Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Puberty, Delayed”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,513 records · Page 84Linked to original sources

Parathyroid function and bone metabolism in children with beta thalassaemia major: effects of sex steroid treatment.

OBJECTIVE: Data on parathyroid function in patients with homozygous beta-thalassaemia are discordant. Moreover, there is no report on the effects of sexual steroid treatment on bone metabolism in these patients. METHODS: Serum parathyroid hormone (PTH), calcitonin (CT) and osteocalcin (GLA protein) levels were measured in 121 patients. Thirty-three prepubertal subjects were treated for six months with sexual steroids. RESULTS AND CONCLUSIONS: Primary hypoparathyroidism was present in 3.3% of the patients. Osteocalcin levels were found to be lower in thalassaemic subjects than in controls, whereas CT values were similar. No effects of sexual steroid administration on plasmatic levels of osteocalcin were observed.

Adolescent↗

Maternal uniparental isodisomy of chromosome 14: association with autosomal recessive rod monochromacy.

Rod monochromacy (complete congenital achromatopsia) is inherited as an autosomal recessive trait of unknown genetic location. The disorder is characterized by total absence of color discrimination because retinal cone photoreceptors do not develop; systemic features do not occur. A 20-year-old white female with rod monochromacy presented with short stature (less than 5th percentile), mild developmental delay, premature puberty, small hands and feet (length less than 5th percentile), minimal dysmorphism, and a reproductive history of three consecutive first-trimester miscarriages. Cytogenetic analysis showed 45,XX,rob(14;14) in all 30 cells examined. Southern analysis of DNA from the patient and her phenotypically normal mother and two brothers (her father is deceased) ascertained the parental origin of the 14;14 Robertsonian translocation. Analysis of RFLPs associated with nine VNTR probes and two dinucleotide repeat polymorphisms from chromosome 14 demonstrated that the patient had inherited two copies of a single allele, each of which was maternally derived. A fully informative RFLP analysis of three probes from chromosome 14 enabled reconstruction of the paternal haplotype and showed the lack of any paternal contribution to the subject. These data are consistent with maternal isodisomy for all portions of chromosome 14 tested by these markers. This finding suggests that rod monochromacy maps to chromosome 14, and it emphasizes the importance of uniparental isodisomy to provide a putative chromosomal assignment of a gene for a rare autosomal recessive disorder.

Chromosome Mapping↗

Dynamic testing in the evaluation of male gonadal function.

The maturation and physiologic functions of male sexual apparatus are under the control of the hypothalamic-pituitary-gonadal (HPG) axis. The determination of gonadotropins and testosterone as secretory products of pituitary and gonads, respectively, represents the first step in the evaluation of male sexual function and the diagnosis of disorders in male reproductive axis. However, there are several clinical situations that require a dynamic evaluation of this system and the measurement of basal gonadotropins and testosterone must be combined with specific dynamic tests. These mainly consist in GnRH stimulation, which evaluates the endocrine reserve capacity of the pituitary, and human chorionic gonadotropin (hCG) stimulation, which is used in the assessment of Leydig cells activity. The paper illustrates the technical aspects, the normal/pathological responses and the role of these two tests in assessing the male HPG axis in respect to different clinical diagnostic queries.

Adolescent↗

The somatotropic axis in puberty.

Sex steroids markedly affect GH pulsatility by altering GH pulse amplitude without affecting GH pulse frequency. The type of sex steroid (testosterone or estrogen) appears to determine the timing of the pubertal growth spurt although both steroids appear to influence the amount of GH released from the pituitary. GH levels also affect gonadal secretion of sex steroids. The effects of the two are synergistic, but there is a real therapeutic dilemma of what to increase and when in children who are deficient in either GH or gonadotrophin secretion. Augmented GH pulsatility, particularly during the day, may alter markedly the interpretation of standard endocrine tests. Finally, the insulin resistance arising from an increased circulating concentration of GH may have important implications for the management of insulin-dependent diabetes during puberty.

Child↗

Primary empty sella syndrome and hypogonadotropic hypogonadism in young male patients.

