Peter Blümel

Spontaneous growth in turner syndrome: Evidence for a minor pubertal growth spurt

Spontaneous growth of 141 untreated girls with Turner syndrome was analysed. Of the patients 25% were born prematurely; their weight and height were normal when compared to prematurely born healthy infants. However, birth weight and height was significantly retarded in Turner patients born at term. A curve for height and growth velocity for the age range 0–16 years was constructed with a sensitive statistical method. By use of a mathematical model equations were created for calculating z-scores and the related percentiles for the height of individual patients at given age. median height of 18 untreated patients at 18 years was 143.8 cm. Analysis of growth velocity revealed a minor but significant growth spurt at the age of 12.5 years. This growth spurt was also detectable in patients without signs of spontaneous puberty and occurred later in patients with 45,X0 karyotype. Bone age progression was linear up to the age of 7.5 years and decelerated thereafter.

Death in two female Prader-Willi syndrome patients during the early phase of growth hormone treatment

UNLABELLED Reports on sudden death in Prader-Willi syndrome (PWS) patients after the start of growth hormone (GH) treatment have been published recently. We observed a 4.7-y-old girl who showed a continuous increase in pulmonary artery pressure and died of cardiorespiratory failure 7 wk after GH therapy had been initiated, and a 9.3-y-old girl with additional trisomy 21 who died during a minor respiratory infection 6 mo after GH had been started. Both patients were overweight (weight for height 127% and 224%, respectively). GH-induced fluid retention may have occurred in the younger girl. In contrast to the reported cases, our PWS patients were female. CONCLUSION Our cases illustrate the difficulty of differentiation between possible GH side effects and the natural course of disease, in particular with respect to obesity-related comorbidity and mortality.

Treatment of patients with Ullrich-Turner syndrome with conventional doses of growth hormone and the combination with testosterone or oxandrolone: effect on growth, IGF-I and IGFBP-3 concentrations.

Thirty-nine girls with Ullrich-Turner syndrome (UTS) (median age 9.5 years) were treated with growth hormone (GH) with either 12 or 18 IU/m2 per week for 12 months followed by combination therapy with either oxandrolone (Ox) (0.0625 mg/kg/day po) or low-dose testosterone (T) (5 mg im every 2 weeks). Growth velocity improved significantly after 12 IU/m2 per week (6.4±1.7 cm/year vs 4.0±1.3 cm/year, x±SD,P<0.001) and 18 IU/m2 per week of GH (6.5±1.3 cm/year vs 4.5±1.4 cm/year,P<0.001). Ox, but not T was effective in maintaining growth velocity during the 2nd year of therapy (6.9±1.3 vs 5.3±1.5 cm/year). Basal insulin-like growth factor-I (IGF-I) concentrations were in the lower normal range and increased significantly in patients treated with 18 IU/m2 per week (357±180 ng/ml vs 160±84 ng/ml) and 12 IU/m2 per week (273±121 ng/ml vs 140±77 ng/ml). IGF-I concentrations increased further after addition of Ox (533±124 ng/ml,P<0.001) or T (458±158,P<0.05). IGFBP-3 concentrations were in the upper normal range before therapy and increased only moderately in both GH dosage groups. However, IGF binding protein-3 (IGFBP-3) concentrations were not affected by additional Ox or T treatment.Conclusions1. Conventional GH doses are effective in increasing growth velocity in UTS, especially, when combined with Ox. This additive effect is not evident when GH is combined with low dose T. 2. Changes in growth velocity are accompanied by an increase of the IGF-I/IGFBP-3 ratio. 3. Ox obviously acts by increasing IGF-I levels independent of the GH status.

Austrian height and body proportion references for children aged 4 to under 19 years

Abstract Background: Previous studies have demonstrated differences between national and the WHO reference curves in children older than 5 years. Moreover, reference curves for body proportions (sitting height, subischial leg length and their ratio) based on state-of-the-art statistics are not available. Aim: To develop reference curves for height and body proportions for use in Austria and compare the curves with WHO reference curves. To estimate and statistically investigate extreme percentiles. Subjects and methods: A sample of ∼14 500 children between 4–19 years of age was drawn via schooling institutions, stratified by provinces according to age- and sex-specific population proportions. GAMLSS models were used for a flexible estimation of percentile curves. Results and conclusions: After the age of 5 years national reference curves are more suitable than the WHO reference curves for clinical use in Austria. These height curves are very similar to the German reference curves published recently. Therefore, these reference curves for criteria of body proportions are recommended for use in other populations. Further validation studies are needed to establish whether the recently recommended −2.5 and −3.0 SD for height are a sensitive and specific cut-off in the diagnostic work-up for children with a suspected growth disorder using this new Austrian height chart.

