A case of clopidogrel-induced organizing pneumonia evaluated by lung biopsy and confirmed by accidental re-administration

Clopidogrel-induced interstitial lung disease (ILD) is a rare but significant adverse effect. Herein, we report a case of organizing pneumonia following clopidogrel administration, confirmed by histopathology and accidental re-administration, fulfilling Camus’s criteria for drug-induced ILD. The patient responded well to corticosteroid therapy. A systematic literature review identified nine additional cases, with clinical presentations ranging from ground-glass opacities to eosinophilic infiltration. Most cases involved immune-mediated mechanisms. This report highlights the diagnostic challenges of clopidogrel-induced ILD and underscores the importance of considering drug etiology in organizing pneumonia. • We reported the case of clopidogrel-induced interstitial lung disease (ILD) in which both surgical lung biopsy and accidental re-administration confirmed the diagnosis. The definitive identification of clopidogrel as the causative agent provides new insight into the pathogenesis of clopidogrel-related pulmonary toxicity. • Chest CT and histopathological findings demonstrated an organizing pneumonia pattern, and the disease recurred rapidly after clopidogrel re-administration. These clinical features strongly support an immune-mediated mechanism rather than cytotoxic lung injury. • A systematic review of the literature identified nine previous cases of clopidogrel-induced ILD, revealing variable onset timing and radiologic patterns but overall favorable outcomes when the drug was discontinued and corticosteroid therapy was initiated. This case underscores the importance of considering DILD when organizing pneumonia develops in patients receiving clopidogrel.