Twelve male patients with absence of pubertal development and hypogonadotropic hypogonadism underwent a contrast-enhanced computed tomography of the sellar region and dynamic endocrine testing consisting of insulin-induced hypoglycemia, GnRH and TRH test. In two patients, clinically indistinguishable from the others, the presence of an empty sella turcica was demonstrated. They also showed, in comparison with patients with normal sellar morphology, an absent prolactin response to hypoglycemia with otherwise normal pituitary function. Empty sella, either due to congenital incompetence of the diaphragma sellae or to pituitary shrinkage due to regressive changes by hemorrhage, infarction and possibly autoimmune phenomena, may rarely be associated with hypogonadotropic hypogonadism.

Adolescent↗

Induction of puberty in hypogonadal children.

Puberty is the transitional period between childhood and adulthood when physical, sexual, and psychosocial maturation occurs. The onset of puberty is controlled by the gonadotropin-releasing hormone (GnRH) neuron and is triggered when inhibition of the neuron is lifted. Subsequently, GnRH induces secretion of other hormones, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which in turn stimulate the gonads. Concurrently, increases in estrogen levels in both boys and girls stimulate growth hormone (GH) and insulin-like growth factor-I (IGF-I) secretion, which are responsible for the pubertal growth spurt. In hypogonadal children, however, hypothalamic/pituitary defects or gonadal diseases preclude the production of these hormones, preventing the onset of puberty. Hormone replacement therapy with either estrogen or testosterone is a viable treatment option for hypogonadal children. These should be administered with consideration of sexual maturation rates, statural and bone growth rates, and occurrence of adverse effects. The merits and disadvantages of various hormone replacement therapies for girls and for boys are discussed.

Adolescent↗

Prevention and treatment of osteoporosis in chronically ill children.

Osteoporosis secondary to chronic disease in children has emerged as a major health issue. As the severity of a child's illness increases, so too does the number of factors affecting their bone health. Determinants of bone health in children include level of mobility, exposure to osteotoxic medication, nutritional status, calcium and vitamin D intake, chronic inflammation and pubertal development.

Adolescent↗

[The genetics of hypogonadotropic hypogonadism in the male].

Underlying causes of hypogonadotropic hypogonadism are acquired or congenital disorders of the hypothalamus or pituitary (e.g. pituitary adenoma, craniopharyngioma, prior radiotherapy, trauma, severe general diseases, extreme stress, genetic mutations). In addition to a comprehensive history and physical examination, the diagnostic work-up includes measurement of testosterone, LH and FSH, with the aim of differentiating between primary and secondary hypogonadism. Where indicated, investigation of pituitary function, the use of imaging procedures, possibly an olfactory test, a GnRH stimulation test or genetic analyses may be added. Depending upon the indication, treatment is effected with testosterone, GnRH or gonadotropines.

Adolescent↗

Multiple pituitary hormone deficiency (MPHD) associated with normal height, absent puberty and obesity.

We present a 22-year old girl with MPHD and a normal pituitary imaging (MRI) who grew to normal size without GH. She was very obese. At age 19 years replacement therapy with hydrocortisone, L-thyroxine and sex steroids was started. Despite severe growth hormone deficiency according to the provocative tests and decreased IGF I level our patient grew normally. On follow up at age 22 she is 174cm tall.

Adult↗

Prevalence of endocrine complications and short stature in patients with thalassaemia major: a multicenter study by the Thalassaemia International Federation (TIF).

Although numerous studies are available in the literature on endocrine complications in thalassaemia, little is known about this subject in developing countries. Therefore, an international multicenter study was conducted in a large series of children and adolescents with beta thalassaemia major in order to obtain more information on the prevalence of short stature and endocrine complications in different areas of the world and to elucidate the problems that must be dealt with in the future. A questionnaire was sent to 29 Centres treating a total of 3817 beta thalassaemia major patients. Thirty-six per cent of patients were over the age of 16 years. Short stature was present in 31.1% of males and 30.5% of females, and the prevalence of growth hormone deficiency was 7.9% in males and 8.8% in females. Lack of pubertal changes was the most common endocrine complication (40.5%) followed by hypoparathyroidism (6.9%), impaired glucose tolerance (6.5%), insulin-dependent diabetes mellitus (3.2%) and primary hypothyroidism (3.2%). The prevalence of endocrine complications differed among centres, particularly for growth hormone deficiency, hypoparathyroidism and hypothyroidism. Compliance to chelation therapy was poor in 51% of patients and serum liver enzymes were high in 65% of patients. Since several endocrine glands may be affected in patients with thalassaemia major, and their life expectancy is now much longer, it is important that physicians be aware of the endocrine abnormalities that may develop. Therefore, periodic evaluation of these problems should be carried out in thalassaemic patients with iron overload, particularly after the age of 11 years. In conclusion, since iron overload and liver damage seem to be the most important factors responsible for endocrine complications, adequate compliance to chelation therapy and rigid precautions against liver infections are imperative.

