Androgens During Infancy, Childhood, and Adolescence: Physiology and Use in Clinical Practice

Hormone Therapy During Infancy or Early Childhood for Patients with Hypogonadotropic Hypogonadism, Klinefelter or Turner Syndrome: Has the Time Come?

Managing patients unable to produce sex steroids using gonadotropins to mimic minipuberty in hypogonadotropic hypogonadism, or sex steroids in patients with Klinefelter or Turner syndrome, is promising. There is a need to pursue research in this area, with large prospective cohorts and long-term data before these treatments can be routinely considered.

Pituitary gland height evaluated with magnetic resonance imaging in premature twins: the impact of growth and sex

BACKGROUND

Pituitary gland height reflects secretory activity of the hypothalamo-pituitary axis.

OBJECTIVE

To assess the cumulative impact of fetal growth and sex on pituitary gland height in premature twins, dissociated from prematurity.

MATERIALS AND METHODS

A retrospective study was conducted, assessing the pituitary gland height in 63 pairs of preterm twins, measured from T1-weighted magnetic resonance imaging (MRI). Auxological parameters, including body weight, body length, and head circumference, at birth and at the time of MRI, were used as proxies for fetal and postnatal growth, respectively. The study population was divided into two groups, using corrected age at around term equivalent as the cutoff point. Statistical analysis was performed using mixed-effects linear regression models.

RESULTS

When pituitary gland height was evaluated at around term equivalent, a greater pituitary gland height, suggesting a more immature hypothamo-pituitary axis, was associated with the twin exhibiting lower auxological data at birth. The same association was observed when body weight and length at MRI were used as covariants. In the group evaluated after term equivalent, a smaller pituitary gland height, suggesting a more mature hypothamo-pituitary axis, was associated with male sex. This difference was observed in twin pairs with higher average body weight at birth, and in babies exhibiting higher auxological data at MRI.

CONCLUSION

After isolating the effect of prematurity, at around term equivalent, pituitary gland height reflects the cumulative impact of fetal growth on the hypothalamo-pituitary axis. Subsequently, pituitary gland height shows effects of sex and of fetal and postnatal growth.

Klinefelter Syndrome: A Genetic Disorder Leading to Neuroendocrine Modifications and Psychopathological Vulnerabilities in Children-A Literature Review and Case Report

Klinefelter syndrome (KS), characterized by an additional X-chromosome in males, manifests in a wide range of neuroendocrine and psychiatric symptoms. Individuals with KS often face increased risks of hormonal dysfunction, leading to depression and anxiety, although extended research during pediatric and adolescent age is still limited. This critical phase, decisive for KS children, is influenced by a combination of genetic, environmental and familial factors, which impact brain plasticity. In this report, we reviewed, in a narrative form, the crucial KS psychopathological hallmarks in children. To better describe neuroendocrine and neuropsychiatric outcomes in children with KS, we presented the case of an 11-year-old prepubertal child with mosaic KS who was referred to our Center of Developmental Psychopathology due to a decline in his academic performance, excessive daytime fatigue and increased distractibility over the past few months. Family history revealed psychiatric conditions among first- and second-degree relatives, including recently divorced parents and a 15-year-old sister. Early-onset persistent depressive disorder and anxious traits were diagnosed. Timely identification of susceptible children, with thorough examination of familial psychiatric history, environmental influences and neurocognitive profile, alongside targeted interventions, could potentially mitigate lifelong psychopathology-related disabilities in pediatric and adolescent KS cases, including those with mosaic KS.

Association between sex hormones and bone age in boys aged 9-18 years from China

This study aimed to analyse the association between sex hormones and bone age (BA) in boys aged 9-18 years, both individually and interactively, and further to explore whether nutritional status may influence this association. A retrospective analysis was performed among 1382 Chinese boys with physical measurements, sexual characteristics, BA radiographs and sex hormone indicators from February 2015 to February 2022. A total of 470 (34.0%) boys had advanced BA. BA was positively associated with estradiol, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone in both advanced and normal BA groups after adjusting for age, genetic height and body mass index. Multiple logistic regression showed that after adjusting for covariates, estradiol (odds ratio [OR] = 1.66, 95% confidence interval [CI]: 1.14-2.12), LH (OR = 1.43, 95% CI: 1.04-1.96), and testosterone (OR = 1.58, 95% CI: 1.17-2.13) were significantly associated with the increased risk of advanced BA in boys, and the association was reinforced when these hormones were interactively explored. Stratified by nutritional status, the interaction between estradiol, LH, and testosterone showed a strong association with advanced BA in boys with normal weight.

Clinical, Ovulatory and Histological Effect of a Postnatal Testosterone Treatment in Female Dogs

It has been described in some female mammalian species that postnatal androgenization causes reproductive structural and functional abnormalities. The objective of this study was to describe the clinical, ovulatory and genital effects of postnatal androgens in female dogs. Ten newborn female crossbred puppies were randomly assigned to: testosterone enanthate 18 mg/100 g sc (TE; n = 5) or placebo sc (PL; n = 5). The puppies were physically followed up until puberty when ovulation was tested by serum progesterone. Then, ovariohysterectomies were performed, and genital tracts were grossly and histomorphometrically examined. At puberty, all the females had normal estrous behavior and ovulated without age and body weight differences. All TE puppies presented mild clitoris enlargement. Gross and microscopical ovarian examination did not reveal differences. Conversely, the endometrial area occupied by uterine glands as well as the height of the glandular and luminal epithelium were higher in the TE than in the PL group (<0.01). The height of the endometrium and myometrial thickness did not differ between groups. It was concluded that a supraphysiological postnatal dose of testosterone did not affect ovulatory capacity, nor did it provoke gonadal histological alterations, although it caused an increased area of endometrial glands and a higher uterine epithelium.

