Disorders of Endocrine System Flashcards
Posterior pituitary gland (neurohypophysis) hormones
ADH (vasopressin and antidiuretic hormone) and Oxytocin
pituitary gland hormones are triggered by what gland?
the hypothalamus
Thyroid gland location
anterior part of neck
thyroid gland function and which hormones do they produce?
controls rate of body metabolism and growth, produces T4 and T3 and thyrocalcitonin (calcitonin)
what does the thyroid gland require to work?
iodine
which cells specifically in they thyroid gland produce calcitonin?
parafollicular cells
enterohepatic circulation
reabsorption of the thyroid hormones from bile back into liver
Tertiary level and hormone that is secreted
Hypothalamus which secretes TRH (thyrotropin releasing hormone)
Secondary level and hormone that is secreted
Anterior pituitary which secretes TSH (Thyroid stimulating hormone)
primary level and hormone that is secreted
thyroid which secretes T3 and T4
and increase in ATP does what to thyroid hormones?
increases it
Somatostatin dopamine is secreted by which gland and what does it do?
Hypothalamus, it inhibits the TRH and TSH secretion
How does the thyroid hormone affect the heart tissue?
it increases HR by increasing affinity of B-adrenergic receptors
How do the thyroid hormones affect adipose tissue?
it stimulates fat breakdown
How do the thyroid hormones affect muscle tissue?
it increases protein breakdown
How do the thyroid hormones affect bone?
promotes normal growth and accelerates bone turnover
How does the thyroid hormone affect the nervous system?
promotes brain development
How does the thyroid hormone affect the gut?
it increases rate of carbohydrates absorption
How does the thyroid hormone affect lipoproteins?
it stimulates formation of LDL receptors
Thyroid hormones need to bind to what?
proteins
what disease inhibits the binding of proteins and thyroid hormone together?
liver disease
which hormones are metabolically active, free t4 and T3 or protein bound T4 and T3?
free
the HPT axis regulation of thyroid is regulated by bound or unbound T3 and T4?
unbound –free
Radioactive Iodine Uptake (RAI)
measures the absorption of iodine isotope to determine how the thyroid gland is functioning,
normal 5-35% in 24 hrs
Radioactive Iodine Uptake (RAI) elevated test levels indicate?
hyperthyroidism, thyrotoxicosis, increased iodine excretion or decreased iodine absorption
Radioactive Iodine Uptake (RAI) decreased test levels indicate?
a low T4, use of antithyroid meds, thyroiditis, myexdema or hypothyroidism
which thyroid hormone decreases with again?
T3
T3 and T4 Resin uptake test
blood tests for the diagnosis of thyroid disorders
Thyroid Stimulating Hormone (TSH) Test
blood test used to monitor therapy and to diagnosis primary hypothyroidism
Thyroid scan process
iodine containing meds and thyroid meds are held for 2 weeks, iodine is ingested and scan is done to see hot and cold spots
needle aspiration of thyroid tissue
used for cytological exam, light pressure afterward
low or high thyroid causes goiters? and how long before you see it?
both, hyper- goiter is there initially, hypo- goiter comes later
Goitrogens
substances that block thyroid hormone synthesis and make huge goiters
Rutabagas, cabbage, turnips, cassava
Foods that are goitrogens
PTU, MTZ, nitroprusside, Lithium, sulfonylureas are medications that can cause?
Goiters because they block thyroid hormone synthesis
Graves Disease
hyperthyroidism, antibody binds to TSH receptors to produce more T3/T4, gland is symmetrically enlarged
Exopthalmos and when does it occur?
protrusion of eyeball, hyperthyroidism
Proptosis and when does it occur?
forward displacement and entrapment of eye, hyperthyroidism
Thyroid Storm
condition that occurs during manipulation of thyroid gland that releases thyroid hormones into blood stream, can occur from severe infection and stress
Thyroid Storm s/s
fever, increased HR, tremors, CHF, pulm edema
what do you want to do before surgery to prevent thyroid storm?
give treatment to bring down thyroid production
Hashimotos Thyroiditis
destruction of thyroid follicles and lymphocytic infiltration with lymphoid follicles
Cretinism and s/s
severe thyroid hypofunction in fetus, yellow skin, large tongue, dry skin
myxedema
diffue non-pitting puffiness of skin d/t accumulation of muco-polysaccharides (b/c of hypothyroidism)
myxedema coma
rare, results in persistent low thyroid production can be cause by acute illness, rapid withdrawl of thyroid meds
initial s/s of hyperthyroidism
goiter, nervousness, palpatasions, diarrhea
later s/s of hyperthyroidism
tremor, muscle weakness, dyspnea, confusion, dependent edema
incidental s/s hyperthyroidism
heat intolerance, diaphoresis, increased appetite
initial s/s of hypothyroidism
depression, cold intolerance, meorrhagia
later s/s of hypothyroidism
goiter, weight gain, myxedema, memory loss
incidental s/s hypothyroidism
bradycardia, impotence, habitual abortion
sub-clinical hypothyroidism
elevated TSH but normal circulating T3/T4
sub-clinical hyperthyroidism
low TSH but normal circulating T3/T4
what are the elderly at risk for with sub-clinical hyperthyroidism?
afib
what are the elderly at risk for with sub-clinical hypothyroidism?
atherosclerosis and MI
parathyroid gland
controls calcium and phosphorus metabolism, produces parathyroid hormone (PTH)
calcium is bound to?
albumin and globulins
If blood is alkalotic what happens to calcium levels?
