AUTHOR AND EDITOR INFORMATION

Section 1 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

INTRODUCTION

Section 2 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Background

Pneumocystis carinii pneumonia (PCP) is caused by the ubiquitous unicellular eukaryote, P carinii. This organism is a rare cause of infection in the general population, but it is a frequent cause of morbidity and mortality in persons who are immunocompromised, especially patients with acquired immunodeficiency syndrome (AIDS).^{1, 2, 3, 4}

Patients who do not have AIDS but are immunocompromised and at risk for PCP include individuals with hematologic malignancies⁴; organ transplant recipients^{5, 6}; and those receiving long-term steroid or cytotoxic therapy, including patients with systemic vasculitis or other autoimmune deficiency. Other patients with immune deficiency disorders who are at particular risk for PCP include those with thymic dysplasia, those with severe combined immunodeficiency, and those with hypogammaglobulinemia. Severe malnutrition may predispose patients to PCP.

For excellent patient education resources, visit eMedicine's Lung and Airway Center, Pneumonia Center, Immune System Center, and Sexually Transmitted Diseases Center. Also, see eMedicine's patient education articles Viral Pneumonia, Acute Respiratory Distress Syndrome, HIV/AIDS, and HIV Testing.

Related eMedicine topics:
Acute Respiratory Distress Syndrome
Infections in the Immunocompromised Host
Pneumonia, Immunocompromised

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Resource Center HIV Transmission & Prevention
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Specialty Site Diabetes & Endocrinology
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CME Controversies in HIV Management (Slides With Transcript)
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CME/CE IAS 2007: Management of Pediatric HIV Infection, and Prevention of Mother-to-Child HIV Transmission

Pathophysiology

P carinii has a controversial taxonomy. However, on the basis of findings from ultrastructural and molecular analysis of its mitochondrial DNA and its affinity for fungal staining, the organism is currently recognized as a fungus. P carinii organisms consist of small cysts, each of which produces as many as 8 intracystic sporozoites. Upon maturity, the cysts rupture and release the sporozoites, which in turn differentiate into trophozoites. The trophozoites subsequently develop into cysts and repeat the cycle. The mode of transmission is believed to be via the inhalation of air-borne cysts.

Almost all children acquire antibodies to P carinii by the age of 2 years. Disease develops only in individuals who are immunocompromised, probably as a result of reactivation of a latent infection. Trophozoites attach to the cell membrane of type 1 alveolar pneumocytes, with subsequent cell death and leakage of proteinaceous fluid into the alveolar spaces. Histologically, the alveolar spaces are filled with an amphophilic, foamy, amorphous material composed of the parasites and cell debris; this material resembles proteinaceous edema fluid. Trophozoites are visible on electron microscopy and on smears or sections stained with toluidine blue or polychrome, but they are not visible by using routine histologic techniques.

No reliable antigen detection methods are available yet. The organism cannot be grown in culture; therefore, the diagnosis of PCP relies on morphologic identification of the organism. The standard method of diagnosis is via cytologic examination of induced sputum specimens or bronchoalveolar lavage (BAL) washings. BAL has a sensitivity of as high as 90% and a specificity of 82%. In a minority of patients, transbronchial, percutaneous, or open lung biopsy may be necessary. Alternatively, patients who present with typical clinical and radiographic manifestations may be treated empirically, with invasive procedures reserved for patients who have atypical presentations or in whom empiric therapy fails to elicit a satisfactory response.

Related eMedicine topics:
Infections in the Immunocompromised Host
Pneumonia, Fungal
Pneumonia, Immunocompromised
Transthoracic Needle Biopsy

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Frequency

United States

Pneumocystis carinii pneumonia (PCP) was exceptionally rare before the advent of the AIDS epidemic, with a reported incidence of 0.3 cases per 1,000,000 persons per year. The AIDS epidemic led to an initial dramatic increase in the incidence of PCP, although this subsequently declined significantly following the introduction of trimethoprim-sulfamethoxazole (TMP-SMZ) PCP prophylaxis. PCP is no longer the most common pulmonary complication or infection in patients with AIDS, having been supplanted by bacterial infection. However, PCP remains the most common pulmonary opportunistic infection, and it still affects 60% of patients during the course of the illness.

