Exogenous lipoid pneumonia is a rare inflammatory reaction resulting from chronic aspiration of oil or fat. It is most commonly associated with the use of oral mineral oil, and nose drops that contain paraffin. It has also been reported to occur following injection of oils. Computed tomography may demonstrate a mass with decreased attenuation. The diagnosis is confirmed by obtaining sputum or bronchial washings containing lipid-laden alveolar macrophages.
Treatment includes the immediate cessation of the oil product.
3 Of the remaining multiple choice answers, the smooth border and solitary nature of this lesion are more suggestive of a primary lung tumor than of metastatic carcinoma. However, both the chronicity and the bronchoscopic findings effectively eliminate these diagnoses. A lesion associated with postprimary or reactivation tuberculosis is most often seen in the apical lobes. Lung abscess typically causes a cavitary lesion with an air-fluid level. The absence of either a fever or a productive cough makes this diagnosis unlikely.