Streamlined identification of clinically and functionally relevant genetic regulators of lower-tract urogenital development

Congenital anomalies of the lower genitourinary (LGU) tract are frequently comorbid due to genetically linked developmental pathways, and are among the most common yet most socially stigmatized congenital phenotypes. Genes involved in sexual differentiation are prime candidates for developmental anomalies of multiple LGU organs, but insufficient prospective screening tools have prevented the rapid identification of causative genes. Androgen signaling is among the most influential modulators of LGU development. The present study uses SpDamID technology in vivo to generate a comprehensive map of the pathways actively regulated by the androgen receptor (AR) in the genitalia in the presence of the p300 coactivator, identifying wingless/integrated (WNT) signaling as a highly enriched AR-regulated pathway in the genitalia. Transcription factor (TF) hits were then assayed for sexually dimorphic expression at two critical time points and also cross-referenced to a database of clinically relevant copy number variations to identify 252 TFs exhibiting copy variation in patients with LGU phenotypes. A subset of 54 TFs was identified for which LGU phenotypes are statistically overrepresented as a proportion of total observed phenotypes. The 252 TF hitlist was then subjected to a functional screen to identify hits whose silencing affects genital mesenchymal growth rates. Overlap of these datasets results in a refined list of 133 TFs of both functional and clinical relevance to LGU development, 31 of which are top priority candidates, including the well-documented renal progenitor regulator, Sall1. Loss of Sall1 was examined in vivo and confirmed to be a powerful regulator of LGU development.

Fibrous Dysplasia Masquerading as Sternal Malignancy: A Rare and Challenging Presentation

This case report presents a rare and challenging manifestation of polyostotic fibrous dysplasia (FD), a skeletal developmental anomaly characterized by the proliferation of fibrous connective tissue intermingled with irregular bony trabeculae. While monostotic FD is more common, polyostotic FD can occur in the context of McCune-Albright syndrome, a multisystem developmental disorder. Our patient, a 55-year-old female with a history of diabetes, hypothyroidism, and dyslipidemia, presented with progressively worsening dysphagia, sternal pain, and swelling over three years. Clinical examination revealed a tender and hard swelling in the upper sternal area, prompting further evaluation. Laboratory results, including bone turnover markers, were unremarkable. Imaging studies unveiled a sizable anterior mediastinal lesion with heterogeneous enhancement and coarse calcifications, initially raising concerns of malignancy. Subsequent positron emission tomography scan findings confirmed FD involvement in both the sternum and right femur. Histopathology of the mediastinal mass revealed a spindle cell neoplasm with bony metaplasia, consistent with FD, supported by immunohistochemistry. A multidisciplinary team affirmed the diagnosis of polyostotic FD, and follow-up imaging after one year demonstrated no significant change in lesion size, confirming a benign etiology. While bisphosphonate therapy was planned, regrettably, the patient was lost to follow-up. This case underscores the importance of a comprehensive, multidisciplinary approach in diagnosing and managing complex presentations of FD, ultimately contributing to improved patient care and outcomes in such instances.

The Menopausal Transition: Is the Hair Follicle "Going through Menopause"?

This article explores the link between menopause and changes in the hair follicle (HF) lifecycle, focusing on hormonal and metabolic dynamics. During menopause, hormonal fluctuations and aging can impact the HF, leading to phenomena such as thinning, loss of volume, and changes in hair texture. These changes are primarily attributed to a decrease in estrogen levels. However, not all women experience significant hair changes during menopause, and the extent of transformations can vary considerably from person to person, influenced by genetic factors, stress, diet, and other elements. Furthermore, menopause mirrors the aging process, affecting metabolism and blood flow to the HFs, influencing the availability of vital nutrients. The article also discusses the key role of energy metabolism in the HF lifecycle and the effect of hormones, particularly estrogens, on metabolic efficiency. The concept of a possible "menopause" clinically independent of menopause is introduced, related to changes in HF metabolism, emphasizing the importance of individual factors such as estrogen receptor responses, genetics, and last but not least, the microbiota in determining these dynamics.

The effect of testosterone treatment on bone mineral density in Klinefelter syndrome: A retrospective cohort study

BACKGROUND

Although Klinefelter syndrome (KS) is the most frequent sex-hormone disorder, there is ongoing uncertainty about the often associated sex-hormone deficiency, its impact on common comorbidities, and therefore about prevention and treatment. In this study, we focus on bone loss, reported to occur in over 40% of KS patients, and the impact of testosterone replacement therapy (TRT) on this comorbidity.

OBJECTIVES

This single-center retrospective cohort study in a tertiary hospital compared the effect of treatment with TRT to no TRT on evolution of bone mineral density (BMD) in KS patients.

