May present with features of testosterone deficiency and/or infertility.
When caused by pituitary macro-adenoma, patients may have additional symptoms due to mass effects, such as headaches or peripheral visual disturbance. There may also be signs and symptoms of other pituitary hormone deficiencies.
Early morning serum total testosterone level below 10.4 nanomol/L (<300 nanograms/dL) on at least two separate occasions in a symptomatic man generally confers the diagnosis of hypogonadism.
Testosterone should be measured in all men with erectile dysfunction.
Measurement of the gonadotrophins (LH and FSH) distinguishes between a primary and a secondary cause.
The aim of testosterone therapy is to achieve serum testosterone levels within the normal physiological range with dose adjustment to have the maximum effect on alleviation of symptoms.
Hypogonadism in males is a clinical syndrome that comprises symptoms and/or signs, along with biochemical evidence of testosterone deficiency.
The male gonads (testes) have 2 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.
History and exam
Key diagnostic factors
- decreased libido
- loss of spontaneous morning erections
- erectile dysfunction
- small testes
- bifid scrotum
- eunuchoid proportions
- bitemporal hemianopia
- low trauma fractures
- loss of height
Other diagnostic factors
- decreased energy and fatigue
- delayed puberty
- lack of scrotal hyper-pigmentation and rugae
- decreased muscle mass and strength
- loss of axillary and pubic hair
- lack of facial hair
- poor concentration and memory
- depressed mood
- sleep disturbance
- hot flushes and sweats
- increasing BMI
- tall stature
- fine wrinkling of facial skin
- genetic anomaly
- type 2 diabetes mellitus
- use of alkylating agents, opioids, or glucocorticoids
- use of exogenous sex hormones and GnRH analogues
- pituitary tumour or apoplexy
- critical illness
- testicular damage
- auto-immune testicular damage
1st investigations to order
- serum total testosterone
Investigations to consider
- serum sex hormone binding globulin (SHBG)
- serum free testosterone
- serum bioavailable testosterone
- serum LH/FSH
- serum prolactin
- serum Fe, TIBC, and ferritin
- MRI pituitary
- semen analysis
- genetic testing
- serum TSH
- dual-energy X-ray absorptiometry (DEXA or DXA)
Charles Welliver, MD
Assistant Professor of Surgery
Division of Urology
Albany Medical College
CW has worked as a consultant for Coloplast, and as an investigator for Auxilium Pharmaceuticals, Mereo BioPharma, PROCEPT BioRobotics, and Repros; and he is a paid reviewer at Oakstone Publishing and BMJ Best Practice. CW also has a family member who is an employee at Bristol-Myers Squibb.
Dr Charles Welliver would like to gratefully acknowledge Matthew Aoun for his help with updating this topic. He would also like to acknowledge Dr T. Hugh Jones, Dr Milena Braga-Basaria, and Dr Shehzad Basaria, previous contributors to this monograph. THJ and SB are authors of references cited in this topic. MB declared that she had no competing interests.
Randal J. Urban, MD
Department of Internal Medicine
University of Texas Medical Branch
RJU declares that he has no competing interests.
Niki Karavitaki, MBBS, MSc, PhD
Oxford Centre for Diabetes, Endocrinology and Metabolism
NK declares that she has no competing interests.
- Pituitary macro-adenoma
- Testosterone therapy in adult men with androgen deficiency syndromes
- Guidelines on male infertility
Fertility problems: what goes wrong?More Patient leaflets
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