PCP remains a common AIDS-defining illness, although its incidence as an index disease has declined. The reduction is due partly to a true reduction in incidence, attributed mainly to the widespread use of effective PCP prophylaxis, and partly to a broadening of the diagnostic criteria for AIDS. PCP accounts for approximately 40% of index diagnoses, as compared with approximately 60% at the start of the AIDS epidemic.

Effective PCP prophylaxis not only reduces the incidence of PCP but also lengthens disease-free intervals between episodes.

In patients without AIDS who are immunocompromised, the incidence of PCP before the administration of prophylactic therapy is 10-20%; with prophylactic therapy, it decreases to 0-10%.

Related Medscape topics:
Resource Center Antiretroviral Drug Resistance and Testing
Resource Center Antiretroviral Therapy

International

In the African population, the incidence of Pneumocystis carinii pneumonia (PCP) in patients with AIDS is lower than that of other groups, and only 9% of patients are affected.

Mortality/Morbidity

Although Pneumocystis carinii pneumonia (PCP) is less common than bacterial respiratory tract infection in patients with AIDS, this condition accounts for more deaths. Initially, 50% of deaths due to respiratory failure in patients with AIDS were attributed to P carinii; the organism was identified in two thirds of cases. However, with a declining incidence of PCP, wider recognition, and more effective treatment, the mortality rate has decreased to approximately 5% overall.

• Slowly progressive forms, atypical features, and complications such as pneumothorax are associated with significantly higher mortality rates. Mortality rates increase to 75-100% in patients whose condition fails to respond to therapy during the first 5-10 days.
• The mortality rate in patients without AIDS but who are immunocompromised is 40%.

Race

Pneumocystis carinii pneumonia (PCP) is 3 times more common in white patients than black patients, despite a higher use of prophylactic therapy in the white population.

Sex

Rates of infection of Pneumocystis carinii pneumonia (PCP) in homosexual and bisexual males are more than twice that of those in females.

Age

Individuals of any age can be affected with Pneumocystis carinii pneumonia (PCP), particularly when their immune system is compromised.

Clinical Details

Pneumocystis carinii pneumonia (PCP) can occur at any level of immune compromise, but this disease is more common in patients who are not receiving PCP prophylaxis and who have CD4 levels less than 200 cells per cubic millimeter (cells/mm³). PCP is most common in persons with profound levels of immunodeficiency, that is, in those with CD4 levels less than 100 cells/mm³.

PCP usually appears with an insidious onset of malaise, weight loss, and low-grade fever (79-100%) that is associated with a dry cough (59-91%). However, the symptoms may be more severe, and dyspnea (29-95%), cyanosis, and respiratory failure (5-30%) may be present. Immunocompromised patients without AIDS but with PCP tend to present more acutely and have more fulminant disease. Chest pain (14-23%) and productive cough (23-30%) are reported. Patients classically demonstrate marked desaturation with exercise. An elevated serum lactate dehydrogenase level is sensitive for PCP, but this finding is nonspecific and has limited diagnostic value.

Complications of PCP include spontaneous pneumothorax and hypoxemia secondary to an adult respiratory distress–like syndrome. Intubation may be needed, and this complication has a significantly worse prognosis.

Extrapulmonary disease occurs in 1% of patients due to hematogenous spread of the organism. In particular, this is associated with nebulized pentamidine, which was once used as a prophylactic agent; however, this therapy has been superseded by oral antibiotics. With nebulized drug administration, less than 10% of the dose enters the systemic circulation, potentially allowing the organism to cause systemic disease or lie dormant in extrapulmonary sites, acting as a source of recurrent infection. The bone marrow, spleen, liver, lymph nodes, small bowel, and eyes can be affected. Less commonly involved areas include the adrenal glands, kidneys, pituitary gland, skin, thyroid gland, and gastrointestinal tract.