METHODS

After a medical chart review, a total of 52 KS subjects were included in this study. BMD was measured by dual-energy X-ray absorptiometry (DXA) and expressed as T-scores.

RESULTS

The subjects were divided into three groups, according to TRT. In the subgroup that only started TRT after baseline measurements (mean age 31 years), we observed significant gain in BMD T-score at the lumbar spine (0.58 ± 0.60, p = 0.003; mean gain of 0.62% areal BMD per year) and total femur T-score (0.24 ± 0.39, p = 0.041; mean gain of 0.25% areal BMD per year) after a mean follow-up period of 7.5 years. Compared to untreated subjects, a significant difference in evolution was demonstrated at the lumbar level (+0.58 ± 0.60 vs. -0.14 ± 0.42, p = 0.007). In untreated subjects with normal testosterone levels, a loss of BMD (-0.27 ± 0.37, p = 0.029; mean loss of 0.49% areal BMD per year) at the femoral neck was measured. This decline was equal to the predicted loss seen in the general male population.

CONCLUSION

TRT results in BMD gain in patients with KS with testosterone deficiency, mainly at the lumbar spine. However, this effect is limited (0.62% per year). Patients who were not treated with TRT because of sufficient endogenous testosterone levels, showed only the predicted age-related bone loss during follow-up. The need for TRT in maintaining bone health in KS should be evaluated on an individual basis according to the degree of sex steroid deficiency.

Allometric Scaling of Testosterone Enanthate Pharmacokinetics to Adolescent Hypogonadal Males (IM and SC Administration)

Context

Intramuscular (IM) testosterone enanthate (TE) and testosterone pellets were US Food and Drug Administration approved before 1962 for pediatric use but not studied in controlled trials in adolescents.

Objective

An analysis using nonlinear mixed effect (NLME) modeling was designed to evaluate the adult pharmacokinetics (PK) of subcutaneous (SC) and IM TE. This model was used to simulate SC and IM TE administration in adolescents of different weight groups.

Methods

Data from adult male patients in a phase 2 trial were used to characterize the PK of TE using population PK modeling for SC and IM administration: Allometry was used to scale PK parameters from the adult model to simulate adolescent (aged 12 to < 18 years) serum testosterone levels at body weights of 30, 40, 50, and 60 kg after weekly, every-other-week (EOW), and monthly SC and IM administration of 12.5, 25, 50, 75, and 100 mg TE regimens.

Results

The final data set included 714 samples from 15 patients receiving 100 mg SC TE and 123 samples from 10 patients receiving 200 mg IM TE. In simulated populations, average serum concentration SC:IM ratios were 0.783, 0.776, and 0.757 at steady state for weekly, EOW, and monthly dosing groups, respectively. Simulated regimens of 12.5 mg SC TE monthly produced serum testosterone levels representative of early puberty and simulated pubertal stage progression following multiple subsequent testosterone dose increases.

Conclusion

SC TE administration achieved a testosterone exposure-response relationship similar to IM TE in simulated adolescent hypogonadal males, which may reduce size of fluctuations in serum T and related symptoms.

Independent and combined associations of urinary arsenic exposure and serum sex steroid hormones among 6-19-year old children and adolescents in NHANES 2013-2016

Arsenic exposure may disrupt sex steroid hormones, causing endocrine disruption. However, human evidence is limited and inconsistent, especially for children and adolescents. To evaluate the independent and combined associations between arsenic exposure and serum sex steroid hormones in children and adolescents, we conducted a cross-sectional analysis of data from 1063 participants aged 6 to 19 years from the 2013-2016 National Health and Nutrition Examination Survey (NHANES). Three urine arsenic metabolites were examined, as well as three serum sex steroid hormones, estradiol (E₂), total testosterone (TT), and sex hormone-binding globulin (SHBG). The ratio of TT to E₂ (TT/E₂) and the free androgen index (FAI) generated by TT/SHBG were also assessed. Linear regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) were used to evaluate the associations of individual or arsenic metabolite combinations with sex steroid hormones by gender and age stratification. Positive associations were found between total arsenic and arsenic metabolites with TT, E₂, and FAI. In contrast, negative associations were found between arsenic metabolites and SHBG. Furthermore, there was an interaction after gender-age stratification between DMA and SHBG in female adolescents. Notably, based on the WQS and BKMR model results, the combined association of arsenic and its metabolites was positively associated with TT, E₂, and FAI and negatively associated with SHBG. Moreover, DMA and MMA dominated the highest weights among the arsenic metabolites. Overall, our results indicate that exposure to arsenic, either alone or in mixtures, may alter sex steroid hormone levels in children and adolescents.

Prenatal diagnosis of sex chromosome aneuploidy-What do we tell the prospective parents?

Sex chromosome aneuploidy (SCA) can be detected on prenatal diagnostic testing and cell free DNA screening (cfDNA). High risk cfDNA results should be confirmed with diagnostic testing. This summary article serves as an update for prenatal providers and assimilates data from neurodevelopmental, epidemiologic, and registry studies on the most common SCA. This information can be helpful for counseling after prenatal diagnosis of sex chromosome aneuploidy. Incidence estimates may be influenced by ascertainment bias and this article is not a substitute for interdisciplinary consultation and counseling.

