Amiodarone pulmonary toxicity: CT findings in symptomatic patients

The computed tomographic (CT) chest scans of 11 patients who developed respiratory or constitutional symptoms while receiving amiodarone therapy were reviewed. CT findings indicative of significant amiodarone exposure included (a) high-attenuation parenchymal-pleural lesions in eight of the 11 patients (73%), and (b) increased liver and/or spleen attenuation in 10 of the 11 patients (91%). Nonspecific pulmonary infiltrates were identified in nine of the 11 patients (82%). Four patients had interstitial infiltrates, four had mixed alveolar and interstitial disease, and one had a conglomerate mass. CT findings of high-attenuation parenchymal-pleural abnormalities are thought to be related to the iodinated chemistry of the drug and its prolonged half-life within the lung. These unique properties of the drug and the use of CT to discriminate attenuation levels provide a means of identifying patients with significant pulmonary accumulation of amiodarone.