Biomedical subjects

Silvano Bertelloni

Publications and source records attributed to Silvano Bertelloni.

6 recordsLinked to original sources

PubMed2003

Assessment of bone quality by quantitative ultrasound of proximal phalanges of the hand and fracture rate in children and adolescents with bone and mineral disorders.

Bone quality by quantitative ultrasound and fracture rate were assessed in 135 (64 males) children and adolescents aged 3-21 y with bone and mineral disorders such as chronic anticonvulsants or glucocorticoids treatment, juvenile rheumatoid arthritis, celiac disease, paucity of intrahepatic bile ducts, autoimmune hepatitis, genetic diseases, idiopathic juvenile osteoporosis, disuse osteoporosis, beta-thalassemia major, survivors of acute lymphoblastic leukemia, liver transplantation, calcium deficiency, and nutritional or X-linked hypophosphatemic rickets. Amplitude-dependent speed of sound through the distal end of the first phalangeal diaphysis of the last four fingers of the hand was measured by an ultrasound device. In the majority of patients cortical area to total area ratio by metacarpal radiogrammetry (n = 120) and lumbar bone mineral density (BMD) by dual-energy x-ray absorptiometry (n = 99) were also assessed. In patients with X-linked hypophosphatemic rickets radial BMD by single-photon absorptiometry instead of lumbar BMD was measured. Mean values of amplitude-dependent speed of sound, cortical area to total area ratio, lumbar BMDarea, or lumbar BMD corrected for bone sizes estimated by a mathematical model (BMDvolume), as well as mean values of radial BMD in patients with X-linked hypophosphatemic rickets, expressed as z score, were significantly reduced (p < 0.0001) in comparison with their reference values (-1.7 +/- 1.0, -2.0 +/- 0.9, -3.0 +/- 1.3, -1.9 +/- 1.0, -2.7 +/- 0.7, respectively). A positive relationship was found between amplitude-dependent speed of sound and cortical area to total area ratio (r = 0.90, p < 0.0001), lumbar BMDarea (r = 0.62, p < 0.0001), or lumbar BMDvolume (r = 0.66, p < 0.0001). Fifty-two patients (38.5%) had suffered fractures in the 6 mo preceding the bone measurements, the radial distal metaphysis being the most frequent fracture site (28.8%). Mean values of amplitude-dependent speed of sound, cortical area to total area ratio, lumbar BMDarea, or lumbar BMDvolume, expressed as z score, of fractured patients were significantly lower (p < 0.0001) than those of fracture-free patients (-2.2 +/- 1.0 and -1.4 +/- 0.8, -2.6 +/- 0.9 and -1.7 +/- 0.7, -3.5 +/- 1.2 and -2.5 +/- 1.0, -2.5 +/- 1.0 and -1.3 +/- 0.7, respectively). Phalangeal quantitative ultrasound may be a useful method to assess bone quality and fracture risk in children and adolescents with bone and mineral disorders.

Adolescent↗

PubMed2003

Growth and puberty in Turner's syndrome.

Turner's syndrome is the commonest sex chromosome abnormality in females, resulting from the absence of an X chromosome or the presence of a structurally abnormal X chromosome. Short stature and ovarian failure are the most consistent clinical features and require specific and co-ordinated medical approaches in order to improve final height and well-being in adulthood. High doses of growth hormone (GH) are able to improve adult height in comparison with untreated patients. GH therapy should be started during childhood as soon as the growth curve declines below the 5th percentile and doses adjusted according to clinical response. Some studies reported that combined therapy with GH and an anabolic steroid--oxandrolone--is also beneficial at lower GH doses. Ovarian failure should be treated by appropriate substitutive estrogen therapy. Since estrogen administration may impair growth of patients with Turner's syndrome, the age at beginning of therapy should be individualized taking into consideration potential growth, the need for feminization, bone mineral density and the psychological well-being of each patient. Well co-ordinated endocrine interventions can permit better long-term outcome in adulthood.

Anabolic Agents↗

PubMed2003

Acquisition of bone mass in normal individuals and in patients with growth hormone deficiency.

Children and adolescents with growth hormone (GH) deficiency (GHD) have reduced bone turnover and bone mass in comparison with normal individuals. GH replacement therapy stimulates bone turnover and improves bone mass during childhood and adolescence. At final height, patients with GHD treated with GH have normal mean values of bone mass, but some patients have reduced lumbar BMD (Z score <1) with an increased susceptibility to fractures. Children and adolescents with GHD have approximately a fourfold decreased fracture frequency during treatment in comparison with controls. The changes of bone mass during the transition to adulthood in patients with GHD who discontinued GH treatment after final height are not defined. An increase of lumbar BMD after final height has been reported until 2 years after discontinuation of GH treatment; this could be the result of a spontaneous progression towards peak bone mass or of a persisting effect of GH treatment on bone mass accumulation. GH has an important role in the accrual of bone mass during childhood and adolescence, but the impact of GHD on bone mass during the transiton to adulthood is unknown.