Effects of Hormones and Endocrine Disorders on Hair Growth

Hormones have a close association with hair growth; thus, they have a big impact on the hair cycle and hair follicle structure. Many hormones control hair growth, cycle, and density. Hair abnormalities are frequent in therapeutic practice, and they can cause severe emotional discomfort depending on societal and ethnic standards. As a result, disorders that impact the endocrine system can induce a variety of physiological hair growth and cycling alterations. Hirsutism and patterned hair loss have a significant impact on human personality. These illnesses necessitate a comprehensive approach to diagnosis and treatment. The hormonal impact on hair growth and the association of different endocrine disorders with hair changes are briefly discussed here.

Efficacy of short-term induction therapy with low-dose testosterone as a diagnostic tool in the workup of delayed growth and puberty in boys

PURPOSE

Constitutional delay of growth and puberty (CDGP) represents the most frequent cause of delayed puberty in males, sharing some clinical features with growth hormone deficiency (GHD) and isolated hypogonadotropic hypogonadism (IHH). Short-term induction therapy (SIT) has been approved for the induction of puberty in CDGP. We aim to investigate the efficacy of SIT with transcutaneous testosterone gel (TTG) or intramuscular testosterone therapy (IMTT) in a cohort of CDGP subjects, compared to clinical observation. Furthermore, we aim to evaluate the role of SIT as a diagnostic tool to differentiate CDGP from GHD and IHH subjects.

METHODS

The retrospective study included 246 male subjects with delayed puberty. The study population was divided into three groups: TTG, IMTT, and control group (CNT).

RESULTS

At 6 months observation, height velocity (HV) was significantly increased in both treated groups compared to CNT group, particularly higher in TTG than IMTT group. A significant testicular enlargement was revealed in both CNT and TTG group compared to IMTT group. Furthermore, LH value was significantly greater in TTG compared to IMTT group. IGF-1 values after SIT rose significantly in both treated groups compared to CNT group. Moreover, almost all GH provocative tests performed after SIT showed a normal GH response.

CONCLUSION

SIT with TTG appears to be more effective to induce growth spurt, better tolerated and with a more physiological effect on pubertal induction compared to IMTT in CDGP population. Finally, TTG might be a useful tool in the diagnostic work up to discriminate CDGP from GHD or IHH.

New and Consolidated Therapeutic Options for Pubertal Induction in Hypogonadism: In-depth Review of the Literature

Delayed puberty (DP) defines a retardation of onset/progression of sexual maturation beyond the expected age from either a lack/delay of the hypothalamo-pituitary-gonadal axis activation or a gonadal failure. DP usually gives rise to concern and uncertainty in patients and their families, potentially affecting their immediate psychosocial well-being and also creating longer term psychosexual sequelae. The most frequent form of DP in younger teenagers is self-limiting and may not need any intervention. Conversely, DP from hypogonadism requires prompt and specific treatment that we summarize in this review. Hormone therapy primarily targets genital maturation, development of secondary sexual characteristics, and the achievement of target height in line with genetic potential, but other key standards of care include body composition and bone mass. Finally, pubertal induction should promote psychosexual development and mitigate both short- and long-term impairments comprising low self-esteem, social withdrawal, depression, and psychosexual difficulties. Different therapeutic options for pubertal induction have been described for both males and females, but we lack the necessary larger randomized trials to define the best approaches for both sexes. We provide an in-depth and updated literature review regarding therapeutic options for inducing puberty in males and females, particularly focusing on recent therapeutic refinements that better encompass the heterogeneity of this population, and underlining key differences in therapeutic timing and goals. We also highlight persistent shortcomings in clinical practice, wherein strategies directed at "the child with delayed puberty of uncertain etiology" risk being misapplied to older adolescents likely to have permanent hypogonadism.

Defining the role of pre-operative hormonal therapy in hypospadias

In hypospadias surgery, pre-operative hormonal therapy (PHT) is primarily used to increase penile dimensions and the vascularity of tissues available for reconstruction, but its use is non-uniform in clinical practice, with no consensus on application or utility. This review aims to summarise: (i) the penile tissue response to hormone therapy, (ii) its impact on hypospadias surgery outcomes, and (iii) the endocrinological considerations and sequelae. PHT is more often indicated for complex cases such as proximal hypospadias, hypospadias with microphallus and hypospadias reoperations. While PHT has clear effects on penile morphometry, and more recent controlled trials suggest improved surgical outcomes, the lack of consistent outcome definitions and generally inadequate follow-up periods continue to consign many of the potential long-term effects of PHT to the unknown. There is currently insufficient robust evidence to allow a clinical guideline to be constructed. The need for a well-powered multi-centre prospective randomised trial to address this question is evident but awaits a unified consensus on issues surrounding the understanding of aetiology, classification of hypospadias morphology, definition of important prognostic variables and uniform application of outcome measures. The effects of PHT may be utilised to improve outcomes in cases of proximal and severe hypospadias, which under the current paradigm represent a significant surgical challenge.

