Clinical Syndromes of ACTH

Question 1

Cushing syndrome vs disease

Answer 1

Syndrome: chronic GC excess
Disease: specific type of Cushing syndrome due to excessive pituitary ACTH secretion from a pituitary tumor

Question 2

3 ways to classify Cushing syndrome

Answer 2

ACTH-dependent
ACTH-independent
Pseudo-Cushing syndrome

Question 3

Clinical features of Cushing syndrome

Answer 3

Obesity
HTN
Skin: Plethora, hirsutism, striae, acne, bruising
MSK: osteopenia, weakness
Neuropsychiatric: emotional lability, euphoria, depression, psychosis
Gonads: menstrual disorders, impotence, decreased libido
Metabolic: glucose intolerance, diabetes, hyperlipidemia, polyuria, kidney stones

Question 4

3 steps in diagnosis Cushing syndrome

Answer 4

Clinical suspicion
Confirmation of hypercortisolism
Localization of the cause

Question 5

3 tests to confirm hypercortisolism

Answer 5

1 mg overnight dexamethasone suppression test
Measurement of 24hr UFC in 2 or 3 collections (urine)
Measurement of midnight salivary cortisol levels

Question 6

2 tests for DDx of ACTH-dependent Cushing’s syndrome

Answer 6

Cranial MRI study

Bilateral simultaneous inferior petrosal sinus ACTH sampling

Question 7

1 test for DDx of ACTH independent Cushing’s syndrome

Answer 7

Abdominal MRI or CT scan

Question 8

Treatment of Cushing Syndrome

Answer 8

Surgery: pituitary, ectopic, adrenal
Medical: ketoconazole, metyrapone

Question 9

Adrenal insufficiency definition

Answer 9

Clinical condition that results from deficient production or action of GCs
With or without deficiency in mineralocorticoids and adrenal androgens

Question 10

Most common cause of primary adrenal insufficiency

Answer 10

Autoimmune adrenalitis (Addison’s)

Question 11

3 general causes of secondary adrenal insufficiency

Answer 11

Space occupying lesion or trauma
Genetic disorders
Drugs (long term GC use is the most common cause)

Question 12

Causes of tertiatry adrenal insufficiency

Answer 12

Hypothalamic tumours
Hypothalamic surgery/irradiation
Infections or infiltrative processes
Trauma, injury

Question 13

Common signs/symptoms of adrenal insufficiency

Answer 13

Fatigue, lack of energy or stamina, reduced strength
Anorexia, weight loss
Gastric pain, nausea, vomiting
Skin hyperpigmentation
Low BP, postural hypotension, dehydration

Question 14

Clinical features of acute adrenal crisis

Answer 14

Fever
Nausea, vomiting, anorexia
Weakness, apathy, depressed mentation
Hypoglycemia
Dehydration, volume depletion
Hypotension and shock

Question 15

3 main aims in the diagnosis of adrenal insufficiency

Answer 15

To confirm inappropriately low cortisol secretion
To find out whether the adrenal insufficiency is primary or central
To delineate the underlying pathological process

Question 16

Insulin Tolerance test (insulin induced hypoglycemia)

Answer 16

Useful in patients with suspected corticotropin deficiency of recent origin
Tests the whole HPA axis (gold standard)
Give insulin, measure cortisol every 30 mins for at least 2 hours

Question 17

Acute treatment for adrenal insufficiency

Answer 17

General and supportive measures (correct volume depletion/hypoglycemia)
GC replacement
Mineralocorticoid replacement (only in primary adrenal insufficiency)

Question 18

Chronic treatment for adrenal insufficiency

Answer 18

GC replacement
Mineralocorticoid replacement
Adrenal androgen replacement
Education