Adrenal glands, which are also called suprarenal glands, are small, triangular glands located on top of both kidneys. An adrenal gland is made of two parts: the outer region, called the adrenal cortex, and the inner region, called the adrenal medulla. The adrenal glands work interactively with the hypothalamus and pituitary gland, as well as secrete hormones that affect metabolism, blood chemicals, and certain body characteristics. Adrenal glands also secrete hormones that help a person cope with both physical and emotional stress.
Hormones secreted by the adrenal glands include the following:
- Adrenal cortex
- Corticosteroid hormones (hydrocortisone or cortisol) help control the body's use of fats, proteins, and carbohydrates, suppress inflammatory reactions in the body, and affect the immune system function
- Aldosterone inhibits the level of sodium excreted into the urine, and maintains blood volume and blood pressure
- Androgenic steroids (androgen hormones) have an effect on the development of male characteristics
- Adrenal medulla
- Epinephrine (adrenaline) increases the heart rate and force of heart contractions, facilitates blood flow to the muscles and brain, causes relaxation of smooth muscles, helps with conversion of glycogen to glucose in the liver, and other activities
- Norepinephrine (noradrenaline) has little effect on smooth muscle, metabolic processes and cardiac output, but has strong vasoconstrictive effects (narrowing of the blood vessels), thus, increasing blood pressure
Certain adrenal gland disorders are characterized by an inability of the adrenal glands to produce cortisol (also known as hydrocortisone hormone) and aldosterone, often due to certain missing enzymes (proteins that speed up or cause chemical reactions). The result is enlarged adrenal glands due to overstimulation from the hypothalamus, which detects the low levels of hormones. The hypothalamus, in turn, stimulates the pituitary gland to stimulate the adrenal glands. Overstimulation of the adrenal glands can lead to overproduction of androgens, which can lead to masculinization. Disorders of the adrenal glands require clinical care by a physician or other healthcare professional.
Underactive Adrenal Glands / Addison's DiseaseWhat is Addison's disease?
Addison's disease is the result of an underactive adrenal gland. An underactive adrenal gland produces insufficient amounts of cortisol (a steroid hormone that helps to control the body's use of fats, proteins and carbohydrates, suppresses inflammatory reactions in the body, and affects immune system functions) and aldolsterone (a steroid hormone that controls sodium and potassium in the blood). One in every 100,000 people have Addison's disease. Onset of the disease may occur at any age.
What causes Addison's disease?
Most of the time, the cause of the disease is unknown (idiopathic). About one-third of Addison's disease cases are caused by the actual destruction of the adrenal glands through cancer, infection, an autoimmune process, or other diseases. Other causes may include:
- Use of corticosteroids as a treatment (such as prednisone) may cause a slowdown in production of natural corticosteroids by the adrenal glands
- Certain medications used to treat fungal infections may block production of corticosteroids in the adrenal glands
- Rarely, Addison's disease is inherited as an X-linked trait where the gene responsible for the condition is located on the X chromosome and passed down from a healthy female carrier to her sons (50/50 chance), who are affected. In this form, symptoms typically begin in childhood or adolescence.
What results from inadequate corticosteroid production?
Lack of adrenal hormones may cause:
- Elevated levels of potassium
- Extreme sensitivity to the hormone insulin, which normally is present in the bloodstream, and may lead to low blood sugar levels
- Increased risk during stressful periods, such as surgery, infection, or injury
What are the symptoms of Addison's disease?
Mild Addison's disease symptoms may only be apparent when the child is under physical stress. The following are the most common symptoms of Addison's disease. However, each child may experience symptoms differently.
- Rapid pulse
- Dark skin (first noted on hands and face)
- Black freckles
- Bluish-black discoloration around the nipples, mouth, rectum, scrotum, or vagina
- Weight loss
- Loss of appetite
- Intense salt craving
- Muscle aches
- Intolerance to cold
If not treated, Addison's disease may lead to severe abdominal pain, extreme weakness, low blood pressure, kidney failure, and shock - especially when the child is experiencing physical stress. The symptoms of Addison's disease may resemble other problems or medical conditions. Always consult your child's physician for a diagnosis.
How is Addison's disease diagnosed?
In addition to a complete medical history and physical examination, diagnostic procedures for Addison's disease may include blood tests to measure corticosteroid hormone levels.
Treatment of Addison's disease
The goal of treatment is to restore the adrenal glands to normal function, producing normal levels of corticosteroid hormones. Since Addison's disease can be life threatening, treatment often begins with administration of corticosteroids. Corticosteroids, such as prednisone, may be taken orally or intravenously, depending on the child's condition. Usually the child must continue taking the corticosteroids for the rest of his/her life. Treatment may also include taking a medication that helps restore the body's level of sodium and potassium.
Overactive Adrenal Glands / Cushing's SyndromeWhat are overactive adrenal glands?
When adrenal glands produce excessive amounts of certain hormones, they are called overactive. Symptoms and treatment depend on which hormones are being overproduced, including the following:
- Androgenic steroids (androgen hormones) - an overproduction of androgenic steroids (such as testosterone) can lead to exaggerated male characteristics in both men and women, such as excess hair on the face and body, baldness, acne, deeper voice, and increased muscle mass. If a female fetus is exposed to high levels of androgens early in pregnancy, her genitals may develop abnormally. Young boys who experience high levels of androgen levels may grow faster, but bones may also mature faster and stop growing too soon.
