Biomedical subjects

G Saggese

Publications and source records attributed to G Saggese.

At least 73 records · Page 4Linked to original sources

PubMed1997

Bone demineralization in cystic fibrosis: evidence of imbalance between bone formation and degradation.

Bone turnover, collagen metabolism, and bone mineral status were investigated in 59 patients with cystic fibrosis and in 72 sex and age-matched control subjects. In all patients and control subjects serum concentrations of osteocalcin (OC), carboxy-terminal propeptide of type I procollagen (PICP), amino-terminal propeptide of type III procollagen (PIIINP), and cross-linked carboxy-terminal telopeptide of type I collagen (ICTP), and urinary values of cross-linked N-telopeptides of type I collagen (NTX), as well as total body bone mineral content (TBBM) were measured. Higher ICTP (microgram/L) and NTX (bone collagen equivalent/urinary creatinine (nmol/mmol) values were found in pre-pubertal, pubertal, and young adult patients than in control subjects (ICTP: 15.4 +/- 2.1 and 13.2 +/- 1.8, p < 0.001; 23.3 +/- 5.3 and 20.1 +/- 4.1, p < 0.02; 4.8 +/- 1.1 and 4.0 +/- 1.0, p < 0.05. respectively; NTX: 1047.5 +/- 528.6 and 227.8 +/- 71.8, p < 0.01; 997.8 +/- 391.7 and 376.3 +/- 91.0, p < 0.01; 993.2 +/- 398.0 and 73.9 +/- 28.5, p < 0.01, respectively). Lower OC and PICP levels (microgram/L) were showed in pubertal patients in comparison with control subjects (OC: 20.2 +/- 12.3 and 39.0 +/- 15.1, p < 0.01; PICP: 305.8 +/- 130.4 and 436.2 +/- 110.1, p < 0.02, respectively). Lower OC and higher PIIINP levels (microgram/L) were found in young adult patients than in control subjects (OC: 4.4 +/- 3.0 and 7.0 +/- 3.1, p < 0.05; PIIINP: 4.8 +/- 1.1 and 3.1 +/- 1.0, p < 0.001, respectively). TBBM (z score) was reduced in prepubertal, pubertal, and young adult patients (-0.8 +/- 0.4, -1.0 +/- 0.4, -1.1 +/- 0.5, respectively). Patients with cystic fibrosis have bone demineralization and imbalance between bone formation and degradation.

Adolescent↗

PubMed1996

Central precocious puberty in Klinefelter syndrome: a case report with longitudinal follow-up of growth pattern.

We report idiopathic central precocious puberty in a boy with Klinefelter syndrome and describe the pattern of linear growth and body proportion from the onset of precocious puberty to final height. The patient was not treated for precocious puberty. He reached adequate adult height, for both general population and normative values of Klinefelter syndrome and normal body proportions. We conclude that precocious puberty in Klinefelter syndrome may result in normal body proportion by inducing a major growth spurt of the trunk rather than in the limbs, and that adult height prognosis is not altered by precocious puberty. Given the possible occurrence of precocious puberty in Klinefelter syndrome, we advise a karyotype analysis in boys with sexual precocity, mainly in those who show small rather than enlarged testes.

Body Constitution↗

PubMed1996

Bone mineral density in adolescent females treated with L-thyroxine: a longitudinal study.

UNLABELLED: It has been suggested that chronic treatment with L-thyroxine (L-T4) could be implicated in reducing bone mineral density (BMD). The purpose of this longitudinal study was to determine whether appendicular and axial BMD is decreased by L-T4 treatment in adolescent girls. Thirteen adolescent girls with subclinical hypothyroidism caused by chronic lymphocytic thyroiditis were enrolled in the study at the median age of 13.4 years (range 9.2-18.1 years). L-T4 was administered in a single dose of 1-5 micrograms/kg daily. BMD was evaluated at the distal one-third of the non-dominant radius by single photon absorptiometry (SPA) and at the lumbar spine (L2-4) by dual energy X-ray densitometry (DEXA). Osteocalcin levels were measured to assess bone turnover before and during L-T4 treatment. Before the start of therapy, mean BMD at both the radial and lumbar level was not significantly different from that of a control group (median age 13.0 years; range 9.0-18.5 years). during L-T4 therapy for 2-5 years, BMD did not change at any site. Before treatment, osteocalcin levels were not significantly different from those of controls and did not change during follow up. CONCLUSION: Long-term L-T4 therapy in adolescent girls has no adverse effect on BMD and bone turnover. Our data indicate that attainment of peak bone mass is not impaired by L-T4 administration.

