Delayed Puberty Including Constitutional Delay: Differential and Outcome

Constitutional delay of growth and puberty (CDGP) is the most common cause of delayed puberty in both male and female individuals. This article reviews the causes of delayed puberty focusing on CDGP, including new advances in the understanding of the genetics underpinning CDGP, a clinical approach to discriminating CDGP from other causes of delayed puberty, outcomes, as well as current and potential emerging management options.

Impact of Cushing's syndrome on the gonadotrope axis and testicular functions in men

STUDY QUESTION

Does Cushing's syndrome (CS) differently affect the gonadotrope axis and testicular functions (GA/TF) according to the hypercortisolism intensity and underlying etiology?

SUMMARY ANSWER

Endogenous cortisol excess caused by CS leads to varying degrees of hypogonadotropic hypogonadism (HH) with more severe GA/TF impairment and altered spermatogenesis in men with intense hypercortisolism associated with paraneoplastic/ectopic adrenocorticotrophic hormone (ACTH) secretion (EAS).

WHAT IS KNOWN ALREADY

CS is very rarely studied in men due to its lower prevalence in men than in women. In a few old reports focusing exclusively on a limited number of men with Cushing's disease (CD), the occurrence of hypogonadism was reported. However, a detailed assessment of the impact of CS on the GA/TF in a significant series of patients has not been performed. Yet, hypogonadism could worsen CS-associated comorbidities such as osteoporosis and myopathy. To date, the full spectrum of GA/TF impairment in men with CS of different etiologies and intensity remains unknown.

STUDY DESIGN, SIZE, DURATION

In this monocentric study, 89 men with CS diagnosed at a tertiary endocrine university center (Bicêtre, Paris Saclay) between January 1990 and July 2021 were evaluated and compared to 40 normal men of similar age.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The CS patient cohort of 89 men included 51 with CD, 29 with EAS and 9 with CS of adrenal origin i.e. (ACTH-independent CS (AI-CS)). They all had frank hypercortisolism, with increased 24 h-urinary-free cortisol (24 h-UFC) in two separate samples. A case-control study was performed focusing on pituitary gonadotrope function and testicular sex steroids and peptides. An additional set of six CS men had an evaluation including semen analysis. In a subgroup of 20 men with available data after CS remission, a longitudinal analysis was conducted to assess the reversibility of GA/TF defects.

MAIN RESULTS AND THE ROLE OF CHANCE

Compared to controls, men with CS had significantly lower total testosterone (TT), bioavailable TT, and free TT (P < 0.0001). Hypogonadism, defined as serum TT levels <3.0 ng/ml, was present in 83% of men with EAS, in 61% of men with CD, and in 33% of men with AI-CS. Low-normal LH concentrations in the included men with hypercortisolism indicated HH. Serum sex hormone-binding globulin levels were moderately decreased in men with CD (P = 0.01 vs controls). Among the CS men, those with EAS had significantly lower TT, LH, and FSH levels than those with CD or AI-CS. When compared to controls, patients with EAS were the only group exhibiting a significant decrease in both serum FSH (P = 0.002) and the testicular peptides inhibin B (P < 0.0001) and anti-Müllerian hormone (P = 0.003). Serum INSL3 levels were significantly lower in men with CD than in the controls (P = 0.03). Of note, 24 h-UFC and ACTH were inversely and significantly associated with the majority of reproductive hormones including LH, FSH, TT, and inhibin B. Following successful curative therapy, reproductive assessment at a mean of 6.0 ± 4.3 years showed a significant increase in serum TT (P < 0.0001) and plasma LH (P = 0.02) levels, indicating a reversal of HH in 75% of the affected males. Among the six patients with available semen analysis, the two EAS cases exhibited a decrease in Sertoli cell peptides associated with a severe oligozoospermia, which completely normalized following removal of the source of hypercortisolism.

LIMITATIONS, REASONS FOR CAUTION

The potential bias due to the retrospective design is counteracted by the analysis of the largest male CS cohort to date as well as the use of stringent inclusion and exclusion criteria. Due to the low number of patients with semen analysis in this study, further research is needed to unravel the full spectrum of spermatogenesis defects in men with CS.

WIDER IMPLICATIONS OF THE FINDINGS

This work reveals the variable spectrum of reproductive impact in men with CS. We demonstrate that GA/TF impairment depends on the intensity of hypercortisolism which in turn is related to the underlying etiology. The causal link between hypercortisolism and GA/TF impairment was attested by its reversibility in most patients after CS remission. The wider implications of our findings lie in the potential generalization to a much commoner entity, iatrogenic CS due to chronic exposure to exogenous glucocorticoids.

