Hormonal profile of puberty in South Australian children II

Serum follicle stimulating hormone (FSH), luteinising hormone (LH) and oestradiol (E₂) concentrations in 117 girls aged 8 to 17.9 years were related to chronological age (CA), bone age (BA), breast development (B1–5+) and pubic hair development (PH1–5+). A progressive rise in serum LH and E₂ was noted in relation to CA, BA and pubertal development. Serum FSH levels reached a peak in mid-puberty and fell thereafter. The FSH/LH ratio decreased with advancing CA and BA. In comparing the data in girls (Part II) with that in boys (Part I) serum FSH and LH levels began to rise earlier in girls and were generally higher than levels seen in boys throughout puberty. Similarly, an earlier rise in serum E₂ in girls compared with T in boys supported the concept of an earlier activation of the female gonad.     

A profile of respiratory symptoms in urban and rural South Australian school children

This report describes the cross-sectional analyses of data from the first year of a longitudinal study using questionnaire and respiratory function data over a 5 year period from a sample of rural South Australian school children. The cumulative or lifetime prevalences of respiratory symptoms were estimated in 825 rural and 1261 urban school children aged between 5 and 15 years in order to determine if the prevalence rates differed between rural and urban school children. The study found the overall cumulative prevalence of asthma and/or wheezy breathing (AWB) to be 24.1% in the rural school children compared to 27.6% in the urban school children. Most children developed AWB symptoms before the age of 7 years, with 20% reporting moderately severe symptoms and 10% having more than one attack per fortnight. The cumulative prevalence of bronchitis, loose/rattly cough (BLRC) differed significantly between the rural school children (34.1%) and urban school children (47.9%). The BLRC symptoms preceded the development of AWB in many cases. Urban school children also reported a higher prevalence of atopic conditions.     

Hormonal changes during GnRH analogue therapy in children with central precocious puberty

Gonadotropin releasing hormone analogues (GnRHa) have been used for treatment of central precocious puberty (CPP) for more than 15 years. They are generally considered safe although data on potential long-term side effects are scarce. However, GnRHa therapy has profound effects on both the hypothalamopituitary-gonadal axis as well as on growth hormone (GH) secretion. Gonadal activity is increased in children with CPP; during GnRHa therapy secretion of gonadal hormones is suppressed as reflected by measurements of LH, FSH, and estradiol/testosterone. More recently, studies of levels of inhibin A and B as well as markers of androgen action such as SHBG and prostate specific antigen have demonstrated marked suppression of gonadal function possibly to infra-physiological levels. The possible long-term consequences of these observations have yet to be determined. Detailed analyses of the GH-IGF-I axis have revealed a decrease in levels of free, biologically active IGF-I during GnRHa treatment. These findings are in accord with the observed decrease in height velocity in children with CPP under treatment with GnRHa, and may also play a role in the relatively small gain in final height in most patients.     

Endocrinology in preadolescents and adolescents. I. Hormonal changes during normal puberty.

Hormonal changes during puberty have been well described: rise of gonadotropins followed by the rise of gonadal secretions at ages 10 to 16 years. The most striking new data are in fact concerning events that occur before puberty, first during the first months of life, second at age 7 years. The first event consists of a rise of gonadal steroids, which gives a hormonal impring that might be important for the future of the child. The second event concerns the prepubertal maturation of the androgenic zone of the adrenal cortex and the increasing secretion with age of the adrenal androgens. The mechanism of onset of both events is poorly explained. What causes the rise of gonadal steroids during infancy is unknown. Which pituitary factor, in addition to ACTH, stimulates the corticoadrenal androgenic zone, and which mechanism regulates its secretion remain unknown.     

The prevalence of respiratory symptoms in South Australian preschool children. I. Geographic location

Objectives: This study was designed to ascertain the prevalence of respiratory symptoms in South Australian preschool children and to investigate the relationship between prevalence rates and geographic location.
Methodology: Data were collected from 14124 families with a child aged 4 years 3 months to 5 years of age. This sample represents 73% of the State preschool population of that age. At the time of a routine preschool health check, parents completed a questionnaire regarding their child's respiratory health and place of residence (postcode).
Results: Results showed that the prevalence rates were as follows: (i) ever having chest wheezing 38.6%; (ii) chest wheezing within the preceding 12 months 25.2%; (iii) ever having asthma 22.5%; (iv) ever having a dry cough at night 33.7%; (v) ever having bronchitis or cough with sputum 55.3%; (vi) ever having hay fever 29.7%; (vii) prone to excessive head colds 32.6%; and (viii) ever having eczema 18.8%. Over 38% of parents claimed that winter was the season for the most frequent or severe attacks of wheezing and 31.7% claimed no seasonal difference. Winter was the season most associated with episodes of bronchitis (50.9%), with no seasonal difference in episodes for 29.8% of children. Prevalence rates differed by geographic location within South Australia and within the Adelaide metropolitan region.
Conclusion: This population-based survey shows that over 22% of South Australian 4 to 5 year old preschool children have had (or continue to have) asthma. The study also documented the geographic distribution of respiratory symptom prevalence within South Australia.     

