MRCEM Notes

Kallman's syndrome

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
  • 'delayed puberty'
  • hypogonadism, cryptorchidism
  • anosmia
  • sex hormone levels are low
  • LH, FSH levels are inappropriately low/normal
  • patients are typically of normal or above average height

Cleft lip/palate and visual/hearing defects are also seen in some patients
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