A complex COVID-19 case with rheumatoid arthritis treated with tocilizumab.

Recurrences of COVID-19 were observed in a patient with long-term usage of hydroxychloroquine, leflunomide, and glucocorticoids due to her 30-year history of rheumatoid arthritis (RA). Tocilizumab was applied and intended to target both COVID-19 and RA. However, disease of this patient aggravated after usage of tocilizumab. After the discussion of a multiple disciplinary team (MDT) including rheumatologists, antimicrobial treatments were applied to target the potential opportunistic infections (Pneumocystis jirovecii and Aspergillus fumigatus), which were authenticated several days later via high throughput sequencing. As an important cytokine in immune responses, IL-6 can be a double-edged sword: interference in the IL-6-IL-6 receptor signaling may save patients from cytokine release storm (CRS), but can also weaken the anti-infectious immunity, particularly in rheumatic patients, who may have received a long-term treatment with immunosuppressive/modulatory agents. Thus, we suggest careful considerations before and close monitoring in the administration of tocilizumab in rheumatic patients with COVID-19. Besides tocilizumab, several disease-modifying antirheumatic drugs (DMARDs) can also be applied in the treatment of COVID-19. Therefore, we also reviewed and discussed the application of these DMARDs in COVID-19 condition.