Treatment of familial male precocious puberty with spironolactone and testolactone

Familial male-limited precocious puberty due to an activating mutation of the LHCGR: a case report and literature review

Familial male-limited precocious puberty (FMPP) is a rare form of gonadotropin-independent precocious puberty that is caused by an activating mutation of the LHCGR gene. Herein, we report a case of FMPP with a mutation of the LHCGR gene in a Korean boy with familial history of precocious puberty through 3 generations. A 16-month-old boy presented with signs of precocious puberty, including pubic hair, acne, and increased growth velocity. The patient's grandfather and father had a history of precocious puberty and profound short stature. On physical examination, the patient had prepubertal testes with pubic hair development appropriate for Tanner stage II. The stretched penile length was 7 cm (>2 standard deviation score), and observed bone age was that of a 4-year-old boy. Laboratory findings showed high serum testosterone (5.74 ng/mL [appropriate for Tanner IV-V]; normal range, <0.05 ng/mL) with suppressed luteinizing hormone (<0.07 mIU/mL) and normal serum level of follicular stimulating hormone (0.56 mIU/mL; normal range, 0.38-1.11 mIU/mL). Genetic testing revealed a pathogenic variant of LHCGR (c.1730 C>T (p.Thr577Ileu)), confirming FMPP. Bicalutamide and anastrozole were administered, and pubertal progression was sufficiently suppressed without any specific side effects. To our knowledge, this is the first case of genetically confirmed FMPP in Korea.

Beneficial Extracardiac Effects of Cardiovascular Medications

Cardiovascular diseases are the most common cause of death worldwide, with cardiovascular medications being amongst the most common medications prescribed. These medications have diverse effects on the heart, vascular system, as well as other tissues and organ systems. The extra cardiovascular effects have been found to be of use in the treatment of non-cardiovascular diseases and pathologies. Minoxidil is used to manage systemic hypertension with its well-known side effect of hirsutism used to treat alopecia and baldness. Sildenafil was originally investigated as a treatment option for systemic hypertension; however, its side effect of penile erection led to it being widely used for erectile dysfunction. Alpha-1 blockers such as terazosin are indicated to treat systemic hypertension but are more commonly used for benign prostatic hyperplasia and post-traumatic stress disorder. Beta blockers are the mainstay treatment for congestive heart failure and systemic hypertension but have been found useful to help in patients with intention tremors as well as prophylaxis of migraines. Similarly, calcium channel blockers are indicated in medical expulsion therapy for ureteric calculi in addition to their cardiovascular indications. Thiazides are commonly used for treating systemic hypertension and as diuretics. Thiazides can cause hypocalciuria and hypercalcemia. This side effect has led to thiazides being used to treat idiopathic hypercalciuria and associated nephrolithiasis. Spironolactone is commonly utilized in treating heart failure and as a diuretic for edema. It's well described anti-androgen side effects have been used for acne vulgaris and hirsutism in polycystic ovarian syndrome. This review article discusses how the various extracardiovascular effects of commonly used cardiovascular medications are put to use in managing non-cardiovascular conditions.

A Case of Familial Male-limited Precocious Puberty with a Novel Mutation

Familial male-limited precocious puberty (FMPP), also known as testotoxicosis, is a rare cause of precocious puberty in males. It is caused by a mutation in the luteinizing hormone/chorionic gonadotropin receptor (LHCGR) gene, resulting in the receptor being constitutively activated. This causes excessive production of testosterone, leading to precocious puberty in males. Generally, boys present with signs of puberty, such as pubic hair growth, acne, and increased height velocity around the age of 2-4 years old. Like any other cause of precocious puberty, the goal of treatment is to prevent virilization and also delay closure of the epiphyseal plates to maintain adult height potential. Treatment, therefore, is aimed at decreasing the effects of testosterone, as well as stopping the conversion of testosterone to estrogen. Little is known about the long-term effects of treatment because the disorder is so rare. However, studies using bicalutamide and anastrozole have been promising. In this report, we present a boy with FMPP with a novel mutation in the LHCGR gene, who has been responding well to therapy using both drugs.

Effect of Antiandrogen, Aromatase Inhibitor, and Gonadotropin-releasing Hormone Analog on Adult Height in Familial Male Precocious Puberty

OBJECTIVE

Antiandrogen, aromatase inhibitor, and gonadotropin-releasing hormone analog (GnRHa) treatment normalizes growth rate and bone maturation and increases predicted adult height (AH) in boys with familial male-limited precocious puberty (FMPP). To evaluate the effect of long-term antiandrogen, aromatase inhibitor, and GnRHa on AH, boys with FMPP who were treated were followed to AH.

STUDY DESIGN

Twenty-eight boys with FMPP, referred to the National Institutes of Health, were started on antiandrogen and aromatase inhibitor at 4.9 ± 1.5 years of age; GnRHa was added at 6.9 ± 1.5 years of age. Treatment was discontinued at 12.2 ± 0.5 years of age (bone age, 14.4 ± 1.3). AH was assessed at 16.4 ± 1.3 years of age (bone age, 18.5 ± 0.6).

RESULTS

AH (mean ± SD) for all treated subjects was 173.6 ± 6.8 cm (-0.4 ± 1.0 SD relative to adult US males). For 25 subjects with pretreatment predicted AH, AH significantly exceeded predicted AH at treatment onset (173.8 ± 6.9 vs 164.9 ± 10.7 cm; P < .001), but fell short of predicted AH at treatment discontinuation (177.3 ± 9.0 cm; P < .001). For 11 subjects with maternal or sporadic inheritance, the mean AH was 3.1 cm (0.4 SD score) below sex-adjusted midparental height (175.4 ± 5.8 vs 178.5 ± 3.1 cm [midparental height]; P = .10). For 16 subjects with affected and untreated fathers, AH was significantly greater than fathers' AH (172.8 ± 7.4 vs 168.8 ± 7.2 cm; P < .05).

CONCLUSIONS

Long-term treatment with antiandrogen, aromatase inhibitor, and GnRHa in boys with FMPP results in AH modestly below sex-adjusted midparental height and within the range for adult males in the general population.

Gonadotrophin-independent precocious puberty associated with later diagnosis of testicular embryonal carcinoma

BACKGROUND

Testicular tumours are very rare in children. Germ cell tumours (GCTs) account for the majority of testicular tumours in young people, and embryonal carcinomas are a common component of GCTs in adolescents.

