Endocrinology Quiz on Hyperaldosteronism

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Questions and Answers

What is the primary cause of primary hyperaldosteronism in most cases?

Renal artery stenosis

Congestive heart failure

Adrenocortical hyperplasia

Aldosterone producing adrenocortical neoplasm (correct)

Which of the following findings is characteristic of primary hyperaldosteronism?

Increased plasma renin

Hyperkalemia

Decreased plasma renin (correct)

Normal aldosterone levels

What is the most common treatment for an adenoma causing primary hyperaldosteronism?

Medication therapy

Surgical removal (correct)

Radiation therapy

Dialysis treatment

What is the main consequence of 21-hydroxylase deficiency?

Excess production of androgens Signup and view all the answers

What characterizes primary acute adrenocortical insufficiency?

Can precipitate an adrenal crisis under stress Signup and view all the answers

Which condition is associated with secondary hyperaldosteronism?

Hypoalbuminemia Signup and view all the answers

What is the expected effect of primary hyperaldosteronism on potassium levels?

Hypokalemia Signup and view all the answers

Which condition is primarily associated with excessive aldosterone production?

Congenital adrenal hyperplasia Signup and view all the answers

What leads to adrenal hyperplasia in congenital adrenal hyperplasia?

Elevated ACTH levels due to cortisol deficiency Signup and view all the answers

What effect does adrenal hyperfunction have on potassium levels?

Increases potassium due to excessive aldosterone Signup and view all the answers

What is the most common type of functional pituitary adenoma?

Prolactinoma Signup and view all the answers

What condition is characterized by excessive water reabsorption and hyponatraemia due to inappropriate production of ADH?

Syndrome of inappropriate ADH secretion (SIADH) Signup and view all the answers

Which layer of the adrenal cortex is primarily responsible for the secretion of glucocorticoids?

Zona Fasciculata Signup and view all the answers

Which of the following is the most common cause of Cushing syndrome?

Exogenous glucocorticoids Signup and view all the answers

What is a characteristic clinical feature of Cushing syndrome?

Hyperglycaemia Signup and view all the answers

Which hormone is primarily responsible for the retention of sodium and increased blood pressure in hyperaldosteronism?

Aldosterone Signup and view all the answers

Which of the following is NOT a characteristic clinical feature of hypercortisolism?

Weight loss Signup and view all the answers

What type of diabetes results from decreased secretion of ADH, leading to polyuria and polydipsia?

Diabetes Insipidus Signup and view all the answers

Which of the following is a potential cause of endogenous Cushing syndrome?

Pituitary adenoma Signup and view all the answers

In hyperaldosteronism, which electrolyte imbalance is typically observed?

Hypokalemia Signup and view all the answers

What is the expected result of administering exogenous ACTH in a patient with primary adrenal insufficiency?

No response in cortisol levels Signup and view all the answers

Which of the following is a characteristic feature of adrenocortical neoplasms?

Can metastasize to the lungs and lymphatics Signup and view all the answers

What is the typical survival rate for patients with functioning adrenocortical adenomas?

Median survival of 2 years Signup and view all the answers

What are the main components of the adrenal medulla?

Neuroendocrine and sustentacular cells Signup and view all the answers

Which option describes the typical location of phaeochromocytomas?

May be extra-adrenal in location Signup and view all the answers

What percentage of phaeochromocytoma patients may harbor a germline mutation?

Approximately 25-30% Signup and view all the answers

What histological feature is characteristic of phaeochromocytomas?

Zellballen formation Signup and view all the answers

In which age group are adrenocortical neoplasms most commonly diagnosed?

Adults aged 30-50 Signup and view all the answers

Which condition is primarily associated with bilateral adrenal haemorrhage?

Waterhouse-Friderichsen syndrome Signup and view all the answers

What is a common cause of primary chronic adrenocortical insufficiency in 60-70% of cases?

Autoimmune adrenalitis Signup and view all the answers

Which of the following symptoms is NOT typically associated with Addison disease?

