[1] Univ Modena & Reggio Emilia, Policlin, Dept Med Sci, Sect Hematol, I-41100 Modena, Italy
[2] Univ Modena & Reggio Emilia, Dept Pathol, I-41100 Modena, Italy
[3] Univ Liverpool, Dept Med Microbiol & Genitourinary Med, Liverpool L69 3BX, Merseyside, England
[4] Univ Brescia, Div Nephrol, Brescia, Italy
[5] Univ Minnesota, Dept Microbiol, Minneapolis, MN 55455 USA