Pituitary Conditions
Pituitary Gland conditions
Hypopituitarism
Hypopituitarism is a condition in which there's a lack of one, multiple or all of the hormones which the pituitary gland makes.
Most cases of hypopituitarism involve one hormone deficiency. A deficiency in two or more of the pituitary hormones is called panhypopituitarism. This typically happens after pituitary surgery or brain radiation.
Hypopituitarism is most often caused by some type of damage to your pituitary gland or hypothalamus or Tumour.
Hyperpituitarism
Hyperpituitarism happens when your pituitary gland makes too much of one or more hormones. It's often caused by a functioning/secreting pituitary tumor.
If hormones are being over-produced, then this can cause problems depending on which hormones are affected.
Acromegaly
Acromegaly is caused by a benign tumor on the pituitary gland called an adenoma which causes the pituitary to produce too much Growth Hormone (GH). This stimulates the pituitary gland to produce GH. Secretion of GH by the pituitary into the bloodstream which stimulates the liver to produce another hormone called Insulin-like Growth Factor 1 (IGF-1). IGF-1 causes tissue growth in the body.
Adrenal Deficiency
In people who have adrenal insufficiency, the adrenal glands stop working properly and aren't able to produce hormones which are crucial to keeping the body functioning correctly. Adrenal insufficiency has multiple causes, giving three different types of adrenal insufficiency: primary (adrenal), secondary (pituitary), and tertiary (hypothalamus). The type of adrenal insufficiency (primary, secondary or tertiary) depends on whether the problem lies in the adrenal gland or is due to impairment of the hypothalamus and pituitary gland.
Arginine Vasopressin Deficiency (AVP-D)
AVP - Deficiency, formerly known as Diabetes insipidus (DI), is caused by a problem with either the production, or action, of the hormone vasopressin (AVP). If you have AVP-D your kidneys are unable to retain water.
This leads to the production of large volumes of urine and, in turn, greatly increased thirst. AVP Deficiency can occur at any age, but is mostly found in adults. It is a rare disorder, affecting only about 1 in 25,000 people.
Cushing's Disease
Cushing's syndrome develops if your body makes too much of a hormone called cortisol.
Cortisol is made by the adrenal glands (two small glands which lie just above each kidney) and it is vital for life. It has several functions including
The most common cause of spontaneous Cushing's is a small benign tumor of the pituitary gland. This tumor causes the pituitary gland to produce too much of a hormone called ACTH, (adrenocorticotrophic hormone), which goes through the blood stream to the adrenal glands and causes them to release too much cortisol.
Prolactinoma
What is a Prolactinoma?
A prolactinoma is a non-cancerous (benign) tumor of the pituitary gland that produces excessive amounts of the hormone prolactin. It is the most common type of hormone-producing pituitary tumor.
The pituitary gland is a small gland located at the base of the brain that controls many important hormones in the body. A prolactinoma develops when cells in the pituitary gland grow and produce too much prolactin, a hormone primarily involved in breast development and milk production.
You may hear healthcare professionals use terms such as tumor, adenoma, or growth when describing a prolactinoma. These terms simply refer to an abnormal enlargement within the pituitary gland. Prolactinomas are benign and are not brain tumors or cancer. They typically grow very slowly, and many remain the same size for years.
Types of Prolactinomas
Prolactinomas are classified according to their size:
- Microprolactinomas are smaller than 10 mm in diameter and are the most common type.
- Macroprolactinomas are larger than 10 mm in diameter and are less common.
Who Can Be Affected?
Prolactinomas can occur in both women and men, although they are diagnosed more frequently in women. The symptoms experienced can vary depending on a person's sex, age, hormone levels, and the size of the tumor.
What Causes a Prolactinoma?
The exact cause of prolactinomas is not fully understood. In most cases, they occur spontaneously and are not linked to lifestyle factors or anything a person has done. Rarely, prolactinomas may occur as part of an inherited condition affecting the endocrine system.
With appropriate diagnosis, monitoring, and treatment, most people with a prolactinoma can successfully manage their condition and lead healthy, active lives.
Growth Hormone Deficiency
GH deficiency in Children and Adults can may have different root causes but is usually caused by damage to the pituitary gland or the part of the brain which controls this gland (the hypothalamus). The damage may be due to a tumor, the effects of treatment for the tumor or problems with the blood supply to the pituitary gland.