Absorptiometry, Photon↗

PubMed1996

Bone mineral density and biochemical parameters of bone turnover in children with growth hormone deficiency.

Growth hormone (GH) is a crucial factor in the build-up and in the maintenance of peak bone mass. Children with GH deficiency have osteopenia and a concomitant reduction in bone turnover. On the other hand, GH therapy improves bone mineral density and stimulates bone turnover. These data suggest that GH treatment may have a beneficial effect on peak bone mass. In children with GH deficiency, the values of some biochemical markers of bone turnover may be closely related to growth response during GH therapy. However, further studies are needed to define the usefulness of bone markers in order to optimize the treatment and to predict the growth outcome in GH-treated children.

Biomarkers↗

PubMed1996

The effect of long-term growth hormone (GH) treatment on bone mineral density in children with GH deficiency. Role of GH in the attainment of peak bone mass.

The effect of long-term GH treatment on bone mass was examined in 32 children with GH deficiency (GHD) aged 7.2-16.3 yr by measuring radial (distal third, single-photon absorptiometry) and lumbar (L2-L4, dual energy x-ray absorptiometry) bone mineral density (BMD) (group A). All patients were longitudinally followed and received recombinant hGH therapy for a mean period of 48.2 +/- 13.2 months. BMD values were corrected for bone age and expressed as Z-score in comparison with normative data. In addition, lumbar BMD and lumbar BMD corrected for the estimated vertebral volumes were assessed in 11 patients with GHD aged 16.0 - 18.7 yr at the time they reached their final height (group B) and, in 17 subjects with familial short stature aged 16.4 - 19.8 yr, as controls (group C) for patients of group B. Patients of group B had received discontinuous treatment with pituitary-derived hGH and subsequently recombinant hGH (total duration of treatment 151.5 +/- 9.7 months). The off-treatment period was 4.7 +/- 2.6 months. Before treatment, patients of group A showed significantly reduced (P < 0.001) radial and lumbar BMD (-1.7 +/- 0.4 Z-score and -1.5 +/- 0.5 Z-score, respectively) compared with normative data. During treatment, radial and lumbar BMD Z-scores improved significantly (P < 0.001); in the patients treated for the longest time, the BMD was within 0.5 SD of age-matched mean levels. In patients of group B, lumbar BMD and lumbar BMD corrected for the estimated vertebral volumes were significantly reduced in comparison with subjects of group C (-1.2 +/- 0.4 Z-score and -1.0 +/- 0.4 Z-score, P < 0.01 and P < 0.03, respectively). The results show that children with GHD have reduced BMD. Optimal GH treatment improves BMD, whereas inappropriate treatment is a main cause of reduced BMD at time of final height. These findings suggest an important role of GH therapy in the attainment of peak bone mass in children with GHD. GH treatment should be continued until the attainment of peak bone mass irrespective of the height achieved.

Adolescent↗

PubMed1996

Testosterone-induced increase of insulin-like growth factor I levels depends upon normal levels of growth hormone.

Pubertal development is associated with a rise in plasma insulin-like growth factor I (IGF-I) levels that is related both to the increase in sex steroids and/or to the sex steroid-induced augmentation in endogenous growth hormone (GH) secretion. In order to investigate the relationship between IGF-I, GH and testosterone, we examined 42 male subjects with various clinical conditions (classical GH deficiency (CGHD, N = 5), non-classical GH deficiency (NCGHD, N = 7), short idiopathic stature (N = 6), nutritional obesity (N = 8), GH-treated CGHD (N = 4), GH-treated NCGHD (N = 5) and normal stature (N = 7)) in which , for evaluation of hypogonadism (i.e. the absence of one or both testes from the scrotal sac), human chorionic gonadotropin (hCG) tests were performed. We measured IGF-I, total and free testosterone and dehydroepiandrosterone sulfate (DHEAS) by radioimmunoassays before and 48 and 96 h after the start of the test. The values of IGF-I were lower (0.001 < p < 0.005) in CGHD and NCGHD than in the other groups. In comparison to basal levels, IGF-I values increased (0.005 < p < 0.05) both 48 and 96 h after the start of the hCG test in short idiopathic and normal stature children and in GH-treated subjects with NCGHD, but only 96 h in subjects with untreated NCGHD and GH-treated CGHD. No difference was demonstrated in basal values of total testosterone among any of the groups, while basal free testosterone levels were higher (0.001 < p < 0.05) in GH-treated subjects with NCGHD than in all the other groups except nutritional obesity; furthermore, free testosterone was higher (p < 0.05) in nutritional obesity than in CGHD. The values of total and free testosterone obtained both 48 and 96 h after the start of the hCG test were higher (0.001 < p < 0.05) than basal values in all groups. The DHEAS values did not show any significant change during the hCG test. Basal values were higher (0.01 < p < 0.05) in nutritional obesity than in the other groups. Considering all groups, chronological age, bone age and bone age/chronological age ratio were correlated with basal free testosterone, IGF-I and DHEAS levels (0.001 < p < 0.05), while basal free testosterone and IGF-I values were correlated with DHEAS levels (p < 0.005 and < 0.01, respectively). In conclusion, our study during the hCG test in boys with various clinical conditions demonstrated an increase in IGF-I concentrations only in those boys with sufficient GH secretion or GH replacement therapy. These findings indicate that both sex steroids and GH are necessary to allow for the pubertal increase in IGF-I levels.