CASE PRESENTATION

A 9.8-year-old boy presented with the development of pubic and facial hair over a period of 2 years. He had a growth spurt and examination revealed pubertal staging of G4 P4 A2 with a 6-mls testis on the right and a 4-mls testis on the left. Investigations revealed suppressed gonadotrophins, a testosterone concentration of 10.3 nmol/l and normal 17-hydroxyprogesterone and adrenal androgen levels. Tumour markers were negative. Following treatment with anastrazole, his height velocity slowed down. At the age of 13.7 years, his treatment was stopped. At the age of 14.8 years, he presented with a grossly enlarged right testis and elevated beta human chorionic gonadotrophin (>1,400 IU/l). He underwent right orchidectomy and histology revealed an embryonal carcinoma with no vascular invasion. Analysis of luteinizing hormone/choriogonadotrophin receptor revealed no mutation.

CONCLUSION

We present a case of testicular embryonal carcinoma in a boy who had presented 5 years before with features suggestive of gonadotrophin-independent precocious puberty.

Pubertal growth and serum testosterone and estradiol levels in boys

BACKGROUND/AIMS

To study serum testosterone and estradiol in healthy boys in relation to growth during puberty up to peak height velocity (PHV).

METHODS

Growth velocity was analyzed through testosterone (n = 41) and 17β-estradiol (n = 37) 24-hour profiles in a dose-response model. Participants were 26 healthy boys admitted for short or tall stature or participating as healthy volunteers at the Queen Silvia Children's Hospital. Other inclusion criteria included the following: gestational age 37-42 weeks, birth weight and length >-2 standard deviation score (SDS) and prepubertal height and weight within ± 3 SDS. Testosterone was measured using a modified radioimmunoassay (RIA) with a detection limit of 0.03 nmol/l. Estradiol was determined using an ultrasensitive extraction RIA with a detection limit 4 pmol/l. A sixth-grade polynomial was fitted to each child's growth data, giving growth velocity and age at PHV.

RESULTS

Growth velocity increased by 50% from prepubertal growth to PHV at a morning testosterone level of 3.1 nmol/l (95% confidence interval 2.4-4.2), EC50. The corresponding EC50 of 17β-estradiol was 6.5 pmol/l (3.2-13). Boys approaching PHV (<4% remaining) had morning testosterone levels >10 nmol/l and 17β-estradiol >9 pmol/l.

CONCLUSION

Observed early puberty/initial mid puberty morning testosterone levels of 2.4-4.2 nmol/l are associated with a 50% increase in growth velocity from prepubertal growth to PHV in healthy boys.

Familial male-limited precocious puberty in neurofibromatosis type I

Precocious puberty in patients with neurofibromatosis type 1 (NF-1) is predominantly central in origin, with intracranial pathologies like optic glioma. We describe one patient with NF-1 who presented with precocious puberty with the eventual diagnosis of familial male-limited precocious puberty and share the potential pitfalls. He presented at 7 years of age with growth spurt and pubertal genitalia development with enlarged testicular volume of 7 mL, but LHRH stimulation test revealed blunted luteinizing hormone and follicle-stimulating hormone peak suggestive of a peripheral cause, contrary to the expectation due to the background of NF-1. Testosterone level was elevated with bone age advancement by 2 years. Genetic analysis revealed a previously reported heterozygous missense mutation of the luteinizing hormone/choriogonadotropin receptor gene Ala572Val. His father was also heterozygous for the same mutation but was apparently asymptomatic and not short.

CONCLUSION

Our report illustrates two potential pitfalls in the clinical evaluation of patients with familial male-limited precocious puberty (FMPP). Firstly, patients with FMPP will have mild to moderately enlarged testes and should not be wrongly diagnosed as central precocious puberty without the gonadotropin-releasing hormone stimulation test. Secondly, family members with the same mutation may have different phenotypic severities, where some male carriers may have subtle features.

Behavioral aggressiveness in boys with sexual precocity

BACKGROUND

Some boys with sexual precocity are known to have behavioral problems like increased physical and verbal aggression and school and social maladjustments. It is believed to be due to premature androgen exposure. However, it is not clear why only some develop this problem, difference in etiology could be one explanation.

AIM

The aim of the study is to assess behavioral aggression in boys with sexual precocity due to different disorders.

MATERIALS AND METHODS

Seven children, ages three to seven years, were enrolled for this study. Two were diagnosed to have congenital adrenal hyperplasia (CAH), three had testotoxicosis, while two had central precocious puberty. Parents of children with precocious puberty underwent the (CASP) questionnaire (children's aggression scale-parent version).

RESULTS

Testosterone levels were high in all patients. Parents denied any history of physical or verbal aggression in the two boys with CAH. Their CASP rating was 0. In contrast, the CASP ratings in the two boys with testotoxicosis and the two with precocious puberty for five domains ranged from 3.1 - 24.2, 2.6 - 8.3,1-5.6,0 - 7.1, and 0 - 1, respectively. In the present study, increased aggression was seen among all the patients with testotoxicosis and both with precocious puberty. In contrast, there were no symptoms of either increased verbal or physical aggression in either of the two patients with CAH.

CONCLUSIONS

The hormonal milieu in the boys with CAH versus those with sexual precocity due to other causes differed in terms of cortisol and androgen precursors. The androgen excess in CAH children was a consequence of cortisol deficiency. It is possible that cortisol sufficiency is required for androgen-mediated behavioral effects.

