Sarcoidosis is a systemic disorder with unknown etiology and pathogenesis characterized by non-caseating granulomas, and different clinical manifestations of sarcoidosis hinder diagnosis and treatment. Therefore, a comprehensive understanding of serological markers based on clinical observations of sarcoidosis and the progression of granulomas would aid analysis in routine clinical practice. In this review, we overview common serological markers, including angiotensin converting enzyme (ACE) and lysozyme, and describe in detail new promising indices in sarcoidosis such as a T cell serological marker (soluble interleukin 2 receptor; sIL-2R) and thymus and activation-regulated chemokine (TARC/CCL17).

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