Bolick ch 24 Endocrine

Question 1

where is the hypothalamus located

Answer 1

base of the brain stem

Question 2

how is the hypothalamus linked to the pituitary gland

Answer 2

via the pituitary gland

Question 3

what two systems are involved in the hypothalamus

Answer 3

neuroendocrine organ

Question 4

what does the hypothalamus regulate

Answer 4

hormone secretion from the pituitary gland by secretion of specific stimulating and inhibiting hormones

Question 5

hypothalamic hormones are also referred to as

Answer 5

factors

Question 6

what are the hypothalamic hormones that are also referred to as factors

Answer 6

GHRH (GH releasing hormone)

SRIF (GH inhibiting hormone or somatostatin)

PIH (prolactin inhibiting hormone or dopamine)

TRF (thyrotropin releasing hormone)

CRF (corticotropin releasing hormone)

GnRH (gonadotropin releasing hormone)

Question 7

How does the pituitary gland respond to the hypothalamic hormones

Answer 7

by releasing trophic hormones that effect target glands - these glands produce hormones that feed back to the hypothalamus and pituitary gland to regulate the trophic hormone production

Question 8

what does the anterior pituitary gland regulate

Answer 8

physiological processes including

stress
reproduction
lactation
growth

Question 9

adenohypophysis

Answer 9

anterior pituitary gland

Question 10

what does Anterior pituitary gland secrete

Answer 10

Adrenocorticotropic hormone (ACTH)

Luteinizing hormone (LH)

follicle stimulating hormone (FSH)

GH
PRL

thyroid stimulating hormone (TSH)

Question 11

what secretes aldosterone

Answer 11

adrenal gland - glomerulosa

Question 12

what does aldosterone do

Answer 12

it is a mineralocorticoid

regulates sodium and water balance

Question 13

what secretes cortisol

Answer 13

adrenal gland - fasciculata

Question 14

what does cortisol do

Answer 14

regulates the level of carbohydrate

Question 15

what secretes progesterone, estrogen, and androgens?

Answer 15

adrenal gland - reticularis

Question 16

glucocorticoids are responsible for regulating what?

How does it do this?

Answer 16

the body’s response to stress primarily by increasing gluconeogenesis, increasing cardiac output and suppressing immune function

Question 17

Mineralocorticoids control what and how?

Answer 17

intravascular volume and maintain hemodynamic stability by regulating sodium and water balance

Question 18

what catecholamines are accountable for the “flight or fight” response when the body receives a threat

Answer 18

epinephrine and norepinephrine

Question 19

when the body senses that the level of cortisol is low what is that tied to?

Answer 19

Stress - means the body is stressed

Question 20

what happens when the level of cortisol is low?

Answer 20

activation of the hypothalamic-pituitary-adrenal axis (HPA axis)

a message is sent to the hypothalamus -> release corticotrophin releasing hormone (CRH) ->Anterior pituitary gland -> release adrenocorticotrophic hormone (ACTH) -> adrenal cortex releases cortisol

Question 21

Okay so your cortisol is low, your body activated the HPA axis…..now, cortisol is no longer needed. what happens next

Answer 21

cortisol travels to the hypothalamus and anterior pituitary -> inhibits further release

Question 22

the secretion of aldosterone is controlled primarily by

Answer 22

renin-angiotensin system and circulating potassium levels

Question 23

In response to low circulating volume, what happens in the kidney

Answer 23

Kidney releases renin-> converted to angiotensinogen in the liver forming angiotensin I -> Angiotensin converting enzyme (ACE) in the lungs converts angiotensin I to angiotensin II ->goes to adrenal cortex -> releases aldosterone ->kidney reabsorbs sodium and water -> blood volume increases

Question 24

adrenal dysfunction can be categorized into what 4 groups

Answer 24

Primary AI (adrenal insufficiency)

Secondary AI

Tertiary AI

relative AI

Question 25

Primary AI is the result of can be from what

Answer 25

from a destroyed or inactive adrenal gland or a hormone production failure ``` Addison disease Adrenal hemorrhage (seen in water-house-Friderichsen syndrome Severe sepsis metastatic infiltration surgical removal granulomatous lesions (TB) ```

