Procollagen I carboxyterminal propeptide (PICP) as a bone formation marker and carboxyterminal telopeptide of type I collagen (ICTP) as a bone degradation marker in children with chronic renal failure under conservative therapy.

Background: Biochemical and hormonal disturbances in calcium-phosphate storage accompanying chronic renal failure (CRF) lead to the loss of bone mass and the destruction of bone microarchitecture. The aim of this study was to evaluate the serum levels of PICP (procollagen I carboxyterminal propeptide) and ICTP (carboxyterminal telopeptide of type I collagen) as markers of bone growth in CRF children treated conservatively.

Material/methods: 34 children (16 female and 18 males) with predialytic CRF, aged 6 to 18 years (average age 11.3+/-3.8 years) were included in the experimental group. The controls were 20 healthy age-matched children. The experimental subjects were divided into two subgroups, based on the blood level of intact PTH (iPTH). Subgroup Ia (n=7) consisted of children with normal serum concentrations of iPTH. Subgroup Ib (n=27) consisted of children with elevated serum concentrations of iPTH.

Results: In group Ia characteristic correlations were found between OST (osteocalcin) and ICTP, and between creatinine and ICTP. In group Ib, positive correlations were found between iPTH and PICP, iPTH and ICTP, OST and ICTP, and ICTP and PICP. In this group no correlation was found between marker turnover and creatinine.

Conclusions: The results of our study of PICP and ICTP as markers of bone metabolism in children with CRF in the predialysis period indicate that their levels should be routinely monitored as specific biochemical parameters of bone structure.