When the male gonad fails

Male Hypogonadism: Basic, Clinical, and Therapeutic Principles is an excellent guide for clinicians and researchers, as well as students of andrology interested in understanding the causes and possible therapies for male hypogonadism. The book contains 19 chapters, of which the first three are dedicated to the basics and background of testicular function and the neuroendocrine control of testicular function, Leydig cell function and spermatogenesis. The next seven chapters describe the various ways in which male hypogonadism can occur as a result of genetic disorders affecting the hypothalamic–pituitary–testicular axis. The subsequent three chapters describe the impact of chronic illness on testicular function and the three that follow describe the effects of age, environment, exercise and obesity on testicular functions. The final two chapters discuss androgen replacement and gonadotropin stimulation of spermatogenesis as possible therapies for hypogonadism.Hypogonadism resulting from genetic disorders manifests in a very small percentage of the population and can have a myriad of causes, including mutations in the gonadotropin or cognate receptor genes, crytorchidism, congenital adrenal hyperplasia and Klinefelter's syndrome. A chapter that stands out in this section is authored by Crowley and Pitteloud and describes congenital hypogonadotrophic hypogonadism. The authors provide a comprehensive review of the causes and evaluation of hypogonadism. However, some of the descriptions of the disorders and/or syndromes require cross-reference to other chapters in the book for further analysis. For example, mutations in gonadotropin subunits and their receptors that cause hypogonadism are reviewed in depth by Huhtaniemi, who argues that, although some patients with inactivating or activating mutations in gonadotropin genes and their receptors have been diagnosed, an emphasis larger than that currently given should be placed on the polymorphisms in these genes in the general population and their effects on delayed puberty and other phenotypic effects.Mass lesions in the pituitary and suprasellar regions (described by Colao et al.) have effects on GnRH secretion that can cause hypogonadism. This chapter is well organized and aspects related to the pathophysiology, diagnosis and treatment options for each type of tumor and/or disorder are described. Other excellent chapters include reviews of hypogonadism in men with AIDS, chronic renal failure and cancer. Androgen deficiency is only a secondary aspect of AIDS; however, the readers are led through interesting data that suggest that androgen deficiency can be caused by energy deficits subsequent to muscle loss, and/or poor nutrition, which in turn are associated with decreased GnRH secretion. This can lead to adverse outcomes for HIV-infected men. It is also suggested that androgen replacement therapy could markedly improve the quality of life of AIDS patients.Hypoandrogenemia caused by age is described as a natural and the common consequence of the regulatory failure of the HPG axis. However, exposure to toxins during prenatal or adult life and lifestyle and/or environmental factors are considered to be preventable. The use of anabolic steroids by athletes and overtraining are presented in an interesting chapter. The adverse side effects caused by steroid use appear to occur because of readjustment of the HPG axis and shifting of the baseline levels of circulating testosterone. The final two chapters provide treatment options for male hypogonadism, such as testosterone replacement and stimulation of spermatogenesis by gonadotropins. Both chapters give extensive insight into the methods of evaluation of the patients and the benefits and risks of such therapies.Readers of Male Hypogonadism are assured of a comprehensive coverage of the causes of and effective therapies for male hypogonadism. The information is covered both from a clinical standpoint and also with an emphasis on the cutting edge research in this field. Male Hypogonadism would be a valuable addition to the bookshelf of any clinician or researcher interested in this field.