Exam 4 - Adrenal Disorders Flashcards
What are some clinical features of Cushing’s Syndrome?
- Amenorrhea
- Striae
- Hyperpigmentation
- Central obesity (“moon face”, “buffalo hump”)
- HTN
- Osteoporesis
- Extremity muscle wasting
What type of etiology is 70% of all Cushing’s Syndrome?
Is Cortisol high or low?
Is ACTH high or low?
Cushing’s Disease = pituitary hypersecretion of ACTH
Cortisol is high
ACTH is high
What type of etiology is 20% of Cushing’s Syndrome?
Is Cortisol high or low?
Is ACTH high or low?
Iatrogenic or Factitious Cushing’s Syndrome (ACTH-independent) - administration of excessive synthetic glucocorticoid.
Cortisol is high
ACTH is low
What is the gold standard for diagnosis of Cushing’s Syndrome?
24-hour urinary free cortisol excretion
What are the available first-line testing methods for Cushing’s Syndrome?
- 24-hour urinary free cortisol excretion
- Late-night salivary cortisol
- Low-dose dexamethasone suppression test
What is an abnormal measurement for the Low-dose dexamethasone suppression test?
What does this raise suspicion for?
Elevated cortisol of > 5 mcg/dL
High suspicion for non-suppressible cortisol production from ACTH-independent etiology (adrenal adenoma)
What is the management of Cushing’s Syndrome?
- Exogenous corticosteroids - taper to lowest therapeutic dose to control symptoms
- Pituitary adenoma - transsphenoidal resection
- Adrenal tumor - adrenalectomy
- Adrenal hyperplasia - medical therapy
What is the 1st line medical management of Cushing’s Syndrome?
What can you add if this is ineffective?
Ketoconazole
If ineffective, add Metyrapone
What are the most common etiologies of Primary Hyperaldosteronism/Conn’s Syndrome?
- Bilateral idiopathic adrenal hyperplasia (more common)
- Unilateral aldosterone-producing adenoma
What are some clinical features of Primary Hyperaldosteronism?
- Hypertension*
- Hypokalemia*
- Muscle weakness
- Paresthesias
- Headache
- Polyuria
- Polydipsia
How is Primary Hyperaldosteronism diagnosed via labs?
- Increased plasma aldosterone concentration (PAC)
- Decreased plasma renin activity (PRA) or plasma renin concentration (PRC)
- Spontaneous hypokalemia
How is Primary Hyperaldosteronism diagnosed via imaging?
CT abdomen to evaluate for adrenal adenoma or adrenal hyperplasia
What is the management for a unilateral adrenal adenoma?
Surgical removal
What is the management for bilateral idiopathic adrenal hyperplasia?
Spironolactone (1st line) - mineralocorticoid receptor antagonist
+ other antihypertensives
***Serum K+, Cr, and BP should be monitored frequently during the first 4-6 weeks of medical therapy
What disorder is due to decreased synthesis of ALL adrenocortical hormones (cortisol, aldosterone, androgens)?
Primary Adrenocortical Insufficiency: Addison’s Disease
What are clinical features associated with decreased aldosterone?
Hyperkalemia, hypotension, salt craving
What are clinical features associated with increased ACTH?
Hyperpigmentation
What disorder is due to failure of the corticotrophs to adequately secrete ACTH?
Secondary Adrenocortical Insufficiency
What disorder is due to insufficient corticotrophin-releasing hormone (CRH) from the hypothalmus?
Tertiary Adrenocortical Insufficiency
What is different regarding the clinical features of Primary Adrenocortical Insufficiency compared to Secondary/Tertiary Adrenocortical Insufficiency?
In Secondary and Tertiary Adrenocortical Insufficiency, clinical features are related to cortisol and androgen deficiency. Aldosterone is normal and hyperpigmentation does not occur.
What is the most common etiology of Primary Adrenocortical Insufficiency: Addison’s Disease?
Autoimmune destruction of the adrenal cortex
What is the most common etiology of Secondary Adrenocortical Insufficiency?
