PATHO EXAM 3 MASTER

What is the distinguishing factor in endocrine disorders?

Where the problem originates

What do hormonal messages require to be received?

A receptor on the target cell

What is the King in the kingdom analogy of the endocrine system?

Hypothalamus

What is the Princess in the kingdom analogy of the endocrine system?

Pituitary

What is the Duke in the kingdom analogy of the endocrine system?

Gland

What is the Kingdom in the kingdom analogy of the endocrine system?

Cells of the body

What is the anterior pituitary also called?

Adenohypophysis

What type of tissue is the anterior pituitary made of?

Glandular

What are the three hormones released by the anterior pituitary?

TSH, GH, and ACTH

Does the anterior pituitary gland produce GH?

No

What is the posterior pituitary also called?

Neurohypophysis

What type of tissue is the posterior pituitary made of?

Neural

Which hormone is stored in the posterior pituitary?

ADH

Where is ADH produced?

Hypothalamus

What does the HPA axis consist of?

Hypothalamus. pituitary, adrenal

What is the neural-endocrine overlap activated as part of?

Stress response

What are common causes of hypofunction?

Congenital defects, destruction of glands, aging, receptor defects

What are common causes of hyperfunction?

Excess stimulation, excess administration of exogenous hormones

What is the cause of a primary etiology of hypothyroidism?

Glandular issue

What is the cause of a secondary etiology of hypothyroidism?

Pituitary issue

What is the cause of a tertiary etiology of hypothyroidism?

Hypothalamus issue

What controls the thyroid?

Hypothalamus & anterior pituitary

What cells do thyroid hormones affect?

Almost all cells

What type of reaction do thyroid hormones produce?

Sympathetic stimulation

Which cells produce and store T3 & T4?

Follicular cells

Which cells secrete calcitonin?

Parafollicular (C) cells

What does calcitonin do?

Regulate serum calcium

How are thyroid hormones named?

For how many iodines are on each molecule

Can any cells other than thyroid cells use iodine?

No

What is the most abundant circulating thyroid hormone?

T4

What is the most biologically active thyroid hormone?

T3

How can T3 be formed?

20% is secreted from the gland, 80% is converted from T4

What is the signaling pathway for thyroid hormone production?

Hypothalamus is stimulated to release TRH, TRH stimulates anterior pituitary to release TSH, TSH stimulates iodine uptake, and release of T3 & T4

What does the T3/T4/TSH test tell us?

Thyroid function, TSH & TRH levels differentiate etiology

What does the Thyroid antibodies test tell us?

Presence of autoimmune antibodies implicated in thyroid disorders

What does the radioactive iodine uptake test tell us?

Measure thyroid’s ability to concentrate iodine & synthesize hormones

What does a thyroid scan tell us?

Presence of nodules and their activity

Which is the rarest etiology of thyroid problems?

Tertiary

What is the cause of a primary etiology of hyperthyroidism?

Thyroid gland failure

What is the cause of a secondary etiology of hyperthyroidism?

Pituitary gland failure

What is the cause of a tertiary etiology of hyperthyroidism?

Hypothalamus failure

What is the most common cause of hypothyroidism in the United States?

Hashimoto’s

What is Hashimoto’s?

An autoimmune attack of the thyroid gland causing inflammation and gland dysfunction

What are the labs associated with primary hypothyroidism?

High TSH, low T3/T4

What are s/sx of hypothyroidism?

Weight gain, cold intolerance, constipation, low HR, brittle hair, dry skin

What is the treatment for primary hypothyroidism?

T4 replacement

What is congenital hypothyroidism called?

Cretinism

What level of etiology is cretinism?

Primary disorder

What is the pathophysiology of cretinism?

Infant born without thyroid gland or produces defective T3/T4

How is cretinism treated in the United States?

Screening at newborn stage

What causes puffy expressionless faces in hypothyroid patients?

Mucopolysaccharide accumulation

What are s/sx of cretinism?

Somnolence, poor suckling, impaired cognitive development, impaired growth, large protruding tongue, boggy non-pitting edema

What causes non-toxic goiter?