STUDY FUNDING/COMPETING INTEREST(S)

Several research grants were attributed to J.Y.: (i) a grant from Programme Hospitalier de Recherche Clinique (PHRC # P081212 HYPOPROTEO); (ii) a grant from the French Association of Patients with Adrenal Diseases ('Association surrénales'); and (iii) independent Investigator Research Grants from HRA Pharma, Novartis and Recordati Pharma. A SICPA Foundation grant (Lausanne, Switzerland) allowed protected research time for G.E.P. The above sponsors were not involved in any part of the study. The authors have no competing or other conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Changes in levels of testosterone, insulin sensitivity and metabolic profiles during GnRH therapy: Reciprocity between insulin sensitivity and pituitary responsiveness to GnRH in teenage and young male patients with congenital hypogonadotropic hypogonadism

OBJECTIVES

A direct evaluation of insulin sensitivity on pituitary response to gonadotropin relasing hormone (GnRH) has not been shown in congenital hypogonadotropic hypogonadism (CHH), despite a growing body of evidence in the association of testosterone concentrations with insulin sensitiviy. The objective of the study was to explore whether increased testosterone concentrations in men with CHH improve insulin sensitivity, or vice versa.

DESIGN

A retrospective study at a tertiary centre.

PATIENTS

Series of male CHH patients were included from Jannuary 2014 to December 2019.

MEASUREMENTS

Insulin sensitivity indices calculated from oral glucose tolerance test and steroid hormone levels were examined in 52 patients with newly diagnosed CHH and 22 healthy controls. Thirty-two of the 52 CHH patients received pulsatile GnRH therapy with follow-up every 3-6 months.

RESULTS

Compared to healthy controls, CHH patients had elevated 2 h post-load glucose, HbA1c, fasting insulin, HOMA of insulin resistance (HOMA-IR) and decreased Matsuda index and testosterone (p ≤ .01). The median follow-up for patients (n = 32) who received pulsatile GnRH therapy was 13.5 (11.3-24) months (432 person-months in total). GnRH therapy increased testosterone and Matsuda index (p ≤ .0001), whilst decreased platelet count (p = .04), leptin (p = .04), fasting glucose (p = .01) and HOMA-IR (p &lt; .0001) compared with baseline. The median treatment duration first time to reach the lower limit of normal testosterone concentrations of patients with high and low baseline insulin sensitivity was 15 (95% CI: 8.1-21.9) and 30 months (21.2-38.8), respectively. Correspondingly, after GnRH therapy, luteinizing hormone responsiveness to GnRH provocative test was more vigorous in patients with high insulin sensitivity than those with low insulin sensitivity [17.0 (9.5-25.9) vs. 8.2 (3.3-13.0), p = .01].

CONCLUSION

Pulsatile GnRH therapy elevated testosterone levels in male CHH patients, ameliorated impaired insulin sensitivity and attenuated subclinical inflammatory response, increased insulin sensitivity, in turn, may benefit the efficacy of pulsatile GnRH therapy.

Considerations when treating male pubertal delay pharmacologically

INTRODUCTION

Delayed puberty, defined as the appearance of pubertal signs after the age of 14 years in males, usually affects psychosocial well-being. Patients and their parents show concern about genital development and stature. The condition is transient in most of the patients; nonetheless, the opportunity should not be missed to diagnose an underlying illness.

AREAS COVERED

The aetiologies of pubertal delay in males and their specific pharmacological therapies are discussed in this review.

EXPERT OPINION

High-quality evidence addressing the best pharmacological therapy approach for each aetiology of delayed puberty in males is scarce, and most of the current practice is based on small case series or unpublished experience. Male teenagers seeking attention for pubertal delay most probably benefit from medical treatment to avoid psychosocial distress. While watchful waiting is appropriate in 12- to 14-year-old boys when constitutional delay of growth and puberty (CGDP) is suspected, hormone replacement should not be delayed beyond the age of 14 years in order to avoid impairing height potential and peak bone mass. When primary or central hypogonadism is diagnosed, hormone replacement should be proposed by the age of 12 years provided that a functional central hypogonadism has been ruled out. Testosterone replacement regimens have been used for decades and are fairly standardised. Aromatase inhibitors have arisen as an interesting alternative for boy with CDGP and short stature. Gonadotrophin therapy seems more physiological in patients with central hypogonadism, but its relative efficacy and most adequate timing still need to be established.

