69 research outputs found
Central precocious puberty and gonadotropin releasing hormone agonist treatment
In order to understand the processes occurring during precocious puberty, one
needs to specify what is currently known about normal pubertal development.
Puberty can be defined as a maturational process of the hypothalamic-pituitarygonadal
axis, which results in the development of the gonads and,
concomitantly, in the physical and physiological processes which constitute
adulthood and the capacity to reproduce.
The regulation of puberty is a very complex process, involving the hormonal
interaction of the cells in the hypothalamus, pituitary and gonads. A central role
in this process is played by the Gonadotropin Releasing Hormone (GnRH or
LHRH: Luteinizing Hormone Releasing Hormone) which is produced and
secreted by the hypothalamus
Pubertal development in The Netherlands 1965-1997
We investigated pubertal development of 4019 boys and 3562 girls >8 y of
age participating in a cross-sectional survey in The Netherlands and
compared the results with those of two previous surveys. Reference curves
for all pubertal stages were constructed. The 50th percentile of Tanner
breast stage 2 was 10.7 y, and 50% of the boys had reached a testicular
volume of 4 mL at 11.5 y of age. Median age at menarche was 13.15 y. The
median age at which the various stages of pubertal development were
observed has stabilized since 1980. The increase of the age at stage G2
between 1965 and 1997 is probably owing to different interpretations of
its definition. The current age limits for the definition of precocious
are close to the third percentile of these references. A high agreement
was found between the pubic hair stages and stages of pubertal (genital
and breast) development, but slightly more in boys than in girls.
Menarcheal age was dependent on height, weight, and body mass index. At a
given age tall or heavy girls have a higher probability of having menarche
compared with short or thin girls. A body weight exceeding 60 kg (+1 SDS),
or a body mass index of >20 (+1 SDS), has no or little effect on the
chance of having menarche, whereas for height such a ceiling effect was
not observed. In conclusion, in The Netherlands the age at onset of
puberty or menarche has stabilized since 1980. Height, weight, and body
mass index have a strong influence on the chance of menarche
Agricultural Microcredit and Household Vulnerability in Rural Malawi
textabstractSixteen girls with Turner syndrome (TS) were treated for 4 years with biosynthetic growth hormone (GH). The dosage was 4IU/m2 body surface s.c. per day over the first 3 years. In the 4th year the dosage was increased to 61 U/m2 per day in the 6 girls with a poor height increment and in 1 girl oxandrolone was added. Ethinyl oestradiol was added after the age of 13. Mean (SD) growth velocities were 3.4 (0.9), 7.2 (1.7), 5.3 (1.3), 4.3 (2.0) and 3.6 (1.5) cm/year before and in the 1st, 2nd, 3rd and 4th year of treatment. Skeletal maturation advanced faster than usual in Turner patients especially in the youger children. Although the mean height prediction increased by 5.6 cm and 11 of the 16 girls have now exceeded their predicted height, the height of the 4 girls who stopped GH treatment exceeded the predicted adult height by only 0 to 3.4 cm
Novel Clinical Criteria Allow Detection of Short Stature Homeobox-Containing Gene Haploinsufficiency Caused by Either Gene or Enhancer Region Defects
Introduction: Short stature homeobox-containing gene (SHOX) haploinsufficiency is associated with short stature, Madelung deformity and mesomelia. Current clinical screening tools are based on patients with intragenic variants or deletions. However, recent discoveries showed that deletions of the enhancer elements are quite common. The majority of these patients show less body disproportion and respond better to recombinant human growth hormone treatment. We redefined clinical criteria for genetic analysis to facilitate detection of the full spectrum of SHOX haploinsufficiency. Methods: We analyzed 51 children with SHOX variants or deletions and 25 children with a deletion in its enhancer region. Data were compared to 277 children referred for suspicion of growth failure without endocrine or genetic pathology. Results: Only half of the patients with an enhancer region deletion fulfilled any of the current screening criteria. We propose new clinical criteria based on sitting height to height ratio >1 SDS or arm span ≥3 cm below height, with a sensitivity of 99%. When these criteria are combined with obligatory short stature, the sensitivity to detect SHOX haploinsufficiency is 68.1%, the specificity 80.6%, and the number needed to screen 21 patients. Conclusion: Novel clinical criteria for screening for SHOX haploinsufficiency allow the detection of patients within the full genetic spectrum, that is, intragenic variants and enhancer region deletions
