Introduction
In December 2019, the viral infection outbreak in Wuhan, China became a
global pandemic that crossed borders and put the lives of populations in
danger, especially those with immunodeficiency (1). During these
challenging years and the management of COVID-19 disease, many questions
have arisen regarding immunomodulatory and immunosuppressive therapies,
especially, in patients with demyelinating disease (2). Given the
reduced immune responses, immunodeficient patients are less prone to
develop serious complications of COVID-19 and cytokine storm. However,
they are more likely to develop opportunistic infections that can
mimic the symptoms of SARS-CoV-2 infection (3).
Multiple sclerosis (MS), an autoimmune, demyelinating disease of the
central nervous system (CNS), is mainly linked to the reaction of CD4+ T
cells to the antigens of myelin membrane (4). Two previous randomized
clinical trials (RCTs), has demonstrated that rituximab, a monoclonal
anti-CD20 antibody, could be effective in primary progressive multiple
sclerosis (PPMS) and relapsing-remitting multiple sclerosis (RRMS) (5).
However, there are growing reports, introducing post-rituximab therapy
Pneumocystis jirovecii pneumonia (PJP), in cases of systemic lupus
erythematosus, Wegener’s granulomatosis, rheumatoid arthritis, lymphoma,
and humoral renal transplant rejection (6). Given the fact that
rituximab is a commonly used medication for the highly active forms of
MS, it is important to consider the possible risk of PJP in these
patients.
In the current study, we presented a case of COVID-19 infection, who was
complicated with PJP, following treatment with rituximab for RRMS.