Patients with immune-mediated inflammatory diseases such as myasthenia gravis (MG) who are on immunosuppressants have reduced long-term humoral immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, a new study by Dutch researchers found.

This reduced response could mainly be attributed to treatment with anti-CD20 and anti-tumor necrosis factor (TNF) agents, according to the researchers. 

Patients also had increased disease activity following infection, but this was mostly mild. 

To investigate the long-term humoral immune responses against SARS-CoV-2 of patients with immune-mediated inflammatory diseases who were on immunosuppressant therapy and whether disease activity increased following infection in unvaccinated patients, the team led by Filip Eftimov, MD, analyzed 193 patients with immune-mediated inflammatory diseases who were being treated with immunosuppressants and 113 patients who were not on immunosuppressants or healthy volunteers (the control group).

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All participants had a confirmed SARS-CoV-2 infection prior to their first vaccination.

The researchers reported that 78% of patients who were treated with immunosuppressants and all of the controls were seropositive for SARS-CoV-2. The rate of seropositivity was lowest in patients being treated with anti-CD20 antibodies and anti-TNF agents compared to other immunosuppressants. 

Increased disease activity following the infection occurred in 26.2% of patients. This led to an increase in the immunosuppressant dose in 8.8% of them.

Self-reported increased disease activity was most frequent among patients with spondyloarthritis and MG. The researchers speculated that as the infection could have triggered exacerbations—a well-known trigger in MG but not spondyloarthritis—the reason for the high proportion of patients reporting increased disease activity could also be that symptoms of COVID-19 may mimic those of immune-mediated inflammatory diseases.

The study is published in BMC Infectious Diseases.


van Dam KPJ, Volkers AG, Wieske L, et al; T2B! Immunity against SARS-CoV-2 study group. Primary SARS-CoV-2 infection in patients with immune-mediated inflammatory diseases: long-term humoral immune responses and effects on disease activity. BMC Infect Dis. 2023;23(1):332. doi:10.1186/s12879-023-08298-6