Pathophysiology of the Adrenal Cortex PDF

Pathophysiology of the Adrenal Cortex Pathophysiology of the Adrenal Cortex HIGH CORTISOL LOW CORTISOL  Addisons Disease: Primary Adrenal insufficiency  Primary Hypercortisolism  (Cushing’s Syndrome) ◦ Adrenal gland tumor (30% of cases) ◦ Low ACTH levels - Endogenous ◦ Low Cortisol/ High ACTH lev...

Pathophysiology of the Adrenal Cortex Pathophysiology of the Adrenal Cortex HIGH CORTISOL LOW CORTISOL  Addisons Disease: Primary Adrenal insufficiency  Primary Hypercortisolism  (Cushing’s Syndrome) ◦ Adrenal gland tumor (30% of cases) ◦ Low ACTH levels - Endogenous ◦ Low Cortisol/ High ACTH levels (Autoimmune or idiopathic) ◦ Adrenal antibodies present +/- ◦ More common in older women   Seconday Hypercortisolism  (Cushing’s Disease) ◦ Pituitary tumor (70% of cases) Secondary Adrenal Insufficiency (Hypopituitarism) ◦ Low ACTH and Low Cortisol (Trauma / benign tumor) ◦ High ACTH  High Cortisol  Iatrogenic Cushing’s Syndrome ◦ High Cortisol / Low ACTH ◦ Stopping Meds vs. Steroid taper Addisons Disease - LOW CORTISOL  Primary Adrenocortical Insufficiency  Autoimmune Disease (Adrenal antibodies present)  Destruction of all zones of the adrenal cortex  Decreased circulating levels of cortisol, aldosterone, and adrenal androgens ◦ Adrenal insufficiency occurs when at least 90 percent of the adrenal cortex has been destroyed. Symptoms of Addison Disease  The loss of glucocorticoids (cortisol) ◦ hypoglycemia, anorexia, weight loss, nausea and vomiting, and weakness  The loss of mineralocorticoids (aldosterone) ◦ hyperkalemia, metabolic acidosis, and hypotension due to decreased ECF volume  In women, the loss of the adrenal androgens, ◦ results in decreased pubic and axillary hair and decreased libido Symptoms of Addison Disease Hypoglycemia  Anorexia, Weight loss,  Nausea, vomiting  Weakness  Hypotension (postural)  Hyperkalemia  Metabolic acidosis    Hyperpigmentation (α-MSH fragment) Decreased pubic and axillary hair in females Addison’s Disease  ACTH Levels  Increased  (Decrease cortisol initiates a “feed forward” mechanism)  Cortisol Levels  Decreased ◦ Autoimmune- Disorder  Adrenal antibodies present +/-  More common in older women  Treatment ◦ Replacement of glucocorticoids and mineralocorticoids X Secondary Adrenal Insufficiency  Adrenal insufficiency due to a lack of ACTH ◦ (Low ACTH  Low Cortisol)   Head trauma -pituitary's inability to release ACTH secondary to head trauma Adenomectomy - Surgical removal of ACTH-producing tumors  Low ACTH and Low Cortisol  Stopping Corticosteroid Medication Abruptly! ◦ Failing to comply with a medically prescribed steroid taper X Addisonian Crisis – Medical Emergency  An endocrinologic emergency with a high mortality rate secondary to physiologic derangements from an acute deficiency of the adrenal hormone cortisol ◦ ◦ ◦ ◦ ◦ ◦ Dehydration Low blood pressure Salt craving Loss of consciousness Severe vomiting and diarrhea Sudden penetrating pain in the lower back, abdomen, or legs Cushing's Disease & Cushing Syndrome Cushing's Disease – Pituitary Tumor  Cushing's Disease is the result of hypersecretion of ACTH from a pituitary adenoma.  The elevated ACTH results in the secretion of excess amount of the glucocorticoid cortisol. Cushing Syndrome – Adrenal Tumor  Cushing’s Syndrome is caused excess secretion of cortisol from an adrenal gland tumor (30% of cases)  The signs and symptoms of either Cushing syndrome or Cushing disease can be the same. Both are the result of excessive glucocorticoids / excess cortisol. Symptoms of Cushing's Disease / Syndrome Hyperglycemia  Muscle wasting /Central obesity  Round face /Buffalo hump/  Osteoporosis  Hypertension  Menstrual disorders in females  Striae - dermal scarring associated with  stretching of the dermis, often result from a rapid change in weight Cushing Presntation Associated Symptoms  Hypertension occurs because cortisol has weak mineralocorticoid activity and because cortisol increases the responsiveness of arterioles to catecholamines (by up-regulating α receptors) 1  In biological females - excess androgens cause virilization and menstrual disorders in females Trunkal obesity / Purpal striae Etiology  Cushing’s Disease - ACTH ◦ Primary defect is in the anterior pituitary, which is overproducing ACTH; ACTH levels are elevated  Cushing Syndrome - Cortisol ◦ The primary defect is in the adrenal cortex, which is overproducing cortisol. Accordingly, ACTH levels are low because the high cortisol levels feed back on the anterior pituitary and inhibit ACTH secretion. Adrenal Androgens – In Females / Males  In females, the adrenal cortex is the major source of androgenic compounds.  In females, DHEA and androstenedione are responsible for the development of pubic and axillary hair and for libido.  The adrenal androgens do not have a significant biological effect in males as testosterone is a more potent androgen. Last Major League Baseball pitcher to win 30 or more games during a season (with a record of 31–6) - 1968 79 Prescribed Corticosteroids Stopping Corticosteroid Medication Abruptly!    A course of oral corticosteroid (i.e prednisone) is prescribed as a tapered dose.  Prednisone Withdrawal It is vitally important that a client completes the entire course as prescribed. Severe fatigue Weakness Body aches Joint pain Nausea Loss of appetite Lightheadedness Irritability or mood swings Failing to take the taper as prescribed can result in prednisone withdrawal