Quality of life after growth hormone therapy and induced puberty in women with Turner syndrome

OBJECTIVE

To evaluate health-related quality of life (HRQoL) in young women with Turner syndrome (TS) after long-term growth hormone (GH) therapy and induced puberty and to analyze whether HRQoL was influenced by auxologic parameters, pubertal development, or subjective parameters.

STUDY DESIGN

The study group comprised 49 women with TS, mean (standard deviation) age 19.6 (+/-3.0) years, all former participants of 2 GH studies, > or =6 months after GH discontinuation. Puberty was induced by estrogen treatment, at mean age 12.9 (+/-1.1) years. HRQoL was measured by self-reports of the 2 generic questionnaires, SF36 and TAAQOL. As an additional source of information on HRQoL, we applied parental proxy reports.

RESULTS

HRQoL of the women with TS was normal. Remarkably, the women with TS had higher HRQoL scores on some of the scales, including "social functioning" and "role-emotional." Satisfaction with height and breast development had a positive influence on several HRQoL scales.

CONCLUSIONS

The young women with TS who reached normal height and had age-appropriate pubertal development reported normal HRQoL. The relatively high scores on some of the HRQoL scales can be explained by an estrogen effect or by a possible response shift, indicating a different internal reference in women with TS. We hypothesize that GH and estrogen treatment positively influenced HRQoL in young women with TS.

Low Bone Mineral Density in Adolescents with β-Thalassemia

The pervasiveness of low bone mass (LBM) in beta-thalassemia (Thal) patients (pts) is escalating as the average life expectancy of these pts increases. Adolescence is a period of substantial bone accrual, which is crucial for future bone strength. Studies of LBM are prevalent among adults with Thal. However, limited information exists about bone accrual and LBM in adolescents with the disease. Thirty-one pts with beta-Thal (26 Thal major [TM], 5 Thal intermedia [TI]), aged 9-20 years (mean: 15.3 years), 14 males and 17 females, underwent measurement of spinal bone mineral density (BMD) by DEXA (Lunar, Prodigy). Height, weight, body mass index, and Tanner stage were assessed at the time of the BMD measurement. A total of 16.1% of the patients had normal bone mass (Z > or = -1), 22.6% had reduced bone mass (Z = -1 to -2), and 61.3% had low bone mass (Z < or = -2). BMD Z correlated with height and weight Z scores. Some 53.9% of subjects had normal gonadal function and 46.1% had induced puberty with gonadal steroids. BMD Z significantly worsened with age (P < .0001). However, there was no difference in the LBM prevalence between subjects with normal versus those with induced puberty: BMD Z was -2 or less in 71.4% of subjects with normal puberty versus 66.7% in those with induced puberty. Our results indicate a high prevalence of LBM among adolescents with Thal regardless of adequate transfusion and chelation regimens. Bone accrual was found to be suboptimal in adolescents with normal or induced puberty. Thus, calcium and vitamin D supplementation with antiresorptive therapies should be evaluated in the adolescent Thal pt with close monitoring of growth and sexual development.

Longitudinal monitoring of bone accretion measured by quantitative multi-site ultrasound (QUS) of bones in patients with delayed puberty (a pilot study)

OBJECTIVE

to compare the effect of anabolic agents on bone accretion in boys with constitutional delay of puberty (CGDP).

RATIONALE

it has been suggested that an appropriate timing of puberty is necessary for normal bone mineral density (BMD) acquisition. Proper bone development during childhood is the key factor in achieving higher peak bone mass during middle age, which may not be achievable in CGDP children, and thereby osteoporosis may appear at an earlier age then expected.