Aging↗

PubMed2003

Effects of thalassemia major on bone mineral density in late adolescence.

Management of thalassemia major has shown substantial clinical and prognostic improvement, suggesting the need for major attention to quality of life. We studied bone health in 25 patients (13 males, 12 females; 15-23 years old) affected by beta-thalassemia major. In all patients, bone mineral density (BMD), biochemical markers of bone and calcium metabolism (calcium, phosphate, magnesium, alkaline phosphatase, urinary calcium, 25-hydroxyvitamin D [25OH-D], 1,25-dihydroxyvitamin D [1,25(OH)2D], parathyroid hormone [PTH]), hematological parameters and gonadal steroids status were assessed and related to each other and to auxological parameters (chronological, statural and bone ages, height, weight, stage of puberty). BMD of the lumbar spine (L1-L4) (g/cm2) and expressed as Z-scores, was assessed by dual energy X-ray absorptiometry. PTH levels were low in seven patients (28%), and in the normal range in 18 (72%). 25OH-D serum levels were normal in 16 patients (64%) and low in nine (36%). 1,25(OH)2D values were reduced in 19 patients (76%) and normal in six (24%). Alkaline phosphatase correlated with bone age delay (r = 0.414; p = 0.039); no other statistically significant correlation was found. Mean BMD values in patients with thalassemia were significantly reduced in comparison with that of age- and sex-matched controls (Z-score: -2.8 +/- 2.0, p <0.001; -3.3 +/- 2.1 in males, and -2.2 +/- 1.9 in females). Twenty-one patients (84%) showed reduced BMD. Overall, BMD reduction was in the osteopenia range in five patients (20%) and in the osteoporosis range in 16 patients (64%). Our data indicate that low BMD is often present in patients with thalassemia, although recognized late, as in the present series. Early diagnosis should be done during childhood, in order to improve the quality of life in adulthood.

Adolescent↗

PubMed2002

Puberty and bone development.

Puberty has a key role for bone development. Skeletal mass approximately doubles at the end of adolescence. The main determinants of pubertal gain of bone mass are the sex steroids, growth hormone and insulin-like growth factors (by their effects on bone and muscle mass), 1,25-dihydroxyvitamin D (by stimulating calcium absorption and retention) and muscle mass (by regulating modelling/remodelling thresholds). Calcium intake is an additional factor influencing bone formation. The interactions among these factors are undefined. The accrual of bone mass during puberty is a major determinant of peak bone mass and, thereby, of the risk of osteoporotic fractures during advanced age.

Adolescent↗

PubMed2002

Lumbar bone mineral density at final height and prevalence of fractures in treated children with GH deficiency.

Lumbar bone mineral density (BMD) by dual energy x-ray absorptiometry was assessed in 46 (29 boys, 17 girls) treated patients with growth hormone deficiency (GHD) at final height, comparing the BMD results with normative data. Prevalence of fractures in patients during treatment and healthy controls (n = 100) during the corresponding time period was assessed. Lumbar BMD values at final height of fractured and fracture-free patients were compared between them. Lumbar BMD corrected for bone area was significantly (P < 0.01) reduced (boys, -0.4 +/- 0.8 Z score; girls, -0.5 +/- 0.7 Z score), but lumbar BMD corrected for bone size (BMDvolume) did not differ [P = not significant (NS); boys -0.2 +/- 1.0 Z score; girls, -0.3 +/- 1.0 Z score] from normal mean. Approximately 22% of patients had reduced lumbar BMD (Z score, -1 to -2). The fact that patients had a complete or partial GHD did not influence lumbar BMD. The prevalence of fractured patients did not differ (P = NS) from that of controls [n = 7 (15.2%) and n = 24 (24.0%), respectively; odds ratio, 1.837]. Lumbar BMDvolume of fractured patients was significantly (P < 0.02) lower than that of fracture-free (n = 39) patients (boys, 0.310 +/- 0.005 and 0.351 +/- 0.032 g/cm(3), respectively; girls, 0.326 +/- 0.027 and 0.382 +/- 0.036 g/cm(3), respectively). The percentage of the fractured patients with lumbar BMDvolume less than 1 SD of normal mean was significantly (P < 0.0001) higher than that of fracture-free patients [n = 6 (85.7%) and n = 4 (10.3%), respectively; odds ratio, 26.092). The fractured patients also showed reduced lumbar BMD corrected for bone area and BMDvolume at the time of fractures (-1.6 +/- 0.4 and -1.5 +/- 0.2 Z score, respectively). The results show that treated patients with GHD have normal mean values of lumbar BMDvolume at final height, but some patients have reduced lumbar BMD (Z score <1) with an increased susceptibility to fractures.

Adolescent↗