A randomized controlled trial of three years growth hormone and gonadotropin-releasing hormone agonist treatment in children with idiopathic short stature and intrauterine growth retardation
We assessed the effectiveness and safety of 3 yr combined GH and GnRH
agonist (GnRHa) treatment in a randomized controlled study in children
with idiopathic short stature (ISS) or intrauterine growth retardation
(IUGR). Gonadal suppression, GH reserve, and adrenal development were
assessed by hormone measurements in both treated children and controls
during the study period. Thirty-six short children, 24 girls (16 ISS/8
IUGR) and 12 boys (8 ISS/4 IUGR), with a height SD score of -2 SD or less
in early puberty (girls, B2-3; boys, G2-3), were randomly assigned to
treatment (n = 18) with GH (genotropin 4 IU/m(2). day) and GnRHa
(triptorelin, 3.75 mg/28 days) or no treatment (n = 18). At the start of
the study mean (SD) age was 11.4 (0.56) or 12.2 (1.12) yr whereas bone age
was 10.7 (0.87) or 10.9 (0.63) yrs in girls and boys, respectively. During
3 yr of study height SD score for chronological age did not change in both
treated children and controls, whereas a decreased rate of bone maturation
after treatment was observed [mean (SD) 0.55 (0.21) 'yr'/yr vs. 1.15
(0.37) 'yr'/yr in controls, P < 0.001, girls and boys together]. Height SD
score for bone age and predicted adult height increased significantly
after 3 yr of treatment; compared with controls the predicted adult height
gain was 8.0 cm in girls and 10.4 cm in boys. Furthermore, the ratio
between sitting height/height SD score decreased significantly in treated
children, whereas body mass index was not influenced by treatment. Puberty
was effectively arrested in the treated children, as was confirmed by
physical examination and prepubertal testosterone and estradiol levels.
GH-dependent hormones including serum insulin-like growth factor I and II,
carboxy terminal propeptide of type I collagen, amino terminal propeptide
of type III collagen, alkaline phosphatase, and osteocalcin were not
different between treated children and controls during the study period.
Thus, a GH dose of 4 IU/m(2) seems adequate for stabilization of the GH
reserve and growth in these GnRHa-treated children. We conclude that 3 yr
treatment with GnRHa was effective in suppressing pubertal development and
skeletal maturation, whereas the addition of GH preserved growth velocity
during treatment. This resulted in a considerable gain in predicted adult
height, without demonstrable side effects. Final height results will
provide the definite answer on the effectiveness of this combined
treatment
Phenotypic characterization of patients with deletions in the 3’-flanking SHOX region
Context. Leri–Weill dyschondrosteosis is a clinically variable skeletal dysplasia, caused by SHOX deletion or mutations, or a deletion of enhancer sequences in the 3’-flanking region. Recently, a 47.5 kb recurrent PAR1 deletion downstream of SHOX was reported, but its frequency and clinical importance are still unknown.Objective. This study aims to compare the clinical features of different sizes of deletions in the 3’-flanking SHOX region in order to determine the relevance of the regulatory sequences in this region.Design. We collected DNA from 28 families with deletions in the 3’-PAR1 region. Clinical data were available from 23 index patients and 21 relatives.Results. In 9 families (20 individuals) a large deletion ( ∼ 200–900 kb) was found and in 19 families (35 individuals) a small deletion was demonstrated, equal to the recently described 47.5 kb PAR1 deletion. Median height SDS, sitting height/height ratio SDS and the presence of Madelung deformity in patients with the 47.5 kb deletion were not significantly different from patients with larger deletions. The index patients had a median height SDS which was slightly lower than in their affected family members (p = 0.08). No significant differences were observed between male and female patients.Conclusions. The phenotype of patients with deletions in the 3’-PAR1 region is remarkably variable. Height, sitting height/height ratio and the presence of Madelung deformity were not significantly different between patients with the 47.5 kb recurrent PAR1 deletion and those with larger deletions, suggesting that this enhancer plays an important role in SHOX expression