Genetics of pubertal delay

The timing of pubertal development is strongly influenced by the genetic background, and clinical presentations of delayed puberty are often found within families with clear patterns of inheritance. The discovery of the underlying genetic regulators of such conditions, in recent years through next generation sequencing, has advanced the understanding of the pathogenesis of disorders of pubertal timing and the potential for genetic testing to assist diagnosis for patients with these conditions. This review covers the significant advances in the understanding of the biological mechanisms of delayed puberty that have occurred in the last two decades.

GnRH replacement rescues cognition in Down syndrome

At the present time, no viable treatment exists for cognitive and olfactory deficits in Down syndrome (DS). We show in a DS model (Ts65Dn mice) that these progressive nonreproductive neurological symptoms closely parallel a postpubertal decrease in hypothalamic as well as extrahypothalamic expression of a master molecule that controls reproduction-gonadotropin-releasing hormone (GnRH)-and appear related to an imbalance in a microRNA-gene network known to regulate GnRH neuron maturation together with altered hippocampal synaptic transmission. Epigenetic, cellular, chemogenetic, and pharmacological interventions that restore physiological GnRH levels abolish olfactory and cognitive defects in Ts65Dn mice, whereas pulsatile GnRH therapy improves cognition and brain connectivity in adult DS patients. GnRH thus plays a crucial role in olfaction and cognition, and pulsatile GnRH therapy holds promise to improve cognitive deficits in DS.

Reproductive Phenotypes in Men With Acquired or Congenital Hypogonadotropic Hypogonadism: A Comparative Study

CONTEXT

In men with congenital hypogonadotropic hypogonadism (CHH), gonadotropin deficiency and testicular impairment exist since fetal development and persist throughout life. In a few reported cases of acquired HH (AHH), HH onset occurs mainly post pubertally.

OBJECTIVE

This work aimed to compare the natural history and reproductive status in large series of CHH and lesional AHH evaluated in a single expert academic center.

METHODS

We included 172 controls, 668 male HH patients (CHH: n = 201 [age 16.9 ± 9.0 years], lesional AHH: n = 467 [age 45.6 ± 18.4 years]) caused by hypothalamic and/or pituitary tumors (mainly adenomas and craniopharyngiomas) or infiltrative/traumatic diseases.

RESULTS

At diagnosis, CHH were significantly younger, with 52.9% diagnosed before age 18 years, compared to only 9.6% of AHH patients. Cryptorchidism (21.9% vs 0.3%) and micropenis were more prevalent in CHH than AHH patients. Low testicular volume (TV) was present in 97% of patients with CHH (mean TV: 3.4 ± 2.7 mL) but in only 30% of those with AHH (mean TV: 20.8 ± 5.0 mL). Whereas no men with persistent CHH had spontaneous fertility, 70.4% of AHH men fathered at least one child without medical therapy. Total testosterone was lower both in CHH and AHH patients than in controls. Compared to controls, circulating gonadotropins and testicular peptides (insulin-like factor-3 and inhibin B) were decreased both in CHH and AHH, but were significantly higher in patients with AHH.

CONCLUSION

In AHH patients, the HH has later onset and is less severe than in CHH and the phenotype can overlap with that of individuals with normal laboratory values. Our data suggest that age at diagnosis is a predictor of the reproductive phenotype in AHH.

Pubertal induction and transition to adult sex hormone replacement in patients with congenital pituitary or gonadal reproductive hormone deficiency: an Endo-ERN clinical practice guideline

An Endo-European Reference Network guideline initiative was launched including 16 clinicians experienced in endocrinology, pediatric and adult and 2 patient representatives. The guideline was endorsed by the European Society for Pediatric Endocrinology, the European Society for Endocrinology and the European Academy of Andrology. The aim was to create practice guidelines for clinical assessment and puberty induction in individuals with congenital pituitary or gonadal hormone deficiency. A systematic literature search was conducted, and the evidence was graded according to the Grading of Recommendations, Assessment, Development and Evaluation system. If the evidence was insufficient or lacking, then the conclusions were based on expert opinion. The guideline includes recommendations for puberty induction with oestrogen or testosterone. Publications on the induction of puberty with follicle-stimulation hormone and human chorionic gonadotrophin in hypogonadotropic hypogonadism are reviewed. Specific issues in individuals with Klinefelter syndrome or androgen insensitivity syndrome are considered. The expert panel recommends that pubertal induction or sex hormone replacement to sustain puberty should be cared for by a multidisciplinary team. Children with a known condition should be followed from the age of 8 years for girls and 9 years for boys. Puberty induction should be individualised but considered at 11 years in girls and 12 years in boys. Psychological aspects of puberty and fertility issues are especially important to address in individuals with sex development disorders or congenital pituitary deficiencies. The transition of these young adults highlights the importance of a multidisciplinary approach, to discuss both medical issues and social and psychological issues that arise in the context of these chronic conditions.

