Hypopituitarism

What is hypopituitarism?

Hypopituitarism happens when your pituitary gland is not active enough. As a result the gland does not make enough pituitary hormones.

The pituitary is a small gland at the base of your brain. It is one of several glands that make hormones. Hormones are chemicals that send information and instructions from one set of cells to another. The pituitary gland makes many types of hormones. These hormones affect many things, including bone and tissue growth, your thyroid gland, and sexual development and reproduction.

What causes hypopituitarism?

Causes can directly affect the
pituitary gland. Or they can indirectly affect the gland through changes in the
hypothalamus. This is a part of the brain that is just above the pituitary gland. The
hypothalamus makes hormones that help the pituitary gland work normally.

Direct causes include:

  • Pituitary tumors
  • Poor blood supply to the pituitary gland
  • Infections or inflammatory diseases of
    the brain
  • Radiation treatment
  • Surgery to remove pituitary tissue
  • Autoimmune diseases
  • Brain injury
  • Genetic diseases and syndromes
  • Rare diseases such as sarcoidosis and
    amyloidosis

Indirect causes include:

  • Hypothalamus tumors
  • Inflammatory disease or a disease that
    spreads to the pituitary, such as cancer 
  • Head injuries
  • Surgical damage to the hypothalamus or
    blood vessels or nerves leading to it
  • Certain medicines such as opioids that decrease hormone
    secretion from the hypothalamus

What are the symptoms of hypopituitarism?

Symptoms are different for each person. They may happen over time or right away. They depend on which hormones the pituitary gland is not making enough of. These hormone deficiencies, and the symptoms they cause, include:

  • Not enough gonadotropins (luteinizing
    hormone and follicle-stimulating hormone).
    This affects women who have not
    gone through menopause. They may not have a menstrual period. They may have problems
    with fertility, vaginal dryness, and loss of some female traits. Men may have
    problems with fertility, sexual function, and loss of some male traits. Children will
    not go through puberty.
  • Not enough growth hormone. Adults
    with this problem may lose bone and muscle mass. In children it can lead to stunted
    growth and dwarfism.
  • Not enough thyroid-stimulating hormone.
    This often leads to an underactive thyroid. It may cause lack of energy
    (fatigue), confusion, inability to handle the cold, weight gain, constipation, and
    dry skin.
  • Not enough ACTH (adrenocorticotropin
    hormone).
    This is rare. It leads to an underactive adrenal gland. You may
    have low blood pressure, low blood sugar, feel tired, and be easily stressed.
  • Not enough prolactin. This is rare.
    Women who lack this hormone may not be able to make breastmilk after childbirth.
  • Not enough antidiuretic hormone (also called
    vasopressin).
    This leads to increased urine output and thirst.

These symptoms may look like other health problems. Always see your healthcare provider for a diagnosis.

How is hypopituitarism diagnosed?

Your healthcare provider will ask
about your health history. You will also need an exam. Other tests you may need
include:

  • CT scan. This test uses X-rays and
    computer technology to make detailed images of your body.
  • MRI. This test uses large magnets,
    radio waves, and a computer to make images of organs and structures within your
    body.
  • Blood and urine tests. These tests measure hormone levels in your body.