A subset of patients presents with atypical clinical and radiographic features termed chronic PCP. These patients have a prolonged clinical course over months or years, with persistent stable symptoms and radiographic abnormalities corresponding to pathologic findings of interstitial fibrosis, traction bronchiectasis, and honeycombing.

Preferred Examination

Chest radiographs should be included in the initial evaluation for Pneumocystis carinii pneumonia (PCP). Frequently, these are the only images required. High-resolution computed tomography (HRCT) scanning^{7, 8, 9, 10, 11} and, occasionally, gallium-67 (⁶⁷Ga) scanning^{12, 13, 14, 15} are useful in symptomatic patients in whom chest x-ray findings are normal or equivocal.

Limitations of Techniques

Chest radiographic findings may be normal in 10-39% of patients with Pneumocystis carinii pneumonia (PCP). With both CT and ⁶⁷Ga scanning, the appearance of PCP is nonspecific.

DIFFERENTIALS

Section 3 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Other Problems to Be Considered

AIDS-related lymphoma
Kaposi sarcoma
Other opportunistic infections
Pulmonary edema
Pulmonary hemorrhage

RADIOGRAPH

Section 4 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Findings

• In patients with Pneumocystis carinii pneumonia (PCP), chest radiographs classically demonstrate bilateral, diffuse, often perihilar, fine, reticular interstitial opacification, which may appear somewhat granular. This opacification progresses to air-space consolidation over 3-4 days. This appearance may be followed by coarse reticulation as the infection resolves.^{7, 8, 14}
• Chest x-ray findings may be normal in 10-39% of patients, or radiographic changes may lag behind the clinical symptoms.
• Trends are changing in the radiographic manifestations of PCP; features that previously were considered unusual are seen with increasing frequency.⁷
• Atypical radiographic patterns are reported to occur in 5% of patients and include cystic lung disease, spontaneous pneumothorax, and isolated lobar or focal consolidation, particularly with an upper-lobe predominance.
• Pulmonary nodules, which may be cavitated, have been described but they are rare in PCP. Pulmonary nodules have been shown histologically to represent granulomas, and these are usually encountered early in the course of HIV infection when the patient is still capable of mounting a granulomatous response.
• Miliary nodularity, bronchiectasis, endobronchial lesions, and mediastinal lymphadenopathy (18%), which may show calcification, have been reported.¹⁶
• Pleural effusions and hilar lymphadenopathy are uncommon. Indeed, the presence of an effusion should prompt the search for a different pathogen.
• Cysts are visible on chest radiographs in 10% of patients, although these entities are appreciated far more commonly on HRCT scans (33%). Findings of cysts or pneumatoceles are not infrequent in patients with PCP.
• Cysts may occur in the acute or postinfective period and range in number, size, shape, and distribution.
• Cysts are commonly multiple, with a predilection for the upper lobes, and may be related to an ongoing or previous PCP infection.
• The etiology of the cysts is unclear, but several hypotheses have been proposed, including the release of elastase from alveolar macrophages, which causes tissue necrosis and cavitation; vascular invasion with subsequent infarction; and cavitation obstruction of small airways, leading to a ball-valve effect.
• Radiologic-pathologic correlation has shown persistent infection in some of the cyst walls.
• Spontaneous pneumothorax may be a feature of PCP infection, with a reported incidence of approximately 6%, rising to approximately 35% in patients with cysts. Development of a spontaneous pneumothorax has important implications for treatment and prognosis of patients because this condition tends to be refractory to conventional tube drainage, frequently requiring pleurodesis or surgical intervention. In addition, spontaneous pneumothorax is associated with a significantly higher mortality rate, particularly in patients on ventilation. Pneumothoraces are frequently bilateral.
• Chest radiographic findings usually resolve within 2-4 weeks with successful treatment. This resolution may be accelerated by the use of steroids. Occasionally, radiographic findings remain abnormal, and the images demonstrate reticular opacities, interstitial fibrosis, or focal scarring and/or nodularity.