calcium goes on to plasma proteins and becomes inactive which leads to s/s of hypocalcemia
if blood is acidotic what happens to calcium levels?
calcium will come off plasma proteins and become active which leads to s/s of hypercalcemia
if there are high phosphate levels what happens to calcium and PTH?
calcium levels are lowered which stimulates PTH
parathyroid hormone related peptide
secreted by tumor cells, responsible for hypercalcemia of malignancy
primary hyperparathyroidism
excessive autonomous production of PTH caused by cancers
secondary hyperparathyroidism
diffuse glandular hyperplasia resulting from a defect outside the parathyroids cause by severe calcium and vit D deficiency and chronic renal failure
s/s hyperparathyroidism
s/s of HIGH CALCIUM, nephrocalcinosis (calcium stones), metabolic acidosis, polyuria, weakness, depression, bone pain
hypoparathyroidism
complication of thyroid or parathyroid surgery, autoimmune
s/s hypoparathyroidism
s/s of LOW CALCIUM, trousseau’s sign, chyostek’s sign, increased neuromuscular irritability!
adrenal gland
regulates sodium and electrolyte balance through aldosterone
adrenal cortex location
outer shell of adrenal gland
adrenal cortex function
makes cortisol, aldostrone, secretes sex hormones
adrenal medulla location
inner core of adrenal gland
adrenal medulla function
works as part of SNS by producing epinephrine and norepinephrine
in response to low levels of cortisol in the body, the hypothalamus releases what?
corticotropin-releasing hormone (CRH) to anterior pituitary glands
after the anterior pituitary glands receive the corticotropin-releasing hormone (CRH) from the hypothalamus, what do they release?
adrenocorticotropic hormone (ACTH) to the adrenal glands which release cortisol
HPA axis
regulation of cortisol levels
what affect does cortisol have on immune system?
it suppresses it
when prolong cortisol treatment is stopped, this puts a person at risk for what and why?
addisonian crisis because body hasnt needed to produce CRH and ACTH so they arent able to secrete normal amounts of these hormones
mineralocorticoids
aldosterone
Addisons Disease
not enough adrenal cortex hormones (glucocorticoids and mineralocorticoids)
primary adrenal insufficiency
problem is at the adrenal gland
secondary adrenal insufficiency
problem is at the pituitary gland
Addisons disease s/s
hyperkalemia, hypotension, iron overload, hyperpigmentation
ACTH stimulation test result for primary problem
ACTH is given to patient and no increase in cortisol levels =problem at adrenal gland
ACTH stimulation test result for secondary problem
ACTH is given to patient and there is an increase in cortisol levels =pituitary problem
Addisons crisis
acute adrenal insufficiency, cause by trauma, infection, stress
addisons crisis s/s
severe symptoms, shock, death, severe hypotension
primary hyperaldosteronism: Conn’s syndrome and cause
excessive secretion of aldosterone d/t tumor
secondary hyperaldosteronism
stimulated by excessive secretion of renin d/t cushings or congenital causes
Cushings syndrome and treatment
too much cortisol, surgical removal of tumor
ACTH independent hypercortisolism
patient is taking steriods causes increased cortisol levels
Ectopic ACTH hypercortisolism
tumor is somewhere in body causing adrenal glands to produce too muchcortisol
ACTH dependent hypercortisolism
there is a pituitary tumor which is causing too much ACTH secretion which then causes too much cortisol
how to diagnose cushings disease?
24 hour urine free cortisol but still need more testing to confirm like ACTH plasma levels and MRI
Hirsutism
masculine characteristics in females with cushing’s syndrome
what happens to adrenal medulla hormones with hypoglycemia
they increase (epinephrine and norepinephrine)
Alpha 1 receptors
mediate smooth muscle contraction in GI tract, increase glucose
Alph 2 receptors
mediate smooth muscle relaxation in GI tract, decrease insulin secretion
Beta 1 receptors
increase rate and force of heart contraction, stimuate renin release
Beta 2 receptors
relax smooth muscle in bronchi, release insulin and glucagon
Beta 3 receptors
increase lipolysis
Pheochromocytoma
catecholamine-producing tumor found in adrenal gland
treatment of pheochromocytoma
surgery or symptomatic treatment
complications of pheochromocytoma
hypertensive retinopathy, myocarditis, CHF, increased platelet aggregation and CVA
prolactinoma, what gland is affected?
anterior pituitary tumor that causes galactorrhea (milk production), irregular menses, decreased libido in men, decreases bone density
Growth Hormone-secreting Adenoma
Giantism and Acromegaly
Giantism
anterior pituitary problem, too much growth hormone, occurs in childhood BEFORE closure of long bone-can fracture easily, mental status deteriates
Acromegaly
anterior pituitary problem, too much growth hormone, occurs in middle age AFTER closure of long bone, bones thicker, mental status deteriates, hyperglycemia, hypercalcemia
Dwarfism
anterior pituitary gland problem, not enough growth hormone
diabetes insipidus, which gland is affected
posterior pituitary problem, not enough antidiuretic hormone (ADH), polyuria, polydipsia, dehydration
causes of diabetes insipidus
hereditary, trauma, autoimmune, pregnancy, nephrogenic-kidney failure to respond to ADH
Syndrome of inappropriate Secretion of ADH (SIADH) which gland is affected and s/s
posterior pituitary problem, continued release of ADH, weight gain, HTN, AMS
causes of SIADH
tumors, CVA, trauma, pulmonary disorders, drugs, idiopathic
