Infliximab-induced pulmonary interstitial disease in a male patient with ulcerative colitis: a case report and review of literature.

Tumor necrosis factor-alpha (TNF-α) inhibitors, including infliximab, have redefined the treatment of inflammatory bowel diseases (IBD) such as ulcerative colitis (UC). Despite their efficacy, these agents are associated with rare but serious adverse events, including drug-induced interstitial lung disease (D-ILD). We report a case of infliximab-induced ILD in a 63-year-old male undergoing treatment for UC. The patient presented with fever, dyspnea, and a miliary hypersensitivity pattern on imaging. Infectious causes were excluded, and drug-induced pulmonary toxicity was diagnosed. Discontinuation of infliximab and appropriate management led to gradual clinical improvement. This case highlights the importance of early recognition and management of pulmonary complications associated with TNF-α inhibitors. Given that UC itself and other autoimmune diseases can predispose patients to ILD, we also explore the role of disease activity and additional risk factors, including prior exposure to 5-aminosalicylic acid-based medications. Endoscopic disease activity, fecal calprotectin levels, autoimmune markers (ANA, ENA, ANCA), and bronchoalveolar lavage results are provided to further elucidate the diagnostic process.