Androgens and male sexual function

Sexual symptoms are the most specific determinants of low testosterone (T) observed during adulthood. In this narrative review, we summarize the most important evidence supporting the positive relationships between endogenous T levels and sexual activity in the adult male, by using preclinical and clinical observations. In addition, we also report an update of our previous meta-analysis evaluating the effects of T treatment (TRT) on sexual functioning in subjects with T deficiency. Available data indicate that TRT of symptomatic hypogonadal men can improve several aspects of sexual life, including erection. However, the effect is rather modest and lower in subjects with associated metabolic conditions. The specific observed effects are similar to those derived from lifestyle intervention. Since TRT might result in body composition improvement, it is reasonable to suppose that an initial treatment with T can improve the willingness of hypogonadal subjects to perform physical exercise and to adhere to a healthier behavior. Similar data were derived from animal models. However, it should be important to recognize that lifestyle modifications should be the first step to promote weigh reduction. TRT can be combined with lifestyle interventions only in symptomatic hypogonadal subjects especially in the presence of comorbid metabolic conditions.

Puberty Induction in Adolescent Males: Current Practice

Puberty is a developmental stage characterized by the appearance of secondary sexual characteristics which leads to complete physical, psychosocial, and sexual maturation. The current practice of hormonal therapy to induce puberty in adolescent males is based on published consensus and expert opinion. Evidence-based guidelines on optimal timing and regimen in puberty induction in males are lacking, and this reflects some discrepancies in practice among endocrinologists. It is worth mentioning that the availability of various hormonal products in markets, their different routes of administration, and patients/parents’ preference also have an impact on clinical decisions. This review outlines the current clinical approach to delayed puberty in boys with an emphasis on puberty induction.

Good Clinical Practice of the Italian Society of Thalassemia and Haemoglobinopathies (SITE) for the Management of Endocrine Complications in Patients with Haemoglobinopathies

Background: The treatment of endocrinopathies in haemoglobinopathies is a continually expanding research area; therefore, recommendations supporting the appropriateness of treatments are a pressing need for the medical community. Methods: The Management Committee of SITE selected and gathered a multidisciplinary and multi-professional team, including experts in haemoglobinopathies and experts in endocrinopathies, who have been flanked by experts with methodological and organizational expertise, in order to formulate recommendations based on the available scientific evidence integrated by personal clinical experience. The project followed the systematic approach for the production of clinical practice guidelines according to the methodology suggested by the National Center for Clinical Excellence, Quality and Safety of Care (CNEC). Results: Out of 14 topics, 100 clinical questions were addressed, and 206 recommendations were elaborated on. The strength of recommendations, panel agreement, a short general description of the topic, and the interpretation of evidence were reported. Conclusions: Good Practice Recommendations are the final outcome of translational research and allow one to transfer to the daily clinical practice of endocrine complications in haemoglobinopathies.

Testosterone therapy in children and adolescents: to whom, how, when?

Male production of testosterone is crucial for the development of a wide range of functions. External and internal genitalia formation, secondary sexual characteristics, spermatogenesis, growth velocity, bone mass density, psychosocial maturation, and metabolic and cardiovascular profiles are closely dependent on testosterone exposure. Disorders in androgen production can present during all life-stages, including childhood and adolescence, and testosterone therapy (TT) is in many cases the only treatment that can correct the underlying deficit. TT is controversial in the pediatric population as hypoandrogenism is difficult to classify and diagnose in these age groups, and standardized protocols of treatment and monitorization are still lacking. In pediatric patients, hypogonadism can be central, primary, or a combination of both. Testosterone preparations are typically designed for adults' TT, and providers need to be aware of the advantages and disadvantages of these formulations, especially cognizant of supratherapeutic dosing. Monitoring of testosterone levels in boys on TT should be tailored to the individual patient and based on the anticipated duration of therapy. Although clinical consensus is lacking, an approximation of the current challenges and common practices in pediatric hypoandrogenism could help elucidate the broad spectrum of pathologies that lie behind this single hormone deficiency with wide-ranging implications.

Recent advancement in the treatment of boys and adolescents with hypogonadism

Clinical manifestations and the need for treatment varies according to age in males with hypogonadism. Early foetal-onset hypogonadism results in disorders of sex development (DSD) presenting with undervirilised genitalia whereas hypogonadism established later in foetal life presents with micropenis, cryptorchidism and/or micro-orchidism. After the period of neonatal activation of the gonadal axis has waned, the diagnosis of hypogonadism is challenging because androgen deficiency is not apparent until the age of puberty. Then, the differential diagnosis between constitutional delay of puberty and central hypogonadism may be difficult. During infancy and childhood, treatment is usually sought because of micropenis and/or cryptorchidism, whereas lack of pubertal development and relative short stature are the main complaints in teenagers. Testosterone therapy has been the standard, although off-label, in the vast majority of cases. However, more recently alternative therapies have been tested: aromatase inhibitors to induce the hypothalamic-pituitary-testicular axis in boys with constitutional delay of puberty and replacement with GnRH or gonadotrophins in those with central hypogonadism. Furthermore, follicle-stimulating hormone (FSH) priming prior to hCG or luteinizing hormone (LH) treatment seems effective to induce an enhanced testicular enlargement. Although the rationale for gonadotrophin or GnRH treatment is based on mimicking normal physiology, long-term results are still needed to assess their impact on adult fertility.

