Pneumocystis pneumonia

Pneumocystis pneumonia
Other namesPneumocystis pneumonia; Pneumocystis jirovecii pneumonia; Pneumocystis jiroveci pneumonia; Pneumocystis carinii pneumonia [outdated term]; pneumocystosis; pneumocystiasis; interstitial plasma cell pneumonia; plasma cell pneumonia
Pneumocystis jirovecii cysts from bronchoalveolar lavage, stained with Toluidine blue O stain
SpecialtyInfectious disease, Pulmonology
CausesPneumocystis jirovecii
Risk factorsWeakened immune system
Differential diagnosisOther types of pneumonia
Medicationco-trimoxazole, steroids, pentamidine, trimetrexate, dapsone, atovaquone, primaquine, pafuramidine maleate and clindamycin.

Pneumocystis pneumonia (PCP), also known as Pneumocystis jirovecii pneumonia (PJP), is a form of pneumonia that is caused by the yeast-like fungus Pneumocystis jirovecii.

Pneumocystis specimens are commonly found in the lungs of healthy people although it is usually not a cause for disease. However, they are a source of opportunistic infection and can cause lung infections in people with a weak immune system or other predisposing health conditions. PCP is seen in people with HIV/AIDS (who account for 30-40% of PCP cases), those using medications that suppress the immune system, and people with cancer, autoimmune or inflammatory conditions, and chronic lung disease.