Final answer:
Pneumocystis pneumonia (PCP) is a fungal infection caused by Pneumocystis jirovecii, primarily affecting immunocompromised individuals. This type of pneumonia is particularly common in patients with AIDS. The diagnosis of PCP can be challenging, but treatment with antimicrobial drugs like trimethoprim-sulfamethoxazole is effective.
Step-by-step explanation:
Pneumocystis pneumonia (PCP) is a type of pneumonia caused by Pneumocystis jirovecii, which was formerly known as Pneumocystis carinii. PCP is a fungal infection that primarily affects immunocompromised individuals, such as those with acquired immunodeficiency syndrome (AIDS). The fungus is transmitted from person to person and resides in the lung tissue, causing respiratory symptoms like fever, cough, and shortness of breath. The diagnosis of PCP can be difficult, but microscopic examination or PCR-based tests can identify the fungus. The most effective treatment for PCP is the combination drug trimethoprim-sulfamethoxazole (TMP/SMZ), although alternative drugs like atovaquone or pentamidine can also be used. Without treatment, PCP can be fatal, particularly in HIV-related cases.