What is Kallmann's syndrome?

Kallmann's syndrome is a congenital hormonal condition characterised by the failure of an individual to enter puberty. It is a form of hypogonadotrophic hypogonadism. The underlying cause is a failure in the communication pathways within the body that should operate in order to initiate puberty at the correct time. In particular it is a failure of communication between two structures inside the brain called the hypothalamus and the anterior pituitary gland. This failure of communication results in the sex organs or gonads (testes or ovaries) not maturing in the usual manner during puberty.

Causes, incidence, and risk factors?
Hypogonadotropichypogonadism is caused by a lack of the gonadal stimulating pituitary hormones: follicle stimulating hormone (FSH) and luteinizing hormone (LH).
Normally, the hypothalamus in the brain releases gonadotropin-releasing hormone (GnRH), which stimulates the pituitary gland to release other hormones, including FSH and LH. These hormones tell the female ovaries and male testes to secrete hormones that are responsible for normal sexual development in puberty. A disruption in this chain of events causes a deficiency of the sex hormones and prevents normal sexual maturity.
Failure of the hypothalamus is most commonly a result of Kallmann syndrome. Kallmann syndrome is an inherited form of hypogonadotropichypogonadism that can be associated with a loss of smell.

Symptoms
• Absence of secondary sexual characteristics such as pubic, facial, and underarm hair
• Inability to smell (in some cases)
• Lack of development at puberty (may involve incomplete development or a significant delay in development)
• Underdeveloped testicles
• Short stature (in some cases)

Signs and tests
Tests that may be done include:
• Blood tests to measure various hormone levels
• LH response to GnRH
• MRI of the head

Treatment
Treatment depends on the source of the problem but may involve:
• Injections of testosterone
• Slow-release testosterone skin patch
• Estrogen and progesterone pills
• GnRH injections
• Testosterone gels

Expectations (prognosis)
With the right hormone treatment, the person can begin puberty and fertility may be restored.
Complications
• Delayed puberty
• Infertility
• Low self-esteem due to late start of puberty (emotional support may be helpful)