Pneumocystis jirovecii Pneumonia

The life cycle of Pneumocystis jirovecii is complicated. It tries to find a damaged immune system to replicate, leading to life-threatening complications. With the treatment of immunosuppressive drugs, Pneumocystis jirovecii pneumonia has become a common opportunistic infection in non-AIDS populations. A CD4+ lymphocyte count of <200 cells/μL is a major risk factor for Pneumocystis jirovecii pneumonia.