L12 - Adrenal Diseases

Question 1

Adrenal Glands?

Answer 1

Adrenal Cortex Layers / Steroid Hormones

Zona Glomerulosa: Mineralocorticoids (Aldosterone)
ZonaFasciculata: Glucocorticoids (Cortisol)
ZonaReticularis: Gonadocorticoids (Androgens)

Question 2

Adrenal Disorders?

Answer 2

Hyperadrenalism
• Aldosterone: Conn’s syndrome
• Cortisol: Cushing’s syndrome

Hypoadrenalism
• Addison’s disease
• Congenital Adrenal Hyperplasia

Question 3

Hypothalamic-Pituitary-Adrenal Axis?

Answer 3

Hypothalamus:
• Corticotrophin-releasing hormone (CRH)

Pituitary:
• pro-opiomelanocortin (POMC)
- Adrenocorticotrophic hormone (ACTH)

Question 4

Steroid Hormones Biosynthesis?

Answer 4

**Check slide 7/40

Question 5

Mineralocorticoid: Aldosterone function and regulation?

Answer 5

**Check slide 8-10/40

Question 6

Hyperaldosteronism-excessive aldosterone: Primary and secondary?

Answer 6

Primary hyperaldosteronism “Conn’s syndrome”
• Adrenal Adenoma
• Lab finding: High aldosterone, low renin

Secondary hyperaldosteronism (high renin) 
• Common, associate with renal, heart or liver disease 
• Lab finding: High aldosterone, high renin

Question 7

Glucocorticoid: Cortisol and actions?

Answer 7

**Check slide 17-18/40

Question 8

Hypercortisolism-Excessive Cortisol

Answer 8

Question 9

Hypercortisolism = Cushing’s syndrome?

Answer 9

Primary hypercortisolism
• Adrenal tumor

Secondary hypercortisolism
• Pituitary tumors–referred to ‘Cushing’s disease’
• “Ectopic” ACTH production by non-pituitary tumors

Iatrogenic (drug) or exogenous: steroid medication

Question 10

Cushing’s syndrome etiologies?

Answer 10

**Check slide 21/40

Question 11

Laboratory Investigations of Cushing’s Syndrome?

Question 12

Diagnosis of Cushing’s Syndrome?

Answer 12

Confirmation Test (Dynamic test)
• Dexamethasone suppression tests
• Dexamethasone is an exogenous corticosteroid
• Acts like cortisol
• 2 versions with different utility
• Low dose –confirm Cushing Syndrome diagnosis
- Give drug at midnight, measure cortisol at 8 am the following day
- All etiologies of Cushing’s Syndrome will yield elevated cortisol regardless at this low dose
• High dose –determine etiology
- Give drug at midnight, measure cortisol and ACTH at 8 am the following day
- Dose is potent enough to inhibit pituitary adenoma ACTH

**Check slide 23/40 for Interpretation

Question 13

Adrenal Disorders: Other names for Hypoadrenalism?

Answer 13

also called Addison’s disease or Adrenal Insufficiency

Addison’s –Adrenal’s down (versus Cushing’s –Cortisol Up)

Question 14

Hypoadrenalism: Primary and Secondary?

Answer 14

Primary hypoadrenalism
• Autoimmune disease
• Metastatic destruction
• Haemorrhage
• Genetic disease: inherited enzyme deficiency in steroidogenesis

Secondary hypoadrenalism
• ACTH deficiency: hypopituitarism

Question 15

Clinical and Biochemical Features?

Answer 15

• Aldosterone (decease)

Hyponatremia
Hyperkalemia
Blood Pressure/Volume (decease)
Dehydration

• Cortisol (decease)

Hypoglycemia
Mental Depression
Muscle weakness

• Androgen (decease)

Lack of axillary and pubic hair
Small Testicles

Question 16

Acute adrenal crisis (Addisonian crisis)?

Answer 16

Shock (hypotension, tachycardia, and oliguria)
Seizures, coma, and death if untreated

Question 17

Adrenal Insufficiency: Clinical Features?

Answer 17

Excess ACTH
• Increased pigmentation particular: hands & mouth

Question 18

Congenital Adrenal Hyperplasia (CAH)?

Answer 18

a group of inherited metabolic disorders of adrenal steroid hormone biosynthesis

**Check slide 35/40

Question 19

Adrenal Insufficiency: Dynamic Test?

Answer 19

ACTH stimulation test:
• I.V. Synacthen stimulation (1-24 ACTH analogue test)
• Measure baseline plasma/serum cortisol, 60min,120min

**Check slide 38/40 for Interpretation