Androgens are important in every phase of male life. Testosterone is the most important human androgen. During the embryonal stage, testosterone determines the differentiation of the sexual organs, during puberty development toward the adult male phenotype is testosterone-dependent, and in the adult, testosterone maintains the male phenotype.
Diminished gonadal function is called hypogonadism. As a rule it manifests itself in decreased testosterone production. As a sex hormone with a multitude of influences on physiological processes, its deficiency leads to several functional impairments, which is often the reason for a patient to seek medical help, e.g. fatigue, weakness, loss of libido, erectile dysfunction.
Men with erectile dysfunction and low serum testosterone may benefit from testosterone treatment alone. The combination of phosphodiesterase 5-inhibitors and testosterone may be indicated in those men who did not respond sufficiently to testosterone alone.1 The prevalence for male hypogonadism amongst men with erectile dysfunction is estimated to be around 20%.2,3
Hypogonadism is highly prevalent amongst men with diabetes mellitus type 2 which is a frequent disorder of aging men. Recent guidelines suggest that diabetes in hypogonadal men should be evaluated and treated before or simultaneously with testosterone treatment.1
The usual way to find the correct diagnosis, which includes the consideration of clinico-chemical findings (in this case, determination of serum hormone levels) may prove difficult, because symptoms may not be very specific and laboratory findings may not always provide a clear-cut picture, in particular when the decreased testosterone levels are close to the normal range. Specific tests to evaluate the individual androgen sensitivity are not yet available, so it is often a diagnosis by the physician’s experience after careful exclusion of other diseases that may have caused the symptomatology. The observation of clear clinical benefits of the testosterone therapy is sometimes the only method to verify the indication ex iuvantibus.
References:
1. Nieschlag E, Swerdloff R, Behre HM, Gooren L, Kaufman JM, Legros JJ, Lunenfeld B,Morley J, Schulman C, Wang C, Weidner W, Wu F: Investigation, Treatment and Monitoring of Late-Onset Hypogonadism in Males–ISA, ISSAM, and EAU Recommendations. Europ Urol 2005; 48: 1–4
2. Corona G, Mannucci E, Mansani R, Petrone L, Bartolini M, Giommi R, Forti G, Maggi M: Organic, relational and psychological factors in erectile dysfunction in men with diabetes mellitus. Europ Urol 2004; 46: 222–228.
3.Bodie J, Lewis, J, Schow D, Monga M: Laboratory evaluations of erectile dysfunction: an evidence based approach. J Urol 2003; 169: 2262–2264.