The short stature homeobox-containing gene (SHOX) plays an important role in bone development and growth. We aimed to assess bone geometry and volumetric bone mineral density at the radius in patients with isolated SHOX deficiency and to relate these bone parameters to the severity of disproportion between the upper and the lower body segment. 17 patients with isolated SHOX deficiency (median age 12.3 yrs, range 6.7-37.2, 12 children and 5 adults) were examined by peripheral quantitative CT (pQCT) at the non-dominant forearm. Results were expressed as Z-scores using published reference data. Linear regression analyses were performed to describe associations between pQCT parameters and the severity of disproportion expressed as sitting height to standing subischial leg height ratio. Trabecular volumetric bone mineral density (vBMD) at the distal radius was normal, whereas cortical vBMD was decreased (mean Z-scores 0.34±1.5, n.s., and -2.2±2.2, p<0.001, respectively). Total bone cross-sectional area was enlarged at the diaphysis (2.1±1.2, p<0.001), while cortical bone cross-sectional area was normal (-0.51±1.4, n.s.). Consequently, cortical thickness was decreased (-1.2±1.3, p<0.01). The polar strength-strain index as a surrogate of long bone strength was normal (0.40±1.4, n.s.). We found no associations between pQCT parameters and the severity of disproportion. Conclusions: Patients with isolated SHOX deficiency are characterized by decreased cortical vBMD and cortical thickness and enlarged diaphysis. As similar changes have been described in girls with Turner syndrome, these findings suggest that haploinsufficiency of SHOX could cause characteristic skeletal anomalies at the radius.
- MeSH
- algoritmy MeSH
- diafýzy radiografie MeSH
- dítě MeSH
- dospělí MeSH
- haploinsuficience * MeSH
- homeodoménové proteiny genetika metabolismus MeSH
- kostní denzita MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- počítačová rentgenová tomografie MeSH
- poruchy růstu genetika metabolismus patofyziologie radiografie MeSH
- radius metabolismus radiografie MeSH
- stupeň závažnosti nemoci MeSH
- velikost těla MeSH
- vývoj dítěte * MeSH
- vývoj kostí * MeSH
- vývoj mladistvých * MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
CONTEXT: The low bone mineral density (BMD) and alterations in bone geometry observed in patients with Turner syndrome (TS) are likely caused by hypergonadotropic hypogonadism and/or by haploinsufficiency of the SHOX gene. OBJECTIVE: Our objective was to compare BMD, bone geometry, and strength at the radius between prepubertal girls with TS and children with isolated SHOX deficiency (SHOX-D) to test the hypothesis that the TS radial bone phenotype may be caused by SHOX-D. DESIGN AND SETTING: This comparative cross-sectional study was performed between March 2008 and May 2011 in 5 large centers for pediatric endocrinology. PATIENTS: Twenty-two girls with TS (mean age 10.3 years) and 10 children with SHOX-D (mean age 10.3 years) were assessed using peripheral quantitative computed tomography of the forearm. MAIN OUTCOMES: BMD, bone geometry, and strength at 4% and 65% sites of the radius were evaluated. RESULTS: Trabecular BMD was normal in TS (mean Z-score = -0.2 ± 1.1, P = .5) as well as SHOX-D patients (mean Z-score = 0.5 ± 1.5, P = .3). At the proximal radius, we observed increased total bone area (Z-scores = 0.9 ± 1.5, P = .013, and 1.5 ± 1.4, P = .001, for TS and SHOX-D patients, respectively) and thin cortex (Z-scores = -0.7 ± 1.2, P = 0.013, and -2.0 ± 1.2, P < .001, respectively) in both groups. Bone strength index was normal in TS as well as SHOX-D patients (Z-scores = 0.3 ± 1.0, P = .2, and 0.1 ± 1.3, P = .8, respectively). CONCLUSIONS: The similar bone geometry changes of the radius in TS and SHOX-D patients support the hypothesis that loss of 1 copy of SHOX is responsible for the radial bone phenotype associated with TS.
- MeSH
- aberace pohlavních chromozomů MeSH
- dítě MeSH
- genetické asociační studie MeSH
- genetické nemoci vrozené genetika metabolismus patologie patofyziologie MeSH
- haploinsuficience * MeSH
- homeodoménové proteiny genetika metabolismus MeSH
- kosti a kostní tkáň chemie patologie MeSH
- kostní denzita MeSH
- lidé MeSH
- mechanické jevy MeSH
- mladiství MeSH
- mutace MeSH
- poruchy růstu etiologie MeSH
- průřezové studie MeSH
- radius MeSH
- Turnerův syndrom genetika metabolismus patologie patofyziologie MeSH
- vývoj dítěte MeSH
- vývoj kostí * MeSH
- vývojové onemocnění kostí etiologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Geografické názvy
- Česká republika MeSH
