Adrenal Gland Disorders I Flashcards
What are the histological components of the adrenal gland?
Capsule, Cortex (glomerulosa, fasciculata, reticularis), Medulla.
What is the primary biosynthetic precursor for corticosteroids in the adrenal cortex?
Cholesterol.
List the hormones produced in the adrenal cortex.
- Cortisol
- Aldosterone
- DHEA
- Testosterone
- Androstenedione
- Dihydrotestosterone.
What regulates cortisol and androgen production?
Hormones produced by the hypothalamus and anterior pituitary gland.
What major system regulates aldosterone production?
Renin-angiotensin system.
What triggers the activation of the renin-angiotensin system?
Decreased blood pressure.
How do corticosteroids affect gene transcription?
They bind intracellular receptors, and the receptor/ligand complex binds DNA to affect transcription.
What are the six classes of steroid receptors?
- Glucocorticoid
- Mineralocorticoid
- Progestin
- Oestrogen
- Androgen
- Vitamin D.
What are the major actions of cortisol?
- CNS: Mood lability, euphoria/psychosis, decreased libido
- Circulatory/Renal: Cardiac output, blood pressure regulation
- Immunological: Decreased capillary permeability, decreased leukocyte migration
- Metabolic: Increased blood sugar, lipolysis, proteolysis
- Bone/Connective Tissue: Accelerates osteoporosis.
What are the three main clinical applications of corticosteroids?
- Suppress inflammation
- Suppress immune system
- Replacement treatment.
What does aldosterone primarily regulate?
Extracellular volume and blood pressure.
What are the clinical features of Addison’s disease?
- Anorexia
- Weight loss
- Fatigue
- Dizziness
- Abdominal pain
- Skin pigmentation.
What is the commonest cause of primary adrenal insufficiency?
Autoimmune destruction of adrenal cortex.
What are the laboratory findings indicative of adrenal insufficiency?
- Decreased sodium
- Increased potassium
- Hypoglycemia.
What is the treatment for adrenal insufficiency?
Hydrocortisone as cortisol replacement and fludrocortisone as aldosterone replacement.
What is an adrenal crisis?
A life-threatening emergency requiring immediate treatment.
True or False: Skin pigmentation is increased in secondary adrenal insufficiency.
False.
What are the clinical features of Cushing’s syndrome?
- Easy bruising
- Facial plethora
- Striae
- Proximal myopathy.
What is the most common cause of endogenous Cushing’s syndrome?
Adrenal adenoma.
What tests are used to diagnose Cushing’s syndrome?
- Overnight dexamethasone suppression test
- 24-hour urinary free cortisol
- Late night salivary cortisol.
What is the commonest cause of iatrogenic Cushing’s syndrome?
Prolonged high-dose steroid therapy.
What are the endocrine causes of hypertension?
- Primary Aldosteronism
- Cushing’s syndrome
- Renal disease.
What characterizes primary aldosteronism?
Autonomous production of aldosterone independent of its regulators.
What is the management for primary aldosteronism due to adrenal adenoma?
Unilateral laparoscopic adrenalectomy.
Fill in the blank: Cortisol/androgen secretion is regulated by _______.
pituitary ACTH secretion by a negative feedback mechanism.
What is the outcome of adrenal disorders related to excess cortisol?
High mortality and various clinical features such as hypertension and osteoporosis.
What should patients with adrenal insufficiency carry for emergencies?
Emergency Steroid Card.
What is the outcome of case 3 after left adrenalectomy?
BP 124/78mmHg, plasma potassium normal
This indicates successful management of adrenal-related issues.
What are the major sources of human glucocorticoids, mineralocorticoids, and androgens?
Adrenal cortex
The adrenal cortex is crucial for the production of these hormones.
How is cortisol and androgen secretion regulated?
By pituitary ACTH secretion through a negative feedback mechanism
This mechanism helps maintain hormonal balance.
What controls aldosterone secretion?
Renin-angiotensin system and plasma K+ levels
These factors are essential for regulating blood pressure and fluid balance.
What are the physiological effects of cortisol?
Cortisol plays a vital role in the body’s response to stress
Multiple effects including metabolism regulation and stress response
.
What is the role of aldosterone?
Regulates blood pressure and electrolyte excretion
Aldosterone is key in maintaining fluid balance and blood pressure.
What is the consequence of adrenal insufficiency?
Fatal and requires lifelong replacement of cortisol and aldosterone
Patients must be carefully managed to avoid life-threatening complications.
What can cause cortisol excess?
Iatrogenic causes, disorders of the pituitary (ACTH-dependent), or adrenal gland (non-ACTH dependent)
Understanding the source is crucial for effective treatment.
What are common causes of aldosterone excess?
Bilateral adrenal hyperplasia or adrenal adenoma
These conditions can lead to hypertension and require different treatment approaches.
How is bilateral adrenal hyperplasia treated?
Treatment often involves medications to manage hormone levels.
How is adrenal adenoma treated?
Surgical intervention is often necessary to remove the adenoma
