Definition

The pituitary gland, the master gland, is a pea-sized structure that is located at the base of the brain. It’s primary role is to produce hormones.which control the production of other endocrine glands in the body.

Hypopituitarism is an uncommon disorder characterized by an insufficient production of of one or more hormones. The pituitary gland also produces its own hormones. When it isn’t functioning properly, it can cause the amount of hormones that other glands produce to diminish. This is a potentially serious problem that requires care from your doctor.

The pituitary gland is responsible for many body functions, including the following:

• Growth
• Blood pressure
• Sex organ function
• Thyroid gland function
• Breast milk production and other aspects of pregnancy
• Conversion of food into energy
• Water balance in the body

Pituitary Gland

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Causes

There are several factors which may cause this condition:

• Tumors of the pituitary gland, hypothalamus, or brain
• Poor blood supply to the pituitary gland
• Head trauma
• Radiation to pituitary gland, head, or neck
• Stroke
• Infections and inflammatory diseases
• Uncommon immune system or metabolic diseases
• A rare complication after pregnancy, called Sheehan’s syndrome
• Metastatic cancer from lung , colon , prostate , or melanoma

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition. The risk factors for hypopituitarism include the following:

• History of childhood cancer (Treatment can damage the endocrine system, which controls hormones.)
• Infections
• Genetics
• Type 1 diabetes
• Sickle cell anemia
• Reduced blood volume or hypovolemia

Symptoms

Symptoms of hypopituitarism usually begin gradually and may not be recognized for a while. Symptoms depend on which hormone or hormones are low. The following are the hormones produced by the pituitary gland and their associated symptoms due to hormone deficiency:

• Growth hormone deficiency:
  • Poor overall growth
  • Short stature
  • Increased blood pressure
  • Central obesity
  • Muscle weakness
  • Small heart
• Thyroid-stimulating hormone deficiency:
  • Sensitivity to cold
  • Weight gain
  • Constipation
  • Hair that is brittle and coarse
  • Heart rate slowed
  • Dry skin
  • Muscle weakness or fatigue
• Adrenocorticotropic hormone (ACTH) deficiency:
  • Fatigue and weakness
  • Low blood pressure
  • Weight loss
  • Increase in skin pigmentation
  • Amenorrhea
• Follicle-stimulating hormone and luteinizing hormone deficiency:
  • Infertility in men and women
  • Vaginal dryness
  • Loss of some gender-specific sexual characteristics (Women may lose hair from their underarms, body, and pubic area.)
  • Reduced libido
  • Amenorrhea
  • Erectile dysfunction
  • Muscle weakness
  • Small testes
  • Breast enlargement in men

Diagnosis

Your doctor will ask about your symptoms and medical history, and perform a physical exam. If necessary, your doctor will refer you to an endocrinologist, a doctor who specializes in treating hormone disorders.

Tests to determine hypopituitarism include taking a blood sample to do the following:

• Measure the levels of hormones produced by the pituitary gland
• Measure the levels of hormones produced by target endocrine glands, which are influenced by the pituitary gland

Provocative tests of pituitary function may also be done. These may include:

• Growth hormone-releasing hormone (GHRH) test
• Arginine stimulation test
• L-dopa
• Clonidine stimulation test
• Insulin tolerance test
• Adrenocorticotropic hormone (ACTH) stimulation test

Once the diagnosis of hypopituitarism is confirmed, lateral skull x-ray imaging tests (eg, an MRI ) are done on the pituitary gland to identify problems such as abnormal tissue and growth or shrinkage of the pituitary gland.

Treatment

Talk with your doctor about the best treatment plan for you. Hypopituitarism is permanent and will likely need to be treated for life. Treatment options include the following:

Prevention

In general, this condition is not preventable. However, being aware of the risks and symptoms will make early diagnosis and treatment possible.