1. Department of Medicine and Surgery, Respiratory Disease and Lung Function Unit University of Parma Parma Italy
2. Department of Food and Drug University of Parma Parma Italy
3. Center for the Diagnosis of Inherited Alpha1‐Antitrypsin Deficiency, Department of Internal Medicine and Therapeutics, Pneumology Unit University of Pavia Pavia Italy
4. Unit of Respiratory Diseases, Department of Medical Sciences and Infective Diseases IRCCS Policlinico San Matteo Foundation Pavia Italy
5. Department of Medicine and Surgery University of Parma Parma Italy
6. Department of General and Specialistic Medicine University‐Hospital of Parma Parma Italy