Gender- and region-specific variations of estrogen receptor α and β expression in the growth plate of spine and limb during development and adulthood

Although estrogen action is indispensable for normal bone growth in both genders, the roles of estrogen receptors (ERs) in mediating bone growth are not fully understood. The effects of ER inactivation on bone growth are sex and age dependent, and may differ between the axial and appendicular regions. In this study, the spatial and temporal expression of ERα and β in the tibial and spinal growth plates of the female and male rats during postnatal development was examined to explore the possible mechanisms. The level of mRNA was examined and compared with quantitative real-time PCR. The spatial location was determined by immunohistochemical analysis. The 1-, 4-, 7-, 12- and 16-week age stages correspond to early life, puberty and early adulthood after puberty, respectively. Gender- and region-specific differences in ERα and β expression were shown in the growth plates. Mainly nuclear staining of ERα and β immunoreactivity was demonstrated in the spinal and tibial growth plate chondrocytes for both genders. Moreover, our study indicated significant effect of gender on temporal ERα and β expression and of region on temporal ERα/ERβ expression ratio. However, spatial differences of region-related ERα and β expression were not observed. Gender-related spatial changes were detected only at 16 weeks of both spine and limb growth plates. ERα and β immunoreactivity was detected in the resting, proliferative and prehypertrophic chondrocytes in the early life stage and during puberty. After puberty, ERα expression was mainly located in the late proliferative and hypertrophic chondrocytes in female, whereas the expression still extended from the resting to hypertrophic chondrocytes in males. Gender- and region-specific expression patterns of ERα and β gene might be one possible reason for differences in sex- and region-related body growth phenotypes. Gender, age and region differences should be taken into consideration when the roles of ERs in the growth plate are investigated.

Aromatase inhibitors in pediatrics

Aromatase, an enzyme located in the endoplasmic reticulum of estrogen-producing cells, catalyzes the rate-limiting step in the conversion of androgens to estrogens in many tissues. The clinical features of patients with defects in CYP19A1, the gene encoding aromatase, have revealed a major role for this enzyme in epiphyseal plate closure, which has promoted interest in the use of inhibitors of aromatase to improve adult height. The availability of the selective aromatase inhibitors letrozole and anastrozole--currently approved as adjuvant therapy for breast cancer--have stimulated off-label use of aromatase inhibitors in pediatrics for the following conditions: hyperestrogenism, such as aromatase excess syndrome, Peutz-Jeghers syndrome, McCune-Albright syndrome and functional follicular ovarian cysts; hyperandrogenism, for example, testotoxicosis (also known as familial male-limited precocious puberty) and congenital adrenal hyperplasia; pubertal gynecomastia; and short stature and/or pubertal delay in boys. Current data suggest that aromatase inhibitors are probably effective in the treatment of patients with aromatase excess syndrome or testotoxicosis, partially effective in Peutz-Jeghers and McCune-Albright syndrome, but probably ineffective in gynecomastia. Insufficient data are available in patients with congenital adrenal hyperplasia or functional ovarian cysts. Although aromatase inhibitors appear effective in increasing adult height of boys with short stature and/or pubertal delay, safety concerns, including vertebral deformities, a decrease in serum HDL cholesterol levels and increase of erythrocytosis, are reasons for caution.

Psychiatric characterization of children with genetic causes of hyperandrogenism

OBJECTIVE

Very little is known about the mental health status in children with genetic causes of hyperandrogenism. This study sought to characterize psychiatric morbidity in this group.

DESIGN/METHODS

Children (8-18 years) with the diagnosis of classic congenital adrenal hyperplasia (CAH) or familial male precocious puberty (FMPP) underwent a semi-structured psychiatric interview, the Kiddie Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version. According to sex and the literature, incidence of identified psychopathology was compared between the two endocrinological groups. We evaluated 72 patients: 54 CAH (21 females) and 18 FMPP.

RESULTS

Twenty-four (44.4%) CAH patients and 10 (55.6%) FMPP patients met the criteria for at least one lifetime psychiatric diagnosis. Attention-deficit hyperactivity disorder (ADHD) was present in 18.2% of CAH males, 44.4% of FMPP males, and one case (4.8%) in CAH females. A high rate of anxiety disorders was also found in all the three groups (17-21%). Relative to females with CAH, the FMPP patients exhibited higher rates of ADHD. Age at diagnosis and the treatment modalities were not associated with psychopathology. Rates of psychiatric disorder, specifically ADHD and anxiety disorders, were higher than in the general population.

CONCLUSION

Although anxiety disorders may occur at an increased rate in children with chronic illness, androgens may contribute to higher risk for psychopathology in pediatric patients with genetic cause of excess androgen. Early diagnosis and treatment of childhood hyperandrogenism is essential for optimal development. The results suggest that assessment for psychiatric disorders should be part of the routine evaluation of these patients.

Bicalutamide plus anastrozole for the treatment of gonadotropin-independent precocious puberty in boys with testotoxicosis: a phase II, open-label pilot study (BATT)

OBJECTIVE

To evaluate the efficacy, tolerability, and pharmacokinetics of bicalutamide plus anastrozole in young males with testotoxicosis.

METHODS

This was a multicenter, open-label, single-arm, 12-month, Phase II pilot trial in 14 males (2-9 years) with testotoxicosis treated with bicalutamide (12.5, 25, 50, or 100 mg) and anastrozole (0.5 or 1 mg) daily. The primary outcome was change in growth rate.

RESULTS

At 1 year, the mean (standard deviation) change from baseline in growth rate was -1.6 (+/- 5.1) cm/year and -0.1 (+/- 1.8) SD units, and in bone maturation was -2.3 (+/- 0.5) years. The bone age/chronological age ratio was reduced from 2.1 (+/- 0.6) at baseline to 1.0 (+/- 0.4) (p = 0.00013). Steady-state trough R-bicalutamide and anastrozole concentrations were attained by Day 21 and 8, respectively. Gynecomastia (42.9%) and breast tenderness (12.5%) were the most common treatment-related adverse events.

CONCLUSIONS

Treatment of testotoxicosis with bicalutamide plus anastrozole resulted in slower growth rate.

Bicalutamide and third-generation aromatase inhibitors in testotoxicosis

Testotoxicosis, a form of gonadotropin-independent precocious puberty, results from an activating mutation of the luteinizing hormone receptor expressed in testicular Leydig cells. Affected males experience early testosterone secretion, virilization, advancing bone age, and resultant short stature. Recently, the use of combination therapy with a potent antiandrogen agent (bicalutamide) and a third-generation aromatase inhibitor (anastrozole or letrozole) was reported to yield encouraging short-term results. We present here the results of longer-term treatment (4.5 and 5 years) with this combination therapy in 2 boys who demonstrated that it is well tolerated, slows bone-age advancement in the face of continued linear growth, and prevents progression of virilization.

