Methotrexate로 치료받은 건선 환자에서의 간질성 폐렴 1예

Methotrexate (MTX) is commonly employed in the management of chronic inflammatory skin diseases. We report the case of a 73-year-old man who presented with a persistent cough lasting for 1 month. He had an 11-year history of psoriasis and had received MTX (10.0 mg/wk) over the past 21 months. High-resolution chest computed tomography revealed diffuse ground-glass opacities and bronchiectasis affecting both lung fields. Based on clinical and radiological assessments, the patient was diagnosed with MTX-induced interstitial pneumonia. Notably, significant clinical and radiological improvement was observed 1 month after the discontinuation of MTX and corticosteroid administration. Although some reports have demonstrated lung toxicity in patients receiving high-dose MTX therapy, cases of adverse pulmonary effects following low-dose treatment in patients with psoriasis are rare. This case report underscores the rarity of interstitial pneumonia in a patient with psoriasis undergoing MTX treatment in Korea.