Body Height↗

PubMed1995

Short-term effect of testosterone treatment on reduced bone density in boys with constitutional delay of puberty.

We studied bone mineral content (BMC), bone mineral density (BMD), cortical thickness/total width (CT/TW) ratio and cortical area/total area (CA/TA) ratio in boys with constitutional delay of puberty and the effect of short-term testosterone treatment on bone mass. Seventeen boys (age 13.1-15.8 years) who met the family history and the clinical criteria of constitutional delay of puberty were selected and enrolled in the study. All subjects were eating a diet assuring an adequate intake of calories and calcium. A subset of 8 boys (group A) was treated with testosterone depot (100 mg/month x 6 months) while 9 boys (group B) were not. At inclusion, BMC and BMD were reduced in the patients according to their chronological age (BMC -4.04 +/- 1.34 standard deviation scores [SDS]; BMD -2.95 +/- 0.56 SDS), statural age (BMC -1.75 +/- 0.79 SDS; BMD -1.69 +/- 0.78 SDS), and bone age (BMC -1.80 +/- 0.65 SDS; BMD -1.86 +/- 0.68 SDS). No significant differences between the groups were found (group A: BMC 0.480 +/- 0.57 g/cm, BMD 0.488 +/- 0.037 g/cm2, CT/TW ratio 0.43 +/- 0.4, CA/TA ratio 0.68 +/- 0.04; group B: BMC 0.476 +/- 0.060, p = NS vs. group A; BMD 0.491 +/- 0.036 g/cm2, p = NS vs. group A). At 12 months of follow-up, BMC, BMD, CT/TW ratio, and CA/TA ratio significantly increased in group A (BMC 0.70 +/- 0.13 g/cm, delta +41.1 +/- 28.8%, p < 0.003 vs. 0 month; BMD 0.617 +/- 0.082 g/cm2, delta +26.2 +/- 13.6%, p < 0.005 vs. 0 month; CT/TW ratio 0.52 +/- 0.05, delta +20.59 +/- 10.65%, p < 0.001 vs. 0 month; CA/TA ratio 0.77 +/- 0.05 vs. 0 month; CT/TW ratio 13.60 +/- 6.65%, p < 0.004 vs 0 month), but not in group B (BMC: 0.48 +/- 0.05 g/cm; delta +5.1 7.8%, p = NS vs. 00 month; BMD: 0.492 +/- 0.037 g/cm2; delta +0.54 +/- 8.7%, p = NS vs. 0 month; CT/TW ratio 0.44 +/- 0.04, delta +4.04 +/- 6.75%, p = NS vs. 0 month; CA/TA ratio 0.68 +/- 0.05, delta +2.39 +/- 5.90%, p = NS vs. 0 month). We conclude that boys with constitutional delay of puberty have reduced BMC and BMD. The delay in statural and bone ages did not totally account for the decreased bone mass. Testosterone treatment for 6 months significantly increased BMC, BMD, CT/TW ratio, and CA/TA ratio in these patients, but definitive conclusions on the efficacy of the treatment in improving adult bone mass can be drawn only when our patients reach early childhood.

Adolescent↗

PubMed1995

Association between X-linked hypophosphatemic rickets and Klinefelter's syndrome: effects on growth and body proportion.

