Antirheumatic drugs, B cell depletion and critical COVID-19: correspondence on 'Clinical course of coronavirus disease 2019 (COVID-19) in a series of 17 patients with systemic lupus erythematosus under long-term treatment with hydroxychloroquine' by Mathian et al .

In a recent case series, Mathian et al reported on 17 patients suffering from systemic lupus erythematosus and COVID-19.1 All of these patients received long-term hydroxychloroquine treatment and initial signs and symptoms of COVID-19 were similar to those previously described. However, as 50% of the patients remained hospitalised at the time of publication, the authors cannot comment on the duration and eventual outcome of COVID-19 in all of their patients. Furthermore, it is emerging that hydroxychloroquine does not alter COVID-19.2–4 As such, we actually believe that other immunosuppressive, antirheumatic medications require more attention. Mathian et al rightfully pointed out that besides long-term hydroxychloroquine treatment, steroids and other baseline immunosuppressant drugs are often present in patients with rheumatic diseases. In this context, we found an altered immune response and noticeable prolongation of COVID-19 from the onset of symptoms to intensive care unit (ICU) admission in two patients pretreated with rituximab (RTX) (table 1). View this table: Table 1 Clinical course Patient A (aged 40–60 years) suffered from rheumatoid arthritis, treated with daily doses of leflunomide and low-dose prednisolone. RTX was administered every 6 months. The patient was admitted to ICU 33 days after the onset of COVID-19 symptoms with severe acute …