS disease is suspected to be immunogenic. Therefore, the question is whether COVID-19 can trigger relapses in NMOSD patients. On the other hand, there have been reports that COVID-19 vaccination may trigger a relapse. The aim of our study was to assess the risk of NMOSD relpase after SARS-CoV-2 infection or after vaccination. Department of Neurology Medical University of Warsaw is a reference center for treatment of NMOSD patients in Poland. Nowadays we are taking care on seventy-five patients meeting NMOSD diagnostic criteria. As of March 31, 2022, we registered 47 SARS-CoV-2 infections. Twenty-two SARS-CoV-2 infections were reported in patients prior to COVID-19 vaccination (19 females, 3 males). Mean age of patients was 49+/-10 years, mean EDSS 4.5+/-1.5. Twenty (90.9%) patients were on immunosuppressive therapy (rituximab -11, steroids-4, inebilizumab -2, azathioprine -1, satralizumab -1, mycophenolate mofetil -1). Twenty-five SARS-CoV-2 infections occurred after the full course of vaccination (23 females, 2 males). Mean age of patients was 50+/-12 years, mean EDSS 3.6+/-1.7. Twenty-three (92%) patients were on immunosuppressive therapy (rituximab - 12, inebilizumab - 1, azathioprine - 3, satralizumab - 3, mycophenolate mofetil - 4). Three patients had a relapse after COVID-19 (within three months). Two of these people were still unvaccinated at the time. These patients were not receiving full immunosuppressive treatment at the time (one patient developed COVID-19 right after the first dose of rituximab, the other patient received the last dose of rituximab 18 months earlier). The third patient was treated with rituximab and was fully vaccinated. NMOSD relapse occurred in 6% of patients confirmed with COVID-19. Thee risk of relapse was even lower (2%) among patients properly treated with immunosuppressants. Of our seventy-five patients, only two were not vaccinated against SARS-CoV-2. All patients receivedmRNA SARS-CoV-2 vaccines. No vaccine-related NMOSD attack has been reported. Conclusion(s) Patients with NMOSD treated with immunosuppressants have a low risk of a relapse due to COVID-19 infection. In our study mRNA COVID-19 vaccines do not increase the risk of a relapse.