Growth failure with disproportionate short stature is the major clinical feature of patients with X-linked hypophosphatemic rickets (HYP). We studied the pattern of linear growth and body proportion in an untreated normally growing HYP child also affected by Klinefelter's syndrome. Auxologic data were compared with those of a HYP half-brother who showed growth failure despite long-term treatment either with vitamin D or with vitamin-D-analog plus phosphate salt supplementation. The degree of body disproportion changed from negative values to positive values in the proband, whereas it was reduced in the half-brother. We conclude that, in the proband, the normal pattern of growth and the lack of the typical body disproportion as seen in HYP patients are attributable to the concomitant presence of Klinefelter's syndrome.

Adolescent↗

PubMed1995

Long-term growth hormone treatment in children with renal hypophosphatemic rickets: effects on growth, mineral metabolism, and bone density.

OBJECTIVE: To evaluate the effects of treatment with recombinant human growth hormone (rhGH) on growth, mineral metabolism, and bone density in children with renal hypophosphatemic rickets (RHR). DESIGN: Long-term rhGH treatment combined with conventional therapy with 1,25-dihydroxyvitamin D3 plus inorganic phosphate salts. SETTING: Endocrine unit, department of pediatrics, university hospital. SUBJECTS: Twelve patients (5 boys; age range 4.6 to 12.5 years, median 7.0 years) were subdivided into two groups of six patients on the basis of the median of height z score (-2.41) and the median bone age/statural age (BA/SA) ratio (1.23). Group A included patients with a severe degree of short stature (height z score -3.4 +/- 0.5) (mean +/- SD) and altered BA/SA ratio (1.26 +/- 0.08); group B included patients with a lesser degree of short stature (height z score -2.1 +/- 0.6, p < 0.001 vs group A) and more normal BA/SA ratio (1.04 +/- 0.15, p < 0.01 vs group A). INTERVENTION: Group A received rhGH treatment (0.6 IU/kg per week subcutaneously) combined with conventional therapy; group B received conventional therapy alone. MEASUREMENTS: Height, growth velocity, predicted adult height, serum values of calcium, phosphate, bone alkaline phosphatase isoenzyme, osteocalcin, propeptides of type I and type III procollagen, intact parathyroid hormone, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and urinary calcium/urinary creatinine ratio and tubular maximum for phosphate reabsorption normalized to the glomerular filtration rate (TmP/GFR), as well as radial bone density, were measured at baseline and for 3 years. RESULTS: Height z score, growth velocity z score, predicted adult height, serum values of phosphate, bone alkaline phosphatase isoenzyme, osteocalcin, propeptides of type I and type III procollagen, intact parathyroid hormone 1,25-dihydroxyvitamin D, and TmP/GFR, as well as radial bone density, improved significantly only in group A. Serum calcium and 25-hydroxyvitamin D, and urinary calcium/urinary creatinine ratio did not change in either group. CONCLUSIONS: Long-term rhGH administration may benefit growth, phosphate retention, and bone density in patients with RHR, without evidence of side effects.

Bone Density↗

PubMed1995

Combination treatment with growth hormone and gonadotropin-releasing hormone analogs in short normal girls.

To improve final adult height, we treated with growth hormone (0.65 +/- 0.07 (mean +/- SD) IU.kg-1.wk-1) and gonadotropin-releasing hormone analogs (66 +/- 9 micrograms.kg-1 every 28 days) a group of seven short normal girls in early puberty with a chronologic age (CA) of 11.50 +/- 0.95 years, predicted adult height (PAH) lower (0.003 < p < 0.001) than mean target height, and without any endocrine abnormalities. The results were compared with those obtained in a similar group of seven untreated girls considered as control subjects. The mean period of combined therapy was 2.01 +/- 0.52 years; in two subjects treatment is still in progress. The value of height standard deviation score for bone age (BA) improved from -1.69 +/- 0.47 to -1.04 +/- 0.56 (p = 0.001); height age (HA)/BA ratio also increased from 0.83 +/- 0.05 to 0.90 +/- 0.04 (p < 0.01), as did PAH (from 146.8 +/- 4.4 to 152.9 +/- 3.6 cm; p < 0.002). The ratio of gain in HA to gain in BA was 2.08 +/- 0.78. Pubertal stages showed an arrest in five cases and a regression in the other two girls. After administration of gonadotropin-releasing hormone analogs was interrupted, in four of five girls growth hormone was administered alone for a further period of 6 to 18 months to improve their physiologic growth spurt. The present height in five girls is higher than PAH before therapy. In the treated girls the height values for BA, for BA/CA and HA/BA ratios, and for PAH were higher (0.002 < p < 0.04) than those in control subjects. This preliminary study demonstrates that combination therapy with growth hormone and gonadotropin-releasing hormone analogs in short, endocrinologically normal girls may be useful in improving both height prognosis and predicted adult height. Further studies are necessary to reach definitive conclusions regarding the efficacy of this kind of therapy.