Growth-attenuation therapy: principles for practice

Publication of an account of growth attenuation with high-dose estrogen in a child with profound physical and cognitive disability brought widespread attention to a common and complex issue faced by families caring for similarly affected children, namely, the potentially negative effect of the increasing size of a child on the ability of his or her family to provide independent care, which in turn makes it more difficult for parents to keep the child in the home and involved in family activities. In this article we explore the scientific rationale for, effectiveness and safety of, and ethical considerations bearing on growth-attenuation treatment of children with profound and permanent cognitive disability. Informed responses to key clinically relevant questions are proposed. Our analysis suggests that growth attenuation is an innovative and sufficiently safe therapy that offers the possibility of an improved quality of life for nonambulatory children with profound cognitive disability and their families. Pediatricians and other care providers should include discussion of these options as part of anticipatory guidance around the age of 3 years so that, if elected, potential clinically meaningful benefits of growth-attenuation therapy can be realized. Because of the publicity and debate surrounding the first reported case, ethics consultation is recommended.

Early hyperandrogenism affects the development of hippocampal function: preliminary evidence from a functional magnetic resonance imaging study of boys with familial male precocious puberty

The way in which sex hormones influence cognitive and affective brain development is poorly understood. Despite increasing knowledge in the area of pediatric mood disorders, little is known about the influence of sex hormones on the regulation of emotion. Animal studies and preliminary human studies suggest a strong impact of testosterone on limbic structures such as the hippocampus and amygdala. We used functional magnetic resonance imaging (fMRI) to examine emotional processing in familial male-precocious puberty (FMPP), an extremely rare gonadotropin-independent form of precocious puberty characterized by early excess testosterone secretion. We compared this group (n = 7, mean age = 13 +/- 3.3 years) to healthy age and sex-matched controls (n = 14, mean age = 13 +/- 2.3 years). Participants were presented with emotional and neutral face stimuli and were required either to judge the hostility of the presented face, their subjective level of anxiety, or the width of the nose of the presented faces (nonemotional condition). In a fourth, passive viewing condition, no responses were required. Boys with FMPP responded faster to fearful faces during perception of threat compared to unaffected controls. Concurrently, fMRI data revealed significant differences in hippocampus activation in response to fearful faces relative to baseline whereas controls showed no differences. In contrast, no significant activation of the amygdala was found. These data are consistent with previous studies of the effects of sex hormones on brain function and support the role of testosterone on emotional development.

Long-term treatment of familial male-limited precocious puberty (testotoxicosis) with cyproterone acetate or ketoconazole

BACKGROUND

Familial male-limited precocious puberty (FMPP) or testotoxicosis is a rare gonadotrophin-independent form of sexual precocity caused by constitutively activating mutations of the LH receptor. Several clinical therapeutic approaches have been reported for this disorder, but with a paucity of long-term outcome data.

OBJECTIVE

To evaluate the long-term treatment of testotoxicosis with cyproterone acetate or ketoconazole.

DESIGN

A multicentric retrospective clinical study.

PATIENTS

Ten boys from eight unrelated Brazilian families who carried known LH-receptor activating mutations were treated with 70 mg/m(2) cyproterone acetate (n = 5) or 10 mg/kg ketoconazole (n = 5) for a mean period of 5 and 8 years, respectively.

MEASUREMENTS

Chronological and bone ages, bone age/chronological age ratio, target height (TH) range, adult height, basal and GnRH-stimulated gonadotrophin levels and basal testosterone levels were assessed.

RESULTS

Growth velocity decreased significantly during treatment with cyproterone acetate or ketoconazole when compared to pretreatment value in each group (P < 0.05). Bone age/chronological age ratio decreased significantly after cyproterone acetate or ketoconazole therapy. Basal testosterone levels were significantly lower in patients undergoing ketoconazole compared to cyproterone acetate treatment [0.6 +/- 0.3 nmol/l (42 +/- 21 ng/dl) vs. 5.6 +/- 4.0 nmol/l (392 +/- 280 ng/dl); P < 0.05], as expected. Secondary gonadotrophin-dependent precocious puberty occurred at a similar frequency (40%) in both groups. Five patients have attained adult height and two patients have already reached 90% of their adult height. Two of them achieved their TH range and one patient, for whom TH was not available, had an adult height of 0.3 SDS. Four boys (two in each group) did not attain their TH range.

CONCLUSION

Long-term treatment with cyproterone acetate or ketoconazole resulted in similar outcomes without important side-effects in boys with testotoxicosis. However, both therapies showed limited efficacy in attaining normal adult height.

Use of aromatase inhibitors in children and adolescents with disorders of growth and adolescent development

Although treatment of children and adolescents who have disorders of growth and adolescent development with aromatase inhibitors is increasingly common, data for or against their use are extremely limited. Precocious puberty, short stature, and gynecomastia are conditions for which inhibition of the enzyme aromatase might prove beneficial to reduce clinical signs of estrogenization and/or estrogen-mediated skeletal maturation. In this report, we summarize the published data regarding the use of aromatase inhibitors in these conditions, and review known and potential benefits, safety concerns, and shortcomings of the available information.

Use of aromatase inhibitors to increase final height

During puberty in both sexes, the mechanism involved in epiphyseal fusion is mediated by the action of estrogen through a cascade of events including proliferation, differentiation, and apoptosis of chondrocytes. The enzyme P450 aromatase catalyzes the aromatization of C19 androgens (androstenedione and testosterone) to C18 estrogens (estrone and estradiol). Inhibition of estrogen action by aromatase inhibitors (AIs) appears to decelerate the process of growth plate fusion, and thus AIs may be used therapeutically to increase adult height. The clinical experience with AIs in the pediatric setting is limited to testolactone, fadrozole, letrozole, and anastrozole. Testolactone, a nonselective steroidal AI, has been used successfully as an adjunct to antiandrogen and gonadotropin-releasing hormone analogue (GnRHa), therapy for children with familial male-limited precocious puberty (FMPP) and congenital adrenal hyperplasia (CAH), and with some success in girls with McCune-Albright syndrome. The limitations of testolactone include its relatively low potency and the need for frequent dosing. Results of a randomized placebo-controlled trial in boys with delayed puberty treated with letrozole, a selective nonsteroidal AI, found that boys treated with letrozole + testosterone experienced delayed bone maturation and good growth response and achieved an increase in predicted adult height. In this study, only minor differences in bone density were seen between the placebo and letrozole treatment groups, both of which were receiving concomitant testosterone therapy. No adverse effects on testis size or inhibin B concentration were noted. The therapeutic value of AIs in growth promotion now remains to be substantiated in future controlled clinical trials.