Sex is a defining feature of neuroimaging phenotypes in major brain disorders

Sex is a biological variable that contributes to individual variability in brain structure and behavior. Neuroimaging studies of population-based samples have identified normative differences in brain structure between males and females, many of which are exacerbated in psychiatric and neurological conditions. Still, sex differences in MRI outcomes are understudied, particularly in clinical samples with known sex differences in disease risk, prevalence, and expression of clinical symptoms. Here we review the existing literature on sex differences in adult brain structure in normative samples and in 14 distinct psychiatric and neurological disorders. We discuss commonalities and sources of variance in study designs, analysis procedures, disease subtype effects, and the impact of these factors on MRI interpretation. Lastly, we identify key problems in the neuroimaging literature on sex differences and offer potential recommendations to address current barriers and optimize rigor and reproducibility. In particular, we emphasize the importance of large-scale neuroimaging initiatives such as the Enhancing NeuroImaging Genetics through Meta-Analyses consortium, the UK Biobank, Human Connectome Project, and others to provide unprecedented power to evaluate sex-specific phenotypes in major brain diseases.

Society for Endocrinology UK Guidance on the initial evaluation of a suspected difference or disorder of sex development (Revised 2021)

It is paramount that any child or adolescent with a suspected difference or disorder of sex development (DSD) is assessed by an experienced clinician with adequate knowledge about the range of conditions associated with DSD and is discussed with the regional DSD service. In most cases, the paediatric endocrinologist within this service acts as the first point of contact but involvement of the regional multidisciplinary service will also ensure prompt access to specialist psychology and nursing care. The underlying pathophysiology of DSD and the process of delineating this should be discussed with the parents and affected young person with all diagnostic tests undertaken in a timely fashion. Finally, for rare conditions such as these, it is imperative that clinical experience is shared through national and international clinical and research collaborations.

The Evidence for Fertility Preservation in Pediatric Klinefelter Syndrome

Klinefelter syndrome (KS) is a common cause of non-obstructive azoospermia (NOA). Advances in fertility preservation (FP) techniques, such as the use of microdissection testicular sperm extraction (micro-TESE), have improved sperm retrieval rates (SRR) up to 40–50% in this population. Age has been suggested to have an impact on FP, postulating that sperm production may deteriorate over time due to germ cell loss. As such, sperm retrieval for patients with KS at a younger age has been proposed to further improve SRR; however, whether such practice pragmatically improves SRR is yet to be determined, and controversy remains with concerns over trauma caused by FP procedures on further impairment of testicular function. There has also been a debate on the ethics of performing FP procedures in the pediatric population. Optimizing FP for patients with KS invariably requires a holistic multidisciplinary approach. This review aimed to evaluate the latest evidence in performing FP in pediatric patients with KS, and discuss the controversy surrounding such practice. Hormonal changes in patients with KS during childhood and the use of hormonal manipulation to optimize SSR in this population have also been reviewed.

Generation of two human induced pluripotent stem cell lines from a patient with complete androgen insensitivity syndrome with a hemizygous single nucleotide variant in the androgen receptor (AR) gene

Complete Androgen Insensitivity Syndrome (CAIS) is a difference of sex development (DSD) caused by loss of function of the androgen receptor (AR) gene. Patients typically identify as female and have a 46,XY karyotype. Two induced pluripotent stem cell lines (iPSCs), LCHi001-A and LCHi001-B, were generated from a participant with CAIS with AR mutation: c.2698A>T (p.Ile900Phe). Both lines presented typical morphology, expressed stem cell markers, differentiated into three germ layers, had a normal 46,XY karyotype, were mycoplasma-free, and carried the expected mutation in AR. These iPSC lines are an important resource for studying CAIS pathogenesis and possible treatment options.

Adjusting for Pubertal Status Reduces Overweight and Obesity Prevalence in the United States

OBJECTIVE

To compare pediatric overweight and obesity prevalence among non-Hispanic white, Mexican American, and non-Hispanic black US youths before and after adjusting body mass index (BMI) for pubertal status, as assessed by Tanner stage.

STUDY DESIGN

We analyzed cross-sectional anthropometric and pubertal data from non-Hispanic white, Mexican American, and non-Hispanic black youths in the National Health and Nutrition Examination Survey (NHANES) III. We developed specialized Tanner stage and chronological age-adjusted models to establish Tanner-stage adjusted BMI z-scores, which were then used to determine adjusted overweight/obesity prevalence. We compared pediatric overweight/obesity prevalence before and after pubertal status adjustment.

RESULTS

Among 3206 youths aged 8-18 years (50% male; 26% non-Hispanic white, 35% Mexican American, 39% non-Hispanic black), adjusting BMI for Tanner stage significantly reduced overweight (males, from 29% to 21%; females, from 29% to 17%) and obesity (males, from 14% to 7%; females, from 11% to 5%) prevalence across all races/ethnicities. The obesity prevalence reduction was more pronounced in Mexican Americans (males, 11% reduction; females, 9% reduction) and non-Hispanic blacks (males and females, 10% reduction) compared with non-Hispanic whites (males, 6% reduction; females, 5% reduction). Similar patterns were seen in overweight prevalence.

CONCLUSIONS

Adjusting for pubertal status reduced the prevalence of overweight/obesity in non-Hispanic white, Mexican American, and non-Hispanic black youth. This suggests that adjusting for puberty incorporates changes otherwise not captured when only considering the age of a child. Adjusting BMI for pubertal status may be important when interpreting a youth's weight status and consideration for obesity management, as well as when interpreting pediatric overweight/obesity prevalence data.