Increased appetite Signup and view all the answers

Which of these infections is most commonly linked to Waterhouse-Friderichsen syndrome?

Neisseria meningitidis Signup and view all the answers

What is the predominant cause of adrenalitis frequency increase as indicated by genetic factors?

HLA-B8 and DR-3 antigens Signup and view all the answers

In secondary adrenocortical insufficiency, which hormone remains at normal levels?

Aldosterone Signup and view all the answers

What symptoms indicate that a patient may be experiencing an acute adrenal crisis?

Severe fatigue and hypotension Signup and view all the answers

Which of the following conditions is primarily characterized by a progressive destruction of the adrenal cortex?

Addison disease Signup and view all the answers

What is the primary condition characterized by excessive hormone secretion from the endocrine glands?

Hyperfunction Signup and view all the answers

Which hormone is NOT produced by the anterior pituitary gland?

Vasopressin Signup and view all the answers

Which type of pituitary cell is responsible for producing growth hormone?

Acidophils Signup and view all the answers

What term describes the condition when receptors in the target organ are not functioning?

Pseudohypofunction Signup and view all the answers

Which pituitary tumor is most commonly encountered?

Pituitary adenoma Signup and view all the answers

Which statement best describes feedback inhibition in endocrine function?

Increased activity in the target tissue down regulates the activity of the gland Signup and view all the answers

What histological feature is associated with the anterior pituitary gland?

Mixed glandular architecture Signup and view all the answers

Which of the following is a cause of hypopituitarism?

Absence of trophic hormones Signup and view all the answers

What is a key clinical feature of hyperadrenalism?

Hyperglycemia Signup and view all the answers

Which symptom is most commonly associated with phaeochromocytoma due to catecholamine release?

Hypertension Signup and view all the answers

What is the primary purpose of administering adrenergic blocking agents during surgery for phaeochromocytoma?

To prevent adrenal crisis Signup and view all the answers

In the context of paragangliomas, what is the likelihood that they may be malignant?

10-40% Signup and view all the answers

How are elevated catecholamines typically diagnosed in patients suspected of having a phaeochromocytoma?

24 hour urinary collection Signup and view all the answers

What clinical presentation is typically observed during paroxysmal episodes of hypertension associated with phaeochromocytoma?

Episodes induced by changes in posture Signup and view all the answers

What is the expected renin level in a patient with primary hyperaldosteronism?

Decreased Signup and view all the answers

What is the most common cause of primary hyperaldosteronism?

Aldosterone producing adenoma Signup and view all the answers

During which condition is secondary hyperaldosteronism most likely to occur?

Hypoalbuminemia Signup and view all the answers

Which of the following is a typical treatment for adrenocortical hyperplasia in primary hyperaldosteronism?

Aldosterone antagonist Signup and view all the answers

Which demographic is most commonly affected by Conn syndrome?

Adults in midlife Signup and view all the answers

What is the primary outcome of 21-hydroxylase deficiency in congenital adrenal hyperplasia?

Impairment of aldosterone secretion Signup and view all the answers

In primary acute adrenocortical insufficiency, which event is most likely to precipitate an adrenal crisis?

Acute stress from surgical procedures Signup and view all the answers

Which adrenal disorder is characterized by carcinoma being more significant than adenoma?

Adrenal cortical neoplasm Signup and view all the answers

What is a potential consequence of secondary adrenocortical insufficiency?

Decreased stimulation of adrenal glands leading to adrenal insufficiency Signup and view all the answers

Hyponatremia and hyperkalemia in 21-hydroxylase deficiency can lead to which serious complication?

Cardiovascular collapse Signup and view all the answers

Which of the following correctly describes the clinical course of Waterhouse-Friderichsen syndrome?

Abrupt and devastating Signup and view all the answers

What percentage of cases of primary chronic adrenocortical insufficiency is attributed to autoimmune adrenalitis?

60-70% Signup and view all the answers

Which gastrointestinal symptoms are associated with Addison disease?