Precocious pseudopuberty with testicular enlargement

Gonadotropins independent precocious puberty (GIPP) in male is characterized by early appearance of sexual hairs and phallic growth but without testicular enlargement. We report a case of GIPP with testicular enlargement who was diagnosed to have testotoxicosis and successfully managed with spironolactone.

Estrogen in men: effects on bone accrual, maintenance and prevention of bone loss

Sex steroid hormones play an important role in the maintenance of bone mass in males as well as in females. Even though androgens represent the major sex steroid class in men, their primacy in regulating male skeletal remodeling has been questioned increasingly as direct and indirect evidence has emerged suggesting that estrogens also play a major role in male skeletal health. This review summarizes clinical and experimental evidence that estrogens are essential for bone accrual in the growing skeleton, maintenance of bone mass and prevention of bone loss in men.

Endocrine regulation of the growth plate

Longitudinal bone growth occurs at the growth plate by endochondral ossification. Within the growth plate, chondrocyte proliferation, hypertrophy, and cartilage matrix secretion result in chondrogenesis. The newly formed cartilage is invaded by blood vessels and bone cells that remodel the newly formed cartilage into bone tissue. This process of longitudinal bone growth is governed by a complex network of endocrine signals, including growth hormone, insulin-like growth factor I, glucocorticoid, thyroid hormone, estrogen, androgen, vitamin D, and leptin. Many of these signals regulate growth plate function, both by acting locally on growth plate chondrocytes and also indirectly by modulating other endocrine signals in the network. Some of the local effects of hormones are mediated by changes in paracrine factors that control chondrocyte proliferation and differentiation. Many human skeletal growth disorders are caused by abnormalities in the endocrine regulation of the growth plate. This review provides an overview of the endocrine signals that regulate longitudinal bone growth, their interactions, and the mechanisms by which they affect growth plate chondrogenesis.

Aromatase Inhibitors in Precocious Puberty

Aromatase inhibitors have been used in the treatment of selective forms of precocious puberty since the mid-1980s. The primary aim of therapy is attenuation of the effects of estrogen on growth, skeletal maturation, and secondary sexual development. The first-generation agent, testolactone, has been demonstrated to be tolerable and effective in the treatment of familial male precocious puberty, while mixed results with testolactone have been achieved in girls with McCune-Albright syndrome. A favorable outcome with the use of testolactone in conjunction with conventional therapy in children with congenital adrenal hyperplasia has also been suggested. Although a few anecdotal reports of the use of newer generation aromatase inhibitors in precocious puberty exist, the extreme rarity of the relevant disorders remains a limiting factor in clinical investigation. In this review, the pathophysiology, presentation, and treatment of precocious puberty are described. Particular attention is devoted to the specific disorders in which aromatase inhibitors have been utilized, which are forms of peripheral (gonadotropin-independent) precocious puberty. The impact of untreated precocious puberty on growth and adult stature is discussed, and the actions of estrogen in the human skeleton are summarized. Finally, a detailed description of the existing literature pertaining to aromatase inhibitors in the pediatric population is provided. Emerging potential new indications are discussed. In conclusion, aromatase inhibitors, particularly testolactone, have a proven track record in the treatment of a few forms of precocious puberty. Continued exploration with new generation aromatase inhibitors in these disorders is ongoing. The wider application of aromatase inhibitors for the purposes of delaying skeletal maturation and increasing adult height in several conditions leading to short stature is currently a subject of intense investigation.

Role of estrogen and androgen in pubertal skeletal physiology

Since both estrogen and androgen are present in each sex, it has been difficult to discern the exact role that each sex steroid plays in skeletal physiology. However, studying clinical syndromes in which there is either only estrogen or androgen action has allowed us to gain insight into the unique role that each sex steroid plays in the growing skeleton. In complete androgen insensitivity syndrome (AIS) the only functional sex steroid receptor is that for estrogen. Effected XY females have a pubertal growth spurt that is typical of normal females, both in magnitude and timing. Individuals with AIS have a mild reduction in bone density but it is difficult to distinguish whether this is the result of androgen resistance or estrogen deficiency. These observations suggest that estrogen action only is sufficient to induce a normal pubertal growth spurt, epiphyseal maturation, and near normal bone mineral accretion in women. Until recently, the skeletal effects of estrogen were not thought to be of importance in the male. Conventional wisdom dictated that, in the male, testosterone mediated these skeletal changes. The notion that estrogen is of little importance in the male has been challenged by the recent discovery of two human syndromes in which estrogen action is lacking. In males with either estrogen resistance (inability to respond to circulating estrogen) or aromatase deficiency (inability to synthesize estradiol), as a result of the lack of estrogen action, a pubertal growth spurt does not appear to occur. Furthermore, complete epiphyseal maturation does not take place allowing for continued growth in adulthood and resultant tall stature. Finally normal bone mineral accretion does not take place resulting in severe osteoporosis. These findings indicate that estrogen plays a critical role in skeletal physiology of males as well as females.

Combined treatment with testosterone (T) and ethinylestradiol (EE2) in constitutionally tall boys: is treatment with T plus EE2 more effective in reducing final height in tall boys than T alone?

Estrogens have been shown to rapidly inhibit longitudinal growth in tall boys. To antagonize the initial growth accelerating effect of T, 41 boys with an initial height prediction in excess of 203 cm were treated prospectively with either T enanthate (TE) 250 mg/wk im in combination with ethinylestradiol (EE2) 0.1 mg/d taken orally for the first 5.8 +/- 0.47 wk (mean +/- SE) of treatment (group 1, n = 20) or with TE alone (group 2, n = 21). Patients were randomized to one or the other treatment regimen. Mean (+/-SE) predicted adult height was 206.8 +/- 0.7 cm in group 1 and 206.4 +/- 0.8 cm in group 2. Total duration of treatment was 16.1 +/- 0.8 months and 14.0 +/- 1.2 months in group 1 and 2, respectively (NS). EE2-induced side effects in group 1 (gynecomastia) were limited and fully reversible. No negative long-term sequelae were found at final height with respect to hypothalamic-pituitary-gonadal axis activity and to testis volumes. Although there was a tendency to a lower initial growth velocity measured by knemometry in group 1 (0.30 +/- 0.05 vs. 0.38 +/- 0.05 mm/wk, NS), final height did not differ in both study groups (195.0 +/- 0.8 cm in group 1, 194.6 +/- 0.8 cm in group 2). Similarly, height reduction (initial predicted adult height minus final height) was not significantly different between the two groups (12.0 +/- 0.9 cm in group 1, 11.7 +/- 0.9 cm in group 2). In conclusion, the addition of EE2 during the initial treatment phase to high-dose T in tall boys has no significant effect on height reduction. The results of this clinical trial suggest that the initial growth inhibiting effect of EE2 on the epiphyseal growth plates is overridden by the long-term administration of high dose TE.