Question 26

non-traumatic causes of adrenal hemorrhage

Answer 26

ACTH adrenal vein spasm thrombosis normally limited venous drainage of the adrenal in the pathogenesis of this condition the adrenal gland has a rich arterial supply and a limited venous drainage that is critically dependent on a single vein. during stress, ACTH secretion increases ->stimulates adrenal arterial blood flow that may exceed the venous drainage capacity and could lead to hemorrhage

Question 27

adrenal vein thrombosis can occur in adrenal hemorrhage and in association with

Answer 27

sepsis heparin-induced thrombocytopenia primary antiphospholipid antibody syndrome disseminated intravascular coagulation (DIC)

Question 28

bilat adrenal hemorrhage commonly leads to

Answer 28

acute AI and adrenal crisis

Question 29

what is the most common infection associated with AI

Answer 29

meningococcemia

Question 30

Primary AI that is a result of hormone production failure is associated with

Answer 30

CAH (congenital adrenal hyperplasia) | failure to produce corticosteroids

Question 31

in infancy what is the most common cause of AI

Answer 31

CAH (congenital adrenal hyperplasia)

Question 32

Secondary AI is associated with the deficiency of

Answer 32

ACTH (adrenocorticotrophic hormone) remember ACTH travels to the adrenal cortex telling it to release cortisol. (when the body is stressed)

Question 33

what are most common causes of ACTH (adrenocorticotrophic hormone) deficiency

Answer 33

hypopituitarism secondary to primary pituitary disease congenital pituitary lesions developmental anomalies such as anencephaly, holoprosencephaly and craniopharyngiomas

Question 34

what is the most common reason for ACTH (adrenocorticotrophic hormone) deficiency in childhood

Answer 34

Craniopharyngiomas

Question 35

which AI is defined as a hypothalamic decrease in CRH (corticotrophin-releasing hormone) secretion or production

Answer 35

Tertiary AI

Question 36

most common cause of Tertiary AI (adrenal insufficiency) what populations are at risk

Answer 36

suppression of the HPA axis from prolonged use of glucocorticoids usually from rapid steroid taper or abrupt steroid withdrawal think of those using glucocorticoids to manage their disease ``` asthma history of organ transplant leukemia neurosurgical (pre- and post op) nephrotic syndrome other kidney diseases collagen vascular diseases such as lupus erythematosus and RA ``` may take HPA axis until more than 1 month after therapy is stopped

Question 37

In the event that a pt undergoes additional stressors such as a surgical procedure or severe infections, they are assumed to be adrenal deficient for how long after stopping therapy unless what?

Answer 37

1 year after | unless a normal ACTH stimulation test is documented

Question 38

what is relative AI

Answer 38

every critical ill pt has some degree of relative AI used when there are high absolute cortisol levels present but they are relatively insufficient to overcome the degree of physiologic stress on the patient

Question 39

critically ill children with catecholamine-resistant shock commonly show

Answer 39

absolute and relative AI

Question 40

AI is absent in children with ------- shock

Answer 40

fluid-responsive shock

Question 41

neonate and HPA axis

Answer 41

immature- can further limit the infants ability to increase cortisol production in response to stress which leads to neonatal AI

Question 42

How do we screen for congenital adrenal hyperplasia (CAH)

Answer 42

genetic newborn screening

Question 43

when does CAH usually present

Answer 43

first few weeks of life

Question 44

what deficiency is associated with CAH

Answer 44

21- hydroxylase deficiency (21-OHD)

Question 45

Males with CAH usually present in a

Answer 45

salt-wasting crisis at 1-2 weeks of age accounts for 95% of all cases

Question 46

what happens in CAH

Answer 46

the missing enzyme (21-HD) reduces the production of cortisol and aldosterone by the adrenal glands -> AI The pituitary perceives there is not enough cortisol so more cholesterol is delivered. Because there is still reduced production of cortisol and aldosterone, the extra cholesterol is converted into androgen the excess androgen leads to ambiguous genitalia which makes CAH easier to recognize in female infants

Question 47

Positive TSI antibody test is associated with

Answer 47

Graves

Question 48

subacute thyroiditis is associated with a _____ ESR

Answer 48

high

Question 49

presence of TPO is associated with

Answer 49

Hashiomoto's disease