1. School of Medicine, University of Pavia, 27100 Pavia, Italy
2. Department of Infectious Disease, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milan, Italy
3. School of Medicine and Surgery, University of Milano-Bicocca, 20126 Milan, Italy
4. Intensive Care Unit, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milan, Italy