Non-cancerous non-inflammatory growth causing hyperplasia

What is the most common cause of non-toxic goiter?

Iodine defciency

What is the enlargement life in toxic goiter?

Diffuse, spread out

What is the most common cause of toxic goiter?

Overactivity, sometimes caused by nodules

What is myxedema?

Severe hypothyroidism in adults

What is the most common cause of myxedema?

Untreated or undiagnosed hypothyroidism

What are s/sx of myxedema?

Boggy non-pitting edema, scalloped tongue, bradycardia, hypothermia, severe lethargy

What are the severe outcomes of myxedema?

Coma and death

What is the treatment of myxedema?

Aggressive thyroid hormone replacement with cardiovascular support

What is the most common form of primary hyperthyroidism called?

Grave’s disease (thyrotoxicosis)

Who is Grave’s disease most common in?

Women

What causes Grave’s disease?

Autoantibodies activate TSH receptors causing continuous release of T3/T4

How common are secondary and tertiary hyperthyroidism?

Rare

What are the usual causes of secondary and tertiary hyperthyroidism?

Adenomas in the pituitary or hypothalamus

What are the labs associated with hyperthyroidism?

Low TSH, high T3/T4

What are s/sx of hyperthyroidism?

High heart rate, sudden weight loss, jitters, exopthalamus

How is Grave’s disease confirmed?

Positive autoantibody test

What is the treatment for hyperthyroidism?

Antithyroid drugs and/or removal of the thyroid gland

What is thyroid storm?

Medical emergency with an extreme manifestation of hyperthyroidism

What usually precipitates thyroid storm?

Trauma to the neck or thyroid surgery

What are the s/sx of thyroid storm caused by?

Sudden release of all thyroid hormones

What are the s/sx of thyroid storm?

High BP, high HR, high temperature

What are the severe manifestations of thyroid storm?

Coma and death

What is the treatment for thyroid storm?

Cooling blankets and beta blockers

Which hormones are produced by the outer adrenal cortex?

Mineralocorticoids

What are the actions of mineralocorticoids?

Conservation of sodium and water, elimination of potassium in kidneys,

What is the primary mineralocorticoid?

Aldosterone

What hormones are produced by the middle layer of the adrenal cortex?

Glucocorticosteroids

What are the primary actions of glucocorticosteroids?

Stimulates glucose, protein, and fat metabolism, immunosuppressant, activate inflammatory mediators

What is the main glococorticosteroid?

Cortisol

What hormones are produced by the third layer of the adrenal cortex?

Androgens

What is the main androgen?

Testosterone

Which hormones are produced by the adrenal medulla?

Epinephrine and norepinephrine

Aldosterone is largely regulated by what?

RAAS

What are you prone to under stress because of the RAAS?

Hypertension

How is the adrenal cortex controlled?

Hypothalamus detects need for steroids, releases CRF, CRF signals anterior pituitary to secrete ACTH, ACTH signals adrenal cortex to release steroids

What is Addison’s disease?

Hypocortical state

What the key feature of Addison’s disease?

Primary adrenal insufficiency

What is Cushing’s disease/syndrome?

Hypercortical state

What is the key feature of Cushing’s disease/syndrome?

S/sx due to excess cortisol

What is Conn’s syndrome?

Hyperaldosteronism

What is the key feature of Conn’s syndrome?

Affecting only the outer layer of adrenal cortex

What is the most common cause of Addison’s disease?

Autoimmune destruction of the adrenal cortex

What does Addison’s disease cause?

Deficiency of glucocorticosteroids, aldosterone, and androgens

What are the s/sx of cortisol deficiency?

Hypoglycemia, fatigue

What are the s/sx of aldosterone deficiency?

Hyponatremia, hyperkalemia, fluid loss, dehydration

What are the s/sx of androgen deficiency?

Decreased libido, amenorrhea

What causes skin hyperpigmentation in Addison’s patients?

Excess ACTH has an affinity for skin cells