Alterations of a serum marker of collagen X in growing children with osteogenesis imperfecta

Collagen X Biomarker (CXM), Linear Growth, and Bone Development in a Vitamin D Intervention Study in Infants

“…The growth rate during the second year of life becomes more stable and variability in dietary factors, motor skill milestones, and other external factors are likely smaller than during the first year of life. Interestingly, the association between CXM and linear growth was weaker in this study compared with previous reports, (2,22,23) especially among infants. The repeated measurement of both CXM and height velocity in the same individuals over a longer period of time during childhood performed in previous studies most likely explains the stronger associations reported elsewhere.…”

“…The repeated measurement of both CXM and height velocity in the same individuals over a longer period of time during childhood performed in previous studies most likely explains the stronger associations reported elsewhere. In our study, however, the variation in CXM values was larger (2-137 ng/mL) compared with previous studies by Coghlan and colleagues (20-95 ng/mL), (2) by Nicol and colleagues (10-95 ng/mL) (22) in subjects of comparable ages, and by Welborn and colleagues (4-47 ng/mL) (23) among subjects with ages 7 to 16 years of age. The numbers of normal-growth children aged 12 and 24 months from this study are higher than those among children in the same age range in the reference study by Coghlan and colleagues.…”

“…In general, in the few studies conducted, CXM concentrations followed a pattern of a higher concentration during early childhood, subsequently declining but peaking again at the age of puberty. (2,22,23) A higher vitamin D supplementation dose slightly increased CXM and modified the association between CXM and linear growth. However, the clinical importance of these findings remains unclear.…”

“…In children with osteogenesis imperfecta, the association between CXM and growth showed a weaker correlation than that among healthy children, indicating less accuracy as a biomarker of osteogenesis imperfecta as a skeletal abnormality. (22) However, an interesting potential exists particularly in later childhood or during puberty when an individual decline in CXM may indicate growth cessation and provide a tool for patient monitoring. (23) Our rare sample of healthy infants and toddlers experiencing rapid growth phase provides important knowledge on the usability of CXM as an indicator of early childhood linear growth and bone development.…”

“…In general, in the few studies conducted, CXM concentrations followed a pattern of a higher concentration during early childhood, subsequently declining but peaking again at the age of puberty. ( 2,22,23 )…”