ACE and sarcoidosis: Several biomarkers are determined in the standard diagnostic work-up and follow-up of patients with sarcoidosis, like serum angiotensin-converting enzyme (ACE) and soluble interleukin 2 receptor (sIL-2R) in serum, as well as lymphocytes and CD4+/CD8+ ratio in bronchoalveolar lavage [2–4].