[1] S Karelia Cent Hosp, Dept Internal Med, Lappeenranta 53130, Finland
[2] Univ Helsinki, Dept Bacteriol & Immunol, Haartman Inst, Helsinki, Finland
[3] Univ Helsinki, Cent Hosp, HUSLAB, Helsinki, Finland
[4] Jyvaskyla Cent Hosp, Dept Internal Med, Jyvaskyla, Finland
[5] Kuopio Univ Hosp, Dept Internal Med, SF-70210 Kuopio, Finland
[6] Univ Helsinki, Cent Hosp, Dept Med, Helsinki, Finland