Furthermore, obvious positive correlations were observed among u/s ACE ratio, inflammatory cell infiltrates (r = 0.53, P = 0.044), and interstitial fibrosis (r = 0.56, P = 0.029) in the RS group.<h4>Conclusion</h4>u/s ACE ratio and sACE could be useful biomarkers for diagnosing RS in sarcoidosis and TIN, respectively. This evidence concerns the gene ACE and sarcoidosis.