1 Respiratory Diseases and Lung Transplantation, Department of Medical and Surgical Sciences & Neurosciences, University of Siena, Siena, Italy. david.btt@gmail.com.
2 Respiratory Diseases and Lung Transplantation, Department of Medical and Surgical Sciences & Neurosciences, University of Siena, Siena, Italy.
3 Internal Medicine, Department of Medical and Surgical Sciences & Neurosciences, University of Siena, Siena, Italy.