PATIENTS AND METHODS

45 boys with CGDP aged 14-16 years were monitored longitudinally, every 3 months over 12 months with Sunlight Omnisense, a quantitative ultrasound device (Tel Aviv, Israel). The apparatus is a multi-site bone sonometer that obtains axial Speed of Sound (SOS). Based on a reference database obtained on n=1,085 (490 boys) 0-18 years, a normative curve was determined. Fifteen (14-16 years old) of the CGDP patients were treated with I.M. testovirone depot 100 mg monthly for 6 months, 15 (14-16 years old) were treated with oxandrolone 5 mg/m(2) daily for 6 months, and 15 (14-16 years old) were in an observation group.

RESULTS

whereas the quantitative ultrasound (QUS) Z-score had shown some increase over time in CGDP-treated patients, an increase was found in tibia Z-score from -0.5(-0.64, -0.36) to -0.4(-0.54, -0.26) and from -0.52(-0.67, -0.38) to -0.31(-0.44, -0.11) in the testosterone and oxandrolone-treated groups, respectively, [median (25%, 75%)]. An increase in radius Z-score from -0.52(-0.65, -0.25) to -0.4(-0.54, -0.15) and from -0.51(-0.61, -0.21) to -0.37(-0.47, -0.07) in the testosterone- and oxandrolone-treated groups respectively [median (25%,75%)]. Z-score SOS decreased in the observation group -0.5(-0.66, -0.3) to -0.69(-0.85, -0.54) and -0.5(-0.59, -0.41) to -0.81(-0.95, -0.55) in tibia (P = 0.032) and radius (P = 0.029), respectively. Despite the fact that QUS remained in the normative range in all patients, a clear deterioration was demonstrated in untreated CGDP patients.

CONCLUSION

longitudinal follow-up of patients with CGDP may detect an early pattern of deterioration of bone mass.

Regulation and disorders of pubertal timing

Disorders of pubertal timing are common and challenging problems for pediatric endocrinologists. Early or late puberty can have immediate effects on a child's psychosocial well-being and may have long-term effects on adult stature. Much is known about the regulation of the hypothalamic-pituitary-gonadal axis, but the triggers of pubertal onset in the general population remain elusive. This article reviews recent data suggesting a possible shift in the age of pubertal onset; current knowledge regarding factors that regulate the onset of puberty; and the etiologies, diagnosis, and treatment of precocious and delayed puberty.

Reversible kallmann syndrome, delayed puberty, and isolated anosmia occurring in a single family with a mutation in the fibroblast growth factor receptor 1 gene

Kallmann syndrome (KS) is a clinically and genetically heterogeneous disorder. Recently, loss-of-function mutations in the fibroblast growth factor receptor 1 (FGFR1) gene have been shown to cause autosomal dominant KS. To date, the detailed reproductive phenotype of KS associated with mutations in the FGFR1 has yet to be described. We report a kindred comprising a male proband with KS and spontaneous reversibility, whose mother had delayed puberty and whose maternal grandfather isolated anosmia. The proband presented at age 18 yr with KS and was subsequently treated with testosterone (T) therapy. Upon discontinuation of T therapy, he recovered from his hypogonadotropic hypogonadism, as evidenced by a normal LH secretion pattern, sustained normal serum T levels, and active spermatogenesis. The three members of this single family harbor the same FGFR1 mutation (Arg(622)X) in the tyrosine kinase domain. This report demonstrates 1) the first genetic cause of the rare variant of reversible KS, 2) the reversal of hypogonadotropic hypogonadism in a proband carrying an FGFR1 mutation suggests a role of FGFR1 beyond embryonic GnRH neuron migration, and 3) a loss of function mutation in the FGFR1 gene causing delayed puberty.

Pubertal androgen therapy in boys

Anabolic-androgenic steroids (AAS) are necessary for normal male sexual differentiation and development and pubertal development. Androgen therapy is appropriate for boys with delayed development (constitutional delay of growth and puberty, CDGP) as well as those with primary or secondary hypogonadism. The principal goal is to restore the serum testosterone (T) level to the normal range at each stage of adolescent development and then to the normal adult range if the hypogonadism is permanent. In addition the levels of dihydrotestosterone and estradiol should also be within the normal range. One should be able to do that with a wide variety of androgen preparations-injectable, implantable, and cutaneous patches or gels. However, during the transition from prepubertal to adult it is difficult to reliably deliver the relatively small doses of T necessary for adolescent development using any of the cutaneous preparations. Androgen therapy should permit normal linear growth (including the adolescent growth spurt), adolescent sexual development, and the attainment of normal body composition including lean body mass, bone and the appropriate regional distribution of body fat as well as the psychological development appropriate for the stage of adolescent development.