Congenital Micropenis: Etiology And Management

In the newborn, penile length is determined by a number of androgen dependent and independent factors. The current literature suggests that there are interracial differences in stretched penile length in the newborn and although congenital micropenis should be defined as a stretched penile length of less than 2.5 SDS of the mean for the corresponding population and gestation, a pragmatic approach would be to evaluate all boys with a stretched penile length below 2 cm, as congenital micropenis can be a marker for a wide range of endocrine conditions. However, it remains unclear as to whether the state of micropenis, itself, is associated with any long-term consequences. There is a lack of systematic studies comparing the impact of different therapeutic options on long-term outcomes, in terms of genital appearance, quality of life, and sexual satisfaction. To date, research has been hampered by a small sample size and inclusion of a wide range of heterogeneous diagnoses; for these reasons, condition-specific outcomes have been difficult to compare between studies. Lastly, there is a need for a greater collaborative effort in collecting standardized data so that all real-world or experimental interventions performed at an early age can be studied systematically into adulthood.

Insulin-like peptide 3 (INSL3) in congenital hypogonadotrophic hypogonadism (CHH) in boys with delayed puberty and adult men

BACKGROUND

Delayed puberty in males is almost invariably associated with constitutional delay of growth and puberty (CDGP) or congenital hypogonadotrophic hypogonadism (CHH). Establishing the cause at presentation is challenging, with "red flag" features of CHH commonly overlooked. Thus, several markers have been evaluated in both the basal state or after stimulation e.g. with gonadotrophin releasing hormone agonist (GnRHa).Insulin-like peptide 3 (INSL3) is a constitutive secretory product of Leydig cells and thus a possible candidate marker, but there have been limited data examining its role in distinguishing CDGP from CHH. In this manuscript, we assess INSL3 and inhibin B (INB) in two cohorts: 1. Adolescent boys with delayed puberty due to CDGP or CHH and 2. Adult men, both eugonadal and having CHH.

MATERIALS AND METHODS

Retrospective cohort studies of 60 boys with CDGP or CHH, as well as 44 adult men who were either eugonadal or had CHH, in whom INSL3, INB, testosterone and gonadotrophins were measured. Cohort 1: Boys with delayed puberty aged 13-17 years (51 with CDGP and 9 with CHH) who had GnRHa stimulation (subcutaneous triptorelin 100mcg), previously reported with respect to INB. Cohort 2: Adult cohort of 44 men (22 eugonadal men and 22 men with CHH), previously reported with respect to gonadotrophin responses to kisspeptin-54.

RESULTS

Median INSL3 was higher in boys with CDGP than CHH (0.35 vs 0.15 ng/ml; p=0.0002). Similarly, in adult men, median INSL3 was higher in eugonadal men than CHH (1.08 vs 0.05 ng/ml; p<0.0001). However, INSL3 more accurately differentiated CHH in adult men than in boys with delayed puberty (auROC with 95% CI in adult men: 100%, 100-100%; boys with delayed puberty: 86.7%, 77.7-95.7%).Median INB was higher in boys with CDGP than CHH (182 vs 59 pg/ml; p<0.0001). Likewise, in adult men, median INB was higher in eugonadal men than CHH (170 vs 36.5 pg/ml; p<0.0001). INB performed better than INSL3 in differentiating CHH in boys with delayed puberty (auROC 98.5%, 95.9-100%), than in adult men (auROC 93.9%, 87.2-100%).

CONCLUSION

INSL3 better identifies CHH in adult men, whereas INB better identifies CHH in boys with delayed puberty.

Hypothalamo-Pituitary axis and puberty

Puberty is a complex process that culminates in the acquisition of psychophysical maturity and reproductive capacity. This elaborate and fascinating process marks the end of childhood. Behind it lies a complex, genetically mediated neuroendocrine mechanism through which the gonads are activated thanks to the fine balance between central inhibitory and stimulating neuromodulators and hormones with both central and peripheral action. The onset of puberty involves the reactivation of the hypothalamic-pituitary-gonadal (HPG) axis, supported by the initial "kiss" between kisspeptin and the hypothalamic neurons that secrete GnRH (the GnRH "pulse generator"). This pulsatile production of GnRH is followed by a rise in LH and, consequently, in gonadal steroids. The onset of puberty varies naturally between individuals, and especially between males and females, in the latter of whom it is typically earlier. However, pathological variations, namely precocious and delayed puberty, are also possible. This article reviews the scientific literature on the physiological mechanisms of puberty and the main pathophysiological aspects of its onset.