Evaluation of a fully automated assay to measure c-telopeptide of type I collagen in serum

The measurement of the degradation product of the C-telopeptide of type I c ollagen in serum (s-beta CTX) has been evaluated in the form of an automate d chemiluminometric assay. The between-day coefficients of variation ranged between 2.6 and 6.0% over the concentration range 0.12 to 3.25 mug/l. The s-beta CTX value correlated well with alternative serum C-telopeptide (r = 0.983) and urine deoxypyridinoline (r = 0.729) measurements. A significant inverse correlation was found between the s-beta CTX measurement and creati nine clearance in patients with renal disease.