27
Signs and Symptoms
Clinical manifestations of this condition include weakness, nausea, abdominal pain,
vomiting, and dehydration. Some historical evidences, such as the tan skin of a
patient refusing to receive sunlight, may specify chronic adrenal insufficiency.
Adrenal insufficiency along with hypotension is called the adrenal crisis and institutes real life-threatening crises [45].
Chronic Adrenal Insufficiency
Adrenal insufficiency results from inability of adrenal cortex to release cortisol in an
adequate amount. It can be classified as primary, secondary, or tertiary which is dependent on either cortex is damaged directly or indirectly. Addison’s disease (primary adrenal insufficiency) is a metabolic as well as endocrine disease resulting from direct injury
or failure of the adrenal cortex. This is a chronic ailment having a long-term attack.
Primary adrenal insufficiency may occur whenever there is a direct damage to adrenal
cortex, i.e., adrenal hemorrhage, autoimmune diseases, tuberculosis (infectious diseases), meningococcemia pathophysiology, and acquired immunodeficiency syndrome
(AIDS) [46]. As mentioned earlier, the adrenal cortex secretes the corticosteroids aldosterone and cortisol. Aldosterone is responsible for maintaining a balance of serum levels of potassium and sodium. Whenever body is under any stress (such as trauma, heart
ischemia, infection, or serious illness), the adrenal gland may not be able to produce
adequate amount of corticosteroids to meet the body’s needs, causing acute exacerbations of Addison’s disease. Although in secondary adrenal insufficiency, the cortex itself
remains intact, since the pituitary does not release the adrenal cortex hormone (ACTH),
which normally stimulates the adrenal cortex, the pituitary does not release cortisol,
hence adrenal insufficiency is one step lesser. Therefore, adrenal insufficiency is a step
removal. The reason for the third-level (tertiary) adrenal insufficiency is more direct,
because the pituitary cannot release ACTH because of pituitary hypothalamic disease
[47]. Primary adrenal insufficiency may include hyperpigmentation due to excessive
production of melanocyte stimulating hormone (MSH) which is due to the reason that
both MSH and ACTH are secreted by the single precursor protein in the pituitary named
pro-opiomelanocortin. MSH is responsible for stimulating melanocytes for the production of melanin. Secondary and tertiary adrenal insufficiency are associated with
decreased levels of MSH so cannot be connected with hyperpigmentation of skin [46].
Signs and Symptoms
Signs and symptoms of Addison’s disease are mostly associated with the endocrine
and electrolyte disturbances which are characteristic of this disease. Due to excessive MSH, the patient will experience loss of appetite, weight loss, weakness,
chronic fatigue, and hyperpigmentation of the skin and mucous membranes. Patients
may experience electrolyte disturbances accompanying hyperkalemia,
1 Physiology of Endocrine System and Related Metabolic Disorders
Signs and Symptoms
Clinical manifestations of this condition include weakness, nausea, abdominal pain,
vomiting, and dehydration. Some historical evidences, such as the tan skin of a
patient refusing to receive sunlight, may specify chronic adrenal insufficiency.
Adrenal insufficiency along with hypotension is called the adrenal crisis and institutes real life-threatening crises [45].
Chronic Adrenal Insufficiency
Adrenal insufficiency results from inability of adrenal cortex to release cortisol in an
adequate amount. It can be classified as primary, secondary, or tertiary which is dependent on either cortex is damaged directly or indirectly. Addison’s disease (primary adrenal insufficiency) is a metabolic as well as endocrine disease resulting from direct injury
or failure of the adrenal cortex. This is a chronic ailment having a long-term attack.
Primary adrenal insufficiency may occur whenever there is a direct damage to adrenal
cortex, i.e., adrenal hemorrhage, autoimmune diseases, tuberculosis (infectious diseases), meningococcemia pathophysiology, and acquired immunodeficiency syndrome
(AIDS) [46]. As mentioned earlier, the adrenal cortex secretes the corticosteroids aldosterone and cortisol. Aldosterone is responsible for maintaining a balance of serum levels of potassium and sodium. Whenever body is under any stress (such as trauma, heart
ischemia, infection, or serious illness), the adrenal gland may not be able to produce
adequate amount of corticosteroids to meet the body’s needs, causing acute exacerbations of Addison’s disease. Although in secondary adrenal insufficiency, the cortex itself
remains intact, since the pituitary does not release the adrenal cortex hormone (ACTH),
which normally stimulates the adrenal cortex, the pituitary does not release cortisol,
hence adrenal insufficiency is one step lesser. Therefore, adrenal insufficiency is a step
removal. The reason for the third-level (tertiary) adrenal insufficiency is more direct,
because the pituitary cannot release ACTH because of pituitary hypothalamic disease
[47]. Primary adrenal insufficiency may include hyperpigmentation due to excessive
production of melanocyte stimulating hormone (MSH) which is due to the reason that
both MSH and ACTH are secreted by the single precursor protein in the pituitary named
pro-opiomelanocortin. MSH is responsible for stimulating melanocytes for the production of melanin. Secondary and tertiary adrenal insufficiency are associated with
decreased levels of MSH so cannot be connected with hyperpigmentation of skin [46].
Signs and Symptoms
Signs and symptoms of Addison’s disease are mostly associated with the endocrine
and electrolyte disturbances which are characteristic of this disease. Due to excessive MSH, the patient will experience loss of appetite, weight loss, weakness,
chronic fatigue, and hyperpigmentation of the skin and mucous membranes. Patients
may experience electrolyte disturbances accompanying hyperkalemia,
1 Physiology of Endocrine System and Related Metabolic Disorders