Hypogonadotropic hypogonadism

Abstract

Hypogonadotropic hypogonadism (HH) is a congenital (CHH) or acquired (AHH) clinical condition characterized by low serum testosterone in association with absent or decreased levels of circulating luteinizing hormone (LH) and folliclestimulating hormone (FSH) concentrations [ 1 ]. The FSH and LH secretion and synthesis patterns are impaired in patients with HH. The prevalence of acquired and congenital HH has been estimated in range from 1:4,000 to 1:86,000 in males, and it is reported to be between two and fi ve times less frequent in females [ 2 ]. Approximately 60 % cases of CHH are related to Kallmann syndrome. The rest of the causes includes gonadotropin-releasing hormone (GnRH) insensitivity syndrome (20 % of cases) and inactivating mutations in a variety of other genes which regulate GnRH secretion (less than 5-10 %) [ 3 ]. Acquired hypogonadotropic hypogonadism in adult males is mainly associated with hyperprolactinemic states, obesity, and diabetes type II. The cause of HH is unknown in about 30 % of all cases and these men are diagnosed as having idiopathic isolated HH [ 4 ].