The table below summarises the findings in patients who have disorders of sex hormones:
| Disorder | LH | Testosterone |
|---|---|---|
| Primary hypogonadism (Klinefelter's syndrome) | High | Low |
| Hypogonadotrophic hypogonadism (Kallman's syndrome) | Low | Low |
| Androgen insensitivity syndrome | High | Normal/high |
| Testosterone-secreting tumour | Low | High |
Klinefelter's syndrome is associated with karyotype 47, XXY
Features
Diagnosis is by chromosomal analysis
Kallman's syndrome is a recognised cause of delayed puberty secondary to hypogonadotrophic hypogonadism. It is usually inherited as an X-linked recessive trait. Kallman's syndrome is thought to be caused by failure of GnRH-secreting neurons to migrate to the hypothalamus.
The clue given in many questions is lack of smell (anosmia) in a boy with delayed puberty
Features