DOI: https://doi.org/10.4414/smw.2019.20133
We thank Carratù et al. for their technical comment [1] on our publication about the effect of bosentan in patients with steroid-resistant pulmonary sarcoidosis [2]. The authors have shown previously that endothelin-1 (ET-1) urine levels were significantly higher in patients with active sarcoidosis as compared with healthy controls [3]. Furthermore, urine ET-1 levels decreased after prednisone treatment, which was paralleled by an improved clinical status [3]. Based on this observation the authors suggest measuring urine ET-1 levels before and after bosentan treatment, as this might be a prognostic factor.
The identification of specifically targetable traits in a complex disorder like sarcoidosis is of paramount importance. However, we would like to emphasise that the role of ET-1 urine levels in patients with sarcoidosis has not been elucidated yet and thus it is rather speculative to propose it as a prognostic tool. Neither has it been validated as a predictive tool. Moreover, based on our data [2] and on current knowledge there is no role for bosentan in the treatment of patients with steroid-resistant pulmonary sarcoidosis and thus the effect of bosentan on urine ET-1 levels in sarcoidosis patients does not seem of priority interest.
No financial support and no other potential conflict of interest relevant to this article was reported.
1 Carratù P , Dragonieri S , Resta O . Comment on: Hostettler K, et al. Bosentan for patients with steroid-resistant pulmonary sarcoidosis: a randomised controlled trial. Swiss Med Wkly. 2019;149:w20132. doi:https://doi.org/10.4414/smw.2019.20132
2 Hostettler K , Baty F , Kleiner R , Junker L , Tamm M , Brutsche M . Bosentan for patients with steroid-resistant pulmonary sarcoidosis: a randomised controlled trial. Swiss Med Wkly. 2018;148:w14677. doi:.https://doi.org/10.4414/smw.2018.14677
3 Sofia M , Mormile M , Faraone S , Alifano M , Carratù P , Carratù L . Endothelin-1 excretion in urine in active pulmonary sarcoidosis and in other interstitial lung diseases. Sarcoidosis. 1995;12(2):118–23.
No financial support and no other potential conflict of interest relevant to this article was reported.