[Clinical analysis of 25 cases of biopsy-proven cryptogenic organizing pneumonia].

Objective: To analyze the clinical, radiological and pathological features, diagnosis and response to therapy as well as prognosis of 25 cases of cryptogenic organizing pneumonia (COP).

Methods: Twenty-five subjects with COP confirmed by lung biopsy in Shanghai Pulmonary Hospital from January of 2000 to April of 2006 were retrospectively reviewed. Secondary reaction to infections, drugs, radiation, connective tissue diseases and various noxious agents were excluded. Their clinical-pathological characteristics, radiological features, response to treatment, relapse, survival were obtained from medical records and a follow-up patient questionnaire.

Results: There were 6 males and 19 females, with a mean age of 56 years (range 40 - 73 years). The presentations included cough (25/25), clear sputum (21/25), dyspnea (17/25), hemoptysis (5/25), fever and sweats (3/25), and "Velcro" crackles (18/25). Four of them were smokers, 11 had allergic reaction to some drugs, and 11 had some industrious dust inhalation. In 23 cases the specimens were obtained by video-assisted thoracoscopy and 2 cases by transbronchial lung biopsy. Bilateral lung involvement was present in 23 cases and all of them had at least two different radiological manifestations. Twenty-four cases showed a sub-pleural distribution. Bilateral patchy alveolar and ground glass involvement were found in 8 cases, airspace consolidation in 8 cases, mass in 11 cases, irregular lines in 10 cases, small nodules (<10 mm) in 4 cases. Two patients received operation. Corticosteroid therapy was administered to 23 patients. Seventeen cases were cured, but 8 of them relapsed after stopping (n = 2) and tapering (n = 6, when prednisone less than 5 - 10 mg/d) of corticosteroids within one to two years of therapy.

Conclusions: COP is not very rare in China. The clinical-radiological-pathological diagnosis (CRP) is the most important diagnostic method. Corticosteroid is the first choice for COP therapy. The prognosis of COP is good if therapy is started in time, but relapse is common.