Diagnosis of hypochondroplasia: the role of radiological interpretation. Italian Study Group for Hypochondroplasia.

Background: Hypochondroplasia is characterised by phenotypic and genetic heterogeneity. Differentiation from other conditions with disproportionate short stature is often difficult.

Objective: To determine the reliability of radiological interpretation in the diagnosis of hypochondroplasia and to evaluate the most typical skeletal abnormalities.

Urinary markers of bone turnover in healthy children and adolescents: age-related changes and effect of puberty.

During growth, bones change their dimensions rapidly with the changes involving both formation and resorption processes. Small cross-linked peptides coming from type I collagen molecules are excreted in urine when bone is resorbed. To date, conflicting results have been presented concerning the age- and puberty-related changes of urinary markers.

Comparison of clinical-radiological and molecular findings in hypochondroplasia.

Hypochondroplasia is an autosomal dominant skeletal dysplasia characterized by disproportionate short stature. A mutation (N540K) in the fibroblast growth factor receptor 3 (FGFR3) gene was described in some patients with this condition. The aims of the study were to identify the frequency of the FGFR3 gene mutation, to define the salient clinical and radiological abnormalities of the affected subjects, and to verify the contribution of molecular findings to the clinical and radiological definition of hypochondroplasia.

Bone turnover in neonates: changes of urinary excretion rate of collagen type I cross-linked peptides during the first days of life and influence of gestational age.

New markers have been used to monitor the changes of bone turnover occurring during growth. Data on bone turnover rate during the perinatal period are, however, very scarce. In the present study we evaluated bone turnover rate, assessed by the measurement of urinary N-terminal telopeptide of type I collagen (NTx) concentrations, at different gestational ages, and we documented the trend of bone turnover rate occurring in the first days after birth.