Searchable abstracts of presentations at key conferences in endocrinology

ea0079012 | Abstracts | BES2021

The impact of anti-androgen therapy on bone in men treated for paraphilia: a retrospective cohort study

Anais De Landtsheer , Lieslinde Bekaert , Leen Antonio , Dirk Vanderschueren

Background: Guidelines suggest treating paraphilias with androgen-deprivation therapy (ADT). However little evidence is available about the long-term impact on bone and how to manage this adverse event.Aim: The aim of this study is to assess the impact of ADT on bone mass and bone mineral density (BMD) in men treated for hypersexuality with cyproterone acetate (CPA) and GnRH agonists (GnRHa), and to evaluate the effect of treatment with bisphosphonates.<...

ea0084ps1-05-44 | Miscellaneous | ETA2022

The effect of testosterone supplementation on the hpt axis in euthyroid hypogonadal adult men: a prospective observational study

David Karel , Antonio Leen , Claessens Frank , Vanderschueren Dirk , Decallonne Brigitte

Background and Objective: It is known that androgens decrease and estrogens increase TBG. In female to male transsexuals under testosterone replacement, decrease of TBG has been shown, but also an increased T3/T4 ratio despite stable free T4 and TSH, suggesting increased conversion to T3 by testosterone. We wanted to study the HPT axis in hypogonadal cis-males before and after testosterone replacement.Method: Prospective observational study in adult male...

ea0070aep204 | Bone and Calcium | ECE2020

High serum FSH is not a risk factor for low bone mineral density in infertile men

Antonio Leen , Priskorn Lærke , Olesen Inge A , Vanderschueren Dirk , Joergensen Niels

Background: Male infertility is associated with a higher long-term morbidity and mortality risk. However, it is not clear which diseases are contributing to this risk. Osteoporosis is a possible factor, as it is a frequent disease and sex steroids regulate both fertility and bone health. Furthermore, there are data indicating that high FSH levels in women are related to low bone mineral density (BMD), independent of estradiol levels. As infertile men often have increased FSH, ...

ea0056p960 | Male Reproduction | ECE2018

Endogenous testosterone supports spermatogenesis even in the absence of gonadotrophins: evidence from a case report

Antonio Leen , Albersen Maarten , Billen Jaak , Maleux Geert , Van Rompuy Anne-Sophie , Vanderschueren Dirk

Background: In patients with testicular dysgenesis syndrome, reduced semen quality and testicular cancer are common. We report a case of a testicular tumour in a patient with a history of cryptorchidism and oligoasthenospermia. He had an unusual hormonal profile, which was not fully explained by the pathological findings.Case: A 31-year-old man was referred to our tertiary care andrology unit for primary infertility with a history of bilateral orchidopex...

ea0071028 | Fertility in men with 5-alpha reductase deficiency | BES2020

Fertility in men with 5-alpha reductase deficiency

Wout Devlies , Elisabet Van Loon , Steven Joniau , Frank Claessens , Leen Antonio , Dirk Vanderschueren

Introduction: 5 Alpha reductase deficiency (5-ARD) is a rare autosomal recessive disorder causing disturbance of sex development. 5 Alpha reductase is an enzyme involved in steroid metabolism, catalyzing testosterone into dihydrotestosterone (DHT), its potent form. 5-ARD therefore results in lower DHT and higher testosterone values. DHT is crucial for the differentiation of the urogenital sinus and genital tubercle into the external genitalia, urethra and prostate, while the v...

ea0099p195 | Late-Breaking | ECE2024

Age-stratified reference ranges for directly measured serum free testosterone in healthy men

Walravens Joeri , Snaterse Gido , Narinx Nick , Antonio Leen , Reyns Tim , Fiers Tom , Kaufman Jean-Marc , Lapauw Bruno

