Usually, laboratory diagnostics can be omitted. However, laboratory diagnostics are obligatory (indispensable) in case of bilateral nonpalpable testis!
1st order laboratory parameters – obligatory laboratory tests – in bilaterally nonpalpable testes.
- Gonadotropins (LH, FSH – in suspected anorchia (absent testis).
- Inhibin-B (inhibin B is produced in the Sertoli cells of the male. It directly inhibits and regulates FSH secretion in the pituitary gland. The combination of determination of FSH and Inhibin B serum levels is currently considered the best indicator of impaired sertoli cell function or spermatogenesis). – For the detection of testosterone-producing tissue [in suspected anorchia/absent testis].
- HCG test (HCG stimulation test; Leydig cell function test) Test to detect functional Leydig cells (= detection of testosterone-producing tissue). In this test, the endocrine capacity of the testes (testicles) is checked by stimulation with human chorionic gonadotropin (HCG). HCG has predominantly LH activity and stimulates testosterone production of Leydig cells – to differentiate between anorchia (absent testis) and cryptorchidism (testis is not palpable and has an intra-abdominal location) [no longer gold standard].
- Chromosomal analysis – in cases of bilateral nonpalpable testis, intersexual genitals, and/or hypospadias (lower urethral cleft); to exclude a female karyotype with concomitant adrenogenital syndrome (AGS) [autosomal recessive inherited metabolic disorder characterized by disorders of hormone synthesis in the adrenal cortex; these disorders lead to a deficiency of aldosterone and cortisol; leads to virilization (masculinization) in girls]