Pubertal upregulation of erythropoiesis in boys is determined primarily by androgen

OBJECTIVES

To study the relative roles of androgens and the growth hormone-insulin-like growth factor I (GH-IGF-I) system in the regulation of erythropoiesis in boys during puberty.

STUDY DESIGN

We treated 23 boys with constitutional delay of puberty with low-dose testosterone (T), in combination with either a potent aromatase inhibitor, letrozole (Lz; 2.5 mg/d), or placebo (P). The study design was randomized, double-blinded, and placebo-controlled between the treated groups. Treatment with T + Lz was associated with high T and low IGF-I concentrations, whereas treatment with T + P resulted in moderately increased T and high IGF-I concentrations.

RESULTS

The blood hemoglobin concentration increased by 1.6 g/dL in T + Lz-treated boys, despite their low IGF-I concentrations. The estimated red blood cell volume increased more in T + Lz-treated than in T + P-treated boys (349 vs 174 mL, respectively, P = .01). Serum T concentrations during the treatment period correlated with the 12-month increments in hemoglobin and red blood cell volume. The changes in blood hemoglobin concentration and RBC in T + Lz-treated boys were similar to those we observed in a population of normal adolescent boys in the late stages of puberty.

CONCLUSIONS

The pubertal increase in hemoglobin concentration in boys is related to direct androgen effects.

Constitutional delay of growth and puberty: from presentation to final height

This retrospective study evaluated clinical characteristics of patients with constitutional delay of growth and puberty (CDGP) at presentation, during puberty and at final height. The records of 151 children (105 boys, 46 girls) with CDGP were reviewed and the results were evaluated with respect to findings in healthy Turkish schoolchildren. CDGP was twice as frequent in boys as in girls. Height and weight deficit and short sitting height of the children were evident at presentation and continued up to final height. Mean age of onset of puberty was retarded by 2.5 years in girls and by 3 years in boys. The time between onset of puberty and pubertal growth spurt was shorter in both girls and boys than in the controls. Peak growth velocity was compromised in both girls and boys. Forty-one patients (30 boys, 11 girls) reached final height (FH). Mean FH was shorter than both target height and predicted adult height. The Bayley-Pinneau method was found to be a better predictor of FH than either the Tanner-Whitehouse method or target height. FH also showed correlation with the father's height. There was no effect of testosterone treatment on final height. Height deficit at onset of puberty, shorter duration between onset of puberty and pubertal growth spurt, compromised peak growth velocity and short upper segment due to delayed puberty, are findings which may explain the decreased final height of children with CDGP.

Human chorionic gonadotropin therapy in adolescent boys with constitutional delayed puberty vs those with beta-thalassemia major

