1. Medical Laboratory Osnabrueck, Georgsmarienhuette, Germany
2. Institute of Clinical Chemistry and Laboratory Medicine, Rostock University Medical Center, Rostock, Germany
3. Clinic of Internal Medicine I, University Clinics Leipzig, Leipzig, Germany
4. Department of Internal Medicine, Neurology and Dermatology, Clinic and Policlinic of Gastroenterology, Hepatology Section, Leipzig, Germany
5. Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, Leipzig, Germany