Endocrine Flashcards
What is Addison’s disease?
A relatively rare disease occurring in those aged 30-60 (more common in women) that is caused by autoimmune mechanisms that destroy adrenal cortical cells– decrease in glucocorticoids, mineralocorticoids and androgen
Inadequate corticosteroid and mineralocorticoid synthesis and elevated serum ACTH
Before clinical manifestations occur, more than 90% of total adrenocortical tissue must be destroyed
Decreased BG (mostly in kids), fatigue, weight loss, hyponatremia and salt craving, hyperkalemia, hypotension, skin changes and hair loss (women)
What is the emergency treatment for adrenal crisis?
- establish large bore IV access
- draw blood for immediate serum electrolytes and glucose
- infuse 2-3L of NS or 5%DNS bolus (depending on BG level) monitor for FVE during tx
- hydrocortisone loading dose (bolus) followed by lower dose q6h (or continuous)
Define acromegaly
A condition most often caused by a somatotroph (growth hormone secreting) adenoma of the pituitary gland. Prolactin can also be secreted in excess.
manifestations:
-enlarged hands, feet, jaw, nose, protruding forehead, enlarged tongue
-excess prolactin– amenorrhoea (no period), unexpected lactation, erectile dysfunction and loss of libido
-if not treated, can reduce life expectancy as it increases risk for cardiovascular disease, diabetes and some cancers
Where is growth hormone secreted from?
pituitary gland
Define giantism
acromegaly that occurs in children/adolescents
What happens with hyposecretion of ADH?
-diabetes insipidus– think dry inside
-increases urine output (with extreme thirst), loss of fluids result in increased blood osmolality and hypernatremia (hemoconcentration), and there is also a loss of K+ (hypokalemia)
NOTE: psychogenic DI does not lead to these lab imbalances
What happens with hypersecretion of ADH?
-syndrome of inappropriate antidiuretic hormone (SIADH)
-think “soggy inside”
-decreased urine output, retention of free water resulting in dilutional hyponatremia and ++concentrated urine
What does SIADH stand for?
Syndrome of inappropriate antidiuretic hormone– from hypersecretion of ADH
What is T4
Thyroid hormone
What happens when T4 is low?
increase in TSH
What happens with high T4?
decrease in TSH
What does thyroid effect?
metabolism
What are the symptoms of hypothyroidism (Hashimoto’s)?
-decreased metabolic processes
-fatigue, bradycardia, constipation, weight gain, dry skin, brittle hair and nails, cold intolerance
can turn into Myxedema crisis
What are the symptoms of hyperthyroidism (Graves)?
-increased metabolic processes
-nervousness, tachycardia, diarrhea, weight loss, fine hair, diaphoresis, heat intolerance
Can turn into thyroid storm
What is a thyroid storm?
Extreme hyperthyroidism
Sx: tachycardia, HTN, hyperthermia, seizures, delirium, coma
managed with: beta blockers, thioamide (antithyroid), iodine solution, corticosteroids
What is the diagnosis if the serum TSH is normal? high? low?
normal– no further testing needed
high– free T4 added to determine the degree of hypothyroidism
low– free T4 and T3 added to determine the degree of hyperthyroidism
REMEMBER: low TSH is hyperthyroidism and high TSH is hypothyroidism
Hyperthyroidism results in ___ TSH
low
Hypothyroidism results in ___ TSH
high
Describe the radioiodine uptake test
-only relevant to hyperthyroidism
-radioactive iodine ingested which will be taken up by the thyroid gland
-images examined to see degree of uptake to determine cause
-high iodine uptake=hyperthyroid
-low uptake-the gland is no longer producing high levels of thyroid hormone
What do Thyrotropin receptor antibodies determine?
the etiology of hyperthyroidism
-Graves’ disease is caused by autoantibodies to the TSH receptor
-may be used in pts that cannot take radioactive iodine
What is TSH?
Thyroid stimulating hormone
What contraindications are there for using radionuclide imaging?
pregnancy and breastfeeding
What is the biggest misconception about iodine?
that being allergic to shellfish means that you are allergic to iodine
Describe thyroid ablation
radioiodine taken by capsule (or liquid) with the purpose of causing tissue damage
-pt will have to be on levothyroxine for the rest of their life as replacement therapy
What is aplastic anemia?
all blood cells are low and is commonly a side effect of medications
Define hypercalcemia
too much calcium in the blood
What does the parathyroid effect?
regulates calcium and phosphate levels
What are the clinical manifestations of hypercalcemia?