Nausea and vomiting Signup and view all the answers

Which of the following systemic conditions may co-exist in patients with Addison disease?

Hashimoto's thyroiditis Signup and view all the answers

What is a common complication of rapidly progressive hypotension due to Waterhouse-Friderichsen syndrome?

Disseminated intravascular coagulation (DIC) Signup and view all the answers

Which histocompatibility antigens are associated with an increased frequency of adrenalitis?

HLA-B8 and DR-3 Signup and view all the answers

What is the typical electrolyte imbalance seen in Addison disease due to aldosterone deficiency?

Hyperkalemia and hyponatremia Signup and view all the answers

Which condition is characterized by excessive secretion from hormone-secreting cells due to hyperplasia or neoplasia?

Endocrine hyperfunction Signup and view all the answers

What differentiates primary hypofunction from secondary hypofunction in endocrine disorders?

Congenital absence of the gland Signup and view all the answers

Which type of tumor is most commonly associated with hyperpituitarism?

Adenoma Signup and view all the answers

What structure is derived from Rathke’s pouch?

Adenohypophysis Signup and view all the answers

Which of the following correctly classifies the normal adrenal gland's histological features?

Contains cortical zones and medullary regions Signup and view all the answers

What effect does primary hypofunction typically have on upstream stimulation?

Decreased stimulation Signup and view all the answers

In terms of endocrine feedback mechanisms, what does increased activity in a target tissue lead to?

Downregulation of gland activity Signup and view all the answers

Which of the following is an example of pseudohypofunction?

Malfunction of target organ receptors Signup and view all the answers

What is a potential cause of secondary hyperfunction in the endocrine system?

Absence of feedback inhibition Signup and view all the answers

What type of cell found in the anterior pituitary is responsible for producing Prolactin?

Acidophils Signup and view all the answers

What primarily results from high cortisol levels in functioning adrenocortical neoplasms?

Atrophy of the adrenal cortex Signup and view all the answers

Which of the following characteristics is NOT associated with adrenocortical adenomas?

Always exhibit necrosis Signup and view all the answers

In which demographic group are adrenocortical neoplasms most commonly diagnosed?

Individuals aged 30-50 Signup and view all the answers

What is the approximate percentage of phaeochromocytoma patients who may harbor a germ line mutation?

25-30% Signup and view all the answers

What term describes the clusters of cells found in the histology of phaeochromocytoma?

Zellballen Signup and view all the answers

What is a common incidental finding in adrenal myelolipoma?

Fat and hematopoietic cells Signup and view all the answers

What is the most common tumor type of the adrenal medulla?

Phaeochromocytoma Signup and view all the answers

Which of the following is a characteristic symptom of phaeochromocytoma?

Surgically correctable hypertension Signup and view all the answers

Study Notes

Endocrine Pathology - Pituitary and Adrenal

The endocrine system is an integrated, widely distributed group of organs maintaining metabolic equilibrium.
Endocrine organs secrete hormones into the bloodstream to regulate organ activity.
Pure endocrine organs include the pituitary, thyroid, parathyroid, and adrenal cortex/medulla.
Endocrine components are found in mixed organs – pancreas, ovaries, and testes.
Endocrine glands are regulated by complex mechanisms with stimulatory and inhibitory signals.
The adrenal glands are located above each kidney, weighing approximately 4 grams each.
The pituitary gland, or hypophysis, is located in the sella turcica, weighing 500mg and measuring 10-15mm in size.
The pituitary consists of both an anterior, adenohypophysis, and posterior lobe, neurohypophysis, derived from Rathke's pouch and the 3rd ventricle, respectively.
Multiple separate histological cell types exist in the anterior pituitary

Learning Outcomes

Describe feedback loops in endocrine organs
Identify histological features of the normal pituitary gland
List causes of hyper and hypopituitarism
Classify pituitary tumors
Identify histological features of the normal adrenal gland
Describe clinical features and presentation of hypo- and hyperadrenalism
Outline and illustrate pathological features of adrenocortical and medullary lesions
Classify adrenal tumors

Overview - Endocrine System

The endocrine system is a group of organs that control metabolic balance between various organs.
These organs secrete chemical messengers, hormones, into the bloodstream to regulate the activity of an organ.

