[1] Ist Ospitalieri Cremona, Serv Terpie Intens, Cremona, Italy
[2] IRCCS Policlin San Matteo, Serv Biometria & Clin, Direz Sci, Pavia, Italy
[3] Ist Ospitalieri Cremona, Div Mallattie Infettive, Cremona, Italy
[4] Ist Nazl Malattie Infettive Lazzaro Spallazani, Div Malattie Infettive 2, Rome, Italy
[5] Univ Brescia, Spedali Civili, Ist Anestesia & Rianimaz, Serv Anestesia & Rianimaz 2, I-25100 Brescia, Italy