Mild COVID-19 Infection in a Patient with Multiple Sclerosis, while Taking Fingolimod: A Case Report

Background: Fingolimod, as an immunosuppressive drug, is used in the treatment of patients with Multiple Sclerosis. During recent pandemic, several controversies raised to stop or continue immunosuppressive drugs such as fingolimod in patients who developed coronavirus disease 2019. In this regard, most of consensuses advised to stop the consumption of this drug, but try to re-initiate before 6-8 weeks to prevent the disease’s activity or occurrence of rebound phenomenon. Case presentation: we report a 40-year old female patient with Multiple Sclerosis receiving fingolimod. Having peripheral lymphopenia, she developed coronavirus disease 2019 symptoms, tested for polymerase chain reaction of coronavirus, and the result was positive. Afterward, she stayed at home and did not stop fingolimod. However, her symptoms have improved and she did not need hospitalization for the entire course of coronavirus disease 2019 infection. Conclusion: The effects of the treatment with fingolimod on a patient infected by coronavirus disease 2019 are complex. On one hand, fingolimod withdrawal can increase the number of circulating lymphocytes, which consequently improves body defense against viral infections. On the other hand, it can also increase the risk of cytokine storm, which could be harmful. Therefore, further studies needed to find the risks and beneficial effects of fingolimod on coronavirus disease 2019 patients.