Cushing's syndrome results from excessive cortisol production and leads to central obesity, high blood sugar, thin skin that bruises easily, and muscle wasting. It is typically caused by pituitary tumors or excess cortisol medications. Diagnosis involves tests of cortisol levels in blood and urine along with imaging scans to locate tumors. Treatment depends on the cause, with pituitary tumors removed surgically or radiated and adrenal tumors removed by adrenalectomy.

2. CUSHING’S SYNDROME
 Cushing’s syndrome results from excessive, rather than deficient,
adrenocortical activity.
 The syndrome may result from excessive administration of
corticosteroids or ACTH or from hyperplasia of the adrenal cortex.

3. Clinical Manifestations
 When overproduction of the adrenal cortical hormone occurs, arrest of
growth, obesity, and musculoskeletal changes occur along with
glucose intolerance.
 The classic picture of Cushing’s syndrome in the adult is that of
central-type obesity, with a fatty “buffalo hump” in the neck and
supraclavicular areas, a heavy trunk, and relatively thin extremities.
 The skin is thin, fragile, and easily traumatized; ecchymoses (bruises)
and striae develop.

4.  The patient complains of weakness.
 Sleep is disturbed because of altered diurnal secretion of cortisol.
 Excessive protein catabolism occurs, producing muscle wasting and
osteoporosis.
 Kyphosis, backache, and compression fractures of the vertebrae may
result.
 Retention of sodium and water occurs as a result of increased
mineralocorticoid activity, producing hypertension and heart failure.

5.  The patient develops a “moon-faced” appearance and may experience
increased oiliness of the skin and acne.
 There is increased susceptibility to infection.
 Hyperglycemia or overt diabetes may develop.
 The patient may also report weight gain, slow healing of minor cuts,
and bruises.

6.  Women ages 20 to 40 years are five times more likely than men to
develop Cushing’s syndrome.
 In females of all ages, virilization may occur as a result of excess
androgens.
 Virilization is characterized by the appearance of masculine traits and
the recession of feminine traits.
 There is an excessive growth of hair on the face (hirsutism), the breasts
atrophy, menses cease, and the voice deepens.
 Libido is lost in men and women.

7.  Changes occur in mood and mental activity; psychosis may develop.
 Distress and depression are common and are increased by the severity
of the physical changes that occur with this syndrome.
 If Cushing’s syndrome is a consequence of pituitary tumor, visual
disturbances may occur because of pressure of the growing tumor on
the optic chiasm.

8. woman with Cushing’s
syndrome has several classic
signs, including
facial hair, buffalo hump, and
moon face.

9. Assessment and Diagnostic Findings
 Indicators of Cushing’s syndrome include an increase in serum
sodium and blood glucose levels and a decreased serum concentration
of potassium, a reduction in the number of blood eosinophils, and
disappearance of lymphoid tissue.
 Measurements of plasma and urinary cortisol levels are obtained.

10.  An overnight dexamethasone suppression test is the most widely used
screening test for diagnosis of pituitary and adrenal causes of
Cushing’s syndrome.
 Dexamethasone (1 mg) is administered orally at 11 pm, and a plasma
cortisol level is obtained at 8 the next morning.
 Suppression of cortisol to less than 5 mg/dL indicates that the
hypothalamic-pituitary-adrenal axis is functioning properly.

11.  Stress, obesity, depression, and medications such as antiseizure agents,
estrogen, can falsely elevate cortisol levels.
 Other diagnostic studies include a 24-hour urinary free cortisol level
and a high-dose or low-dose dexamethasone suppression test.
 High-dose and low-dose suppression tests are similar to the overnight
test but vary in dosage and timing.

12.  Measurement of plasma ACTH by radioimmunoassay is used in
conjunction with the high-dose suppression test to distinguish
pituitary tumors from ectopic sites of ACTH production as the cause of
Cushing’s syndrome.
 Elevation of both ACTH and cortisol level indicates pituitary or
hypothalamic disease.
 Low ACTH with a high cortisol level indicates adrenal disease.
 CT scan, ultrasound, or MRI may be performed to localize adrenal
tissue and detect tumors of the adrenal gland.

13. Medical Management
 If Cushing’s syndrome is caused by pituitary tumors rather than
tumors of the adrenal cortex, treatment is directed at the pituitary
gland.
 Surgical removal of the tumor by Transsphenoidal hypophysectomy.
 Radiation of the pituitary gland also has been successful, although it
may take several months for control of symptoms.
 Adrenalectomy is the treatment of choice in patients with primary
adrenal hypertrophy.

14.  Postoperatively, symptoms of adrenal insufficiency may begin to
appear 12 to 48 hours after surgery because of reduction of the high
levels of circulating adrenal hormones.
 Temporary replacement therapy with hydrocortisone may be
necessary for several months until the adrenal glands begin to respond
normally to the body’s needs.

15.  If both adrenal glands have been removed (bilateral adrenalectomy),
lifetime replacement of adrenal cortex hormones is necessary.
 Thanking you.