We studied 12 adolescent boys with beta-thalassemia major and delayed puberty (age, 15.8 +/- 1 years) with Tanner I sexual development treated with a long-term low-transfusion regimen. Ten nonthalassemic adolescents (> 14 years) with constitutional delay of growth and puberty (CDGP) served as controls. Auxologic parameters and testicular size were measured, and bone age was determined. Measurement of basal gonadotropin (luteinizing hormone [LH] and follicle-stimulating hormone [FSH]) and testosterone (T) levels taken at 8 am revealed prepubertal levels in both groups of patients. Human chorionic gonadotropin (hCG, 2500 U/m(2)) was injected intramuscularly twice weekly for 6 months, and anthropometric data, testicular diameter, and serum T concentrations were remeasured after 1 and 6 months. The testicular diameter after 6 month of hCG therapy was significantly correlated with the testicular diameter and T level after 1 month of therapy (r = 0.93 and 0.39, respectively, P < .01). After 6 months of hCG therapy, the mean growth velocity (GV) increased from 4.1 to 8.6 cm/y in thalassemic patients and from 4.6 to 10.3 cm/y in those with CDGP during hCG therapy. In thalassemic boys, the mean T concentration increased from 0.93 to 2.7 nmol/L (mean increase = 1.8 nmol/L) vs an increase from 0.47 to 4.81 nmol/L (mean increase = 4.32 nmol/L) in those with CDGP. All adolescents with CDGP, but only 7 the 12 thalassemic adolescents, had T secretion above 2 nmol/L after 6 months of hCG therapy and maintained their growth and pubertal development for a year after stopping hCG. The 5 thalassemic patients with defective T secretion after hCG therapy had significantly higher ferritin level (1985 +/- 658 ng/mL) vs the other 7 patients (1100 +/- 425 ng/mL). These findings denoted significant testicular dysfunction in those patients with higher iron overload (testicular siderosis). Statural GV was significantly correlated with insulin-like growth factor 1 (IGF-1) concentrations and testicular diameter after hCG therapy (r = 0.5 and 0.43 respectively, P < .001). In summary, hCG therapy was effective in treating 7 of 12 (58%) of thalassemic adolescents with delayed puberty. In the rest of patients (5/12, 46%) with significantly higher iron overload, hCG therapy failed to stimulate testicular growth and adequate T. Proper iron chelation appears to protect against testicular dysfunction. In the first group of patients, hCG therapy can be used for the treatment of their hypogonadism, whereas T replacement remains the therapy of choice for the second group.

Hypogonadism in a patient with a mutation in the luteinizing hormone beta-subunit gene

A 30-year-old man who presented with delayed puberty and infertility was found to have hypogonadism associated with an absence of circulating luteinizing hormone. The patient had a homozygous missense mutation in the gene that encodes the beta subunit of luteinizing hormone (Gly36Asp), a mutation that disrupted a vital cystine knot motif and abrogated the heterodimerization and secretion of luteinizing hormone. Treatment with human chorionic gonadotropin increased circulating testosterone, promoted virilization, and was associated with the appearance of normal spermatozoa in low concentrations. This case illustrates the important physiological role that luteinizing hormone plays in male sexual maturation and fertility.

Ascertainment and Treatment of Delayed Puberty

The majority of patients with pubertal delay, can be classified as having primary pubertal delay (constitutional delay of growth and puberty, CDGP), although any child with a chronic disease could present with delayed puberty. In contrast, children with hypogonadism, either hyper- or hypogonadotropic, exhibit a total absence of pubertal development. Hence, early evaluation of these patients should be performed. Delay of puberty leads to psychological problems, secondary to short stature and/or delay in the acquisition of secondary sex characteristics and the reduction of bone mass. Although the final height in patients with CDGP is usually normal, some of these patients do not reach the third percentile or remain in the lowest part of the growth chart according to familial height. The most common reason for treating CDGP patients, usually with sex steroids, is for psychological difficulties and for loss of bone mineralization. Treatment must be individualized. Therapeutic options and new drugs will be discussed. Appropriate treatment and adequate nutritional intake are indicated in patients with delayed puberty due to chronic illness. In patients with hypo- or hypergonadotropic hypogonadism, puberty must be induced or completed. Different treatments (GnRH analogues, gonadotropins and sex steroids), and the main objectives are discussed.

