What Is Pneumocystis Pneumonia?
Pneumocystis pneumonia, also called PCP, is a serious fungal infection that affects the lungs. It is most common in people whose immune systems are weakened by illness or certain medical treatments.
People at higher risk for PCP include those with:
- HIV/AIDS
- Cancer
- Organ transplants
- Autoimmune diseases requiring immunosuppressive medicines
- Long-term steroid use or other treatments that weaken the immune system
The infection is caused by a fungus called Pneumocystis jirovecii. While many people may be exposed to this fungus without becoming sick, it can lead to severe lung infection in people with reduced immune defenses.
Symptoms
Symptoms of PCP often develop gradually and may become worse over time.
Common symptoms include:
- Fever
- Dry cough
- Shortness of breath
- Trouble breathing during activity
- Chest discomfort
- Fatigue
- Night sweats
- Weight loss
How Is It Diagnosed?
Healthcare providers diagnose PCP using a physical exam, medical history, imaging tests, and laboratory testing.
Tests may include:
- Chest X-ray
- CT scan in some cases
- Blood tests
- Oxygen level testing
- Sputum testing
- Bronchoscopy to collect lung samples
These tests help confirm the infection and evaluate how severely the lungs are affected.
How Is It Treated?
PCP usually requires prescription antibiotics. Severe cases may need treatment in the hospital.
Treatment may include:
- Trimethoprim-sulfamethoxazole (TMP-SMX)
- IV antibiotics for severe infections
- Oxygen therapy if breathing problems are significant
- Corticosteroids in certain severe cases
People with weakened immune systems may also need preventive medicine to reduce the chance of future infections.
With early diagnosis and treatment, many people recover successfully, though close follow-up care is important.