Suppression of the HPA axis through abrupt cessation of exogenous steroid
The following clinical features are associated with what disorder?
- Cortisol: Low
- Aldosterone: Low
- Androgens: Low
- ACTH: High
- CRH: High
Primary Adrenocortical Insufficiency: Addison’s Disease
The following clinical features are associated with what disorder?
- Cortisol: Low
- Aldosterone: Normal
- Androgens: Low
- ACTH: Low
- CRH: High
Secondary Adrenocortical Insufficiency
The following clinical features are associated with what disorder?
- Cortisol: Low
- Aldosterone: Normal
- Androgens: Low
- ACTH: Low
- CRH: Low
Tertiary Adrenocortical Insufficiency
The following clinical features are associated with what disorder?
- Hyperpigmentation of the skin
- Salt craving
- Postural hypotension
- Decreased pubic hair and axillary hair in females
- Weight loss
- Hypoglycemia
Primary Adrenocortical Insufficiency: Addison’s Disease
How can adrenal insufficiency be diagnosed?
- Serum AM Cortisol
- Cosyntropin (ACTH) Stimulation Test
What is the Cosyntropin (ACTH) Stimulation Test?
What constitutes an abnormal result?
Evaluates the ability of the adrenal gland to respond to ACTH
Abnormal result: Cortisol fails to increase by 7 mg/dL above baseline, OR to > 18 mcg/dL
What is the management for adrenal insufficiency?
- Short-acting glucocorticoids* (hydrocortisone BID to TID)
- Long-acting glucocorticoids (dexamethasone, prednisone if non-compliant with short-acting)
- Mineralocorticoid (fludrocortisone)
- Consider oral DHEA replacement in women
What is the classic triad associated with pheochromocytoma? What other symptom is it associated with?
Episodic headache, tachycardia, and sweating
Also associated with paroxysmal HTN
When should you suspect pheochromocytoma?
- Paroxysmal “attacks”
- Refractory HTN or onset < 20 years old
- Abdominal mass
- Family hx
- Incidentally discovered adrenal mass
What three tests are important to obtain in the initial workup for pheochromocytoma?
- Plasma metanephrines
- 24-hour urine catecholamines, metanephrines, VMA
- Clonidine Suppression Test
Once biochemical diagnosis of pheochromocytoma is made, what should the next step be and why?
CT scan of the abdomen without contrast as the majority of pheochromocytoma cases are due to a tumor of the adrenal medulla
What is the management for pheochromocytoma?
- “Chemical Sympathectomy” to stabilize patient until surgical excision
- Alpha-blocker (phenoxybenzamine) and beta blocker (propranolol)
- Surgery is definite
What is an adrenal mass lesion that is greater than 1 cm in diameter, discovered by radiologic examination?
Adrenal Incidentaloma
What is the diagnostic workup of Adrenal Incidentaloma?
- Rule out pheochromocytoma and subclinical Cushing’s Syndrome in all patients
- Rule out primary hyperaldosteronism if HTN
- Do not biopsy if known primary malignancy elsewhere or biochemical evidence of pheo
What is the management for Adrenal Incidentaloma if the workup is negative and likely benign and < 2 cm?
Repeat imaging at 6 months and repeat dexamethasone suppression test every year for 4 years
What is the management for Adrenal Incidentaloma if the workup is negative and likely benign and > 2 cm?
Consider surgical resection
What is an abnormal result in the low-dose dexamethasone suppresion test?
What disorder is an abnormal results associated with?
Cortisol ELEVATED after administration of dexamethasone 9 hours earlier.
Cushing’s Syndrome (non-suppressible cortisol production from ACTH-independent etiology)
What is an abnormal result in the Cosyntropin Stimulation test?
What disorder is an abnormal results associated with?
Cortisol DOES NOT increase after administration of ACTH.
Addison’s Disease
What is an abnormal result in the clonidine suppresion test?
What disorder is an abnormal results associated with?
Catecholamine production is NOT reduced after administration of clonidine.
Pheochromocytoma
