Pneumocystis pneumonia is caused by Pneumocystis jirovecii, a fungus that is commonly found in the soil. Pneumocystis jirovecii used to be called Pneumocystis carinii, but the taxonomy was changed. The new taxonomy differentiates between Pneumocystis carinii, the organism that infects rodents and Pneumocystis jirovecii, the organism that infects humans. The abbreviation for Pneumocystis pneumonia remains the same: PCP. Symptoms of PCP mimic those of an upper respiratory infection initially.
Progressive Dyspnea
PCP frequently occurs in patients who are unaware of their HIV status and is an AIDS indicator disease in 43 percent of patients. PCP also occurs in patients with CD4 counts less than 100 and in those who are not receiving chronic care for their HIV disease. According to the “5-Minute Clinical Consult” textbook, 40 percent of patients with PCP will have a recurrence without further preventive medications. Symptoms typically begin with a nagging shortness of breath.
Patients note that they are having increasing difficulty performing activities of daily living. Initially, the shortness of breath occurs only with exertion, but will become progressive over time. Hypoxia, or being without adequate oxygen in the body, can range from mild to severe. Hypoxia can affect memory and cause confusion and/or delirium. If hypoxia is severe, the patient may need intubation for a period of time.
Cough
The cough associated with Pneumocystis pneumonia is a dry, nonproductive cough. The cough may be induced by exertion early in the disease. Tachypnea, or rapid breathing, can follow coughing and continue as the disease progresses. Coughing can become severe and violent enough to cause a pneumothorax, or a collapsing of the lung, and may require a chest tube. Chest discomfort occurs and worsens within days to weeks of the infection.
Thrush
According to the Morbidity and Mortality Weekly Report, published in April 2009, oral thrush is a common co-infection of PCP. Candida is a fungus that causes thrush. Symptoms of thrush are the development of creamy white lesions that look like cottage cheese on the mucosal surfaces of the mouth. Candida spreads quickly in patients who are immunocompromised. Thrush can grow not only in the mouth but also extend down the esophagus, causing painful swallowing.
References
- Morbidity and Mortality Weekly Report; Guidelines for Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents; April 2009
- “5-Minute Clinical Consult 2010”; Frank J. Domino, Editor; 2009