Endocrine System (Types)

Pure endocrine organs: pituitary, thyroid, parathyroid, adrenal (cortex & medulla).
Endocrine components in mixed organs: pancreas, ovary, testis

Endocrine System (Feedback)

Endocrine glands are under complex regulatory control with stimulatory and inhibitory signals.
Trophic releasing hormones
Trophic hormones
- Increased activity in the target tissue downregulates the gland secreting the stimulating hormone.
Release inhibiting hormones.

Feedback Regulation in the Endocrine System

The hypothalamus (brain) regulates the pituitary gland.
Hypothalamic factors (releasing and inhibiting) stimulate/inhibit the pituitary.
Circulating hormones (from the pituitary) influence target tissues/organs.
Feedback loops (positive and negative) maintain hormone levels.

Feedback Regulation of Thyroid Hormone

TRH (thyrotropin-releasing hormone) from hypothalamus stimulates TSH (thyroid-stimulating hormone) release from the pituitary.
TSH stimulates the thyroid to produce T4 and T3 (thyroid hormones).
Increased levels of T4 and T3 inhibit TRH and TSH release, creating a negative feedback loop.

Feedback Regulation of Cortisol

Stress triggers CRH (corticotropin-releasing hormone) from hypothalamus, activating ACTH (adrenocorticotropic hormone) in the pituitary
ACTH stimulates the adrenal gland to produce cortisol
Elevated cortisol inhibits CRH and ACTH release, creating a negative feedback loop

Endocrine Function

Upstream stimulation triggers hormone secretion in the endocrine organ.
The hormone acts upon an end-organ.

Disease in Endocrine Organs

Typically recognized through hyperfunction (excessive hormone secretion), hypofunction (decreased hormone secretion), or enlargement/mass effect.

Endocrine Hyperfunction

Excessive hormone secretion can result from
- Hyperplasia or neoplasia of hormone-secreting cells
- Increased stimulation/decreased feedback inhibition
- Ectopic hormone production

Endocrine Hypofunction

Decreased hormone secretion from
- Primary hypofunction (congenital absence, hypoplasia, destruction of the gland)
- Secondary hypofunction (absence of trophic hormones)
- Pseudohypo function (target organ receptors not functioning)

Pituitary Gland

500mg weight, 10-15mm size
Two functionally separate components: anterior (adenohypophysis) and posterior (neurohypophysis) lobes
Anterior lobe (adenohypophysis): derived from Rathke's pouch
Posterior lobe (neurohypophysis): derived from the 3rd ventricle

Pituitary Gland (Anatomy)

Pituitary (hypophysis) is comprised of:
- Paraventricular nucleus
- Supraoptic nucleus
- Infundibulum
- Pars tuberalis
- Pars nervosa
- Pars distalis
- Pars intermedia

Anterior Pituitary (Cell Types)

Acidophils
Chromophobes
Basophils

Anterior Pituitary Hormones

Growth Hormone (GH)
Prolactin (PL)
Thyroid Stimulating Hormone (TSH)
Follicle Stimulating Hormone (FSH)
Luteinizing Hormone (LH)
Adrenocorticotrophic Hormone (ACTH)
Melanocyte Stimulating Hormone (MSH)

Control of Anterior Pituitary

Mostly controlled by hypothalamic positive stimulus except for Prolactin and Growth Hormone (partly)

Hyperpituitarism

The most common pathology is a functioning adenoma
Carcinoma is rare
Adenomas often show no metastasis

Pituitary Adenomas

10% of primary intracranial neoplasms
Commonly occur between ages 40-60
Typically an isolated disorder, not part of MEN1

Pituitary Adenomas (Types)

Functional adenomas: prolactinomas (50%), somatotropinomas (15%), adrenocorticotropinomas, gonadotropinomas (4%), thyrotropinomas(<1%)
Non-functional adenomas (null-cell): 20%

Pituitary Adenomas (Symptoms)

Hormone overproduction (prolactin, GH, ACTH, TSH, FSH/LH)
Space-occupying effects (optical chiasm pressure, increased intracranial pressure, hormone deficiencies)

Prolactinoma

Elevated prolactin levels
Can manifest subtly with low libido, impotence in males, and amenorrhea, sterility & galactorrhea in females
Local pressure effects can occur

How Can Prolactin Be Increased?