Congenital adrenal hyperplasia owing to 21-hydroxylase deficiency. Growth, development, and therapeutic considerations

In the absence of long-term results of experimental therapies, a common sense approach toward dealing with the growth of patients who have CAH is desirable. First, an effort can be made to decrease the replacement cortisol dose during the first year of life. Doubling, rather than tripling, the basal dose at times of stress could be helpful. The use of adjunctive therapy for infections could result in fewer fevers. After 1 year of age, mean parental height could be used to establish at which centile the child should theoretically grow. The dose of cortisol could be adjusted to maintain the bone age between +/- 1 SD. Plasma androstenedione levels should not rise above 50 ng/dL, and 17-hydroxyprogesterone should not be totally suppressed but be maintained between 500 and 1000 ng/dL. Compliance with therapy should be encouraged, particularly for adolescent patients. In the final analysis, a realistic expectation for patients would be a height between the 50th and third percentile of the normal growth curve and, in some cases, slightly below the third percentile when the genetic potential is slight.

New ideas for medical treatment of congenital adrenal hyperplasia

During the past 50 years since the discovery of cortisone therapy as an effective treatment for CAH, many advances have been made in the management of 21-hydroxylase deficiency. Despite these advances, the clinical management of patients with CAH is often complicated by abnormal growth and development, iatrogenic Cushing's syndrome, inadequately treated hyperandrogenism, and infertility. New treatment approaches to classic CAH represent potential solutions to these unresolved issues. At the National Institutes of Health, a long-term randomized clinical trial is investigating a new treatment regimen: a reduced hydrocortisone dose, an antiandrogen, and an aromatase inhibitor. Peripheral blockade of androgens may also be helpful in the adult woman with CAH and PCOS. Other promising new treatment approaches include LHRH agonist-induced pubertal delay with or without growth hormone therapy, alternative glucocorticoid preparations or dose schedules, CRH antagonist treatment, and gene therapy. The applicability and success of these new approaches await the results of current research.

Flutamide, testolactone, and reduced hydrocortisone dose maintain normal growth velocity and bone maturation despite elevated androgen levels in children with congenital adrenal hyperplasia

Treatment outcome in congenital adrenal hyperplasia is often sub-optimal due to hyperandrogenism, treatment-induced hypercortisolism, or both. We previously reported better control of linear growth, weight gain, and bone maturation in a short term cross-over study of a new four-drug treatment regimen containing an antiandrogen (flutamide), an inhibitor of androgen to estrogen conversion (testolactone), reduced hydrocortisone dose, and fludrocortisone, compared to the effects of a control regimen of hydrocortisone and fludrocortisone. Twenty-eight children have completed 2 yr of follow-up in a subsequent long term randomized parallel study comparing these two treatment regimens. During 2 yr of therapy, compared to children receiving hydrocortisone, and fludrocortisone treatment, children receiving flutamide, testolactone, reduced hydrocortisone dose (average of 8.7 +/- 0.6 mg/m2 x day), and fludrocortisone had significantly (P < or = 0.05) higher plasma 17-hydroxyprogesterone, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and testosterone levels. Despite elevated androgen levels, children receiving the new treatment regimen had normal linear growth rate (at 2 yr, 0.1 +/- 0.5 SD units), and bone maturation (at 2 yr, 0.7 +/- 0.3 yr bone age/yr chronological age). No significant adverse effects were observed after 2 yr. We conclude that the regimen of flutamide, testolactone, reduced hydrocortisone dose, and fludrocortisone provides effective control of congenital adrenal hyperplasia with reduced risk of glucocorticoid excess. A long term study of this new regimen is ongoing.

The effects of gonadectomy on bone size, mass, and volumetric density in growing rats are gender-, site-, and growth hormone-specific

Peak volumetric bone mineral density (BMD) is determined by the growth in bone size relative to the mineral accrued within its periosteal envelope. Thus, reduced peak volumetric BMD may be the result of reduced mineral accrual relative to growth in bone size. Because sex steroids and growth hormone (GH) influence bone size and mass we asked: What are the effects of gonadectomy (Gx) on bone size, bone mineral content (BMC), areal and volumetric BMD in growing male and female rats? Does GH deficiency (GH-) reduce the amount of bone in the (smaller) bone, i.e., reduce volumetric BMD? Does GH- alter the effect of Gx on bone size and mineral accrual? Gx or sham surgery was performed at 6 weeks in GH- and GH replete (GH+) Fisher 344 male and female rats. Changes in bone size, volume, BMC, areal and volumetric BMD, measured using dual X-ray absorptiometry (DPX-L), were expressed as percentage of controls at 8 months (mean +/- SEM). All results shown were significant (p < 0.05 level) unless otherwise stated. In GH+ and GH- males, respectively, Gx was associated with: lower femur volume (24%, 25%), BMC (43%, 45%), areal BMD (21%, 14%), and volumetric BMD (30%, 28%); lower spine (L1-L3) volume (26%, 28%), BMC (26%, 30%), and areal BMD (28%, 12%), but not volumetric BMD. Following Gx, GH+ females had increased femur volume (11%), no effect on BMC, decreased areal BMD (6%) and decreased volumetric BMD (17%); GH- females had no change in femur volume, but decreased femur BMC (24%), areal BMD (10%), and volumetric BMD (25%). In GH+ and GH- females, respectively, Gx was associated with a decrease in spine (L1-L3) BMC (12%, 15%), areal BMD (16%, 15%), and volumetric BMD (10%, 16%) with no change in volume. Deficits in non-Gx GH- relative to non-Gx GH+ (males, females, respectively) were: femur BMC (49%, 37%), areal BMD (23%, 8%), volume (19%, 19%) and volumetric BMD (37%, 22%); spine (L1-L3) BMC (46%, 42%), areal BMD (37%, 43%), volume (10%, 15%), and volumetric BMD (40%, 33%). Testosterone and GH are growth promoting in growing male rats, producing independent effects on bone size and mass; deficiency produced smaller appendicular bones with reduced volumetric BMD because deficits in mass were greater than deficits in size. At the spine, the reduction in size and accrual were proportional, resulting in a smaller bone with normal volumetric BMD. In growing female rats, estrogen was growth limiting at appendicular sites; deficiency resulted in a GH-dependent increase in appendicular size, relatively reduced accrual, and so, reduced volumetric BMD in a bigger bone. At the spine, accrual was reduced while growth in size was normal, thus volumetric BMD was reduced in the normal sized bone. Understanding the pathogenesis of low volumetric BMD requires the study of the differing relative growth in size and mass of the axial and appendicular skeleton in the male and female and the regulators of the growth of these traits.

