Squalene Aspiration Pneumonia: Thin-Section CT and Histopathologic Findings

Lee, Jin Seong; Gong, Gyungyub; Lim, Tae Hwan

Abstract

PURPOSE: The purpose of this study was to describe the thin-section computed tomography (CT) findings andhistopathologic findings of squalene aspiration pneumonia.
MATERIALS AND METHODS
Thin-section CT scans wereobtained from nine patients with proven exogenous lipoid pneumonia resulting from aspiration of squalene (derivedfrom shark liver oil). The condition was diagnosed by biopsy (n=3), bronchoalveolar lavage (n=4), or sputumcytology and clinical history (n=2); a clinical history of squalene use was confirmed in all patients. Specimensof transbronchial lung biopsy were also reviewed and compared with thin-section CT findings.
RESULTS
Thin-section CT findings included ground-glass attenuation (n=8), consolidations obliterating vascular marking(n=4), scattered centrilobular ground-glass attenuation (n=2), and interlobular interstitial thickening (n=6).Geographic lobular distribution with peripheral spared lobules was observed in all patients. These diseasesinvolved multiple lobes (n=5) and abnormalities were usually located in the dependent portion of the lung. Inthree cases, histopathological correlation showed that ground-glass attenuation reflected intra-alveolarinfiltration of lipid-laden macrophages with exudative fluid. Interlobular septal thickening representedhyperplasia of type II pneumonocytes with mild fibrosis.
CONCLUSION
On the basis of these results, we concludedthat squalene aspiration pneumonia can be reliably diagnosed by thin-section CT findings particularly when theappropriate history is known.