Successful salvage treatment of steroid-refractory bronchiolar COP with low-dose macrolides

Cryptogenic organizing pneumonia (COP) is an idiopathic interstitial pneumonia characterized by fibroblastic tissues that occupy the lumina of alveoli and alveolar ducts or respiratory bronchioles. Although adequate doses and durations of glucocorticoids can improve its condition, COP is sometimes resistant to glucocorticoid therapy and is often lethal.Herein, a very rare case of 'bronchiolar COP' that was confined to the respiratory bronchioles is reported. This case indicates that macrolides may act as anti-inflammatory agents in patients with COP. Timely and precise pathological diagnosis may corroborate clinician diagnoses and eventually improve chances to overcome the disease.