1 Department of Internal Medicine and Therapeutics, University of Pavia, Italy; Infectious Diseases Unit, IRCCS "San Matteo", Pavia, Italy.
2 Infectious Diseases Unit, IRCCS "San Matteo", Pavia, Italy.
3 Gastroenterologia Epatologia e Trapiantologia, Papa Giovanni XXIII Hospital, Bergamo, Italy.
4 Infectious Diseases Unit, IRCCS "San Matteo", Pavia, Italy; Department of Medical, Surgical, Diagnostic and Paediatric Science, University of Pavia, Pavia, Italy. Electronic address: raffaele.bruno@unipv.it.