[Clinical analysis of IgG4-related lung disease].

Objective: To improve the understanding and treatment of IgG4-related lung disease (IgG4-RLD) by analyzing the clinical characteristics of patients. Methods: A total of 13 patients with IgG4-related lung disease (IgG4-RLD) diagnosed by pathology at Zhongshan Hospital affiliated to Fudan University during December 2007 to December 2017 were included. The clinical characteristics, chest CT, pathological features, serum IgG4 levels, therapy and prognosis of these 13 patients were analyzed. Results: The 13 patients with IgG4-RLD included 8 men and 5 women, with an average age of (51.1±14.8) years. The clinical manifestations were varied, 10 patients showed respiratory symptoms, mainly including cough ( n =9), expectoration ( n =6), hemoptysis ( n =6), chest tightness ( n =2) and breathless ( n =2). Multiple organs were involved in 12 cases. Chest CT showed solid lung nodules ( n =9), ground glass shadows ( n =1), alveolar-interstitial infiltration ( n =3), bronchovascular lesions ( n =3), and the solid lung nodules was predominant. Enlargement of lymph nodes in the mediastinal and bilateral hilum of the lung were present in 10 cases. Serum IgG4 levels were elevated in all the 13 cases, with an average concentration of (7.92 ±13.98)g/L. Quite amount of lymphocytes, plasma cell infiltration and fibrosis were common pathologic findings. Immunohistochemical staining showed a large number of IgG4 positive plasma cells infiltration with IgG4 positive plasma cells count 10-320/HP in 13 cases. The ratio of IgG4 positive plasma cells to IgG positive plasma cells was higher than 40%. Eight patients received glucocorticoid therapy alone, five received glucocorticoids with immunosuppressant therapy. After treatment, 10 patients were with remission, and disease progressed in 3 patients, but no death. Conclusions: The clinical manifestations and imaging features of IgG4-RLD are diverse, and lesions can often involve multiple organs. The diagnosis could be made based on pathological features and IgG4 serum levels. Glucocorticoid can be used as the first choice for the treatment of IgG4-RLD.