Cushing's Syndrome

Question 1

Define Cushing’s syndrome.

Answer 1

Cushing’s syndrome is caused by excessive steroids in the body. This may be due to many different causes such as a pituitary adenoma secreting too much ACTH or exogenous steroids from medication.

Question 2

Explain the aetiology/risk factors of Cushing’s syndrome.

Answer 2

Exogenous corticosteroid use
Pituitary adenoma
Adrenal adenoma
Adrenal carcinoma

Question 3

Summarise the epidemiology of Cushing’s syndrome.

Answer 3

Cushing syndrome is relatively uncommon in the general population. However, newer studies of high-risk groups report a significantly greater prevalence. Hypercortisolism has been reported in 0.5% to 1% of patients with hypertension, 2% to 3% of patients with uncontrolled diabetes, 6% to 9% of patients with adrenal masses, and 11% of patients with osteoporosis and vertebral fractures.

Question 4

Recognise the presenting symptoms of Cushing’s syndrome. Recognise the signs of Cushing’s syndrome on physical examination.

Answer 4

“Moon” Round face
Interscapular fat pad
Centripetal obesity
Striae
Menstrual irregularities

Question 5

Identify appropriate investigations for Cushing’s syndrome and interpret the results.

Answer 5

9am cortisol
High dose dexamethasone suppression test
Low dose dexamethasone suppression test
24 hour urinary free cortisol

Question 6

Generate a management plan for Cushing’s syndrome.

Answer 6

Reduce exogenous steroids
Transsphenoidal hypophysectomy
Bilateral adrenalectomy

The treatment depends on the cause of the Cushing’s.

Question 7

Identify the possible complications of Cushing’s syndrome and its management.

Answer 7

Adrenal insufficiency secondary to adrenal suppression
Cardiovascular disease
Hypertension
Diabetes mellitus
Osteoporosis
Nephrolithiasis
Hypopituitarism

Question 8

Summarise the prognosis for patients with Cushing’s syndrome.

Answer 8

Untreated disease carries a dismal survival rate of 50% at 5 years.

Within the first year of effective therapy, many of the characteristic features will resolve or show marked improvement.

Despite improvement of complications in most patients, cardiovascular risk, hypertension, obesity, and decreased quality of life may persist in some patients even after biochemical cure.