Application of gonadotropin releasing hormone in hypogonadotropic hypogonadism--diagnostic and therapeutic aspects

BACKGROUND

Puberty is the result of reactivation of the gonadotropin releasing hormone (GnRH) pulse generator resulting in an increasing release of GnRH by the hypothalamus, which stimulates the gonadotropic cells of the pituitary to synthesize and secrete LH and FSH. Hypogonadotropic hypogonadism (HH) is often the result of GnRH deficiency. The clinical picture is characterized by the absence of pubertal development and infertility. It is difficult to differentiate HH from delayed puberty since low gonadotropin and low testosterone levels are found in both conditions. We hypothesized that long-term GnRH administration may differentiate between the two conditions by a difference in the increase of gonadotropins, the idea being that in normal delayed puberty the pituitary of the patient has been primed with GnRH during the fetal and early postnatal period.

PATIENTS

Seventeen adolescents suspected of having hypogonadotropic hypogonadism were treated with pulsatile GnRH for 7 days. At the present time, the diagnosis of these patients is known and the results of the long-term GnRH stimulation have been evaluated according to the present diagnosis.

RESULTS

The results show that the increase in gonadotropins following GnRH treatment is similar in both conditions. Therefore, at a prepubertal age a normal delayed puberty cannot be distinguished from hypogonadotropic hypogonadism using long-term GnRH stimulation. Long-term pulsatile GnRH treatment is a physiological therapy for the induction of puberty. Unlike testosterone it has the advantage of stimulation of testicular growth and fertility, as well as virilization, in males. We have treated 68 male patients with HH with pulsatile GnRH. The results show testicular growth and virilization in all the patients and spermatogenesis in 58 patients. Wearing a portable pump is cumbersome. However, the patients were very motivated and adapted very easily to this inconvenience. When spermatogenesis had developed, GnRH treatment was changed to human chorionic gonadotropin (hCG) administration 1-2 times per week intramuscularly or subcutaneously. During hCG therapy spermatogenesis was maintained or even improved. At least ten patients fathered children.

CONCLUSION

Pulsatile GnRH cannot distinguish between a normal delayed puberty and a hypothalamic defect in still prepubertal patients. Pulsatile GnRH offers an appropriate way to initiate testicular growth including virilization and fertility in males with hypogonadotropic hypogonadism.

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.

Augmentation of growth hormone secretion after testosterone treatment in boys with constitutional delay of growth and adolescence: evidence against an increase in hypothalamic secretion of growth hormone-releasing hormone

The increase in pituitary GH secretion that occurs during mid-late puberty in boys follows an increase in circulating testosterone (T) concentration; the direct mechanism by which this occurs is unknown. We hypothesized that T increases GH secretion during puberty by augmenting hypothalamic output of GHRH. Using constant infusions of a GHRH antagonist, we tested this hypothesis in six early pubertal boys with constitutional delay of growth and adolescence who had a mean chronological age of 14.0 +/- 0.3 yr and mean bone age of 11.4 +/- 0.2 yr. Blood samples were obtained from subjects every 15 min for 24 h during the overnight infusion of normal saline (2000-0600 h) and again during the overnight infusion of GHRH antagonist (0.33 microg/kg/h) the following night. Subjects then received transdermal T (5-mg patch) for 12 h nightly and were studied again after 4 wk of treatment. Serum samples were assayed for GH and total ghrelin; the percent suppression of GH during GHRH antagonist infusion was calculated. Morning serum T rose from 0.44 +/- 0.09 to 4.43 +/- 0.74 microg/liter (P = 0.005). T treatment was associated with a 92.6% increase in mean nocturnal GH secretion area under the curve (830 +/- 177 to 1599 +/- 340 microg/24 h.liter). Infusion of GHRH-antagonist suppressed mean nocturnal GH area under the curve by 29.1% before T treatment (830 +/- 177 to 621 +/- 168 microg/24 h.liter), and by 29.4% after T treatment (1599 +/- 340 to 1182 +/- 249 microg/24 h.liter; P = 0.99). Somatotroph sensitivity to GHRH was tested with 0.1- and 1.0-microg/kg doses of GHRH-44 iv; GH response did not change with regard to T treatment. The mean 24-h concentration of total ghrelin was unchanged with regard to T treatment. In summary, nightly transdermal T administration in six boys with constitutional delay of growth and adolescence increased GH output almost 2-fold, whereas the degree of GH suppressibility by GHRH antagonist remained unchanged. We conclude that the T-associated augmentation of GH secretion during early puberty in boys is unlikely to involve an absolute increase in hypothalamic GHRH output.

