Research progress on sarcoidosis

Sarcoidosis is a multisystem inflammatory disease of unknown etiology and pathogenesis, pathologically characterized by noncaseating granulomas. But many new recognitions are acquired in recent years, especially on genetic and immunological factors. For example, the relationship between human leukocyte antigen HLA DRB1 gene polymorphism and pathogenesis, the effects of chemokines such as CCL15 on the development of this disease. Many new techniques are used for the diagnosis process to obtain pathologic result. The significance of lymphocyte count and CD4/CD8 ratio in bronchoalveolar lavage fluid is more definite in diagnosis and differential diagnosis, The corticosteroids and immunosuppressive agents are still the first choice to treat the disease. But based on the adverse effect of corticosteroids and the new knowledge about etiology and pathogenesis, some new therapies, such as anti-tumor necrosis factor-α, have become new choices on treating rapid progressing and/or refractory sarcoidosis and achieved encouraging results. This article summaries the above progress. Key words: Sarcoidosis ;  Pathogenesy;  Diagnosis;  Treatment