The adrenal glands—small glands located above both kidneys—are composed of two separate regions: the medulla and the cortex.
The medulla produces the hormones that regulate the body’s reaction to stress. The medulla and produces epinephrine and norepinephrine, which are commonly called adrenaline and noradrenaline.
The cortex produces hormones that affect blood pressure and blood sugar levels, growth and some sexual characteristics. The cortex produces steroid hormones such as cortisol, aldosterone and testosterone.
The adrenal glands interact with the hypothalamus and pituitary gland. The hypothalamus produces hormones that stimulate the pituitary gland. In turn, the pituitary gland produces hormones that stimulate the adrenal glands to produce hormones.
In general, diseases of the adrenal glands cause the glands to become overactive or underactive - producing too much or not enough hormone.
About 3 percent of people have one or more nodules of the adrenal glands. In most cases, these growths are noncancerous. In about 10 percent of cases, nodules are more serious and cause an overproduction of certain hormones. In rare cases, an adrenal nodule is cancerous. The adrenal gland may also become enlarged.
Underactive Adrenal Gland Disorders
The adrenal glands may fail to produce adequate levels of cortisol for many reasons. The problem may be related to a disorder of the adrenal glands themselves or to inadequate secretion of adrenocorticotropic hormone by the pituitary gland. Symptoms of underactive adrenal glands include fatigue, weight loss, poor appetite, weakness and gastrointestinal problems.
Froedtert & the Medical College of Wisconsin endocrinologists are experienced in diagnosing and treating all disorders that result in underactive adrenal glands:
- Polyglandular autoimmune syndrome Type 1 and Type 2
- Primary adrenal insufficiency (Addison’s disease)
- Secondary adrenal insufficiency
- Congenital adrenal hyperplasia
Overactive Adrenal Gland Disorders
A tumor of the adrenal glands can result in the overproduction of various hormones.
Pheochromocytoma, a rare, usually benign, tumor of the adrenal glands resulting in the glands secreting excessive amounts of the hormones adrenaline and noradrenaline (catecholamines). This causes variable symptoms such as high blood pressure, sweating, headache, chest pain and anxiety. About 10 percent of these tumors are cancerous and have the potential to spread to other parts of the body. There may be a family history of this disease.
Primary hyperaldosteronism, also called aldosterone secreting adenoma or Conn’s syndrome, a condition in which too much of the hormone aldosterone is produced by the adrenal glands. This can lead to lower levels of potassium, in the blood. This condition, often caused by a tumor (adrenal cortical adenoma) in the adrenal glands, is one of the most common causes of secondary hypertension (high blood pressure). Up to 10 percent of people with high blood pressure have an unrecognized adrenal gland disorder.
Cushing’s syndrome, a disorder caused by prolonged exposure of the body’s tissues to high levels of the hormone cortisol. Pituitary disorders can lead to excess release of cortisol from the adrenal glands.
Diagnosing Adrenal Gland Disorders
Adrenal vein sampling (AVS) is a minimally invasive procedure to collect blood samples from the adrenal glands to determine how active the glands are and if one gland is more active than the other. Blood samples are collected through a catheter (thin tube) from each adrenal vein and also from an arm.
ACTH stimulation test for adrenal insufficiency measures the adrenal glands’ stress response to adrenocorticotropic hormone (ACTH). This hormone, produced in the pituitary gland, stimulates the adrenal glands to release cortisol. During the test, a small amount of synthetic ACTH is injected, and the amount of cortisol produced by the adrenal glands in response is measured. This test is used to diagnose or rule out primary and secondary adrenal insufficiency, Addison’s disease and related conditions.
Treatment of Adrenal Gland Disorders
Medical College of Wisconsin endocrinologists and surgeons work as a team to treat disorders of the adrenal glands.
Surgical options include:
- Laparoscopic adrenalectomy, a minimally invasive procedure to remove the adrenal glands
- Adrenal sparing surgery - removal of the tumor in the adrenal gland, while sparing normal adrenal tissue
Medical treatment options, including spironolactone/eplerenone and steroid hormone replacement, may also be prescribed.