MONDO_0005923 (Pneumocystis infectious disease) is infections with species in the genus pneumocystis, a fungus causing interstitial plasma cell pneumonia (pneumonia, pneumocystis) and other infections in humans and other mammals. Immunocompromised patients, especially those with aids, are particularly susceptible to these infections. Extrapulmonary sites are rare but seen occasionally. Also known as: Pneumocystis infection.