A case of new-onset rheumatoid vasculitis becoming evident in the course of treatment for Pneumocystis jirovecii pneumonia.

When patients with autoimmune diseases, such as rheumatoid arthritis (RA), are treated with potent immunosuppressive therapy, the risk of opportunistic diseases inevitably increases. If patients have the misfortune to suffer from both opportunistic and active autoimmune diseases, correct diagnosis could sometimes be difficult since both diseases have inflammatory nature. The choice of treatment is another challenge in that aggressive immunosuppressive therapy can fuel the opportunistic infection. Here we report a case of RA patient with new onset rheumatoid vasculitis that was diagnosed in the process of treatment of Pneumocystis jirovecii pneumonia.