Amiodarone-Induced Pulmonary Toxicity With Severe Pulmonary Fibrosis Complicated by Stenotrophomonas maltophilia Pneumonia: A Fatal Case Report and Literature Review

Amiodarone is a widely used antiarrhythmic agent, valued for its efficacy and low proarrhythmic risk, but it carries a known potential for serious toxicities, particularly pulmonary toxicity. Amiodarone-induced pulmonary toxicity (APT) remains a life-threatening adverse effect. We report the case of a 75-year-old male with a 30-year history of amiodarone use (200 mg twice daily) who developed progressive respiratory distress consistent with APT. Despite treatment with broad-spectrum antibiotics and corticosteroids, his condition deteriorated. Imaging and clinical findings raised suspicion for APT, which was managed with amiodarone discontinuation and pulse-dose steroid therapy. Subsequently, he developed hospital-acquired <i>Stenotrophomonas maltophilia</i> pneumonia, a multidrug-resistant opportunistic infection. Targeted antibiotics were initiated based on sensitivities, but the patient progressed to respiratory failure and multiorgan dysfunction, ultimately resulting in death. This case highlights the diagnostic and therapeutic challenges of managing APT, particularly in elderly patients on long-term therapy. The absence of standardized pulmonary surveillance and delayed recognition can result in advanced disease at presentation. Superimposed nosocomial infections, especially with resistant organisms such as <i>S. maltophilia</i>, further complicate outcomes. Clinicians must maintain a high index of suspicion for APT in patients presenting with unexplained respiratory symptoms while on amiodarone. This case underscores the importance of appropriate dosing, consistent outpatient monitoring, and prompt evaluation for opportunistic infections in the setting of clinical deterioration.