Addison disease also referred as hypocortisolism, chronic adrenal insufficiency, and hypoadrenalism, is a chronic disorder where the adrenal glands fail to produce sufficient steroid hormones – mineralcorticoids and glucocorticoids. The disease is characterized by various non-specific symptoms, such as weakness and abdominal pain, which may progress, under certain circumstances, to Addison crisis, a severe illness that include coma and low blood pressure. The condition is caused by damages in the immune system and arises from primary adrenal insufficiency of the adrenal gland. Addison disease, also known as chronic primary adrenocortical insufficiency, is usually diagnosed through medical imaging and blood tests. Treatment involves replacement of the absent hormones (oral fludrocortisone and hydrocortisone). Continuous steroid replacement therapy is necessary with regular monitoring and follow-up treatment for other health problems (Hahner 5).
The symptoms of Addison disease develop insidiously and, hence, take some time before they are noticed. The most common symptoms include lightheadedness, fatigue, muscle weakness, weight loss, fever, anxiety, difficulty in standing up, nausea, diarrhea, vomiting, sweating, headache, joint and muscle pains, and changes in personality and moods. There can also be cravings for salty food and salt because of sodium losses. Increased tanning is also notable, as well as darkening of friction sites, palmar creases, recent scars, genital skin and the vermilion border of the lips. This is not observable in tertiary and secondary hypoadrenalism (Arlt 4).
Clinical signs. Most patients diagnosed of primary Addison disease have darkened skin (hyperpigmentation) including areas, which are not exposed to the sun; characteristic locations of the lesion are nipples, skin creases, and inner side of the cheeks. In addition, old scars may darken as well. Hyperpigmentation takes place because adrenocorticotropic and melanocyte-stimulating hormones share a common precursor molecule, pro-opiomelanocortin (POMC). The POMC gets cleaved into beta-lipotropin, ACTH and gamma MSH after production in the anterior pituitary gland. Further cleavage of the subunit continues to produce alpha-ASH, which is the most influential MSH for skin pigmentation. Addison skin darkening does not take place in the secondary and tertiary forms. Medical conditions, such as thyroid disease, diabetes type 1 and vitiligo often take place in combination with Addison disease. Therefore, signs and symptoms of any of the former conditions may affect patients with Addison disease (Guinot et. al. 4).Want an expert to write a paper for you Talk to an operator now
Addisonian crisis. An Adrenal crisis or Addisonian crisis is a constellation of symptoms, which is an indication of severe adrenal insufficiency. It appears as a result of previously undiagnosed Addison disease or intercurrent problem of a patient. It is a life-threatening situation and a medical emergency requiring immediate treatment (Gurnell et. al.11).
- Low blood pressure
- Psychosis, confusion and slurred speech
- Severe diarrhea and vomiting, as a result of dehydration
- Severe lethargy
- Sudden penetrating pain in the abdomen, lower back or legs
- Syncope (loss of the ability to stand, which results in faint)
Causes. Causes of insufficiency of adrenalin are grouped by the manner in which they make adrenal glands produce insufficient level of cortisol. The causes are impaired steroidogenesis, adrenal dysgenesis or adrenal destruction. Adrenal dysgenesis is a genetic cause, which is usually extremely rare. It includes mutation in the congenital adrenal hypoplasia (CAH) because of mutations in the ACTH receptor gene and DAX-1 gene mutations. When DAX-1 is deleted together with other genes, DAX-1 mutation seems to cluster in a syndrome with deficiency in glycerol kinase. Impaired steroidogenesis is the interruption in the delivery of cholesterol, which is converted biochemically to steroid hormones. Adrenal destruction is the commonest cause of Addison condition in the industrialized world. Adrenal cortex autoimmune destruction is caused by immunoreactions against 21-hydrolase enzyme (Gurnell et. al.11).
Diagnosis. Low blood sugar, hypoglycemia is worse for children because of the loss of glucogenic effects of the glucocorticoids. Low blood sodium levels (Hyponatremia) are prevalent because of the inability of the kidney to excrete free water in the presence of cortisol insufficiency. In addition, this may also be caused by the effect of corticotrophin-releasing hormone, which stimulates the secretion of ADH. Moreover, Hyponatremia takes place in secondary adrenal insufficiency because of pituitary disease, where deficiency of aldosterone is not a feature. Raised blood potassium levels (Hyperkalemia) occur because of the loss of production of the aldosterone hormone. Increased blood acidity (metabolic acidosis) also occurs following the loss of the aldosterone hormone since sodium reabsorption in the distal tubule is connected with hydroxonium ion secretion. Sodium losses through the urine and retention of hydrogen ions in the serum result from low-level stimulation of aldosterone of the renals distal tubule (Gurnell et. al.11).
Testing. In case someone is suspected to have Addison disease, patients have to demonstrate low level of adrenal hormone, even after appropriate stimulation, which is known as the ACTH stimulation test with tetracosactide hormone, a synthetic pituitary ACTH. The process of testing is categorized into two types: short and long test. In the short test, blood cortisol levels are compared, and later 250 micrograms of tetracosactide (intravenous or intramuscular) are administered. An hour later, when plasma cortisol exceeds one-hundred-and-seventy nmol/l and has increased by at least three-hundred-and-thirty nmol/l, failure of the adrenal gland is excluded. When the test is abnormal, long test is recommended to differentiate between secondary adrenocortical insufficiency and primary adrenal insufficiency. The long test makes use of one milligram of tetracosactide, where blood is taken at an interval of one, four, eight and twenty four hours. 1000 nmol/l by four hours is the normal plasma cortisol level. The cortisol level, in primary Addison disease, is reduced at all stages while a delayed, but normal response is evident in secondary corticoadrenal insufficiency.
Various tests can be performed in order to distinguish between the causes of hypoadrenalism. It includes adrenocorticotropic and rennin hormone levels, as well as medical imaging, which is carried out typically in the computed tomography form, ultrasound or magnetic resonance imaging. In addition, adrenoleukodystrophy and adrenomyeloneuropathy may cause neurological symptoms, which are combined with adrenal insufficiency. These illnesses are estimated due to the cause of adrenal insufficiency in approximately thirty five percent male patients with idiopathic Addison disease. These results should be considered in the differential diagnosis of any male patient with adrenal insufficiency. Diagnosis involves a test of blood purposely for detecting long chains of fatty acids (Arlt et. al. 4).
Treatment. Treatment of the disease involves the replacement of the mission cortisol in the form of oral hydrocortisone tablets. Sometimes, such tablets may include prednisone in a dosing regimen, which mimics physiological concentrations of cortisol. As an alternative treatment, a quarter as much prednisoline may be administered for an equivalent effect of glucocorticoids, such as hydrocortisone. This treatment has to be continued for life. Further, a majority of patients may require aldosterone to be replaced by fludrocortisone. When patients, diagnosed of Addison disease, become ill following infection, or undergoing surgery as well as other trauma, caution must be exercised. In such circumstances, the replacement of glucocorticoids, whether in the form of prednisolone, hydrocortisone, prednisone, or other equivalent, must be increased. Hospital admission of patients may be necessitated, considering their inability to take oral medication, for the purposes of administering steroids intravenously. Patients with Addison are most often advised to be well-informed about their condition in order to aid personnel of emergency medical services in case if a need arises (Arlt 7).