Searchable abstracts of presentations at key conferences in endocrinology

ea0097016 | Section | BES2023

SHBG assay performance and the effect of SHBG assay choice on calculated free testosterone

Joeri Walravens , Tim Reyns , Eynde Tibbert Van Den , Joanne Adaway , Brian Keevil , Tom Fiers , Bruno Lapauw

Objective: To investigate performance of sex hormone binding globulin (SHBG) assays of different manufacturers and the effects of assay choice on calculated free testosterone (cFT).Methods: Anonymized serum samples of 113 men and 106 women were randomly selected from excess material from the routine clinical lab at the University Hospital of South Manchester. SHBG levels were measured using three different immunoassays (...

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...