[1] Kecioren Training & Res Hosp, Dept Dermatol, Ankara, Turkey
[2] Gulhane Mil Med Acad, Dept Cardiol, Etlik, Turkey
[3] Gulhane Mil Med Acad, Dept Internal Med, Etlik, Turkey
[4] Gulhane Mil Med Acad, Dept Clin Chem, Etlik, Turkey
[5] Gulhane Mil Med Acad, Dept Epidemiol, Etlik, Turkey
[6] UCL, Sch Med, Dept Clin Chem, London W1N 8AA, England