Adolescent↗

PubMed1995

Effect of combined treatment with gonadotropin releasing hormone analogue and growth hormone in patients with central precocious puberty who had subnormal growth velocity and impaired height prognosis.

Growth hormone-insulin-like growth factor-I status and response to growth hormone therapy (0.6 IU/kg/week sc, six times a week for 12 months) were evaluated in 12 girls (chronological age 9.4 +/- 1.6 years) suffering from central precocious puberty with growth velocity less than 4 cm/year and no substantial increase or decrease in predicted adult height during gonadotropin releasing hormone Bn-RH) analogue treatment (D-Trp6-LH-RH, 60 micrograms/kg im/28 days). At baseline, large variations were observed in nocturnal growth hormone (GH) means (pathological values stimulated levodopa GH peaks (pathological values (< 10.0 micrograms/l) 28.6%) and serum insulin-like growth factor-I (IGF-I) levels. Neither GH-nor IGF-I levels were correlated with growth velocity. During recombinant GH therapy, growth velocity increased significantly (baseline 3.0 +/- 0.9 cm/year; 6 months 6.4 +/- 1.9 cm/year, p < 0.001 versus baseline; 12 months 6.0 +/- 1.3 cm/year, p < 0.0001 versus baseline). There was a significant increase in height SDS for bone age (baseline -1.6 +/- 0.5 SDS; 12 months -1.04 +/- 0.6 SDS; p < 0.002) and in predicted adult height (baseline 152.0 +/- 3.6 cm; 12 months 155.9 +/- 3.4 cm; p < 0.002). Our results suggest that combined therapy with Gn-RH analogues and recombinant GH can improve growth velocity and predicted adult height in girls with central precocious puberty and impaired height prognosis during Gn-RH analogue treatment.

Age Determination by Skeleton↗

PubMed1995

Use of combined Gn-RH agonist and hGH therapy for better attining the goals in precocious puberty treatment.

We studied 30 girls (age 6.36 +/- 1.21 years, range 4.6-8.8) affected by idiopathic precocious puberty with significant reduction of height velocity (below the 25th centile) at the end of 1 year of Gn-RHa (triptorelin intramuscular depot) treatment, to evaluate GH-IGF-I axis activity and the effects of combined Gn-RHa plus hGH therapy. After 12 months, 15 patients continued Gn-RHa and started hGH therapy for 12 months, while 15 continued treatment with Gn-RHa alone (control group). We evaluated height velocity, bone age, urinary GH, serum IGF-I and IGFBP-3 levels throughout the study; plasma GHBP levels were determined only in the first 12 months of Gn-RHa treatment. Height velocity decreased significantly during Gn-RHa treatment; it increased significantly and became higher than the control group after 12 months of Gn-RHa plus hGH treatment. During Gn-RHa therapy alone, bone age progressed less than chronological age, while in the 12 months of Gn-RHa plus hGH treatment there was a slight nonsignificant increase in bone age progression in comparison to controls. Serum IGF-I and IGFBP-3 levels decreased significantly at 12 months of Gn-RHa therapy and increased significantly after Gn-RHa plus hGH treatment. Urinary GH levels showed the same behavior. Plasma GH binding to peak II-BP, slightly lower than the prepubertal normal range before treatment, significantly increased after 12 months of Gn-RHa treatment. Therefore, in these girls, during Gn-RHa treatment alone, we have a reduction in GH-IGF-I axis activity. During Gn-RHa plus hGH therapy there was a significant increase in height velocity, in urinary GH levels, in serum IGF-I and IGFBP-3 levels. Bone age did not seem to advance faster than chronological age and this may imply a better prediction in adult height. In our opinion, only in a small percentage of patients affected by precocious puberty (with a very low predicted adult height or an important reduction of growth velocity during Gn-RHa treatment) may an association with hGH therapy be useful.