Vitamin A and iron supplementation is as efficient as hormonal therapy in constitutionally delayed children

OBJECTIVE

To assess the effect of nutritional supplementation on growth and puberty in constitutionally delayed children.

PATIENTS

One hundred and two boys, 13.6-15.5 years of age, who were referred because of short stature and delayed puberty.

METHODS

The boys were randomly allocated to one of the following treatment groups: oxandrolone therapy, 5 mg/day for 6 months (n = 15), testosterone depot, 100 mg monthly for 3 months (n = 15) or for 6 months (n = 20), nutritional programme (n = 17), oxandrolone and nutritional programme (n = 15) or passive observation (n = 20). Boys in the nutritional programmes received 12 mg/day iron and 6000 IU/week of vitamin A. Outcome measurements were of height, weight, pubertal signs, dietary intake, serum vitamin A, iron, GH and IGF-1.

RESULTS

Six months of vitamin A supplementation induced growth acceleration similar to that seen in the oxandrolone- and testosterone-treated children, and significantly greater than in the observation group (9.3 +/- 2.9 vs. 4.0 +/- 0.9 crn/yr, P < 0.001). Whereas in the vitamin A-supplemented group, puberty (increase in testicular volume >/= 12 ml) was induced within 12 months. In all testosterone-treated patients, pubic hair was noted within 3 months and a testicular volume of >/= 12 ml was observed 9-12 months after the initiation of therapy. No pubertal signs were noted in the observation group during this time.

CONCLUSIONS

Subnormal vitamin A intake is one of the aetiological factors in delayed pubertal maturation. Supplementation of both vitamin A and iron to normal constitutionally delayed children with subnormal vitamin A intake is as efficacious as hormonal therapy in the induction of growth and puberty.

Serum androgen bioactivity in adolescence: a longitudinal study of boys with constitutional delay of puberty

We have examined the relationship between serum androgen bioactivity, as measured with a recombinant cell bioassay, and progression of puberty in 14 boys with constitutional delay of puberty. Six boys were followed up without treatment (control group), and eight boys received low-dose (1 mg/kg) testosterone enanthate im for 0-6 months together with an aromatase inhibitor, letrozole, 2.5 mg orally once a day for 0-12 months (treatment group). In the control group, serum androgen bioactivity increased during the course of puberty (P < 0.001). During 0-12 months of the study, the boys in the treatment group had higher androgen bioactivity levels (P < 0.05) and faster rate of pubic hair growth than the control boys (P < 0.05). Overall, the average serum androgen bioactivity during 12 months of follow-up correlated strongly with the concomitant changes in Tanner genital (r(S) = 0.89; n = 13; P < 0.005) and pubic hair stages (r(S) = 0.79; n = 13; P < 0.01). In conclusion, our results suggest that circulating androgen bioactivity mediates the tempo of pubertal maturation and that the combination of testosterone and letrozole given to boys with constitutional delay of puberty accelerates puberty.

Late or delayed induced or spontaneous puberty in girls with Turner syndrome treated with growth hormone does not affect final height