Prolactinoma
Pregnancy/Lactation
Stalk compression

Growth Hormone (Somatotropic) Adenomas

Often bihormonal (+PRL)
Pre-pubertal: giantism
Post-pubertal: acromegaly

Acromegaly (Symptoms)

Appearance changes (prognathism, brow protrusion, broad nose/hands/feet, enlarged tongue)
Other symptoms (carpal tunnel syndrome, glycosuria/diabetes, joint pain, deafness).

Other Adenomas

ACTH-producing adenomas (usually microadenomas, silent Cushing's disease)
Gonadotroph pituitary adenomas.
Thyrotrophic adenomas (rare)
Null-cell adenomas

Cushing's Disease

Hypercortisolism due to excess ACTH from the pituitary.

Hypothalamic-Pituitary Diseases

Primary hypothalamic-pituitary diseases
Pituitary disease (70-80% of cases)
Pituitary adenoma [Cushing's disease]
Adrenal causes
Adenoma, carcinoma, nodular hyperplasia
Paraneoplastic cause
Secretion of ectopic ACTH by a neoplasm

Hypothyroidism

Decreased secretion of ADH leads to polyuria and polydipsia
Primarily due to head injury/surgical trauma, neoplasia, or inflammation
Differentiate to nephrogenic diabetes insipidus.

SIADH

Syndrome of inappropriate antidiuretic hormone secretion (SIADH)
Excess ADH leads to excessive water reabsorption, resulting in water overload and hyponatremia.

Adrenal Cortex

Structures: zona glomerulosa, zona fasciculata, zona reticularis
Hormones: glucocorticoids (zona fasciculata and zona reticularis), mineralocorticoids (zona glomerulosa), androgens (zona reticularis)

Adrenocortical Hyperfunction

Primary hyperaldosteronism: caused by aldosterone-producing adrenocortical neoplasms (Conn syndrome), adrenal cortical hyperplasia.
Secondary hyperaldosteronism: Overproduction of aldosterone from activation of renin-angiotensin system.
Adrenogenital syndrome: disorders of sexual differentiation (including congenital adrenal hyperplasia).

Adrenocortical Hyperfunction (Cushing Syndrome, causes)

Hypercortisolism (elevated glucocorticoid levels), exogenous (iatrogenic administration of glucocorticoids) or endogenous (pituitary or adrenal disease; paraneoplastic causes).

Adrenocortical Hyperfunction (Clinical Features)

Hypertension, weight gain (truncal obesity), buffalo hump, moon face; reduced muscle mass, hyperglycemia, glucosuria, polydipsia, fragile skin, striae.
Susceptibility to infections, mental disturbances, hirsutism, and menstrual abnormalities.

Hyperaldosteronism

Aldosterone acts on renal tubules and collecting ducts to retain sodium, increase water retention, and increase blood pressure.
Primary hyperaldosteronism is overproduction of aldosterone (suppresses renin-angiotensin system) -> hypertension and hypokalemia.
Diagnosis involves elevated aldosterone and reduced plasma renin.
Common causes include adrenal adenoma (Conn syndrome), adrenal cortical hyperplasia.

Secondary Hyperaldosteronism

Overproduction of aldosterone due to activation of the renin-angiotensin system.
Occurs with heart failure, decreased renal perfusion (renal artery stenosis), hypoalbuminemia, and pregnancy.
Treatment: correction of the underlying cause.