Body Height↗

PubMed1995

Effects of growth hormone on phosphocalcium homeostasis and bone metabolism.

In this review the effects of growth hormone (GH) on phosphocalcium homeostasis and bone metabolism are reported. Some in vitro effects of GH on chondrocytes and osteoblasts are discussed too. The main GH effects on phosphocalcium homeostasis are the permissive action on renal 1 alpha-hydroxylase activity by the hypophosphatemic stimulus and the antiphosphaturic effect by the stimulation of the maximum rate of renal tubular reabsorption of phosphate. On bone, GH is able to stimulate bone turnover and to increase bone mass. In addition, GH stimulates type I and type III collagen metabolism. In vitro, GH increases the proliferation of chondrocytes from the human growing cartilage together with the levels of interleukin-6 in the supernatant. The hormone increases also the proliferation of the human osteosarcoma-derived osteoblast-like cells and augments the osteocalcin levels in the supernatant. Thus, GH markedly influences phosphocalcium homeostasis and bone metabolism in childhood and adolescence. In addition, it is possible that GH continues to play a role in bone physiology during adulthood when final height is reached.

Animals↗

PubMed1995

Plasma growth hormone-binding protein activity, insulin-like growth factor I, and its binding protein levels in patients with Turner's syndrome: effect of short- and long-term recombinant human growth hormone administration.

Plasma growth hormone-binding protein (GH-BP) activity and the levels of IGF-I and its binding proteins (IGFBP) were studied in eight girls with Turner's syndrome before and during recombinant-hGH (r-hGH) administration. Growth hormone and GH-BP activity were assayed at baseline and hourly, over a 12-h period, after an intramuscular bolus of 0.09 mg/kg of the hormone. After 7 d, each patient received r-hGH at 0.33 mg/kg/weekly s.c. every day at nighttime; plasma growth hormone-binding protein activity, blood IGF-I, and IGFBP were evaluated before and on d 7, 30, 180, and 360. Baseline reference values were obtained from 10 bone age-matched healthy girls. Basal GH-BP activity, IGF-I, and IGFBP levels were similar in patients and controls. Four h after the intramuscular injection, GH-BP activity maximally increased and returned to baseline 6-7 h later; during long-term r-hGH administration GH-BP activity peaked at +180 d but declined to pretreatment at +360 d. IGF-I, IGFBP-3, and IGFBP-4 increased under r-hGH and, in contrast to GH-BP activity, remained high throughout the study. In conclusion, in girls with Turner's syndrome, GH-BP activity, IGF-I, IGFBP-3, and IGFBP-4 are induced by r-hGH. However, the increase of IGF-I and IGFBP-3 does not require an increased level of the cellular growth hormone receptors, as suggested by the unchanged +360 d values of plasma GH-BP activity compared with baseline.(ABSTRACT TRUNCATED AT 250 WORDS)

Carrier Proteins↗

PubMed1995

Nutritional aspects of calcium and vitamin D from infancy to adolescence.

Calcium is an essential nutrient for normal growth and development. Growing individuals must be in positive calcium balance to satisfy their calcium needs. Calcium requirements are higher during infancy and adolescence than childhood and adulthood. The achievement of a higher calcium balance in infancy and adolescence is likely due to the increased serum 1,25-dihydroxyvitamin D concentration occurring during these periods. The main determinants of calcium balance in infancy are dietary calcium intake and vitamin D. In normal circumstances, breast milk and formulas supply sufficient amounts of calcium. In the post-natal life, the major sources of vitamin D are sunlight exposure and supplemented formulas; in fact, the amount of vitamin D in breast milk, cow's milk, and common foods is poor. Although sunlight exposure should be able to maintain adequate vitamin D stores, a supplement with 400 IU/day of vitamin D from birth to the second year of life is recommended to assure the prophylaxis of rickets in all breast-fed infants. A dose of 400 IU/day of vitamin D is safe and appropriate. During childhood and adolescence, currently recommended dietary allowances (RDA) for calcium might be augmented, as suggested by calcium balance studies. The higher amount of calcium intake may lead to achieve maximal peak bone mass. The main source of vitamin D in children and adolescents is the casual sunlight exposure; therefore, a sistematical vitamin D supplementation is not usually needed. The major sources of calcium are milk and dairy products. However, if calcium intake is reduced, an additional calcium intake to reach the RDA may be provided by calcium supplements.

