pulmonary manifestations of Amiodarone toxicity

Q: 62 years old male with known cardiac disease and on prolonged Amiodarone therapy is admitted to ICU with syncope and third-degree AV block. Further workup also showed pulmonary manifestations of Amiodarone toxicity. All of the following can be pulmonary effects of chronic Amiodarone therapy EXCEPT?

A) nonproductive cough 

B) bilateral inspiratory crackles

C) clubbing 

D) fever

E) alveolar hemorrhage

Answer: C

Pulmonary toxicity is the most common side effect of long-term amiodarone therapy. It usually occurs in patients who are treated with ≥400 mg/day, particularly in patients with pre-existing lung disease. Conventionally, it is believed to occur after months or even years of therapy (with progressive cumulation of drug). Still, case reports are present in literature where pulmonary side-effects of Amiodarone therapy are reported within 2-3 weeks of treatment. 

Chronic interstitial pneumonitis is the most common pulmonary toxicity with symptoms of a nonproductive cough and dyspnea. Pleuritic pain, weight loss, fever, malaise, and bilateral inspiratory crackles may occur.

Eosinophilic pneumonia, organizing pneumonia, acute respiratory distress syndrome (ARDS), alveolar hemorrhage, and pulmonary nodules have been reported - but clubbing exclusively due to Amiodarone is still off the list.

#pulmonary

#pharmacology

#cardiology

References:

1. Dusman RE, Stanton MS, Miles WM, et al. Clinical features of amiodarone-induced pulmonary toxicity. Circulation 1990; 82:51.

Zimetbaum P. Amiodarone for atrial fibrillation. N Engl J Med 2007; 356:935.

2.Kwok WC, Ma TF, Chan JWM, et al. A multicenter retrospective cohort study on predicting the risk for amiodarone pulmonary toxicity. BMC Pulm Med 2022; 22:128.

3. Wolkove N, Baltzan M. Amiodarone pulmonary toxicity. Can Respir J 2009; 16:43.

4. Kharabsheh S, Abendroth CS, Kozak M. Fatal pulmonary toxicity occurring within two weeks of initiation of amiodarone. Am J Cardiol 2002; 89:896.