Endocrine Abstracts

Spermatogenic disruption is normally recognized by low sperm count and FSH levels. However, Leydig cell impairment is also frequent in subjects with primary testicular damage, as evidenced for example by reduced INSL3 and 25(OH)-vitamin D levels. The latter is caused by reduced expression of CYP2R1, a major enzyme involved in 25-hydroxylation of cholecalciferol. Furthermore, testosterone (T) production by the Leydig cells might be also impaired in men with primary spermatogenic damage. To clarify these we evaluated the presence and type of hypogonadism, 25(OH)-vitamin D status and bone mass in a very large cohort of infertile males. Among subjects referred to our tertiary Universitary Centre for semen analysis during the period January 2011 to June 2014 (11 516 semen analysis) we report here the data of men who completed the andrological program, including semen culture (n: 10 394), history and physical examination (n: 7527), hormone analysis (FSH, LH, T, 25(OH)-vitamin D; n: 5884), and ultrasound of the testes (n: 5177). Men with total sperm count <10 million/ejaculate (n: 2583) underwent also genetic analysis (karyotype, Yq microdeletions, CFTR mutations; n: 2273) and DXA (n: 855). Azoospermia was present in 9.3% of cases, oligozoospermia (with or without reduced motility and/or normal sperm morphology) in 40.6%, asthenozoospermia in 12.2%, and normozoospermia in 34.5%. Main causes or risk factors were varicocele (28%), genetics (15%), obstruction/sub-obstruction of seminal tract (12%), cryptorchidism (6%), infections/iatrogenic causes/ejaculation disorders/prior surgery (14%) and idiopathic forms (25%). Primary hypogonadism (T<10.4 nmol/l, LH>8 IU/l) was found in 25.7% of cases, secondary hypogonadism (T<10.4 nmol/l, LH<1.5 IU/l) in 1.3%, subclinical hypogonadism (T>10.4 nmol/l, LH >8 IU/l) in 34.2%. Men with all forms of hypogonadism have frequently insufficient (48.5%) or deficient (25.4%) 25(OH)-vitamin D levels and higher risk of low bone mass, osteoporosis (16.8%) and osteopenia (31.5%). This study showed that hypogonadism and low vitamin D levels are very frequent in infertile males. Both conditions are implicated in the frequent low bone mass seen in these patients. Metabolic and other clinical conditions associated with low T and low vitamin D levels need therefore to be accurately evaluated in these subjects, and treatment should consider also these aspects.