Parent reported allergy and anaphylaxis in 4173 South Australian children

OBJECTIVES: To determine the prevalence of parent reported allergy and anaphylaxis in a sample of children and to investigate the first aid management of anaphylaxis in the schools and preschools that these children attend. METHODS: The study sample comprised 4173 South Australian children aged 3-17 years. Information was collected regarding parent-reported allergy and anaphylaxis. All children with known anaphylaxis were contacted and an attempt was made to contact those with reports of allergy to ascertain if these children had anaphylaxis. A telephone questionnaire was used to verify reports of anaphylaxis and determine the cause, severity and school first aid management of anaphylaxis. RESULTS: The rate of parent reported allergy and anaphylaxis was 7.3 and 0.59 per 100 children, respectively. Two-thirds of children with anaphylaxis did not have emergency medication available at school, an emergency action plan, or a teacher on site able to administer adrenaline for first aid use. CONCLUSIONS: Children attending preschool or school may have had a past history of anaphylaxis. Arrangements for first aid management of these children while in this environment are often inadequate.     

Precocious puberty: clinical and endocrine profile and factors indicating neurogenic precocity in Indian children

The objective of this study was to evaluate the clinical and endocrine profile of patients with precocious puberty followed up in a tertiary care hospital. Records of 140 patients (114 girls, 26 boys) with precocious puberty were reviewed. Clinical features including age of onset, stage of pubertal development, presenting symptoms, features suggestive of CNS involvement and family history were analyzed. Endocrine investigations included basal and GnRH-stimulated levels of LH and FSH as well as 17OHP, DHEA, hCG and thyroid profile. Abdominal and pelvic ultrasonography and CNS imaging were correlated with clinical features. Girls outnumbered boys in this series (4.4:1). Neurogenic central isosexual precocious puberty (CIPP) was more common in boys (10 out of 18, 55.6%) than girls (16 out of 77, 20.8%). The most common cause of neurogenic CIPP was hypothalamic hamartoma present in five girls and four boys. Other causes of neurogenic CIPP included neurotuberculosis, pituitary adenoma, hydrocephalus, post radiotherapy, CNS tumors and malformations. Peripheral precocious puberty (PPP) was secondary to adrenal causes in boys and ovarian cysts in girls. Benign variants of precocious puberty, such as premature thelarche and premature adrenarche, were present in 23 and six girls, respectively. Hypothyroidism was present in four girls and McCune-Albright syndrome in one girl. Girls with neurogenic CIPP had a lower age of onset as compared to idiopathic CIPP (3.6 +/- 2.7 years vs 5.4 +/- 2.5 years, p = 0.014). The lowest age of onset was seen in girls with hypothalamic hamartoma (1.6 +/- 0.9 years). Forty-seven girls with CIPP (seven neurogenic and 40 idiopathic) presented after the age of 6 years. Features of CNS involvement, in the form of seizures, mental retardation, raised intracranial tension or focal neurological deficits, were present in seven girls (43.8%) and four boys (40%), and gelastic seizures were present in three children. Girls with CIPP had greater bone age advancement (3.4 +/- 1.5 years) and negative height standard deviation for bone age (-2.7 +/- 1.5) than those with PPP (1.9 +/- 1.6 years and -1.3 +/- 1.3) and premature thelarche (0.4 +/- 0.4 years and -0.8 +/- 0.8). Patients with neurogenic CIPP had significantly higher levels of baseline and GnRH-stimulated levels of LH and FSH and LH:FSH ratio than those with idiopathic CIPP. Occurrence of neurogenic CIPP in seven girls with an age of onset after 6 years emphasizes the need for CNS imaging in these girls contrary to the current recommendations. The fact that 65.6% cases of idiopathic CIPP presented after the age of 6 years raises the possibility that these patients may be physiological variants of normal puberty. Pointers to neurogenic CIPP included early age of onset in girls, clinical features of CNS involvement, and elevated basal and stimulated LH levels and LH:FSH ratio.     

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.     