Spontaneous growth and bone age development in a patient with 17alpha-hydroxylase deficiency: evidence of the role of sexual steroids in prepubertal bone maturation

A male pseudohermaphrodite with 17alpha-hydroxylase deficiency and complete nonvirilization was monitored for excessive weight from the age of 3.5 to 11.5 years before the absence of sex steroids was detected. The retrospective analysis of growth data showed retarded bone age development despite adequate growth, which led to a remarkable increase in final height prognosis.

The roles of oestrogen in the male

Roles for oestrogens in brain masculinization/sexual behaviour, regulation of follicle-stimulating hormone (FSH)secretion and Leydig cell development and function are well established. However, the widespread distribution of oestrogen receptors alpha and beta in reproductive and other tissues of the male, and findings from human males or transgenic animals in which the genes coding for these receptors or for aromatase are non-functional, are changing our perception of the roles of oestrogen in the male. Aspects of pubertal development in boys (growth of the long bones, their mineralization and epiphyseal closure) attributed to the actions of androgens are now recognized as being mediated in part by oestrogens. Oestrogens also play a role (probably vasodilatatory) in the cardiovascular system of the male. Within the reproductive system, oestrogens have been shown to play a role in the regulation of fluid resorption from the efferent ducts and appear to be important in the structural and functional development of the Wolffian/excurrent duct system, as well as that of the prostate; inappropriately low or high oestrogen exposure during development can cause permanent changes to these tissues, which may lead to disorders of spermatogenesis and infertility. Sertoli cells and certain germ cells in the testis are also targets for oestrogen action. Many other tissues (adipose, kidney, thymus/immune system, skin, gut and muscle) are oestrogen targets in the male. Based on these findings and the widespread distribution of aromatase, it is argued that many of the effects of oestrogens in the male might stem from its local production and action and, furthermore, that the balance in action between androgens and oestrogens might be of central importance at many oestrogen target sites.

Testolactone-associated high androgen levels, a pharmacologic effect or a laboratory artifact?

Testolactone, an aromatase inhibitor, blocks conversion of androgens to estrogens. In familial male precocious puberty, slowing of pubertal progression and growth velocity occurs with testolactone and spironolactone. Girls with McCune-Albright syndrome, given testolactone, respond similarly. A 2-yr-old female (case 1) on testolactone for non-McCune-Albright gonadotropin independent precocious puberty had marked elevations of androstenedione (18 ng/mL, normal: 0.2-3.1) and testosterone (3.6 ng/mL, normal < 0.2) but no virilization. Investigations were undertaken to determine whether elevations in testosterone and androstenedione were caused by interference in these RIAs. After a single oral dose of testolactone (5 mg/kg in case 1; 4 mg/kg in case 2, a 3-yr-old boy with familial male precocious puberty; 10 mg/kg in a healthy postmenopausal control), serum testosterone and androstenedione were measured serially by RIA for 24 h. Androstenedione went from normal to a mean peak of 45.4 ng/mL at 1-2 h and returned to baseline by 24 h. Testosterone, undetectable at baseline (case 1 and control) or 1.8 ng/mL (case 2) rose to a mean peak of 6.9 ng/mL and returned to baseline by 24 h. Testolactone, in serial dilutions, cross-reacted in the testosterone assay. Testolactone significantly interferes in these serum RIAs, making their use unreliable in follow-up of patients treated with testolactone.

Oestrogen receptor deficiency: consequences for growth

These oestrogen-resistant and aromatase-deficient cases now establish a more complete picture of how androgen and oestrogen combine to regulate pubertal growth (47, 48) and demonstrate that oestrogen deficiency states need not be lethal (1). Whereas original concepts suggested that skeletal maturation and pubertal growth were attributable to androgen and, therefore, were not sexually dimorphic, current evidence preserves the notion of common mechanisms in both sexes, but points to oestrogen as the principal steroid involved in the final phases of skeletal maturation. Oestrogen can be viewed as a primary determinant of the final height of a child, in the sense that oestrogen initiates and completes epiphyseal closure. The full scope of the effects of androgen on epiphyseal maturation and linear height regulation is less clear but evidence suggests that androgen has direct and indirect effects through its aromatization to oestrogen (Fig. 2). Remarkably, under unusual circumstances, a rather prolonged period of continued growth can be achieved with minimal bone-age advancement, as long as oestrogen concentrations and/or sensitivity are low. Given this more complete understanding of the role of oestrogen, and with the availability of more sensitive assays for oestradiol (49), a new era in sex-steroid physiology and pubertal growth has been inaugurated (50). However, any therapies directed towards manipulating growth with sex steroids will need to take account of the possibility of untoward effects on other processes, such as the accretion of bone mineral mass (51,52).

The role of estrogen in pubertal skeletal physiology: epiphyseal maturation and mineralization of the skeleton

The year 1994 is likely to be remembered by many endocrinologists as the year in which dramatic new light was shed on the role played by estrogen in human skeletal physiology. It was in 1994 that two new syndromes were described, each representing a human model in which estrogen action was lacking. The first case was a female with an aromatase defect and a resultant inability to synthesize estrogen, and the second case was a man with an estrogen receptor gene defect that resulted in a non-functioning estrogen receptor and complete estrogen resistance. By examining the phenotypes of these two individuals, we were able, for the first time, to see what pubertal skeletal changes occur in the absence of estrogen action and directly extrapolate the role of estrogen in skeletal physiology. What has become abundantly clear is that it is estrogen and not androgen that is responsible for pubertal epiphyseal maturation and skeletal mineralization.