Prader-Willi Syndrome and Hypogonadism: A Review Article

Prader-Labhart-Willi syndrome (PWS) is a rare genetic disorder characterized by intellectual disability, behavioural problems, hypothalamic dysfunction and specific dysmorphisms. Hypothalamic dysfunction causes dysregulation of energy balance and endocrine deficiencies, including hypogonadism. Although hypogonadism is prevalent in males and females with PWS, knowledge about this condition is limited. In this review, we outline the current knowledge on the clinical, biochemical, genetic and histological features of hypogonadism in PWS and its treatment. This was based on current literature and the proceedings and outcomes of the International PWS annual conference held in November 2019. We also present our expert opinion regarding the diagnosis, treatment, care and counselling of children and adults with PWS-associated hypogonadism. Finally, we highlight additional areas of interest related to this topic and make recommendations for future studies.

Testosterone Use in Adolescent Males: Current Practice and Unmet Needs

Testosterone replacement therapy (TRT) is routinely prescribed in adolescent males with constitutional delay of growth and puberty (CDGP) or hypogonadism. With many new testosterone (T) formulations entering the market targeted for adults, we review current evidence and TRT options for adolescents and identify areas of unmet needs. We searched PubMed for articles (in English) on testosterone therapy, androgens, adolescence, and puberty in humans. The results indicate that short-term use of  T enanthate (TE) or oral  T undecanoate is safe and effective in inducing puberty and increasing growth in males with CDGP. Reassuring evidence is emerging on the use of transdermal  T to induce and maintain puberty. The long-term safety and efficacy of TRT for puberty completion and maintenance have not been established. Current  TRT regimens are based on consensus and expert opinion, but evidence-based guidelines are lacking. Limited guidance exists on when and how  T should be administered and optimal strategies for monitoring therapy once it is initiated. Only  TE and  T pellets are US Food and Drug Administration approved for use in adolescent males in the United States. Despite the introduction of a wide variety of new  T formulations, they are designed for adults, and their metered doses are difficult to titrate in adolescents. In conclusion, TRT in adolescent males is hindered by lack of long-term safety and efficacy data and limited options approved for use in this population. Additional research is needed to identify the route, dose, duration, and optimal timing for TRT in adolescents requiring androgen therapy.

Testosterone Therapy and Its Monitoring in Adolescent Boys with Hypogonadism: Results of an International Survey from the I-DSD Registry

It is unclear whether testosterone replacement therapy (TRT) in adolescent boys, affected by a range of endocrine diseases that may be associated with hypogonadism, is particularly common. The aim of this study was to assess the contemporary practice of TRT in boys included in the I-DSD Registry. All participating centres in the I-DSD Registry that had boys between 10 and 18 years of age and with a condition that could be associated with hypogonadism were invited to provide further information in 2019. Information on 162 boys was collected from 15 centres that had a median (range) number of 6 boys per centre (1.35). Of these, 30 (19%) from 9 centres were receiving TRT and the median (range) age at the start was 12.6 years (10.8-16.2), with 6 boys (20%) starting at <12 years. Median (range) age of boys not on TRT was 11.7 years (10.7-17.7), and 69 out of 132 (52%) were <12 years. TRT had been initiated in 20 of 71 (28%) boys with a disorder of gonadal development, 3 of 14 (21%) with a disorder of androgen synthesis, and all 7 (100%) boys with hypogonadotropic hypogonadism. The remainder who did not have TRT included 15 boys with partial androgen insensitivity, 52 with non-specific XY DSD, and 3 with persistent Müllerian duct syndrome. Before starting TRT, liver function and blood count were checked in 19 (68%) and 18 boys (64%), respectively, a bone age assessment was performed in 23 (82%) and bone mineral density assessment in 12 boys (43%). This snapshot of contemporary practice reveals that TRT in boys included in the I-DSD Registry is not very common, whilst the variation in starting and monitoring therapy is quite marked. Standardisation of practice may lead to more effective assessment of treatment outcomes.

Evidence Limitations in Determining Sexually Dimorphic Outcomes in Pediatric Post-Traumatic Hypopituitarism and the Path Forward

Neuroendocrine dysfunction can occur as a consequence of traumatic brain injury (TBI), and disruptions to the hypothalamic-pituitary axis can be especially consequential to children. The purpose of our review is to summarize current literature relevant to studying sex differences in pediatric post-traumatic hypopituitarism (PTHP). Our understanding of incidence, time course, and impact is constrained by studies which are primarily small, are disadvantaged by significant methodological challenges, and have investigated limited temporal windows. Because hormonal changes underpin the basis of growth and development, the timing of injury and PTHP testing with respect to pubertal stage gains particular importance. Reciprocal relationships among neuroendocrine function, TBI, adverse childhood events, and physiological, psychological and cognitive sequelae are underconsidered influencers of sexually dimorphic outcomes. In light of the tremendous heterogeneity in this body of literature, we conclude with the common path upon which we must collectively arrive in order to make progress in understanding PTHP.