Related eMedicine topic:
Tube Thoracostomy

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Specialty Site Infectious Diseases
Specialty Site Pathology & Lab Medicine
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Specialty Site Radiology

Degree of Confidence

Despite the presence of overlapping radiographic features in Pneumocystis carinii pneumonia (PCP), chest x-ray findings are often of diagnostic value. Usually, chest radiography is the only imaging required, and the overall accuracy for the diagnosis of PCP is approximately 75%.

False Positives/Negatives

Chest x-ray findings may be normal in 5-30% of patients with Pneumocystis carinii pneumonia (PCP). The literature reports a false-negative rate for the diagnosis of PCP by using chest radiography of 35-40%. Adult respiratory distress syndrome, pulmonary edema, other opportunistic lung infections, lymphoma, and Kaposi sarcoma may mimic PCP.

CT SCAN

Section 5 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Findings

HRCT scanning is more sensitive than chest radiography for the detection and exclusion of Pneumocystis carinii pneumonia (PCP), and HRCT scan results may be positive when chest x-ray findings are normal.^{7, 8, 9, 10, 11}

• The hallmark finding of PCP on HRCT scans is ground-glass attenuation, which is present in more than 90% of patients and represents an exudative alveolitis. The term ground-glass refers to parenchymal opacification, which does not obscure the underlying pulmonary architecture. This usually occurs in a bilateral, symmetric, predominantly perihilar distribution and may be geographic or mosaic in appearance (56%), with areas of normal lung adjacent to areas of affected lung.
• Thickening of interlobular septa (due to edema) and foci of consolidation may be associated. Septal thickening in the subacute stage is usually more extensive and represents organizing inflammatory infiltrate.

Degree of Confidence

In the proper clinical setting, the presence of ground-glass attenuation on HRCT scans in patients with AIDS is virtually diagnostic of Pneumocystis carinii pneumonia (PCP), with a diagnostic accuracy of approximately 94%. Normal HRCT findings virtually exclude the possibility of PCP.

False Positives/Negatives

Although ground-glass attenuation is highly suggestive of Pneumocystis carinii pneumonia (PCP), cytomegalovirus (CMV) pneumonitis and lymphoid interstitial pneumonia can rarely give rise to a similar appearance. However, CMV pneumonitis is rare in patients with CD4 counts of greater than 50 cells/mm³. Although PCP can give rise to parenchymal nodules, this feature is more common in CMV infection; thus, the combination of ground-glass attenuation and nodularity is more likely to be secondary to CMV infection.

Motion artifacts and low lung volumes due to reduced inspiratory effort may occasionally give rise to a spurious ground-glass appearance.

Ground-glass opacification can be seen in many other conditions, including pulmonary edema, pulmonary hemorrhage, drug toxicity, other infections, and hypersensitivity pneumonitis. Clinical correlation usually allows the exclusion of most of these differential diagnoses (see also Differentials and Other Problems to Be Considered).

Hilar lymphadenopathy may occur in patients with tuberculosis, Mycobacterium avium-intracellulare (MAI or MAC) infection, fungal infection, Kaposi sarcoma, and AIDS-related lymphoma, but this condition is rare in patients with PCP.

ULTRASOUND

Section 6 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Findings

Ultrasonography may be useful in the evaluation of systemic P carinii infection (hepatic/splenic and renal microabscesses), but this imaging modality is of no value in assessing pulmonary disease.

NUCLEAR MEDICINE

Section 7 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Findings

• ⁶⁷Ga citrate is useful in the investigation of fevers of unknown origin (FUO) because it is taken up by areas of inflammation, infection, and tumor. ⁶⁷Ga also accumulates in Pneumocystis carinii pneumonia (PCP) infection and can detect PCP in asymptomatic patients with AIDS in the absence of abnormal plain radiographic findings.

