label: Pneumocystis jirovecii pneumonia
label_lc: pneumocystis jirovecii pneumonia
description: "An opportunistic disease caused by invasion of unicellular fungus Pneumocystis jirovecii. Transmission of P. jirovecii cysts takes place through the airborne route, and usually, its presence in lungs is asymptomatic. However, people with impaired immunity, especially those with CD4+ T cell count below 200/microliter, are still at risk of the development of Pneumocystis pneumonia due to P. jirovecii invasion. Symptoms induced by this disease are not specific: progressive dyspnea, non-productive cough, low-grade fever, arterial partial pressure of oxygen below 65 mmHg, and chest radiographs demonstrating bilateral, interstitial shadowing."