chapter 9 - endocrinology Flashcards
what is classic endocrine pathway
when hormones act systemically on a site distant form the gland
what is paracrine pathway
when hormones act locally on adjacent tissue
when is autocrine pathway
when hormones act reciprocally on the gland from which they originated
what is a feedback loop
a circuit of signaling that operates to turn off the release hormone from a gland once the action of the hormone has had its effect
which gland is known as the master gland and why
pituitary, because it produces peptides that regulate the adrenal glands, thyroid glands, ovaries, testes, thereby affecting linear growth, fuel metabolism, water balance, pregnancy, and lactation
what type of prolactinoma does females usually have and what are the symptoms
females usually have microadenomas which cause menstrual irregularities and galactorrhea
what type of prolactinoma do males usually have and what are the symptoms
males usually have macro adenomas which cause impotence and loss of libido. if large enough can cause headache or visual disturbance
what is medical treatment for prolactinoma
bromocriptine (parlodel), pergolide (permax), cabergoline (dostinex)
when can there be mortality risk with prolactinoma
if hypopituitarism develops after surgery or after radiation and is not detected or not treated appropriately
what is treatment for hypopituitarism after surgery, tumor or other cause
replacement with cortisol due to lack of ACTH, thyroid hormone (lack of TSH), estrogen for females and testosterone for males
what are causes for diabetes insipidus
can result from surgery for pituitary lesions, result of lack of antidiuretic hormone (vasopressin)
what is diabetes insipidus
lack of vasopressin which causes hypernatremia
what is treatment for diabetes insipidus
DDAVP (desmopressin)
can diabetes insipidus shorten life expectancy
yes if not adequately treated
what should be underwriting focus for diabetes insipidus
primary etiology of the loss of antidiuretic hormone (pituitary tumor or destructive process)
what is acromegaly and what is the most common cause
rare pituitary disorder cause by a benign tumor that causes growth hormone production.
how can acromegaly manifest
can cause enlargement of feet, hands, mandible, soft tissue swelling, carpal tunnel, HTN, LVH, cardiomyopathy, colon polyps, sleep apnea, glucose intolerance
does acromegaly occur more in males or females
equally in males and females
what is treatment of acromegaly
removal of the tumor
T3 and T4 cause activation of many different cellular processes, including:
increased oxygen consumption, simulation of protein synthesis, enhanced lipolysis, enhanced response to epinephrine and norepinephrine, increased HR and contractibility, increased growth and development
in older individuals hyperthyroidism can trigger ____, so higher risk of _______
atrial fibrillation, embolic event
what is mortality risk with hypothyroidism
myxedema come, but is rare
thyroid cancers will appear how on ultrasound (hot or cold)
will appear hypo functioning or “cold”
where are the adrenal glands located and what is the outer portion called
on top of each kidney, cortex
what are the 3 zones of the adrenal gland
glomerulosa that produces aldosterone, fasiculata that produces cortisol, the reticular that produces androgens
what is at the center of the adrenal gland and what does it produce
medulla, epinephrine and norepinephrine
ACTH from the pituitary affects the production of _____ and ______
cortisol and androgens
what hormones are involved in the fight or flight response
epinephrine and norepinephrine is partially controlled by ACTH, but the main stimulus for secretion if nervous system input that regulates the fight or flight resonse
what is primary hyperaldosteronism and what does it lead to
overproduction of aldosterone by the glomerulosa cells of the adrenal gland, leads to HTN
what are clinical symptoms or primary hyperaldosteronism
low potassium levels, muscle weakness, fatigue, increased urination, increased thirst
what are the 2 most common etiologies of primary hyperaldostonism
aldosterone-producing adenoma and bilateral adrenal hyperplasia
what medication is most commonly used to treat HTN from primary hyperaldosteronsm
spironolactone
is life expectancy normal with primary hyperaldosteronism
yes with normalization of BP
what are symptoms and signs of hypercorticolism
truncal obesity, moon facies, buffalo hump, HTN, striae, hyperglycemia, proximal muscle weakness, amenorrhea, hirsutism, acne, easy bruising, OP, depression, psychosis
what is Cushing’s disease
excess cortisol production as a result of ACTH from a pituitary microadenoa
besides Cushings what are the 2 other etiologies of hypercorticolism
primary adrenal tumor or ectopic production of ACTH (usually from small cell carcinoma of lung)
what is pheocromocytoma
tumor that produces epinephrine and norepinephrine and can be life-threatening
what re symptoms of pheocromocytomas
Headache, perspiration, palps, HTN, cardiac arrhythmias, high output CHF
what do parathyroids produce and what tissues does it act on
produces PTH which regulates serum calcium concentration. PTH acts on multiple tissues but mostly on kidney, bone, intestine and increase serum calcium concentration when levels are low
what is hyperparathyroidism and what is the most common cause
excessive production of PTH, most common cause is single parathyroid adenoma
what are signs/symptoms of hyperparathyroidism
hyperglycemia, polyuria, thirst, abdominal pain, constipation, kidney stones, mental confusion, coma, OP
is there mortality concern with hyperparathyroidism
if followed medically some morbidity and mortality if not followed closely. after surgery most people are cured
what is hypercalcemia of malignancy caused by
elevation of PTH related peptide by a tumor, metastasis to bone, or both
is hypercalcemia of malignancy life threatening why or why not
yes, because onset usually severe and acute, causing cardiac arrhythmias and/or coma.