  The most common pattern of radionuclide uptake seen in patients with PCP is diffuse pulmonary uptake.^{12, 13, 14, 15} A negative heart with diffuse pulmonary uptake in a patient with AIDS is indicative of PCP. However, uptake varies in patients treated with aerosolized pentamidine and is observed only in areas of the lungs where the drug fails to reach. Patchier uptake is seen with recurrent PCP; however, gallium scanning is expensive, is poorly tolerated by patients, and requires delayed scans at 48 hours. In practice, this study is little used.

• Indium 111 (111In)–labeled autologous leukocytes accumulate in PCP, but the overall performance in immunosuppressed patients is poor compared with ⁶⁷Ga studies.
• The clearance of technetium-99m (^99mTc) diethylenetriamine pentaacetic acid (DTPA) aerosol across the alveolar-capillary membrane is accelerated in patients with PCP. The shortened half-life for clearance of radionuclide activity has been shown to be more sensitive than in ⁶⁷Ga imaging. After effective therapy, the shortened clearance times rapidly return to normal.¹⁷
• ^99mTc-labeled nonspecific polyclonal human immunoglobulin (HIG) has been used in the evaluation of patients with AIDS.^{13, 18} The sensitivity varies from 0-100% in PCP. Similar to ⁶⁷Ga scanning, ^99mTc-labeled nonspecific polyclonal HIG appears more sensitive than chest radiography. The pattern of activity is usually diffuse, but focal uptake has been described.
• An Fab fragment of an antibody labeled with ^99mTc has been used to image the infection in patients with AIDS; this fragment recognizes PCP. In a small series, a sensitivity of 85.7% and a specificity of 86.7% were achieved.¹⁹

Degree of Confidence

• ⁶⁷Ga scans are extremely sensitive for Pneumocystis carinii pneumonia (PCP), with reported sensitivities of 87-100%; however, the specificity of ⁶⁷Ga imaging may vary considerably and reportedly ranges from 20-100%. This variation partly depends on the nuclear medicine department's clinical practice and referral patterns. The specificity can be increased when diffuse pulmonary uptake of greater intensity than the liver is included in the diagnostic criteria. The discordance between pulmonary ⁶⁷Ga uptake and negative chest radiographic findings in patients with AIDS can be used to increase the specificity in detecting PCP.
• The overall performance with the uptake of radiolabeled leukocytes is poor in PCP, and this technique should be reserved for imaging suggesting bacterial pneumonia and infections at other sites in patients with AIDS and patients who are immunosuppressed but do not have AIDS.
• ^99mTc DTPA aerosol clearance times provide a simple and noninvasive technique for follow-up imaging in patients receiving treatment for PCP. Although abnormalities in the clearance of ^99mTc DTPA aerosol have been reported with other pulmonary infections in patients with AIDS, a clearance time greater than 4.5% per minute has been shown to be specific for PCP in patients with AIDS.
• The sensitivity and specificity of ^99mTc–labeled HIG are too variable to warrant use of this technique in patients with AIDS-related PCP. Further large-scale studies are required to justify its use.

False Positives/Negatives

⁶⁷Ga also accumulates in lymphoma and other malignant processes that are associated with AIDS.

Accelerated clearance of ^99mTc DTPA aerosol is not specific in patients with Pneumocystis carinii pneumonia (PCP), and this process has been reported with other pneumonitides that are associated with AIDS.

ANGIOGRAPHY

Section 8 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Findings

Pulmonary or bronchial angiography has no role in the diagnosis of Pneumocystis carinii pneumonia (PCP).

INTERVENTION

Section 9 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Bronchoalveolar lavage (BAL) is the criterion standard for the diagnosis of Pneumocystis carinii pneumonia (PCP), with a sensitivity of 86% and a specificity of 99-100%. When combined with transbronchial biopsy, the sensitivity increases to 98-100%. Bilateral BAL can increase yield. When high-resolution CT (HRCT) scan findings are nondiagnostic, CT scanning may be of value in directing bronchoscopic lavage or guiding open, transbronchial, or percutaneous needle biopsy of lesions. Needle biopsy is safe and accurate for the diagnosis of focal pulmonary lesions in patients with AIDS. Diagnostic rates of approximately 85% have been reported. Open lung biopsy rarely is required.

