Hypopituitarism

What is hypopituitarism?

Hypopituitarism is a rare condition where your pituitary gland doesn’t make enough of the hormones you need. Hormones are like chemical messages that tell your body what to do. Pituitary hormones control things like metabolism, growth and development, and reproduction.

Your pituitary gland doesn’t act alone. It works together with your hypothalamus. This brain structure tells your pituitary gland to release certain hormones. It also regulates functions like blood pressure, heart rate, body temperature and digestion. If you have a disease or injury that affects your pituitary gland or hypothalamus, you may develop hypopituitarism.

The condition can happen suddenly after an injury or develop slowly over months or years. People with it often need to take medication for the rest of their lives to manage symptoms. Your healthcare provider will watch you closely to make sure you get the right treatment.

What are the different types of hypopituitarism?

There are three different kinds of hypopituitarism based on the number of hormones that are lacking (deficient):

• Isolated pituitary deficiency: Affects one pituitary hormone.
• Multiple pituitary hormone deficiency: Affects two or more pituitary hormones.
• Panhypopituitarism: Affects all pituitary hormones.

There are three kinds of hypopituitarism based on its cause and how it affects your pituitary gland or hormones:

• Primary hypopituitarism: Damage to or disorders of your pituitary gland.
• Secondary hypopituitarism: Damage to or disorders of your hypothalamus.
• Idiopathic hypopituitarism: Cause remains undetermined.

What are the symptoms of hypopituitarism?

The symptoms of hypopituitarism depend on which pituitary hormone(s) is deficient (lacking). The following factors also affect what kind of symptoms you’ll experience:

• Your sex assignment at birth.
• Your age when hypopituitarism begins.
• The cause of hypopituitarism.
• How fast the hormones decrease.

Symptoms of a lack of growth hormone (GH)

Symptoms of growth hormone deficiency in newborns include:

• Hypoglycemia (low blood sugar).
• An abnormally small penis (micropenis).

Symptoms of growth hormone deficiency in children include:

• Slow growth or no growth.
• Short height.
• Missing or delayed sexual development during puberty.

Symptoms of growth hormone deficiency in adults include:

• Fatigue.
• Reduced sense of well-being.
• Decreased sexual function and sexual interest.
• Higher amount of body fat, particularly around the waist.
• Sensitivity to heat and cold.
• Decreased muscle mass.
• Decreased strength and stamina when exercising.

Symptoms of a lack of thyroid-stimulating hormone (TSH)

Symptoms of thyroid-stimulating hormone deficiency in newborns include:

• Decreased muscle tone.
• Low body temperature (hypothermia).
• A bulging belly.
• A hoarse cry.

Symptoms of thyroid-stimulating hormone deficiency in children and adults are similar to symptoms of hypothyroidism, an underactive thyroid. This is because TSH stimulates your thyroid to produce its own hormones.

Symptoms of hypothyroidism include:

• Fatigue.
• Dry skin and thinning hair.
• Constipation.
• Weight gain.
• Muscle weakness.
• Sensitivity to cold temperatures.
• Depression.
• For people assigned female at birth (AFAB), experiencing heavier-than-normal menstrual periods or irregular periods.

Symptoms of a lack of follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH)

FSH and LH are hormones called gonadotropins. They affect your reproductive system.

Symptoms of FSH deficiency and/or LH deficiency in newborns assigned male at birth (AMAB) include:

• An abnormally small penis (micropenis).
• Undescended testicles.

Symptoms of FSH deficiency and/or LH deficiency in children include:

• Absent breast development in children AFAB.
• Absent testicular enlargement in children AMAB.
• Lack of growth spurt during puberty.

Symptoms of FSH deficiency and/or LH deficiency in adults AMAB include:

• Loss of interest in sex (low sex drive).
• Fatigue.
• Infertility.
• Erectile dysfunction.
• Decreased facial or body hair.

Symptoms of FSH deficiency and/or LH deficiency in adults AFAB can include:

• Loss of interest in sex (low libido).
• Fatigue.
• Infertility.
• Hot flashes.
• Irregular periods or no menstrual periods (amenorrhea).
• Decreased pubic hair.
• Lack of breast milk production after giving birth.

Symptoms of a lack of adrenocorticotropic hormone (ACTH or corticotropin)

Symptoms of ACTH deficiency in newborns include:

• Hypoglycemia (low blood sugar).
• The rate of weight gain is significantly lower than average (failure to thrive).
• Seizures.
• Yellowing skin (jaundice).

Symptoms of ACTH deficiency in children and adults include:

• Fatigue.
• Unexplained weight loss.
• Low blood pressure (hypotension).
• Nausea and vomiting.
• Hypoglycemia (low blood sugar).
• Confusion.

Symptoms of a lack of prolactin

The main symptom of prolactin deficiency is a lack of breast milk production after giving birth.

Symptoms of a lack of oxytocin

Symptoms of oxytocin deficiency include:

• Breast milk flow issues after childbirth.
• Difficulty bonding with your baby after birth.
• Lack of empathy.
• Difficulty interacting with others.

Symptoms of a lack of antidiuretic hormone (ADH or vasopressin or arginine vasopressin)

Symptoms of ADH deficiency in newborns include:

• Vomiting.
• Unexplained episodes of fever.
• Excessive crying.
• Weight loss.
• Constipation.
• Very wet diapers.

Symptoms of ADH deficiency in children include:

• Difficulty with toilet training.
• Bedwetting.
• Getting tired easily.

Symptoms of ADH deficiency in adults can include:

• Frequent urination.
• Extreme thirst.
• Having electrolyte imbalances.

What causes hypopituitarism?

