Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:
-- The first section of this topic is shown below --
- Originally called Pneumocystis carinii pneumonia, then renamed Pneumocystis jirovecii but still referred to as PCP
- Most common opportunistic infection in patients with HIV, even with PCP prophylaxis and antiretroviral therapy
- Believed to be transmitted by respiratory-aerosol route:
- Cysts colonize respiratory tract.
- Cysts rupture and multiple trophozoites release and form foamy exudate in alveoli.
- Most cases are believed to represent reactivation of latent disease, although person-to-person transmission suggested.
- Actual mode of transmission is unclear.
- Pneumocystis is classified as a fungus.
- Pneumocystis occurs in hosts with altered cellular immunity:
- HIV infection (most common, especially when CD4 count <200 cells/mm3)
- Corticosteroid treatment
- Organ transplantation
PCP in children is typically more severe.