Markers of bone metabolism in children with rickets

Abstract

The problem of rickets remains relevant due to the widespread prevalence of the disease and unsatisfactory results of diagnosis and treatment. Objective. To identify changes in the biochemical parameters of bone metabolism and to establish their relationship with the clinical condition of children with rickets. Materials and methods . The authors conducted a simultaneous controlled clinical comparative study of 108 children aged from 5 months to 2 years. C-terminal telopeptide of type I collagen (CrossLaps), calcitriol, calcitonin, osteocalcin, and blood osteoprote-gerin were analyzed by the enzyme-linked immunosorbent assay method. The level of calcium was determined by colorimetric method, phosphorus — by photometric test. Alkaline phosphatase activity was evaluated in blood serum by an optimized kinetic method. Results . We determined a decrease in the level of serum calcitriol, calcitonin, calcium and phosphorus, as well as an increase in the concentration of the C-terminal telopeptide of type I collagen, osteocalcin, parathyroid hormone, osteoprotegerin, acid and alkaline phosphatase activity. The greatest increase in the level of osteoprotegerin was recorded in children with the II degree of rickets, both in acute and subacute course. The concentration of osteocalcin was increased in all groups of patients with the highest values in patients with the II degree of rickets, regardless of the course of the disease. The activity of acid phosphatase in the blood of patients was also increased. A decrease in the concentration of calcitriol, calcitonin, calcium and phosphorus in the blood was observed in all groups of children with rickets. Conclusion. The authors recorded the correlations between the studied indicators of bone metabolism in patients with rickets. An increase in the level of osteoprotegerin is apparently a new link in the pathogenesis of rickets.