Many conditions and situations can cause hypopituitarism. In some cases, healthcare providers can’t determine the cause. In general, these three main factors can cause the condition:

• Something is putting pressure on (compressing) your pituitary gland or hypothalamus.
• There’s damage to your pituitary gland or hypothalamus.
• You have a rare condition or a condition that causes hypopituitarism.

Conditions that affect your pituitary gland or hypothalamus

Conditions that can cause pressure on these areas of your brain, possibly leading to hypopituitarism, include:

• Pituitary adenomas: A benign tumor on your pituitary gland that can change the way it releases hormones.
• Brain tumors: A brain tumor near your hypothalamus and/or pituitary gland can affect hormone production.
• Lymphocytic hypophysitis (LH): This is a rare condition where lymphocytes invade your pituitary gland.
• Pituitary or hypothalamus sarcoidosis: Sarcoidosis is a disease that causes inflammation.

Injuries that cause damage to your pituitary gland or hypothalamus

Examples of situations that can cause pituitary or hypothalamus damage include:

• Surgery: Complications from brain surgery (especially surgery to remove a pituitary adenoma).
• Radiation therapy: Prior cancer radiation therapy or radiation used to treat a pituitary adenoma.
• Traumatic brain injury: Situations like a vehicle accident, a fall or contact sports.
• Pituitary apoplexy: Sudden destruction of pituitary gland tissue.

Rare conditions

Examples of rare conditions that can cause the condition include:

• Hereditary hemochromatosis: This genetic condition causes too much iron in your bloodstream. It can damage your pituitary gland.
• Bacterial meningitis: Although it’s rare, hypopituitarism can be a complication of bacterial meningitis.
• Genetic mutations: Some rare genetic conditions can cause deficiencies in pituitary hormones.

What are the risk factors?

The following conditions or situations may be risk factors for hypopituitarism:

• A history of cancer and radiation therapy.
• Head or brain trauma: Approximately 27% to 32% of people who experience a traumatic brain injury (TBI) develop hypopituitarism.
• Sickle cell anemia: Sickle cell anemia can cause a deficiency of pituitary hormones.
• Type 1 diabetes: Nerve and vascular damage from unmanaged Type 1 diabetes can contribute to the condition.
• Pregnancy and giving birth: Severe blood loss (hemorrhaging) after childbirth can result in pituitary damage. This is known as Sheehan syndrome.

Complications

Hormonal deficiencies that accompany hypopituitarism can lead to the development of other conditions. The exact effects vary depending on which hormone is lacking. Some examples are:

• GH deficiency can lead to obesity, high cholesterol and metabolic syndrome.
• Estrogen deficiency (from FSH deficiency) can lead to osteoporosis in people AFAB.
• ACTH deficiency can lead to an adrenal crisis.

What tests will be done to diagnose the condition?

Your healthcare provider may order any of the following tests to diagnose hypopituitarism:

• Hormone level blood tests: Your provider may order different blood tests that measure the levels of certain hormones in your blood depending on your symptoms.
• Hormone stimulation tests: For this test, your provider uses medicine to stimulate your pituitary gland to release the hormone that they’re testing. They then take samples of your blood and send them to a lab for testing.
• Insulin tolerance test: An insulin tolerance test can diagnose growth hormone (GH) and adrenocorticotropic hormone (ACTH or corticotropin) deficiencies.
• Osmolality tests for blood and urine: This test checks for antidiuretic hormone (ADH) deficiency. It requires blood and urine samples.
• MRI (magnetic resonance imaging) scans: MRI scans use radio waves and strong magnets to create detailed images of inside your body. Brain MRIs are considered the best way to find pituitary tumors that could be causing the condition.
• Brain CT (computed tomography) scan: Your provider may use this test to see if you have a brain tumor or pituitary adenoma that’s causing hypopituitarism.

How is hypopituitarism treated?

There’s no cure, but hypopituitarism is treatable. Treatment depends on which pituitary hormone(s) are deficient and what caused your condition. Your healthcare team will work with you to customize the right treatment plan. Common treatment options for hypopituitarism include:

• Hormone replacement therapy: This aims to restore the deficient pituitary hormone(s) to normal levels. You typically remain on medication for the rest of your life.
• Surgery: People who have pituitary adenomas may need surgery to remove them.
• Radiation therapy: Radiation therapy can help shrink pituitary adenomas.

Your healthcare provider may recommend a medical ID card (or bracelet) that you always keep with you in case of an emergency.

What is the prognosis (outlook) for hypopituitarism?

The outlook varies and depends on the following:

• How old you were when your symptoms began.
• What caused your condition.
• How much your affected hormone(s) are lacking.
• How your body responds to treatment.

While many people with hypopituitarism lead healthy lives, long-term pituitary damage can lower your life expectancy compared to people without the condition of the same age.

What is the life expectancy of someone with this condition?

Your life expectancy depends on the hormone deficiency type, its severity and your overall health. People who follow their treatment plans typically don’t have a lower life expectancy.

Can I die from hypopituitarism?

Although it’s not as common, a sudden and severe onset of hypopituitarism can result in a medical emergency and death if it’s not treated. Be sure to call your healthcare provider or go to the nearest emergency room if you’re experiencing symptoms.

When should I see my healthcare provider?

In most cases, hypopituitarism requires close, lifelong monitoring of the hormones affected. Be sure to see your healthcare provider regularly to make sure your treatment plan is working. If you’re experiencing new or concerning symptoms, contact your healthcare provider as soon as possible.

What questions should I ask my healthcare provider?

If you’ve been diagnosed with hypopituitarism, you may want to ask your healthcare provider the following questions:

• What kind of hypopituitarism do I have?
• Which of my hormones are deficient?
• What’s the cause?
• What are my treatment options?
• Are there side effects of my treatment?
• How often do I have to take my medicine?
• Will it affect my fertility?
• Will it affect my pregnancy?
• Can I pass this on to my children?