Urinary excretion of deoxypyridinoline in 24-hour and first-void samples in healthy Turkish children

Objectives: Collagen cross-links are formed during the maturation process o f bone matrix. They have been considered as valuable markers in some metabo lic, endocrinologic, and neoplastic bone disorders. As an advantage, it can be measured in urine as well as in serum samples. However, the excretion c haracteristics remains controversial. Design and methods: We investigated urinary free deoxypyridinoline (f-Dpd) excretion in first-void urine samples and in 24-hour collections in healthy Turkish children. We also evaluated the possible correlations and gender-r elated differences in Dpd excretion between these sampling methods. Both ur ine samples of 62 subjects (aged from 31 to 120 months) were analyzed by Im mulite chemiluminescent technique. Results: There were no remarkable differences in f-Dpd excretion between fi rst-void and 24-hour urine samples, although f-Dpd values of the first-void samples were slightly higher (Dpd: creatinine, mean +/- SD, 20.5 +/-; 5.8 nmol/mmol vs. 19.6 +/- 5.6 nmol/mmol, respectively, p > 0.05), A strong lin ear correlation was found between 24-hour and first-void urine f-Dpd excret ions (r = 0.77, p < 0.05). In addition, f-Dpd showed no gender-related diff erences between boys and girls in either 24-hour or first-void urine sample s (p > 0.05). Conclusions: Because of difficulties in long-time urine collection in infan ts and young children, f-Dpd assessment in first-void single urine samples is an easy, safe, and non-invasive method. Copyright (C) 2000 The Canadian Society of Clinical Chemists.