Addison Disease and Cushing's Syndrome

Addison Disease and Cushing's Syndrome

Introduction

The adrenal glands consist of a pair gland which functions in the production of hormones. On the basis of appearance, these glands are -triangular in shape; and reside on top of each kidney. The fundamental function of the adrenal glands is the production of hormones which regulate various processes of the human physiology. These hormones are (Rakel, 2012), 1. Glucocorticoids (e.g., cortisol), function to control the blood sugar level, blood pressure, process of fat and protein metabolism, and immunity (Charmandari, 2010). 2. Mineralocorticoids (e.g., aldosterone), function to control the renal and cardiovascular processes, such as homeostasis of salt and water level in the body (Farman, 2001). 3. Catecholamine (e.g., epinephrine), function in the maintenance of the “fight or flight” reaction whenever human body undergoes stress (Arun, 2006). 4. Adrenal androgens (e.g., dehydroepiandrosterone) mediate the production of sex hormones, which include testosterone and estrogen (Gurnell, 2008). An impairment in the functioning of the adrenal glands can cause two major disease known as, Addison's disease and Cushing's syndrome, which can be fatal if not managed timely (Pivonello, 2008).

Pathophysiology

Addison's disease

In Addison's disease, the normal functioning of the adrenal cortex gradually decreases, which causes lack of both glucocorticoid and mineralocorticoid hormones, and sometimes even DHEA and androgens hormones are deficit (Nieman, 2006). The progressive decline in the normal function of the adrenal can occur due to adrenal deficiency or reduced manufacture of adrenal hormones. Some of the factors of reduced production are,

Autoimmune

In this disorder, the body's internal immune system acts against the adrenal glands (Betterle, 2002).



Genetic

The inability of the human body to react to adrenocorticotropic hormone (ACTH) due to mutation of specific genes can ultimately cause slow development of the adrenal glands. This can result to decreased levels of secretion of adrenal hormones (Ten, 2001). Some individuals are born with genetic mutations and fail to produce all 3 types of the adrenal cortex hormones—glucocorticoids, mineralocorticoids, and androgens (Ten 2001).

Drugs

The process of adrenal hormone manufacture can also be inhibited due to the administration of certain drugs, which inhibit the production of steroids in the adrenal cortex. These drugs include, antifungal, such as miconazole, and ketoconazole (Hahner, 2010).

Tumors

Pituitary or hypothalamic tumors, pituitary surgery or radiation therapy can also impair the production of adrenal hormones because the adrenal glands are mediated by the hypothalamus and pituitary gland. Therefore, any condition that affects these areas of the brain can cause a reduction in normal adrenal function (Betterle 2002).

Others

Other causes or diseases which can cause impaired adrenal functioning are tuberculosis, cancer, or adrenal hemorrhage. (Ten, 2001; Betterle, 2002).

Cushing's syndrome

Cushing's disease occurs when the adrenocorticotropic hormone mediates the adrenal glands to manufacture cortisol, therefore; it there is surplus secretion of ACTH, and then it ultimately causes the disproportionate increase in the cortisol levels. Pituitary gland tumor causes the excessive release of cortisol (Yaneva, 2010). Cushing's disease is much different from the Cushing's syndrome. The abnormal secretion of ACTH due ...