Medical Central Resource
Pneumocystis Carinii Pneumonia
Ruhnke, Thomas J., Jr., MD
11/25/96
Presentation
42 year old female with a remote history of a renal transplant. She presented with a rapid onset of severe shortness of breath.
Imaging Technique
Plain X-ray
Imaging Findings
- Diffuse air-space disease bilateraly
- No pleural effusions
- Stable cardiomegaly
- Oval lucency in peripheral left upper lung
Diagnosis
Pneumocystis Carinii Pneumonia
Discussion
Pneumoncystis Carinii
Pneumoncystis Carinii pneumonia is an opportunistic infection caused by an inhaled protozoa. However this classification remains controversial as the organism has some features in common with the fungi. Patients often demonstrate simultaneous infections with other opportunistic pathogens including cytomegalo virus, Mycobacterium avium intracellulare and Herpes simplex virus. Pneumocystis carinii affects a wide range of immunocompromised hosts including patients with AIDS, organ transplants, leukemia/lymphoma, congenital immunodeficiencies and long-term steroid use. It is the most common cause of an interstitial pneumonia presenting in an immunocompromised host.
Patients with AIDS usually have an insidious onset over several weeks, whereas other immunocompromised patients typically have a rapid onset. Symptoms are severe and include dsypnea, cyanosis and an increased A-a oxygen gradient.
Diagnosis is most commonly made with bronchoalveolar lavage although direct immunofluorescent antibodies are an alternative.
Treatment and prophylaxis are typically with Bactrim.
Radiographic presentation consists of a perihilar and basilar predominant reticular pattern which may be very subtle at the time of initial presentation. As the disease progresses ground glass opacities develop and eventually air-space disease which may become diffuse and coalescent. Other common findings include atelectasis, hyperaeration and pneumothorax. Pleural effusions and adenopathy are uncommon. Predominantly upper lobe involvement was previously seen in patients receiving prophylaxis with aerosolized pentamidine but as this practice wanes in popularity this pattern is becoming less common. Patients may also develop thin-walled cysts and bullae. When wide-spread dissemination of the organism has occurred calcified lymph nodes may be seen throughout the body.
Submitted by: Thomas J. Ruhnke,Jr.,Maj,USAF,MC,Wilford Hall Medical Center
Reviewed by: Michael W. Freckleton,Maj,USAF,MC,Wilford Hall Medical Center
