Dosage de la calcitonine sérique sur Advantage® (Nichols). Bilan de quatre ans d'utilisation. Définitions de valeurs usuelles en fonction de l'âge et du sexe

The authors describe four years of serum calcitonin assay using Nichols Advantage® system, and supply usual values according to age and sex. Analytical results are in agreement with Nichols specifications. Reproductibility observed over a 17 months period (N =160) is: 11.3, 9.8 et 7.1%, respectively for 5, 20 et 190 ng/l. Results were a little modified by two technical evolutions (April 2002 and September 2003). About usual values, our results confirm limited reported data obtained using obsolete methods: the usual values of calcitonin are much higher in infants, especially those aged less than six months, than in adults. In our adult population, calcitonin concentrations were higher in men. This difference, which is underlined by the manufacturer, has not been taken into account in current consensus values. We suggest the following normal values:  <40 ng/l up to six months,  <15 ng/l between six months and three years,  <5 ng/l in females over the age of three years and <10 ng/l in males over the age of three years.