European academy of andrology guidelines on Klinefelter Syndrome Endorsing Organization: European Society of Endocrinology

BACKGROUND

Knowledge about Klinefelter syndrome (KS) has increased substantially since its first description almost 80 years ago. A variety of treatment options concerning the spectrum of symptoms associated with KS exists, also regarding aspects beyond testicular dysfunction. Nevertheless, the diagnostic rate is still low in relation to prevalence and no international guidelines are available for KS.

OBJECTIVE

To create the first European Academy of Andrology (EAA) guidelines on KS.

METHODS

An expert group of academicians appointed by the EAA generated a consensus guideline according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system.

RESULTS

Clinical features are highly variable among patients with KS, although common characteristics are severely attenuated spermatogenesis and Leydig cell impairment, resulting in azoospermia and hypergonadotropic hypogonadism. In addition, various manifestations of neurocognitive and psychosocial phenotypes have been described as well as an increased prevalence of adverse cardiovascular, metabolic and bone-related conditions which might explain the increased morbidity/mortality in KS. Moreover, compared to the general male population, a higher prevalence of dental, coagulation and autoimmune disorders is likely to exist in patients with KS. Both genetic and epigenetic effects due to the supernumerary X chromosome as well as testosterone deficiency contribute to this pathological pattern. The majority of patients with KS is diagnosed during adulthood, but symptoms can already become obvious during infancy, childhood or adolescence. The paediatric and juvenile patients with KS require specific attention regarding their development and fertility.

CONCLUSION

These guidelines provide recommendations and suggestions to care for patients with KS in various developmental stages ranging from childhood and adolescence to adulthood. This advice is based on recent research data and respective evaluations as well as validations performed by a group of experts.

Hormonal Effects on Hair Follicles

The hair cycle and hair follicle structure are highly affected by various hormones. Androgens—such as testosterone (T); dihydrotestosterone (DHT); and their prohormones, dehydroepiandrosterone sulfate (DHEAS) and androstendione (A)—are the key factors in terminal hair growth. They act on sex-specific areas of the body, converting small, straight, fair vellus hairs into larger darker terminal hairs. They bind to intracellular androgen receptors in the dermal papilla cells of the hair follicle. The majority of hair follicles also require the intracellular enzyme 5-alpha reductase to convert testosterone into DHT. Apart from androgens, the role of other hormones is also currently being researched—e.g., estradiol can significantly alter the hair follicle growth and cycle by binding to estrogen receptors and influencing aromatase activity, which is responsible for converting androgen into estrogen (E2). Progesterone, at the level of the hair follicle, decreases the conversion of testosterone into DHT. The influence of prolactin (PRL) on hair growth has also been intensively investigated, and PRL and PRL receptors were detected in human scalp skin. Our review includes results from many analyses and provides a comprehensive up-to-date understanding of the subject of the effects of hormonal changes on the hair follicle.

Psychosexual effects resulting from delayed, incomplete, or absent puberty

Puberty is a remarkable period of postnatal development culminating in reproductive capacity. Biological changes of puberty are accompanied by social and emotional changes including psychosexual development. Developmental changes of adolescence are influenced by numerous biological, psychological and social influences. Work to date has identified associations between disrupted puberty (i.e. delayed, incomplete or absent) and psychosexual development. This brief review summarizes our current understanding of the psychosexual effects of delayed puberty and congenital hypogonadotropic hypogonadism (Kallmann syndrome). The importance of psychosocial support and transitional care is highlighted and future directions are discussed.

GnRH Deficient Patients With Congenital Hypogonadotropic Hypogonadism: Novel Genetic Findings in ANOS1, RNF216, WDR11, FGFR1, CHD7, and POLR3A Genes in a Case Series and Review of the Literature

Background: Congenital hypogonadotropic hypogonadism (CHH) is a rare genetic disease caused by Gonadotropin-Releasing Hormone (GnRH) deficiency. So far a limited number of variants in several genes have been associated with the pathogenesis of the disease. In this original research and review manuscript the retrospective analysis of known variants in ANOS1 (KAL1), RNF216, WDR11, FGFR1, CHD7, and POLR3A genes is described, along with novel variants identified in patients with CHH by the present study. Methods: Seven GnRH deficient unrelated Cypriot patients underwent whole exome sequencing (WES) by Next Generation Sequencing (NGS). The identified novel variants were initially examined by in silico computational algorithms and structural analysis of their predicted pathogenicity at the protein level was confirmed. Results: In four non-related GnRH males, a novel X-linked pathogenic variant in ANOS1 gene, two novel autosomal dominant (AD) probably pathogenic variants in WDR11 and FGFR1 genes and one rare AD probably pathogenic variant in CHD7 gene were identified. A rare autosomal recessive (AR) variant in the SRA1 gene was identified in homozygosity in a female patient, whilst two other male patients were also, respectively, found to carry novel or previously reported rare pathogenic variants in more than one genes; FGFR1/POLR3A and SRA1/RNF216. Conclusion: This report embraces the description of novel and previously reported rare pathogenic variants in a series of genes known to be implicated in the biological development of CHH. Notably, patients with CHH can harbor pathogenic rare variants in more than one gene which raises the hypothesis of locus-locus interactions providing evidence for digenic inheritance. The identification of such aberrations by NGS can be very informative for the management and future planning of these patients.