Although it has been well established that GH treatment increases final height (FH) in girls with Turner syndrome (TS), the optimal ages to start GH therapy and introduce estrogens for pubertal induction have not been defined. We evaluated retrospectively the influence of the age at onset of GH treatment and age at onset of puberty on FH of 186 adult TS women treated during childhood with GH. Puberty started spontaneously in 38 patients, and it was induced in 148 girls with ethinyl estradiol (mean +/- SD starting dose, 66 +/- 32 ng/kg.d). Patients with spontaneous or induced puberty were divided into quartiles on the basis of age at initiation of GH treatment (3-10, 10-12, 12-14, and 14-19 yr). FH was 151.7 +/- 6.0 cm; there were no FH differences between patients with induced or spontaneous puberty, nor were there differences between the age quartiles. Puberty started earlier in the girls with spontaneous puberty than in those with induced puberty (12.4 +/- 1.3 yr vs. 14.5 +/- 1.9 yr; P < 0.0001). The age at onset of puberty was not related to FH. Pubertal growth was 15.4 +/- 4.6 cm in the girls with spontaneous puberty and 8.6 +/- 4.3 cm in the girls with induced puberty (P < 0.0001). We conclude that GH treatment results in a significant increase in FH in most TS girls. Under the conditions of GH treatment and induction of puberty that we have used, the age at start of GH treatment was not related to FH; in addition, late or delayed induced or spontaneous puberty did not affect FH.

Novel treatment of short stature with aromatase inhibitors

Estrogens have an essential role in the regulation of bone maturation and importantly in the closure of growth plates in both sexes. This prospective, randomized, placebo-controlled study was undertaken to evaluate whether suppression of estrogen synthesis in pubertal boys delays bone maturation and ultimately results in increased adult height. A total of 23 boys with constitutional delay of puberty (CDP) received a conventional, low-dose testosterone treatment for inducing progression of puberty. Eleven of these 23 boys were randomized to receive a specific and potent P450-aromatase inhibitor, letrozole, for suppression of estrogen action, and 12 boys were randomized to receive placebo. Estradiol concentrations in the letrozole-treated boys remained at the pretreatment level during the administration of letrozole, whereas the concentrations increased during the treatment with testosterone alone and during spontaneous progression of puberty. Testosterone concentrations increased in all groups, but during the letrozole treatment, the increase was more than fivefold higher than in the group treated with testosterone alone. The inhibition of estrogen synthesis delayed bone maturation. The slower bone maturation in the boys treated with testosterone and letrozole, despite higher androgen concentrations, than in the boys treated with testosterone indicate that estrogens are more important than androgens in regulation of bone maturation in pubertal boys. During the 18 months follow-up, an increase of 5.1 cm in predicted adult height was observed in the boys who received testosterone and letrozole, but no change was seen in the boys who received testosterone alone or in the untreated boys. This finding indicates that an increase in adult height can be attained in growing adolescent boys by inhibiting of estrogen action.

Novel treatment of delayed male puberty with aromatase inhibitors

BACKGROUND

As the evidence for the role of oestrogens in epiphyseal closure appears unequivocal, we hypothesized that boys with constitutional delay of puberty would attain greater adult height if oestrogen action was suppressed.

METHODS

We conducted a randomized, double-blind, placebo-controlled study in which we treated boys with constitutional delay of puberty with testosterone plus placebo or testosterone plus a potent fourth-generation aromatase inhibitor, letrozole.

FINDINGS

Letrozole effectively inhibited oestrogen synthesis. The 17beta-oestradiol concentrations increased in the untreated group and in the testosterone/placebo-treated group, but in the testosterone/letrozole-treated group no such increase was observed until letrozole treatment was discontinued. Testosterone concentrations were threefold higher in the testosterone/letrozole-treated group than in the other groups. Within 18 months, bone age had advanced by 1.1 +/- 0.3 years in the untreated group and by 1.7 +/- 0.3 years in the testosterone/placebo-treated group, but only by 0.9 +/- 0.2 years in the testosterone/letrozole-treated group (p = 0.02 between treatment groups). Predicted adult height did not change significantly in the untreated group and in the testosterone/placebo-treated group, whereas in the testosterone/letrozole-treated group the increase was 5.1 +/- 1.2 cm (p = 0.004).

CONCLUSIONS

Our findings suggest that, if oestrogen action is inhibited in growing adolescents, adult height will increase. This observation provides a rationale for studies aimed at delaying bone maturation in several growth disorders.

