During the last decades, the number of Pneumocystis jirovecii pneumonia (PJP) has grown in HIV-negative patients due to the increasing use of organ transplantation, immunosuppressive drugs and targeted therapies [1]. Guidelines about PJP prophylaxis in immunocompromised (IC) HIV-negative patients are scarce. CD4+ cell count is less helpful in IC patients than in HIV-positive, and B cells may help clearing Pneumocystis infection [2]. Rituximab is a chimeric monoclonal antibody that targets human cell-surface glycoprotein CD20 expressed on B cells.