Novel Leptin Receptor Mutations Identified in Two Girls with Severe Obesity Are Associated with Increased Bone Mineral Density
Background: Recessive mutations in the leptin receptor (LEPR) are a rare cause of hyperphagia and severe early-onset obesity. To date, the phenotype has only been described in 25 obese children, some of whom also had altered immune function, hypogonadotropic hypogonadism, reduced growth hormone secretion, hypothalamic hypothyroidism or reduced adult height. We provide a detailed description of the phenotype of 2 affected girls to add to this knowledge. Methods: Whole-exome sequencing and targeted sequencing were used to detect the LEPR mutations. RNA analysis was performed to assess the effect of splice-site mutations. Results: In 2 unrelated girls with severe obesity, three novel LEPR mutations were detected. Longitudinal growth data show normal childhood growth, and in the older girl, a normal adult height despite hypogonadotropic hypogonadism and the lack of an obvious pubertal growth spurt. Bone age is remarkably advanced in the younger (prepubertal) girl, and bone mineral density (BMD) is high in both girls, which might be directly or indirectly related to leptin resistance. Conclusion: The spectrum of clinical features of LEPR deficiency may be expanded with increased BMD. Future observations in LEPR-deficient subjects should help further unravel the role of leptin in human bone biology
Variable loss of functional activities of androgen receptor mutants in patients with androgen insensitivity syndrome
Androgen receptor (AR) mutations in androgen insensitivity syndrome (AIS) are associated with a variety of clinical phenotypes. The aim of the present study was to compare the molecular properties and potential pathogenic nature of 8 novel and 3 recurrent AR variants with a broad variety of functional assays. Eleven AR variants (p.Cys177Gly, p.Arg609Met, p.Asp691del, p.Leu701Phe, p.Leu723Phe, p.Ser741Tyr, p.Ala766Ser, p.Arg775Leu, p.Phe814Cys, p.Lys913X, p.Ile915Thr) were analyzed for hormone binding, transcriptional activation, cofactor binding, translocation to the nucleus, nuclear dynamics, and structural conformation. Ligand-binding domain variants with low to intermediate transcriptional activation displayed aberrant Kd values for hormone binding and decreased nuclear translocation. Transcriptional activation data, FxxFF-like peptide binding and DNA binding correlated well for all variants, except for p.Arg609Met, p.Leu723Phe and p.Arg775Leu, which displayed a relatively higher peptide binding activity. Variants p.Cys177Gly, p.Asp691del, p.Ala766Ser, p.Phe814Cys, and p.Ile915Thr had intermediate or wild type values in all assays and showed a predominantly nuclear localization in living cells. All transcriptionally inactive variants (p.Arg609Met, p.Leu701Phe, p.Ser741Tyr, p.Arg775Leu, p.Lys913X) were unable to bind to DNA and were associated with complete AIS. Three variants (p.Asp691del, p.Arg775Leu, p.Ile915Thr) still displayed significant functional activities in in vitro assays, although the clinical phenotype was associated with complete AIS. The data show that molecular phenotyping based on 5 different functional assays matched in most (70%) but not all cases. Copyrigh
Referral patterns of children with poor growth in primary health care
Background. To promote early diagnosis and treatment of short stature, consensus meetings were held in the mid nineteen nineties in the Netherlands and the UK. This resulted in guidelines for referral. In this study we evaluate the referral pattern of short stature in primary health care using these guidelines, comparing it with cut-off values mentioned by the WHO. Methods. Three sets of referral rules were tested on the
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