Adolescent↗

Effect of early thermal experience on pituitary-gonadal axis in female rats.

The reproductive system fully develops during postnatal stages of life, and as such it may be susceptible to environmental cues such as high temperature. Thus, the purpose of the study was to compare how exposure to 34 degrees Celsius ambient temperature affects pituitary-gonadal axis of immature and adult female rats. Three groups of females at proestrous or metaestrous (n=38) were used in the study. The females were housed in ambient temperature of 34 degrees Celsius (WR group, n=10) or room temperature (CR group, n=16) from birth to adulthood. The females from the third group were acclimated to 34 degrees Celsius as adults (WA group, n=12). In the WR group the onset of puberty was delayed in comparison to the CR group. The plasma PRL level was lower during proestrous and higher during metaestrous in the WR group compared to the CR group. During metaestrous, lower FSH and higher progesterone (P(4)) plasma concentrations were found in the WR females. No changes in LH and oestradiol (E(2)) plasma concentrations were demonstrated. Higher in vitro E(2) and lower P(4) secretions under FSH stimulation were observed in the WR follicles compared to those of the CR group. The WR group also demonstrated higher basal and LH-stimulated luteal in vitro secretion of P(4) than controls. Plasma LH and FSH concentrations during metaestrous were higher in WA females than in the WR group, but PRL level was lower. Follicles of the WA group were unresponsive to FSH with respect to steroid secretion. In addition, LH stimulated luteal E(2) secretion in this group. P(4) release by luteal cells was lower in the WA than in the WR group. We concluded that WR females differ from WA in reproductive system adjustments to rearing temperature and that early thermal experience is more effective in antagonizing the effect of high temperature than acclimation of adult females.

Animals↗

Prevalence of growth and puberty failure with respect to growth hormone and gonadotropins secretion in beta-thalassemia major.

BACKGROUND: Present transfusion protocols have increased the life expectancy of patients with beta-thalassemia major, but siderosis is a major clinical complication of the treatment. Short stature and hypogonadism are extremely frequent in patients with thalassemia. To investigate the influence of age at the onset of blood transfusion, iron chelation therapy, and serum ferritin levels on growth and pubertal development in thalassemic patients, and the prevalence of these endocrine complications with respect to pituitary somatotropic and gonadotropic functions, this study was designed. METHODS: Clinical data of 158 patients (82 females and 76 males) with thalassemia major, aged 10 - 20 years (mean age: 15.1 +/- 4.8 years) were collected from a pediatric hematology clinic in Tehran. Height was measured and stages of puberty were determined by a pediatric endocrinologist. Serum ferritin concentration, liver function tests, serum calcium and phosphorus, blood sugar, free thyroxine (FT4), TSH, FSH, LH, dehydroepiandrosterone sulfate, testosterone (in boys), estradiol (in girls), and insulin-like growth factor I were measured after overnight fasting. In patients with a height more than 2 standard deviation below the mean, the growth hormone stimulation test was considered. Bone age was determined in all patients. RESULTS: Thalassemic patients in this study showed a high prevalence of short stature (62%) and hypogonadism (69%). We found a low serum level of gonadotropins (FSH and LH) in over 14-year-old patients with impaired puberty, which indicated that hypogonadotropic hypogonadism is responsible for this complication. Results of growth hormone provocative tests and serum insulin-like growth factor I levels in short stature patients showed a reduced growth hormone response in 38% and low insulin-like growth factor I levels in 42% of thalassemic patients. Short stature and hypogonadism were more common in patients with serum ferritin levels above 2000 microg/L and these complications were significantly more frequent in patients who started treatment later than that of the patients who started treatment in the first years of life (P < 0.001). CONCLUSION: Short stature and hypogonadism are extremely frequent in our patients with thalassemia, but correct blood transfusion and appropriate iron chelation therapy can prevent or limit these complications. These data support the need for vigilant follow-up of patients with thalassemia in order to treat endocrine dysfunction at an appropriate age.

Adolescent↗