1. Departments of Clinical Chemistry (E.C., M.-L.S., R.G.), B-4000 Liège, Belgium
2. Endocrinology (D.B., L.V., A.F.D., A.B.), B-4000 Liège, Belgium
3. Nephrology (P.D.), Centre Hospitalier Universitaire de Liège, University of Liège, B-4000 Liège, Belgium