[1] Univ Hosp Copenhagen, Rigshosp, Dept Clin Immunol, Blegdamsvej 9, DK-2100 Copenhagen, Denmark
[2] Univ Hosp Copenhagen, Rigshosp, Dept Epidemiol Res, Statens Serum Inst,Dept Haematol, Copenhagen, Denmark
[3] Copenhagen Univ Hosp, Danish Headache Ctr, Dept Neurol Dept, Glostrup, Denmark
[4] Naestved Hosp, Dept Clin Immunol, Naestved, Denmark
[5] Univ Hosp Aarhus, Dept Clin Immunol, Aarhus, Denmark
[6] Odense Univ Hosp, Dept Clin Immunol, Odense, Denmark