December 20, 2008 · 4 Comments
Cushing’s Syndrome results from excessive secretion of one or all of the adrenocortical hormones which includes glucocorticoid cortisol (predominant type), the mineralocorticoid aldosterone, and the adrogenital corticoids.
Types of Cushing’s Syndrome:
1. Pituitary Cushing’s syndrome (Cushing’s disease) is the most common cause of Cushing’s syndrome, and stems from hyperplasia of both adrenal glands caused by over stimulation by adrenocorticotropic hormone (ACTH), usually from pituitary adenoma. The syndrome mostly affects women between ages 20 and 40.
2. Adrenal Cushing’s syndrome is associated with adenoma or carcinoma of the adrenal cortex. The disease may recur after surgery.
3. Ectopic Cushing’s syndrome results from autonomous ACTH secretion by extrapituitary tumors (such as the lungs) producing excess ACTH.
4. Iatrogenic Cushing’s syndrome is caused by exogenous glucocorticoid administration.
1. Signs and symptoms of excess glucocorticoid (cortisol) secretion:
- Weight gain or obesity.
- Heavy trunk; thin extremities.
- Fat pad (Buffalo Hump) in neck and supraclavicular area.
- Rounded face (moon face); plethoric, oily complexion.
- Skin – fragile and thin; striae and ecchymosis, acne.
- Musculoskeletal – muscle wasting causes by excessive catabolism, osteoporosis, characteristic kyphosis, back ache.
- Mental disturbances – mood changes, psychosis.
- Increased susceptibility to infections.
2. Manifestation of excess mineralocorticoid (aldosterone) secretion:
- Hypernatremia, hypokalemia
- Weight gain
- Expanded blood volume
3. Manifestation of excess androgens:
- Females experience virilism (masculinization) with hirsutism (excessive growth of hair on the face and midline of trunk); atrophied breast, enlarged clitoris, masculinized voice, loss of libido, hermaphroditism (if exposed in utero).
- Males – loss of libido.
- Excessive plasma cortisol levels and loss of diurnal variation.
- Increased blood glucose levels, decreased serum potassium level.
- Plasma ACTH elevated in patients with pituitary tumors, very low in patients with adrenal tumor.
- Eosinophils decreased on complete blood count.
- Elevated urinary 17-hydroxycorticoids and 17-ketogenic steroids.
- Overnight dexamethasone suppression test, possibly with cortisol urinary excretion measurement, to check for:
- Unsuppressed cortisol level in Cushing’s syndrome cause by adrenal tumors.
- Suppressed cortisol level in Cushing’s disease caused by pituitary tumor.
- Skull X-ray detects erosion of the sella turcica by a pituitary tumor; CT scan and ultrasonography locate tumor.
- Pituitary surgery to treat pituitary Cushing’s syndrome.
- Transsphenoidal adenomectomy or hypophysectomy.
- Transfrontal craniotomy may be necessary when a pituitary tumor has enlarged beyond the sella turcica.
- Bilateral adrenalectomy is used to treat adrenal causes.
- Radiation therapy may also be used to treat pituitary or adrenal tumors.
- Monitor intake and output, daily weights, and serum glucose and electrolytes.
- Monitor for signs of infection because risk is high with excess glucocorticoids.
- After hypophysectomy, monitor for diabetes insipidus, hypothyroidism, and other endocrine changes.
- Assess the skin frequently to detect reddened areas, skin breakdown or tearing, excoriation, infection or edema.
- Handle skin and extremity gently to prevent trauma; prevent falls by using siderails.
- Avoid using adhesive tape on the skin to reduce trauma on its removal.
- Encourage the patient to turn in bed frequently or ambulate to reduce pressure on bony prominences and areas of edema.
- Assist the patient with ambulation and hygiene when weak and fatigued. Use assistive devices during ambulation to prevent falls and fractures.
- Help the patient to schedule exercise and rest. Advise the patient how to recognize signs and symptoms of excessive exertion.
- Instruct the patient to correct body mechanics to avoid pain or injury during activities.
- Provides foods low in sodium to minimize edema and provide foods high in potassium (bananas, orange juice, tomatoes) and administer potassium supplements as prescribed to counteract weakness re;ated to hypokalemia.
- Report edema and signs of fluid retention.
- Encourage the patient to verbalize concerns about the illness, changes in appearance, and alters role function.
- Explain to female patient who has benign adenoma or hyperplasia that, with proper treatment, evidence of masculinization can be reversed.