Corticosteroid receptor antagonists: a current perspective

This review aims to highlight a selection of antagonists for the mineralocorticoid and glucocorticoid receptors. Concepts of these receptor systems are described, as is the mechanism of action of these steroids in the brain and periphery. Examples of commonly available and newly synthesized antimineralocorticoids and antiglucocorticoids are given, together with their pharmacological profiles and, when appropriate, clinical and therapeutic applications.

Genetic heterogeneity of constitutively activating mutations of the human luteinizing hormone receptor in familial male-limited precocious puberty

Genomic DNA from 32 unrelated families with male-limited precocious puberty was examined for the previously described Asp-578-->Gly, Met-571-->Ile, and Thr-577-->Ile mutations in transmembrane helix 6 of the human luteinizing hormone receptor (hLHR). Twenty-eight families had the inherited form of the disorder, and of these, 24 were found to have the Asp-578-->Gly mutation. Four additional mutations were found among the remaining four families with the inherited form and in four sporadic cases of the disorder: an A-->C transversion resulting in substitution of leucine for Ile-542 in the fifth transmembrane helix, an A-->G transition resulting in substitution of glycine for Asp-564 in the third cytoplasmic loop, a G-->T transversion resulting in substitution of tyrosine for Asp-578 in the sixth transmembrane helix, and a T-->C transition resulting in substitution of arginine for Cys-581 in the sixth transmembrane helix. Human embryonic kidney cells transfected with cDNAs for each of the mutant hLHRs, created by PCR-based mutagenesis of the wild-type hLHR cDNA, exhibited increased levels of basal cAMP production in the absence of agonist, indicating constitutive activation of the mutation hLHRs. Three of the additional mutations had specific features: Ile-542-->Leu and Cys-581-->Arg appeared ligand-unresponsive, whereas Asp-578-->Tyr appeared to correlate genotype with phenotype. We conclude that the region spanning nt 1624-1741 of exon 11 is a hotspot for heterogeneous point mutations that constitutively activate the hLHR and cause male-limited precocious puberty.

Estrogen resistance caused by a mutation in the estrogen-receptor gene in a man

BACKGROUND AND METHODS

Mutations in the estrogen-receptor gene have been thought to be lethal. A 28-year-old man whose estrogen resistance was caused by a disruptive mutation in the estrogen-receptor gene underwent studies of pituitary-gonadal function and bone density and received transdermal estrogen for six months. Estrogen-receptor DNA, extracted from lymphocytes, was evaluated by analysis of single-strand-conformation polymorphisms and by direct sequencing.

RESULTS

The patient was tall (204 cm [80.3 in.]) and had incomplete epiphyseal closure, with a history of continued linear growth into adulthood despite otherwise normal pubertal development. He was normally masculinized and had bilateral axillary acanthosis nigricans. Serum estradiol and estrone concentrations were elevated, and serum testosterone concentrations were normal. Serum follicle-stimulating hormone and luteinizing hormone concentrations were increased. Glucose tolerance was impaired, and hyperinsulinemia was present. The bone mineral density of the lumbar spine was 0.745 g per square centimeter, 3.1 SD below the mean for age-matched normal women; there was biochemical evidence of increased bone turnover. The patient had no detectable response to estrogen administration, despite a 10-fold increase in the serum free estradiol concentration. Conformation analysis of his estrogen-receptor gene revealed a variant banding pattern in exon 2. Direct sequencing of exon 2 revealed a cytosine-to-thymine transition at codon 157 of both alleles, resulting in a premature stop codon. The patient's parents were heterozygous carriers of this mutation, and pedigree analysis revealed consanguinity.

CONCLUSIONS

Disruption of the estrogen receptor in humans need not be lethal. Estrogen is important for bone maturation and mineralization in men as well as women.

Hazards of ketoconazole therapy in testotoxicosis

An eight-year-old boy with Leydig cell hyperplasia (testotoxicosis) was admitted with a three-day history of rash, vomiting and diarrhoea, followed by acute onset of breathlessness and confusion. He was shocked, with liver cell and renal failure, erythematous rash and severe interstitial pneumonitis. He had been treated with ketoconazole for four years prior to admission, receiving 1200mg daily during the preceding year. Cessation of ketoconazole therapy was associated with full clinical recovery but relapse of testotoxicosis. Ketoconazole was reintroduced cautiously at a lower dose, with no ill-effect, and reasonable control of testotoxicosis. We conclude that this boy's illness, including the interstitial pneumonitis, represented a reaction to ketoconazole which was dose-related rather than idiosyncratic.

Familial testotoxicosis in a Chinese family

We report two cases of 'familial testotoxicosis' in a family of Southern Chinese descent. The proband, an 8-year 4-month-old boy and his 35-year-old father both presented with early sexual development. In both cases the testicular volume was only 6 ml despite fully developed secondary sexual characteristics. Both patients had adult testosterone concentrations but a suppressed gonadotrophin response to gonadotrophin-releasing hormone. The suppressed gonadotrophin response to gonadotrophin-releasing hormone in the father suggests that autonomous gonadal production of sex steroid by the testes can persist well into adult life in some patients with familial testotoxicosis.

A constitutively activating mutation of the luteinizing hormone receptor in familial male precocious puberty

Familial male precocious puberty (FMPP) is a gonadotropin-independent disorder that is inherited in an autosomal dominant, male-limited pattern. Affected males generally exhibit signs of puberty by age 4. Testosterone production and Leydig cell hyperplasia occur in the context of prepubertal levels of luteinizing hormone (LH). The LH receptor is a member of the family of G-protein-coupled receptors, and we hypothesized that FMPP might be due to a mutant receptor that is activated in the presence of little or no agonist. A single A-->G base change that results in substitution of glycine for aspartate at position 578 in the sixth transmembrane helix of the LH receptor was found in affected individuals from eight different families. Linkage of the mutation to FMPP was supported by restriction-digest analysis. COS-7 cells expressing the mutant LH receptor exhibited markedly increased cyclic AMP production in the absence of agonist, suggesting that autonomous Leydig cell activity in FMPP is caused by a constitutively activated LH receptor.