- Corticosteroids - an overproduction of corticosteroids can lead to Cushing's syndrome.
- Aldosterone - an overproduction of the aldosterone hormone can lead to high blood pressure and to those symptoms associated with low levels of potassium (i.e., weakness, muscle aches, spasms, and, sometimes, paralysis.)
The symptoms of overactive adrenal glands may resemble other problems or medical conditions. Always consult your child's physician for a diagnosis.
How are overactive adrenal glands diagnosed?
In addition to a complete medical history and physical examination, diagnostic procedures to measure levels of hormones for overactive adrenal glands may include:
- Specific blood tests
- Urine tests
Treatment of overactive adrenal glands
Treatment of overactive adrenal glands depends on the cause of the disease. Specific treatment for overactive adrenal glands will be determined by your child's physician based on:
- Your child's age, overall health, and medical history
- Extent of the disease
- Your child's tolerance for specific medications, procedures, or therapies
- Expectations for the course of the disease
- Your opinion or preference
Treatment may include surgical removal of growths on the adrenal gland(s), or the adrenal gland(s) itself. Medications that block the excessive production of certain hormones may also be administered.
What is Cushing's syndrome?
Cushing's syndrome is myriad abnormalities that are the result of hypersecretion of corticosteroids by the adrenal cortex. An overproduction of cortisol, the hormone that controls the adrenal gland may be one cause. In addition, certain lung cancers and other tumors outside the pituitary gland may produce corticotropins. Other causes include benign (non-cancerous) or cancerous tumors on the adrenal glands. Cushing's syndrome is rare in children and more commonly seen in adults.
What are the symptoms of Cushing's syndrome?
The following are the most common symptoms of Cushing's syndrome. However, each child may experience symptoms differently. Children and adolescents with Cushing's syndrome primarily experience weight gain, growth retardation, and hypertension (high blood pressure).
- Upper body obesity
- Round or moon-shaped face
- Increased fat around neck
- Thinning arms and legs
- Fragile and thin skin
- Darkened pigmentation of the skin
- Stretch marks on abdomen, thighs, buttocks, arms, and breasts
- Bone and muscle weakness
- Severe fatigue
- High blood sugar
- Irritability and anxiety
- Excessive hair growth in females
- Irregular or stopped menstrual cycles in females
- Reduced sex drive and fertility in males
The symptoms of Cushing's syndrome may resemble other conditions or medical problems. Always consult your child's physician for a diagnosis.
How is Cushing's syndrome diagnosed?
In addition to a complete medical history and physical examination, diagnostic procedures for Cushing's syndrome may include:
- 24-hour urinary test(urine is collected over a 24-hour period to measure for corticosteroid hormones)
- Computed tomography scan(CT scan)
- Magnetic resonance imaging (MRI)
- Dexamethasone suppression test(to differentiate whether the excess production of corticotropins are from the pituitary gland or tumors elsewhere)
- Corticotropin-releasing hormone(CRH) stimulation test(to differentiate whether the cause is a pituitary tumor or an adrenal tumor)
Treatment for Cushing's syndrome
Treatment for Cushing's syndrome depends on its cause. Surgery may be needed to remove tumors of the adrenal glands.
What is a pheochromocytoma?
A pheochromocytoma is an adrenal gland tumor that secretes epinephrine and norepinephrine hormones. These hormones are responsible for regulating heart rate and blood pressure, among other functions. Pheochromocytomas occur most frequently in young to middle-aged adults between the ages of 30 and 60. Ten percent of individuals affected are children who usually develop symptoms between the ages of 6 and 14.
What causes pheochromocytomas?
The causes of pheochromocytoma are multifactorial. In most cases, both genetic and environmental factors play a role. The condition can occur alone or in combination with other disorders. The following are the most common disorders associated with pheochromocytoma:
- Von Hippel-Lindau disease
- Multiple endocrine neoplasia(MEN) syndromes
- Tuberous sclerosis
- Sturge-Weber syndrome
- A taxia-telangiectasia
What are the symptoms of pheochromocytoma?
The most common symptom of pheochromocytoma is high blood pressure, which is sometimes extreme. Each child may experience symptoms differently.
- Rapid pulse
- Heart palpitations
- Poor weight gain despite good appetite
- Growth failure
- Abdominal pain
- Pale skin
- Clammy skin
The symptoms of pheochromocytoma may resemble other problems or medical conditions. Always consult your child's physician for a diagnosis.
How is pheochromocytoma diagnosed?
In addition to a complete medical history and physical examination, diagnostic procedures for pheochromocytoma may include:
- Blood and urine tests (to measure hormone levels)
- Computed tomography scan (CT scan)
- Radioisotope scan - uses radioactive substances introduced into the body to create an image of the functioning adrenal gland.
Treatment for pheochromocytoma usually includes removing the tumor. Before removing the tumor, however, your child's physician may prescribe medications to control high blood pressure. In children, there may be multiple tumors. An extensive evaluation to locate them will be required before surgery.
Continuous medical follow-up may be required to monitor the development of future tumors.
Family members may also want to consider testing to rule out the presence of the tumors, as genetics does appear to play a role in some cases.