TY - JOUR T1 - Pulmonary Toxicity After Initiation of Azathioprine for Treatment of Interstitial Pneumonia in a Patient with Rheumatoid Arthritis JF - The Journal of Rheumatology JO - J Rheumatol SP - 1104 LP - 1105 DO - 10.3899/jrheum.111415 VL - 39 IS - 5 AU - TAKAAKI ISHIDA AU - TAKUYA KOTANI AU - TOHRU TAKEUCHI AU - SHIGEKI MAKINO Y1 - 2012/05/01 UR - http://www.jrheum.org/content/39/5/1104.abstract N2 - To the Editor:Pulmonary involvement of rheumatoid arthritis (RA) includes drug-induced pulmonary toxicity, interstitial pneumonia (IP) due to RA itself, airway lesions, pleural lesions, and pulmonary infections due to the use of immunosuppressants. It is sometimes difficult to differentiate between these conditions. Pulmonary toxicity has been reported to be often induced by methotrexate and leflunomide but rarely by azathioprine (AZA). We describe a patient with RA and IP, in whom AZA induced pulmonary toxicity.The patient was a 72-year-old man diagnosed with RA (Steinbrocker stage III, class 2), treated with 5 mg/day prednisolone (PSL) and with clinically low disease activity. He developed a nonproductive cough 2 years ago. Chest radiograph and high-resolution computed tomography (HRCT) of the chest at that time revealed ground-glass opacities (GGO) in the bilateral peripheral lung fields and honeycomb-like cysts in the dorsal side of both lower lung fields, leading to a diagnosis of IP. Pulmonary function tests showed a vital capacity (VC) of 99.3%, and DLCO 54.2%.After he developed exertional dyspnea (Hugh-Jones Grade II) in March 2006, he was referred to our hospital and was admitted on June 20, 2006. Fine crackles were audible in both lower lung fields. Blood tests showed a white blood cell … Address correspondence to Dr. Ishida; E-mail: t-takeuchi{at}poh.osaka-med.ac.jp ER -