대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Cytomegalovirus (CMV) Pneumonia

Radiologic Findings

HRCT scans show multifocal, patchy areas of ground-glass attenuation in both lungs.
Multiple small nodules are also noted.

Brief Review

CMV infection is the most common viral infection in immunosuppressed patients such as organ transplantation patients (up to 90%) or AIDS patients (up to 80%).
In organ transplantation patients, CMV pneumonia causes fever, pulmonary infiltrates and hypoxia resulting in the adult respiratory distress syndrome.
It typically occurs more than 2 months (2 weeks - 4, 5 months) following transplantation.
CMV pneumonia is more often recognized in late-stage disease (CD4+ < 50/mm3) and should be included in the differential diagnosis of diffuse ground-glass opacification and/or consolidation, especially in AIDS patients unresponsive to therapy for PCP (Pneumocystis carinii pneumoniae).
CMV is frequently detected by cytology, histopathology or by culture.
Lung biopsy may be necessary to establish the diagnosis.
Histologically, the lung reveals a diffuse mononuclear interstitial pneumonia accompanied by considerable edema in the alveolar walls that may even spill into the alveolar spaces.
In addition, the alveolar cells have characteristic intranuclear and intracytoplasmic inclusions.
Like other viral infection, it has a broad spectrum of radiologic presentation (normal to suggestive of bronchopneumonia), which is frequently fatal.
The radiologic opacities are the result of cellular infiltrates in the interstitium, as well as intra-alveolar hemorrhage and edema.
HRCT findings are patchy bilateral foci of ground-glass opacification and/or consolidation (90%), scattered, poorly defined nodules and/or masses (69%), reticulation (intralobular/interlobular interstitial thickening) and diffuse small nodules.
Nodules have been reported involving the outer one-third of the lungs.
In early stages, unilateral, focal and even nodular infiltrates have been seen.

References

1. McGuinness G, Scholes JV, Garay SM, Leitman BS, McCauley DI, Naidich DP. Cytomegalovirus pneumonitis: spectrum of parenchymal CT findings with pathologic correlation in 21 AIDS patients. Radiology 1994;192:451-459

2. Leung AN, Gosselin MV, Napper CH, Braun SG, Hu WW, Wong RM, Gasman J. Pulmonary infections after bone marrow transplantation: clinical and radiographic findings. Radiology 1999;210:699-710

3. Kang EY, Patz EF, Muller NL. Cytomegalovirus pneumonia in transplant patients: CT findings. J Comput Assist Tomogr 1996;20:295-299

3. Moon JH, Kim EA, Lee KS, Kim TS, Jung K-J, Song J-H. Cytomegalovirus pneumonia: high-resolution CT findings in ten non-AIDS immunocompromised patients. Korean J Radiol 2000; 1:73-78

Keywords

Lung, Infection, Viral infection,