Serum fructosamine and lipid profile in type I diabetic children in Turkey

Serum levels of total cholesterol (TC), triglycerides (TG), lipoprotein cholesterol fractions (HDL-C and LDL-C) and fructosamine (FA) were determined in twenty-three children with Type I diabetes and twenty healthy children aged 4-14 years. Mean serum TC and HDL-C did not differ significantly between diabetic and nondiabetic children. Mean serum TG and FA showed a statistically significant increase in the diabetic group compared to healthy children. It is interesting to note that extremely high FA values had never been reported in the literature before were obtained for the Turkish diabetic children. Although we have observed relatively higher values for LDL-C/HLD-C ratio in diabetics, the difference between two groups was not statistically significant.     

Gonadotropin excretion during puberty in malnourished children

p6nadotropins were measured by radioimmunoassay of urine samples from 285 privileged Nairobi adolescents and from 238 rural peripubertal Kenyan boys and girls who had had moderate malnutrition during childhood. Gonadotropins were reduced at all ages in the rural adolescents, but pubertal stage-matched comparisons showed no differences between children of the two study areas in middle or late phases of sexual maturity. These results document the pattern of gonadotropin changes in an environment of reduced caloric intake and confirm the presumed hypothalamic-pituitary origin of the delayed adolescence that occurs under such circumstances.     

A health and nutritional profile of rural school children in KwaZulu-Natal, South Africa

A community-based cross-sectional study was undertaken to measure anthropometric indices, micronutrient status and prevalence of parasite infections in 579 rural South African primary school children. Eleven schools were selected randomly from a Magisterial District in southern KwaZulu-Natal (KZN). In each school, all pupils aged between 8 and 10 years were selected. The following outcome measures were obtained: anthropometric--height for age, weight for age and body mass index; micronutrient status--anaemia, serum ferritin and vitamin A; and prevalence of parasite infections--Ascaris lumbricoides, Trichuris trichiura and Schistosoma haematobium. The observed prevalences were: stunting 7.3%, underweight for age 0.7%, and obesity 3.1%; anaemia 16.5% (Hb < 12 g/dl), vitamin A deficiency 34.7% (serum retinol < 20 micrograms/dl) and 28.1% with reduced serum ferritin (< 12 ng/ml); Trichuris trichiura 53.9%, Ascaris lumbricoides 27.3% and Schistosoma haematobium 24.5%. We conclude that micronutrient deficiency, parasitic infestations and stunting remain significant problems among school-aged children in South Africa. Micronutrient supplementation and de-worming provide opportunities for school-based health promotion and primary health care interventions, and might produce significant health and educational benefits.     

Management of puberty in growth hormone deficient children

The pubertal growth spurt accounts for approximately one-eighth of adult height and is regulated by complex hormonal interactions involving the somatotropic and gonadal axes. The observation that children with growth hormone deficiency (GHD) may fail to achieve an appropriate pubertal growth spurt led to the development of strategies to optimize GH therapy during puberty. In one strategy the dosage of GH is increased during puberty to support pubertal growth and in keeping with the physiological increase in serum levels of the hormone seen at that age. A different approach is to combine a GnRH analog (GnRHa) to GH to stop pubertal development, delaying epiphyseal fusion and prolonging peripubertal growth. Both strategies require caution. As regards the first strategy, too high doses of GH may shorten the pubertal time for growth; we found a small, nonsignificant, improvement in final height by increasing the dose by less than half. Preliminary results on the second strategy are more encouraging. However, manipulation of puberty should be limited to selected patients who show a statural height SDS for bone age unfavorable in terms of height prognosis.     

Somatomedin-C in accelerated growth of children with precocious puberty

To assess the role of somatomedin-C as a possible mediator of the growth spurt in children with central precocious puberty, we compared Sm-C levels in 40 children with central precocious puberty, 87 age-matched normal children, and 110 normal pubertal controls. Somatomedin C levels were significantly elevated for age in the children with precocious puberty (P less than 0.01), and were similar to the levels observed during normal puberty. The patients with precocious puberty were given the luteinizing hormone releasing hormone analogue D-Trp6-Pro9-NEt-LHRH (LHRHa) for 6 months. Treatment caused a significant decrease in secondary sexual characteristics, growth rate, plasma gonadotropins, sex steroids (estradiol in the girls and testosterone in the boys), and Sm-C levels. Growth during LHRHa treatment returned to the age-appropriate rate, whereas plasma Sm-C levels, although lower than pretreatment levels, remained significantly elevated for age (P less than 0.002). In addition, growth rates before and during treatment did not correlate with the plasma somatomedin C levels, nor did the decreases in growth rate during LHRHa therapy correlate with the decreases in somatomedin C levels. Growth rates did correlate significantly, however, with plasma estradiol levels in the girls (P less than 0.0005) and with plasma testosterone levels in the boys (P less than 0.025). We conclude that the growth spurt in children with precocious puberty cannot be explained by the plasma level of somatomedin C.