Short- and Long-Term (Final Height) Growth Responses to Growth Hormone (GH) Therapy in Patients with Turner Syndrome: Correlation of Growth Response to Stimulated GH Levels, Spontaneous GH Secretion, and Karyotype

In 41 girls with Turner syndrome, the growth hormone (GH) peak values during stimulation tests and parameters of spontaneous nocturnal GH secretion were studied and compared with respect to different karyotypes, short-term growth response to GH therapy, and final height. 22.0% of the girls tested had a subnormal (peak < 11 ng/ml) and 9.7% a pathological (< 7 ng/ml) GH response. The spontaneous GH secretion showed a good correlation with the data of the provocation tests, providing no further information regarding GH capacity. Short-term growth response to GH treatment could not be predicted by any of the investigated parameters. Although patients with isochromosomes had frequent subnormal GH tests, their growth response to GH treatment after 1 year was comparable to that of girls with XO karyotype and mosaicism. In 18 patients who had reached final height, the height gain during treatment (calculated as final height minus projected adult height) was not different among patients with normal, subnormal, or pathological GH tests. In contrast, final height minus projected adult height in 4 girls with isochromosomes was 15.7 +/- 5.1 versus 7.6 +/- 3.3 cm in 14 patients with other karyotypes (p < 0.01). These girls had a more pronounced bone age delay (3.3 +/- 0.3 vs. 1.8 +/- 1.2 years) at the start of therapy and thus a better growth potential. We conclude that short- and long-term growth responses to GH treatment in Turner syndrome could not be predicted by GH testing. Patients with isochromosomes might represent a subpopulation which is more frequently GH deficient and shows a marked bone age delay.

Weight and body mass index (BMI): current data for Austrian boys and girls aged 4 to under 19 years

Abstract Background: BMI reference charts are widely used to diagnose overweight, obesity and underweight in children and adolescents. Aim: To provide up-to-date national reference values for Austria. Methods: A cross-sectional sample of over 14 500 children and adolescents (4–19 years) stratified by provinces according to age- and sex-specific population proportions was drawn via schooling institutions (kindergartens, schools and vocational colleges). The generalized additive models for location, scale and shape were used for a flexible estimation of percentile curves. Results: Austrian boys and girls have higher average weight compared with previous prevalence data. BMI centiles matching BMI values at age 18 years, which are used for defining thinness, overweight and obesity in adults, were calculated. In Austria, using reference values as thresholds, ∼18% of boys and 12% of girls are overweight (with thresholds passing through BMI 25.00–29.99 kg/m2 in adults) and 5% of boys and 3% of girls are obese (with thresholds passing through BMI ≥30.00 kg/m2 in adults). Conclusion: Overweight and obesity are common in Austria and their prevalence is increasing (using the same IOTF reference for international comparison). Up-to-date national BMI reference values are provided to classify children and adolescents according to the proposed overweight and obesity thresholds.

The influence of growth hormone monotherapy and growth hormone in combination with oxandrolone or testosterone on thyroxid hormone parameters and thyrxine binding globulin in patients with Ullrich- Turner syndrome

Abstract Administration of human growth hormone (GH) has yielded conflicting results concerning its role on thyroid function in patients with Ullrich-Turner syndrome. Therefore, we investigated the course of thyroid hormone parameters and thyroxin binding globulin in relation to GH therapy, IGF-I and additional oxandrolone-(Ox) or testosterone (T) treatment in 20 patients with Ullrich-Turner syndrome. During the 1st year the patients received only GH. There was no change in T4, fT4, and TSH levels, T3 increased significantly (P <  0.01) after 6 and 12 months, resulting in a higher T3/T4 ratio. TBG (P < 0.05) and IGF-I (P < 0.01) increased after 6 months and remained elevated at 12 months. A significant positive correlation was found between the change of T4 and TBG after 6 months (r = 0.47, P < 0.05) and after 12 months (r = 0.69, P < 0.005). Thirteen patients were further investigated after addition of an anabolic compound; 7 received Ox (0.0625 mg/kg/day po) and 6 low dose T (5 mg i.m. every 14 days). Chronological age was comparable in these groups (10.7 ±  2.7 vs 10.7  ± 3.6 years). After 6 months of combination therapy with Ox, T4, T3 and TSH decreased. As T4 and T3 showed a parallel decrease the T3/T4 ratio remained elevated. TBG declined after 6 and 12 months (P < 0.05), while IGF-I showed a further increment (P < 0.05). There was no correlation between the changes in T4 and IGF-I, TSH and TBG, respectively. In the T-treated group only IGF-I increased (P < 0.05) to the same extent as in the Ox-treated patients, whereas the thyroid parameters did not change. Conclusion The observed changes in thyroid hormone and TBG levels in the Ox group were not mediated by GH or IGF-I. The Ox-induced TBG decrease might be linked to altered pancreatic functions regulating carbo-hydrate metabolism.

Death in two female Prader-Willi syndrome patients during the early phase of growth hormone treatment: Clinical observations

Reports on sudden death in Prader‐Willi syndrome (PWS) patients after the start of growth hormone (GH) treatment have been published recently. We observed a 4.7‐y‐old girl who showed a continuous increase in pulmonary artery pressure and died of cardiorespiratory failure 7 wk after GH therapy had been initiated, and a 9.3‐y‐old girl with additional trisomy 21 who died during a minor respiratory infection 6 mo after GH had been started. Both patients were overweight (weight for height 127% and 224%, respectively). GH‐induced fluid retention may have occurred in the younger girl. In contrast to the reported cases, our PWS patients were female.