Adolescent↗

PubMed1994

Parathyroid hormone-related protein in healthy pregnant women.

The object of this study was to determine whether increased circulating levels of parathyroid hormone-related protein (PTH-rp) may explain the increased parathyroid hormone (PTH) bioactivity in pregnancy. In 41 healthy pregnant women (age 19-41 years), PTH-rp and corrected calcium levels were measured and compared with those of nonpregnant control women (n = 18, age 20-39 years). PTH-rp and corrected calcium levels were significantly higher in pregnant women (PTH-rp 21.9 +/- 7.9 pg/ml, P < 0.001; corrected calcium 2.38 +/- 0.07 mmol/liter, P = 0.001) than in nonpregnant women (PTH-rp 10.3 +/- 7.8 pg/ml; corrected calcium 2.30 +/- 0.10 mmol/liter). Our data indicate that circulating PTH-rp levels may significantly increase in pregnancy, suggesting a possible role of this peptide in the modification of calcium homeostasis in pregnant women.

Adult↗

PubMed1994

Growth hormone secretion in poorly growing children with renal hypophosphataemic rickets.

We evaluated growth hormone (GH) secretion and baseline serum free insulin-like growth factor-I (IGF-I) levels in 12 poorly growing patients (5 males and 7 females; age 1.6-12.5 years, median 6.4) with renal hypophosphataemic rickets treated with 1,25-dihydroxy-vitamin D3 plus inorganic oral phosphate salts. Eleven healthy normally growing children (6 males and 5 females; age 3.1-10.8 years, median 6.6) were studied as control group. All patients had a normal GH response (GH peak > or = 10 micrograms/l) to at least one provocative pharmacological stimulus (levodopa or insulin tolerance test), as well as all the controls. Mean growth hormone concentrations (MGHC), mean pulse amplitude, number of GH peaks above 5 micrograms/l, and IGF-I values overlapped between patients and controls, even though four patients had MGHC below the lower limit of MGHC of controls. In these patients, however, height-SDS, serum calcium, phosphate, alkaline phosphatase, intact parathyroid hormone, 1,25-dihydroxyvitamin D concentrations and maximum tubular phosphate reabsorption/glomerular filtration rate ratio did not differ in respect to the patients who showed MGHC in the range of controls (n = 6). MGHC IGF-I and biochemical parameters of phospho-calcium metabolism did not differ when the patients were subdivided in two groups on the basis of the median (-2.4) of height-SDS. No relationship was found between MGHC or IGF-I and height-SDS or growth velocity-SDS. Height-SDS and years of treatment or age at which therapy was started were not related.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗

PubMed1994

Twenty-four-hour osteocalcin, carboxyterminal propeptide of type I procollagen, and aminoterminal propeptide of type III procollagen rhythms in normal and growth-retarded children.

The relationships between spontaneous variations in serum 24-h osteocalcin (OC), carboxyterminal propeptide of type I procollagen (PICP), and aminoterminal propeptide of type III procollagen (PIIINP) concentrations and GH secretion, measured as GH response to provocative pharmacologic stimuli and spontaneous GH secretion during 24 h, were evaluated in prepubertal normal children and in GH-deficient and GH-secreting short normal children (SNC). All the subjects showed a circadian rhythm in smoothed 24-h OC and PICP mean data with higher nocturnal values in comparison with diurnal values. Conversely, serum PIINP concentrations did not vary throughout the day. In children with classic GH deficiency and nonclassic GH deficiency, mean 24-h serum levels and smoothed 24-h mean data for OC, PICP, and PIIINP were significantly reduced (p < 0.001) with respect to age-matched controls. SNC showed mean 24-h OC concentrations similar (p = NS) to those we found in age-matched controls, but they had significantly lower (p < 0.001) diurnal 12-h mean data in comparison with controls. SNC also showed both 24-h PICP and PIIINP mean data and smoothed 24-h PICP and PIIINP mean data significantly lower (from p < 0.02 to p < 0.001) at all the time points of measurement in comparison with controls. Twenty-four-hour PICP and PIIINP mean data were positively related to spontaneous 24-h GH concentrations (r = 0.77, p < 0.005 and r = 0.69, p < 0.005, respectively) and growth velocity (r = 0.85, p < 0.005, and r = 0.70, p < 0.005, respectively), whereas 24-h OC mean data were not.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Determination by Skeleton↗