The human body has two adrenal glands, which are symmetrically placed in the trunk. They are located directly on top of each kidney. Adrenal glands are part of the endocrine system, a complex network of glands that produce hormones. Hormones are chemical transmitters of information. They respond to stimuli in the body by traveling to specific organs and interacting with receptor cells that detect their presence. Hormones tell various organs when to increase or decrease their participation in physiological functions such as metabolism, digestion and regulation of blood glucose levels.
Causes
Gary Thibodeau, author of the book "The Human Body in Health and Disease," explains that adrenal dysfunction can result from factors such as tumors, infection and disorders of the hypothalamus or pituitary gland. These disorders cause the production of adrenal hormone to increase or decrease to abnormal levels.
Tumors of the adrenal gland can result in a range of complications depending on which part of the adrenal gland they invade. Infections such as tuberculosis have been known to destroy adrenal gland tissue. Disorders of the pituitary gland and hypothalamus can disrupt their normal production of hormones that directly influence adrenal function.
Effects
The effects of adrenal disorders are a result of the fluctuations in adrenal hormone that they cause. When the adrenal hormone aldosterone is produced in abnormally high concentrations, the amount of sodium in the blood rises, causing a subsequent rise in blood pressure. When cortisol is increased it can cause a redistribution of fat that results in a moon-faced appearance and a fatty hump between the shoulders.
The adrenal gland also produces sex hormones. The Dartmouth-Hitchcock Medical Center states that an adrenal tumor that produces excess amounts of these hormones can result in the development of masculine characteristics in women, such as facial hair, and feminine characteristics in men, such as enlarged breasts.
Diagnosis
In order to reach a diagnosis of adrenal disorder, a doctor will perform a thorough physical examination and take a medical history of the patient. She may then order laboratory tests to detect the levels of adrenal hormone in the blood. Plasma cortisol, ACTH and testosterone are among the hormone blood levels that can be assessed when considering a diagnosis of adrenal disorder. Urine tests are also useful when assessing levels of cortisol, epinephrine and norepinephrine.
MRI scans of the brain may be used if pituitary or hypothalamic involvement is suspected. A high-resolution CT scan can assess the size and condition of the adrenal glands as well, according to the Merck Manuals Online Medical Library.
Treatment
The variety of conditions that fall under the category of adrenal disorders has an equally wide variety of treatment options. Treatments will depend on what specific adrenal hormone levels are elevated or depressed.
MayoClinic.com explains that the condition known as Addison's disease, wherein insufficient amounts of adrenal hormone are produced, is treated with hormone replacement therapy.
In cases of adrenal hypersecretion of hormones, adrenal inhibitor drugs are used to suppress excess hormone production.
Tumors of the adrenal gland are treated with surgery or radiation therapy.
Prognosis
Some adrenal disorders may never be cured but may be manageable through lifelong hormone replacement therapy. Conditions such as Addison's disease can be life-threatening if left untreated.
References
- "The Human Body in Health and Disease"; Gary Thibodeau, PhD, and Kevin Patton, PhD; 2002
- MayoClinic.com: Addison's Disease: Treatment and Drugs
- Merck Manuals Online Medical Library: Cushing's Syndrome
- Collin College: Anatomy/Physiology: Major Endocrine Organs
- Children's Hospital of Pittsburgh: Overactive Adrenal Glands/Cushing's Syndrome
