Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Acute eosinophilic pneumonia
- Radiologic Findings
- He had a history of recent work in heavy smoking environment for 3 weeks. For the diagnostic work up, BAL was done. On BAL analysis, the count of eosinophils was 42%.
Chest PA shows diffuse bilateral ill-defined opacities.
Lung setting of the chest CT images show ill-defined ground-glass opacities and consolidation in peribronchial and peripheral portion of both lungs, and smooth interlobular septal and peribronchial interstitial thickening in both lungs.
Mediastinal setting of chest CT image shows small amount of bilateral pleural effusion.
- Brief Review
- Acute eosinophilic pneumonia (AEP) represents a clinical entity that is distinct from other idiopathic eosinophilic lung diseases. Diagnostic criteria include acute severe febrile illness of less than 5 days of duration; hypoxemia; diffuse alveolar or mixed alveolar-interstitial opacities on chest radiographs; BAL fluid consisting of more than 25% eosinophils; absence of parasitic, fungal, or other infection; prompt and complete response to corticosteroids; and no relapse after discontinuation of corticosteroids. Peripheral blood eosinophils percentages are usually normal, although they become elevated during the subsequent clinical course. Unlike with blood eosinophils, a very high percentage of BAL eosinophils is characteristic of AEP. The majority of cases are idiopathic. Occasionally, it may result from drug reaction or inhalation exposure to smoke, particularly cigarette smoke. Tobacco smoke has been shown to be a trigger for acute eosinophilic pneumonia, especially in new-onset smokers. Patients respond rapidly to high doses of corticosteroids, usually within 24 hrs.
Typical radiographic finding is diffuse bilateral reticular opacities with or without patchy consolidation and pleural effusion. On chest CT, it shows findings of bilateral patchy area of ground glass opacity and consolidation accompanied with poorly defined nodules and smooth interlobular septal thickening. Pleural effusion is commonly combined.
The radiologic differential diagnosis for AEP includes hydrostatic pulmonary edema, adult respiratory distress syndrome or acute interstitial pneumonia, and atypical bacterial or viral pneumonia. However, developing a clinicoradiologic differential diagnosis for AEP is often difficult because initial peripheral blood eosinophil counts are usually normal.
- References
- 1. Daimon T, Johkoh T, Sumikawa H, et al. Acute eosinophilic pneumonia: Thin-section CT findings in 29 patients. Eur J Radiol. 2008:65(3);462-467.
2. Jeong YJ, Kim KI, Seo IJ, et al. Eosinophilic lung diseases: a clinical, radiologic and pathologic overview. Radiographics. 2007:27(3);617-637.
- Keywords
- lung, eosinophilic,