Induction of puberty in the hypogonadal girl--practices and attitudes of pediatric endocrinologists in Europe

The management of children and adolescents with hypogonadism and in particular the induction of puberty in the hypogonadal girl is subject to controversy. Therefore, under the auspices and through organization of the Drugs and Therapeutics Committee of the European Society of Paediatric Endocrinology (ESPE), an interactive voting session and workshop was held at the 39th ESPE Annual Meeting in Brussels to discuss these topics. Common practice in Europe and attitudes of pediatric endocrinologists in Europe were questioned and recorded in the 1.5-hour program. We now report on some of the results of the questionnaires and discussions of that session to further the discussion on and knowledge of current concepts of induction of puberty in the hypogonadal girl in Europe. It became clear from the data accumulated here that the start of treatment, the aims of therapy and the modalities of how to treat the hypogonadal girl vary amongst pediatric endocrinologists in Europe. For example, a chronological age > or =11 years was considered appropriate for the start of estrogen therapy by 40.4% (out of 188 answers), while 47.8 and 7.5% felt that a chronological age > or =13 and > or =15 years respectively was appropriate. In respect to the form and route of estrogen administration, the audience was asked for their common estrogen replacement practice: 31.9% used oral 17beta-estradiol treatment, while 10% would prescribe 17beta-estradiol transdermal patches. Another 12.2% would recommend conjugated estrogens (e.g. Premarin) orally, 4.8% use oral estradiol valerate and 39.3% ethinylestradiol orally. Only 1.8% out of 229 physicians answering were undecided. In addition, counseling of patients and their families is quite variable and perceptions for example regarding potential pregnancies in affected women are also not uniform. In this report the authors do not want to provide their own personal views but rather reflect current practice in Europe. It is hoped that a more uniform picture will emerge once European and international guidelines on how to treat the girl with hypogonadism will be available and even more discussions amongst doctors from different countries have been led.

Physiological principles of endocrine replacement: estrogen

The major biologically active circulating estrogen in both males and females is estradiol (E(2)). Circulating E(2) is a product of the ovarian granulosa cell and the testicular Leydig cell. Its gonadal formation is dependent on A-ring aromatization of its immediate precursor, testosterone, by a particular isoform of the enzyme aromatase, which also catalyses the conversion of the much weaker androgen, androstenedione, to the weak estrogen, estrone. E(2) is also formed in non-gonadal tissues, such as adipose tissue, liver, muscle and brain. Only adipose tissue makes significant extra-gonadal contributions to circulating estrogen. Loss of ovarian function during reproductive life, as a result of loss of gonadotropin secretion (secondary hypogonadism) or as a result of premature ovarian failure (generally defined as cessation of ovarian function prior to age 40), results in loss of the majority of circulating E(2) and of luteal progesterone. Loss of ovarian function at the menopause likewise results in a 90% loss of circulating E(2). The consequences of loss of ovarian function during reproductive life may be severe. Symptoms include hot flushes, night sweats, vaginal dryness and dyspareunia, loss of libido, loss of bone mass with subsequent osteoporosis and abnormalities of cardiovascular function, including a substantial increase in the risk of ischemic heart disease. Various regimens of estrogen replacement have been employed, aiming to eliminate symptoms, restore well-being and avert the consequences of estrogen depletion. The commonly adopted form of replacement is with the low-dose oral contraceptive pill for reasons of convenience, cost, efficacy, general freedom from side effects and the psychological advantage that many of the patient's peer group are also "taking the pill". An often neglected aspect of hormone therapy in the reproductive age group is the therapeutic use of testosterone. The application of such principles to the postmenopausal period is more problematic, as there is a common perception that the menopause is a normal physiological occurrence and that it is therefore not physiological to offer hormone therapy at that time. The pragmatic approach is to recommend standard therapy with estrogen and progestogen for the management of menopausal symptoms and to recommend longer term hormone replacement in the light of the individual's needs and current data with regard to efficacy for protection from osteoporosis and cardiovascular disease.