what is MEN
multiple endocrine neoplasia
name the 6 hormones that are involved in maintaining normal glucose levels
insulin, glucagon, somatostatin, cortisol, epinephrine, growth hormone
what is the fuel for the brain
glucose
where is insulin produced
made and and released from the beta cells of the pancreatic islets
where is glycagon produced
the alpha cells of the pancreatic islets
how do insulin and glucagon interact/relate
insulin is the hormone of the “fed” state, being utilized after ingestion of food to promote its use. glucagon is the hormone of the fasting state, maintaining glucose levels between meals
where is somatostatin produced and what does it do
the delta cells of the pancreatic islets. it inhibits both insulin and glucagon to prevent rapid exhaustion of glucose when a meal is eaten
what is the role of cortisol, epinephrine and growth hormone in maintaining glucose levels
similar to glucagon, maintaining blood glucose in times of stress
what is the cause of DM1 and when is it usually diagnosed
autoimmune destruction of pancreatic beta cells, usual dx before age 21
what is LADA diabetes and at what age is it usually diagosed
latent autoimmune diabetes in adults. dx usually over age 35. initially treated as DM2, but needs insulin, has positive results on testing for at least 2 of the 4 antibodies indicative of diabetes
what is the cause of DM2
insulin is produced bu t peripheral tissues do not respond appropriately. there is insulin resistance.
what is MODY
maturity-onset diabetes of youth. patient might present with acute DKA and need insulin temporarily then can manage with diet, perhaps occasional sulfonylurea drug. can present like DM1 but clinical behavior more like DM2.
what % of females with gestational DM will develop DM2
40-60% over the next 5-10 yrs
what is the mortality rate for diabetic ketoacidosis
10%
what are the acute complications of diabetes
diabetic ketoacidosis (DM1 and MODY), diabetic hyperosmolar coma (DM@) and acute hypoglycemia (All types)
what are chronic complications of diabetes
microvascular disease (retinopathy, nephropathy, neuropathy) and microvascular disease (CAD, carotid artery disease, PAD)
what is the leading cause of adulthood blindness in the USA
diabetes
what is the earliest sign of diabetic nephropathy
microalbuminuria
what is the leading cause of mortality in diabetics
macro vascular disease (CVD - MI)
what are possible symptoms of hypoglycemia
tachycardia, sweating, palms, mental confusion, neurological deficits, coma. can result in death
metabolic syndrome can be made up of combination of what conditions/factors
abd obesity/obesity, elev TG, low HDL, elev BP, elev fasting blood glucose, microalbuiuria
a disease characterized by the destruction of the adrenal glands is:
Addison’s disease
adrenal insufficiency can be caused by….
primary destruction of the adrenal glands (additions disease) or secondary insufficiency (lack of ACTH or exogenous steroid use which suppresses aCTH)
fructosamine reflects avg BG for preceding ______ days
10-20
Which of the following hormones regulate glucose levels?
A. Cortisol
B. Glucagon
C. Insulin
B and C only are correct
Which statement regarding the cortex of the adrenal gland are correct?
A. It is divided into 4 zones
B. The fasciculata produces cortisol
C. The reticularis produces androgens
B and C are correct
Does DM2 have a higher genetic predisposition than DM1?
No
Do African Americans have a higher prevalence than Hispanic Americans for type two diabetes
No
A disease characterized by the destruction of the adrenal gland is
Addisons disease
What is the primary secretary product of the thyroid
T4