Typical symptoms
There are a range of symptoms that affect people with growth hormone deficiency, you may not experience all of these:
increase in adipose (fatty) tissue (especially around the waist)
decrease in lean body mass (muscle)
decrease in strength and stamina, reduction in exercise capacity
decrease in bone density, increase in rate of fracture in middle age and beyond
changes in blood cholesterol concentrations (increase in LDL and decrease in HDL)
excessive tiredness
anxiety and depression
feelings of social isolation
reduction in 'quality of life'
increased sensitivity to cold or heat.
What is Hypopituitarism?
Hypopituitarism is a condition in which the pituitary gland does not produce one or more hormones in sufficient amounts. In some people, only a single hormone may be affected, while others may have deficiencies in several pituitary hormones.
The pituitary gland plays a vital role in regulating many of the body's essential functions, including growth, metabolism, reproduction, stress response, and water balance. When hormone production is reduced, a wide range of symptoms can occur depending on which hormones are affected.
The term "hypopituitarism" comes from the word hypo, meaning "under" or "below normal," and refers to reduced pituitary hormone production.
Which Hormones Can Be Affected?
Hypopituitarism may affect one or more of the hormones produced or controlled by the pituitary gland, including:
- Growth Hormone (GH) – important for growth, body composition, energy levels, and overall wellbeing.
- Luteinizing Hormone (LH) – involved in reproductive health and sex hormone production.
- Follicle-Stimulating Hormone (FSH) – plays a key role in fertility and reproductive function.
- Adrenocorticotropic Hormone (ACTH) – stimulates the adrenal glands to produce cortisol, which helps the body respond to stress.
- Thyroid-Stimulating Hormone (TSH) – regulates thyroid hormone production and metabolism.
- Arginine Vasopressin (AVP), also known as antidiuretic hormone (ADH) – helps regulate the body's fluid balance.
- Prolactin – involved primarily in breast development and milk production
What are the symptoms of Hypopituitarism ?
The symptoms of hypopituitarism vary depending on which hormones are deficient and the severity of the deficiency. Symptoms may develop gradually over time or occur more suddenly in certain situations.
Common symptoms can include:
- Persistent fatigue or low energy
- Unexplained weight changes
- Sensitivity to cold
- Reduced exercise tolerance
- Low mood or difficulty concentrating
- Changes in menstrual cycles
- Reduced fertility
- Loss of libido (sex drive)
- Erectile dysfunction in men
- Increased thirst and urination
- Muscle weakness
- Reduced quality of life and general wellbeing
Not everyone experiences the same symptoms. The type, number, and severity of symptoms can vary significantly from person to person. Some individuals may have only mild symptoms, while others may experience a greater impact on their daily lives.
Understanding which hormones are affected is an important step in diagnosing hypopituitarism and ensuring appropriate treatment and ongoing care.
What Causes Hypopituitarism?
Hypopituitarism can occur when the pituitary gland is damaged or unable to produce sufficient amounts of one or more hormones. There are several possible causes, and in some cases, more than one factor may contribute to the condition.
Common causes of hypopituitarism include:
Pituitary Tumours
The most common cause of hypopituitarism is a benign (non-cancerous) tumour of the pituitary gland, known as a pituitary adenoma. Although these tumours are usually not cancerous, they can affect normal pituitary function by compressing healthy pituitary tissue and reducing hormone production.
Pituitary Surgery or Radiotherapy
Treatment for pituitary tumours or other conditions affecting the pituitary gland may involve surgery and/or radiotherapy. While these treatments can be highly effective, they may also affect normal pituitary tissue and result in hormone deficiencies over time.
Pituitary Cysts
Fluid-filled cysts within or near the pituitary gland, such as Rathke's cleft cysts, can occasionally interfere with normal pituitary function by placing pressure on the gland.
Tumours Near the Pituitary Gland
Benign tumours that develop close to the pituitary gland, such as craniopharyngiomas, may affect hormone production by compressing the pituitary gland or the hypothalamus, which helps regulate pituitary function.
Traumatic Brain Injury
Moderate to severe head injuries can sometimes damage the pituitary gland or disrupt the connection between the pituitary gland and the hypothalamus. This may lead to partial or complete hormone deficiencies that can develop immediately after the injury or months later.
Other Causes
Less common causes of hypopituitarism include inflammatory and autoimmune conditions, infections, reduced blood supply to the pituitary gland, certain genetic disorders, and rare conditions affecting the hypothalamus.
Identifying the underlying cause of hypopituitarism is an important part of diagnosis and helps guide treatment and long-term management of the condition.