Related Medscape topics:
Specialty Site Pathology & Lab Medicine
Specialty Site Pulmonary Medicine
Specialty Site Radiology

Medical/Legal Pitfalls

• Ensuring that PCP is not overlooked in patients who are immunocompromised is important because mortality rates from the disease can be high (see Mortality/Morbidity).
• Recognizing PCP in patients without AIDS but who are immunocompromised is even more important, because the mortality rate in these patients is exceptionally high at 40%.

Related Medscape topics:
Resource Center Antiretroviral Drug Resistance and Testing
Resource Center Antiretroviral Therapy
Resource Center HIV Pathogenesis
Resource Center HIV Transmission & Prevention
Resource Center Medical Malpractice and Legal Issues

Special Concerns

• A diagnosis of PCP in patients who are known not to be immunocompromised may indicate the need for HIV testing.

Related Medscape topic:
Specialty Site HIV/AIDS
Specialty Site Infectious Diseases
Specialty Site Pulmonary Medicine

ACKNOWLEDGMENTS

Section 10 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

The authors and editors of eMedicine gratefully acknowledge the contributions of previous coauthor Dr Hari Panigrahi to the development and writing of this article.

MULTIMEDIA

Section 11 of 12  

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

Media file 1:  This radiograph depicts a diffuse, fine, reticular opacification as a result of Pneumocystis carinii pneumonia.
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Media file 2:  This radiograph depicts the typical bilateral air-space consolidation of Pneumocystis carinii pneumonia in a patient with acquired immunodeficiency virus infection.
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Media file 3:  This chest radiograph shows bilateral upper-lobe pneumatoceles after a Pneumocystis carinii infection in a patient with acquired immunodeficiency syndrome.
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Media type:  X-RAY

Media file 4:  This chest radiograph shows residual interstitial opacities in a patient with a history of Pneumocystis carinii pneumonia.
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Media type:  X-RAY

Media file 5:  High-resolution computed tomography scan obtained through the upper lobes in the prone position in a patient with a history of Pneumocystis carinii pneumonia (same patient as in Image 4). This image shows parenchymal and subpleural cysts and patchy fibrosis that resulted from the Pneumocystis carinii infection.
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Media type:  CT

Media file 6:  Bilateral spontaneous pneumothoraces resulting from Pneumocystis carinii pneumonia in a man with HIV infection that was previously undiagnosed.
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Media file 7:  High-resolution CT (HRCT) scan in a 32-year-old man with HIV infection showing ground-glass appearance due to Pneumocystis carinii pneumonia.
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Media type:  CT

Media file 8:  A posteroanterior chest radiograph from a 33-year old male patient with human immunodeficiency virus and Pneumocystis carinii pneumonia. The pneumonia is seen as lower lobe alveolar infiltrates (see also Image 9).
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Media type:  X-RAY

Media file 9:  An anteroposterior radiograph from a 33-year old male patient with human immunodeficiency virus and Pneumocystis carinii pneumonia (same patient as in Image 8). This image shows features of a right-sided tension pneumothorax.
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Media type:  X-RAY

Media file 10:  A posteroanterior chest radiograph from a patient with human immunodeficiency virus infection. This image shows redistribution of Pneumocystis carinii pneumonia to the upper lobes following aerosolized pentamidine prophylaxis (see also Image 11).
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Media type:  X-RAY

Media file 11:  A magnified view of lung apices from a patient with human immunodeficiency virus infection (same patient as in Image 10). This image shows the redistribution of Pneumocystis carinii pneumonia to the upper lobes following aerosolized pentamidine prophylaxis.
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Media type:  Radiograph

REFERENCES

Section 12 of 12

• Authors and Editors
• Introduction
• Differentials
• Radiograph
• CT Scan
• Ultrasound
• Nuclear Medicine
• Angiography
• Intervention
• Acknowledgments
• Multimedia
• References

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Article Last Updated: Jul 3, 2008