Stones– calcium-based kidney stones or gallstones
Thrones– polyuria
Bones– osteoporosis
Groans– constipation and muscle weakness
Psychotic overtones– mental status changes
Describe the relationship between hyper-PTH and secondary osteoporosis
too much Parathyroid hormone causes calcium to be taken out of the bone storage, causing osteoporosis
What is Paget’s disease?
Chronic, progressive genetic disease that leads to osteolytic and osteoblastic activity– disorganized reformation of bone that is structurally abnormal and prone to fracture
-pts may experience bone pain, arthritis and deformities
How should bisphosphonates be taken? NCLEX question
taken in the morning before eating with a cup of water and pt should remain sitting up for 30 min post administration
Define dyspepsia
indigestion– stomach pain, heart burn, burping
How often should bone mineral density (BMD) be evaluated?
at baseline and every 1-3 years on treatment
What is the interaction between Raloxifene and Levothyroxine?
Raloxifene lowers absorption of levothyroxine
Describe Trousseau’s sign
when a BP cuff is inflated it causes a carpal spasm
Describe Chvostek’s sign
tapping cheek will cause it to twitch
What is Cushing’s disease?
Pituitary hypersecretion of ACTH– chronic excess corticosteroid levels
DIFFERENT from Cushing’s syndrome which can be caused by administration of too much glucocorticoids or a tumor
What is the treatment of primary Cushing’s?
-surgical removal of tumor
-pharmacological
What is the treatment of iatrogenic Cushing’s?
-use minimum dose required and try alternative day dosing to minimize side effects
What is the treatment for Addison Disease?
Glucocorticoid: hydrocortisone, short acting
Mineralocorticoid: fludrocortisone, salt additives for excess heat and humidity, increased dose of glucocorticoids for stress situations
What causes Adrenal crisis?
long-term corticosteroid that is suddenly discontinued
corticosteroid needs to be tapered off because adrenal glands slow down/atrophy and need time to start up again
What are the symptoms of adrenal crisis?
hypotension, tachycardia, dehydration, hyponatremia, hyperkalemia, hypoglycemia, fever, weakness, and confusion
What does Growth hormone do?
regulates anabolic processes related to growth and adaptations to stressors
-promotes skeletal and muscle growth (why body builder’s inject it)
-increases protein synthesis
-increase liver glycogenolysis (glycogen in liver is broken down into glucose)
-increases fat metabolization (fat stores are released and used as energy)
What are the 3 types of Diabetes Insipidus?
central, nephrogenic and psychogenic
How is SIADH diagnosed?
a diagnosis of exclusion– consider pt history and rule out other causes of hyponatremia AND compare urine and serum osmolality (is serum osmolality is lower than urine osmolality, it supports SIADH)
What is the treatment of SIADH?
-treat underlying trigger if possible
-only severe hyponatremia (<120mmol/L) is corrected with hypertonic fluid
-primary tx is fluid restriction of about 800-1000mL/day
-oral solutes may be added (extra salt) and a loop diuretic io increase UO
What are some acquired causes of thyroid imbalance?
-imbalances in iodine intake (low=hypothyroid, excess=hyperthyroid)
-medications (ex. amiodarone can cause both hypo and hyper)
What is Myxedema crisis (coma)?
Sx: hyponatremia, hypoglycemia, hypothermia, hypotension, hypoventilation and loss of consciousness
Causes: infection, MI, severe cold exposure, trauma, sedating meds and OPIOIDS of severe, longstanding hypothyroidism
Management: supportive to maintain perfusion IV fluid resuscitation, vasopressors, maintain ventilation, dextrose infusion, passive warming, IV levothyroxine loading dose q8h, IV hydrocortisone until adrenal insufficiency ruled out
What does the parathyroid do?
responsible for the regulation of calcium and phosphate levels
What are the clinical manifestations of hypercalcemia?
stones– kidney or gallstones
thrones– polyuria
bones–osteoporosis
groans– constipation and muscle weakness
psychiatric overtones– mental status changes
parathyroid gland regulates calcium levels in the body
Describe Primary Hyperparathyroidism (H-PTH)
A tumor leads to excess PTH release that is not responsive to normal negative feedback signal
-hypercalcemia
-hypophosphatemia
treated by removing tumor
-maintenance of the airway is vital post-op (trach kit at bedside)
-hypocalcemic crisis (tetany, seizures, laryngospasm)
What are the signs and symptoms of hypocalcemia?
-photophobia
-mental status changes
-tetany (neuromuscular irritability/twitching)
-paresthesia
-bronchospasm
-laryngospasm
-arrhythmias
