[1] Univ Oslo, Rikshosp, Dept Cardiol, N-0027 Oslo, Norway
[2] Univ Oslo, Rikshosp, Internal Med Res Inst, N-0027 Oslo, Norway
[3] Univ Oslo, Rikshosp, Dept Clin Chem, N-0027 Oslo, Norway
[4] Univ Oslo, Rikshosp, Dept Pediat Res & Obstet & Gynecol, N-0027 Oslo, Norway
[5] Univ Oslo, Rikshosp, Dept Immunol, N-0027 Oslo, Norway
[6] Univ Oslo, Rikshosp, Sect Clin Immunol & Infect Dis, N-0027 Oslo, Norway