Hypogonadism in men

Hypogonadism in men may present with reproductive/sexual clinical features (e.g., incomplete pubertal development, infertility, gynaecomastia), as well as non-reproductive features (e.g., fatigue, osteoporosis, loss of motivation or concentration, irritability, low or labile mood, body image concerns).

Patients may have additional symptoms due to mass effects when caused by large parasellar lesions (e.g., headache, peripheral visual disturbance), or may have signs or symptoms of other hormone deficiencies.

Early morning fasting serum total testosterone level below 10.4 nanomol/L (<300 nanograms/dL) on at least two separate occasions in a man with one or more clinical features confers the diagnosis of hypogonadism in most cases.

Measurement of the gonadotrophins (luteinising hormone [LH], follicle stimulating hormone [FSH]) distinguishes between a primary cause (dysfunction of the testes) and a secondary (also known as central or hypogonadotrophic) cause (pituitary or hypothalamic dysfunction).

Management of men with low testosterone due to non-gonadal illness (e.g., obesity) is to optimise treatment of the underlying condition.

Testosterone therapy is used to achieve normal physiological serum testosterone levels, with dose adjustment to maximum effect on relevant clinical features (without causing erythrocytosis).

Hypogonadism in males is a clinical syndrome that comprises symptoms and/or signs, along with biochemical evidence of testosterone deficiency.[1]Mulhall JP, Trost LW, Brannigan RE, et al. Evaluation and management of testosterone deficiency: AUA guideline. J Urol. 2018 Aug;200(2):423-32. https://www.auajournals.org/doi/10.1016/j.juro.2018.03.115 http://www.ncbi.nlm.nih.gov/pubmed/29601923?tool=bestpractice.com [2]Jayasena CN, Anderson RA, Llahana S, et al. Society for Endocrinology guidelines for testosterone replacement therapy in male hypogonadism. Clin Endocrinol (Oxf). 2022 Feb;96(2):200-19. https://onlinelibrary.wiley.com/doi/epdf/10.1111/cen.14633 http://www.ncbi.nlm.nih.gov/pubmed/34811785?tool=bestpractice.com

The male gonads (testes) have two primary functions: testosterone production (by the Leydig cells) and spermatogenesis (by the spermatogenic and Sertoli cells in the seminiferous tubules). Hypogonadism in men occurs where there is dysfunction in the normal physiological mechanism of the hypothalamic-pituitary-gonadal axis that results in a decreased ability to carry out either of these functions.