Adrenogenital Syndromes

Disorders of sexual differentiation, primary gonadal or primary adrenal disorders.
Two compounds secreted by the adrenal cortex (dehydroepiandrosterone and androstenedione). These are converted to testosterone in peripheral tissues

Adrenogenital Syndromes (Causes)

Androgen adrenocortical neoplasm (carcinoma > adenoma)
Congenital adrenal hyperplasia (group of autosomal recessive deficiency disorders resulting in increased androgen production leading to virilisation, deficiency in cortisol, high ACTH, adrenal hyperplasia).

Adrenogenital Syndromes (21-Hydroxylase Deficiency)

Common cause of congenital adrenal hyperplasia (90% of cases)
Results in insufficient mineralocorticoids and glucocorticoids and excess androgens → hyponatremia, hyperkalemia, acidosis, hypotension.

Adrenal Hypofunction

Primary adrenocortical insufficiency (Addison's disease): primary adrenal disease
- Primary acute : serious medical emergency due to stressors (infections, trauma, surgical procedures.
- Primary chronic: autoimmune adrenalitis (60-70% of cases), infections, particularly TB, or metastatic carcinomas.

Adrenal Hypofunction (Clinical Manifestations)

Progressive weakness, fatigue, GI symptoms (anorexia, N&V, weight loss), hyperpigmentation, hyperkalemia, hyponatremia, hypotension, hypoglycemia.
Stress triggers acute adrenal crisis

Secondary Adrenocortical Insufficiency

Decreased ACTH stimulation leading to reduced cortisol and androgen (but aldosterone is normal)

Adrenocortical Neoplasms

Adenomas/Carcinomas
Typically age 30-50, functional adenomas could be responsible for various hyperadrenalisms.
High cortisol suppresses ACTH ->atrophy in adjacent cortex and contralateral glands
Adenomas are mostly clinically silent but can be responsible for overproduction of hormones.
Adrenocortical carcinomas are rare, usually over 20cm, poorly demarcated with necrosis, hemorrhage and cystic changes.

Adrenal Myelolipoma

Benign tumor of the adrenal gland.
Contains fat and hematopoietic cells.

Adrenal Medulla

Composed of neuroendocrine chromaffin cells and sustentacular cells.
Responds to the sympathetic nervous system by secreting catecholamines.

Adrenal Medulla Diseases

Phaeochromocytoma: neoplasm of chromaffin cells (often, but not always, presenting with hypertension)
Neuroblastomas / ganglion cell tumours: neuronal neoplasms common in childhood.

Phaeochromocytoma

Uncommon neoplasm (0.1%-0.3% of hypertensive pts)
10%: extra-adrenal paraganglia
10%: bilateral (~50% of familial cases)
10%: malignant (adrenal vs. 20-40% extra-adrenal)
~25-30% of pts with a germline mutation in the succinate dehydrogenase complex (SDHB, SDHC, SDHD)
"Rule of 10s"

Phaeochromocytoma (Clinical Features)

Hypertension, tachycardia, palpitations, headaches, sweating, tremor, abdominal/chest pain, Paroxysmal hypertension episodes (exercise, stress, posture change).
Catecholamine cardiomyopathy

Phaeochromocytoma (Diagnosis)

24-hour urinary collection of catecholamines and metabolites (e.g., VMA, metanephrines)

Extra-Adrenal Paraganglia Tumours

Carotid body tumors, chemodectomas
10-40% malignant
10% metastasize widely
15-25% multicentric

Pituitary and Adrenal Pathologies: Learning Outcomes

Describe feedback loops in endocrine organs
Histological features of normal pituitary/adrenal glands
Causes of hyper/hypo-pituitarism
Pituitary tumor classification
Clinical features of hypo/hyper-adrenalism
Adrenal tumor classification.

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Test your knowledge on primary and secondary hyperaldosteronism with this quiz. Explore symptoms, causes, and treatments related to adrenal gland disorders. Ideal for students of endocrinology or anyone interested in hormone regulation.