Endocrine Flashcards
_____________ secretes releasing hormones and inhibiting hormones that control anterior pituitary.
Also synthesizes vasopressin and oxytocin which go to the posterior pituitary
Hypothalamus
Originate in the target organ
Primary Disorder
Originate in the pituitary, causing a problem in the target organ (pituitary adenoma)
Secondary Disorder
Originate in hypothalamus and cause a problem in both the pituitary and the target organ (irradiation to the brain)
Tertiary Disorder
ADH released by the post. pit. in response to:
- Decrease in blood volume
- Decrease in BP
- Increase in osmolarity of body fluids
Actions of ADH
- Water re-absorption in the kidney
- Direct vasoconstriction
- Rise in arterial pressure (short term)
- Failure of neg. feedback mechanism that regulates ADH secretion
- Too much ADH secreted
- Caused by activation of baroreceptors in carotid arteries, cardiopulmonary receptors
Syndrome of Inappropriate ADH Secretion (SIADHS)
Etiology: Lung tumors, stressful conditions, TB, pneumonia, positive pressure breathing
S/Sx of SIADHS
Increased water retention and dilutional hyponatremia
Diagnostic test: Low serum Na+ and high specific gravity
Inadequate ADH secretion
Inability of kidneys to reabsorb water
Causes: Neoplastic or inflammatory processes (cancer, abscesses, meningitis), surgical or radiation injury, severe head trauma, intracranial surgery
Diabetes Insipidus
Treat with vasopression or desmopressin
S/Sx of D.I
Diagnostic Test
Polyuria (3-20L/day)
Intense thirst and polydipsia
Dryness of mouth and skin
Hypertonic dehydration
Urine will be pale and dilute, increased serum osmolality, hypernatremia
Hyposecretion of Growth Hormone
Can cause short stature in children
Treatment: GH injections (recombinant DNA therapy)
Hypersecretion of Growth Hormone
- results in gigantism in children due to pituitary adenoma
- in adults, causes acromegaly (increase in bone size, voice deepening, vertebral changes, glucose intolerance, enlargement of heart*)
Iodine attaches tyrosine molecules to form _________ and _________
thyroxine (T4) and triiodothyronine (T3)
T4 –> T3 before it can act
________ - lowers blood calcium levels by inhibiting the release of Ca from bones
Calcitonin
Most common endocrine disorder after diabetes
Most cases primary
Hypothyroidism
Hashimoto’s thyroiditis - autoimmune
(Congenital - cretinism)
Primary hypothyroidism
Elevated TSH and low T3, T4
Myxedema (puffiness of face and swelling around eyes) coma-severe and life-threatening
Pharm treatment for hypothyroidism
Levothyroxine (T4) (Synthroid)
Low secretion of TSH from pit. and high T3, T4 levels
Hyperthyroidism
Less common than hypothyroidism
-Grave’s Disease (Autoimmune): exophthalmos, diffuse goiter, thyrotoxicosi
Extreme hyperthyroidism, rarely seen due to improved diagnosis and treatment
Thyroid Storm aka Thyroid crisis
___ secretion pulls calcium from the body stores (bones) and diet to increase calcium serum levels
Parathyroid hormone (PTH)
- Effects: Loss of bone calcium due to excessive osteoclast activity, resulting in hypercalcemia
- Assessment Findings: Bone weakness (increased risk of fracture, deformity, and pain), muscular and neurological symptoms, kidney stone formation
Hyperparathyroidism
Etiology- parathyroid tumor, gland hyperplasia, autoimmune
Hypocalcemia
-Assessment findings-increased neuromuscular excitability, cardiac effects, skeletal effects (if deficiency is long-term)
Hypoparathyroidism
Hypocalcemia can cause a
Trousseau’s Sign
Primary adrenal insufficiency
Destruction of all layers of the adrenal gland
Autoimmune (most common)
Addision’s Disease (hyperpigmentation - bronzing due to elevated ACTH)
Life-threatening process
7-14 days; need lifelong replacement of affected hormones
Results in low _____ ______ levels, elevated ____ levels due to lack of feedback inhibition
adrenal cortisol
ACTH
Rapid withdrawal of glucocorticoids
Secondary Adrenal Cortical insufficiency
etiology: hypopituitarism, removal of pituitary
Excess production of ACTH by pituitary tumor
Cushing Disease
_____ ___: Excessive cortisol production caused by an adrenal tumor
Adrenal form
_____ ________: caused by a nonpituitary ACTH secreting tumor
Cushing syndrome
Hyperaldosteronism
Renal retention of sodium and water; loss of potassium
Primary: Aldosterone-secreting adenoma
Secondary: Renal ischemia which activates the Renin-Angiotension-Aldosterone mechanism (RAAS)
Excess catecholamine secretion (epinephrine and norepinephrine)
Adrenal medulla hypersecretion (PHEOCHROMOCYTOMA)
