[1] San Matteo Hosp Fdn, Dept Infect Dis, Pavia, Italy
[2] Univ Pavia, Dept Clin Surg Diagnost & Pediat Sci, Via Palestro 3, I-27100 Pavia, Italy
[3] Klinikum Muenchen Perlach, Dept Med, Munich, Germany
[4] Univ Dusseldorf, Clin Gastroenterol Hepatol & Infect Dis, Trop Med, Dusseldorf, Germany
[5] Augusta Univ, Med Coll Georgia, Dept Emergency Med & Hospitalist Serv, Augusta, GA USA
[6] Kings Coll London, London WC2R 2LS, England
[7] San Bortolo Hosp, Infect & Trop Dis Unit, Vicenza, Italy
[8] Minneapolis Vet Affairs Hosp, Minneapolis, MN USA