Introduction: Determination of serum (calculated) free testosterone (FT) in clinical practice has been suggested by several clinical guidelines for the diagnosis of male hypogonadism in men with borderline total T concentrations and in situations with altered sex hormone-binding globulin, as it correlates better with androgen exposure than total T. The gold-standard for the determination of FT levels is considered to be directly measured free testosterone (mFT) using equilibri...

ea0081rc12.3 | Rapid Communications 12: Reproductive and Developmental Endocrinology | ECE2022

Binding affinity affecting SHBG SNPs do not majorly affect calculated estimates of free testosterone

Walravens Joeri , Banica Thiberiu , Van Den Eynde Tibbert , Snaterse Gido , Reyns Tim , Narinx Nick , Antonio Leen , Fiers Tom , Kaufman Jean-Marc , Lapauw Bruno

Introduction: According to the free hormone transport hypothesis, only free testosterone (FT) is considered biologically active. Due to low circulating levels and technical challenges of direct FT measurements, calculators have been developed to estimate FT from serum total T, sex hormone-binding globulin (SHBG) and albumin levels. However, genetic polymorphisms altering SHBG’s binding affinity or capacity might result in calculation imprecisions with consequent incorrect...

ea0064002 | Sexual Dimorphism in Bone Size is Mediated by Neuronal ER alpha (ERα) Signaling in Females during Late Puberty | BES2019

Sexual Dimorphism in bone size is mediated by neuronal ER alpha (ERα) signaling in females during late puberty

Nari Kim , Ferran Jardi , Rougin Khalil , Leen Antonio , Dieter Schollaert , Ludo Deboel , van Lenthe GH , Brigitte Decallonne , Geert Carmeliet , Claes Ohlsson , Lagerquist Marie K , Frank Claessens , Dirk Vanderschueren

Introduction: Pubertal sex steroids are indispensable for peak bone mass acquisition as well as skeletal sexual dimorphism. In males, both androgen receptor (AR) and estrogen receptor alpha (ERα) are required for optimal periosteal cortical bone expansion, while estrogens limit bone size in females. In early puberty, estrogens directly stimulate longitudinal growth via ERα in cartilage, but also indirectly via growth hormone (GH) and insulin-like growth factor I (IGF...

ea0071002 | Novel model of sex steroid deficiency in mice to study the physiological effects of delayed and suppressed puberty | BES2020

Novel model of sex steroid deficiency in mice to study the physiological effects of delayed and suppressed puberty

Kim Na Ri , Rougin Khalil , Karel David , Leen Antonio , Dieter Schollaert , Ludo Deboel , HerckErik Van , Nele Wardenier , Martine Cools , Brigitte Decallonne , Frank Claessens , Vanessa Dubois , Dirk Vanderschueren

Background: Sex steroids are critical for skeletal development and maturation during puberty as well as skeletal maintenance during adult life. However, the exact time during puberty when sex steroids have the highest impact as well as the ability of bone to recover from transient sex steroid deficiency is unclear. The latter is highly relevant in the clinical context of delayed puberty, since the impact of a delayed pubertal onset on adult bone health remains elusive. Surgica...

ea0071016 | Early effects of androgen deprivation on bone and mineral homeostasis in adult men: a prospective cohort study | BES2020

Early effects of androgen deprivation on bone and mineral homeostasis in adult men: A prospective cohort study

Rougin Khalil , Leen Antonio , R. Laurent Michael , Karel David , Ri Kim Na , Pieter Evenepoel , Anton Eisenhauer , Alexander Heuser , Etienne Cavalier , Sundeep Khosla , Frank Claessens , Dirk Vanderschueren , Brigitte Decallonne

Objective: Long-term androgen deprivation therapy (ADT) negatively influences bone. The short-term effects on bone and mineral homeostasis are less known. Therefore, we aimed to investigate the early effects of ADT on calcium/phosphate homeostasis and bone turnover.Design: Prospective cohort study.Methods: Eugonadal adult male sex offenders, who were referred for ADT to the endocrine outpatient clinic, received cyproterone acetate....