Amiodarone pulmonary, neuromuscular and ophthalmological toxicity: DISCUSSION (2)

AIPT occurs in 5% to 15% of patients on amiodarone and can be fatal in up to a third of those affected. Increasing age and pre-existing lung disease may predispose patients to AIPT, but no tests or clinical features can predict which patient will develop AIPT. The total cumulative dose, and higher daily maintenance doses, have been associated more consistently with an increased incidence of AIPT. However, pulmonary toxicity has been reported with short courses of low dose amiodarone.Noninvasive pulmonary investigations are not reliable predictors of the development of AIPT. However, a decrease in diffusing capacity by more than 20% should prompt closer investigation. Manifestations of AIPT described include bronchiolitis obliterans with or without organizing pneumonia, chronic interstitial pneumonitis with or without fibrosis, solitary or multiple pulmonary masses or adult respiratory distress syndrome. CT scans may reveal high attenuation lesions in the lung parenchyma as well as in the liver and spleen, reflecting the accumulation of iodine in these tissues.