Endocrinology Flashcards
Secrete products into blood or extracellular spaces
Endocrine glands
Secrete products through ducts into internal or external spaces
Exocrine glands
What are the basic functions of the endocrine system?
- Regulation of digestion, use and storage of nutrients
- Growth and development
- Electrolyte and water metabolism
- Reproduction
What are the major glands of the endocrine system?
- Pituitary gland (AP, PP)
- Thyroid
- Parathyroid
- Adrenal
- Pancreas
- Gonads
Controlled by factors released from the hypothalamus into portal blood vessels (Releasing factors)
Anterior pituitary gland
What are the cells of the AP? What do they secrete?
- Somatotrophs; GH
- Lactotrophs; Prolactin
- Corticotrophs; ACTH
- Thyrotrophs; TSH
- Gonadotrophs; LH and FSH
What does growth hormone do?
Increases glucose levels in the blood (glucose regulation); causes growth
What does prolactin do?
Lactation and immune regulation
What does ACTH do?
Stimulates cortisol secretion from adrenal cortex, stress response
What does TSH do?
Release thyroid hormone from thyroid gland
What does LH and FSH do?
Regulates reproduction and gonadal steroids
Contains the nerve terminals of axons from neurons located in the hypothalamus
PP
What are the hormones released by the PP?
- Oxytocin
2. Vasopresson (ADH)
What does Oxytocin do?
- uterine contraction (Pitocin), lactation
2. Facilitates interactions between people
What does vasopressin do?
Causes reabsorption of water from renal tubules
When TSH stimulates the thyroid gland, what does it secret?
- Thyroid hormone (TH - T3, T4) from follicular cells
2. Calcitonin from C-cells
What does TH do?
Regulates basal metabolism
What does calcitonin do?
Moves calcium out of the blood into bones
What stimulates the release of PTH?
Decrease in Ca levels in the blood
What does PTH do?
Moves calcium out of bones into the blood
What are the two main parts of the adrenal gland?
- Cortex (outer)
2. Medulla (inner)
What are the 3 layers of the adrenal gland? What do they secrete?
- Zona granulosa; mineralcorticoids (aldosterone)
- Zona fasciculata; Glucocorticoids (cortisol)
- Zona reticularis; sex steroids (estrogen, androgens, progestins)
What is the function of aldosterone?
Stadium and potassium homeostasis
What is the function of cortisol?
Carbohydrate metabolisme and modulate inflammation
What is the function of gonadal steroids?
Regulate tissues responsive to gonadal steroids
What is the medulla controlled by? what does it secrete?
Sympathetic nervous system; NE and epinepherine
What are S and S of endocrine dysfunction?
- RA
- Muscle weakness, atrophy myalgia and fatigue
- Carpal tunnel syndrome
- Other musculoskeletal disorders
What are 3 main consequences of AP disorders?
- Hyperpituitarism
- Hypopituitarism
- Local compression of brain tissue
What are the effects that can result from hyperpituitarism?
- Can compress adjacent brain and nervous tissues
- Visual field abnormalities – bitemporal hemianopsia
- Headaches
- Somnolence - sleepiness
- GH – Gigantism, Acromegaly
- Prolaction – hyperprolactinemia
- ACTH – Cushing’s disease
- TSH – hyperthyroidism
Disease due to increased GH secretion before epiphyseal plates close; develops abruptly; increased height; tx: surgery, radiation, drugs
Gigantism
Disease due to increased GH after epiphyseal plates have closed; gradual onset
Acromegaly
What are S and S of acromegaly?
- Thickening of bones
- Hypertrophy of soft tissues;
Specific effects of hormone = Primarily of face, skull, hands and feet; Coarsening of facial features, protrusion of jaw, thickened ears, nose and tongue, broadening of hands with spade-like fingers
Non specific effects of tumor = Headaches, diplopia, lethargy and blindness
What are post-op care precautions to take with Gigantism and acromegaly?
- Encourage ambulation and walking within 24 hours post surgery
- Coughing, sneezing, and blowing nose contraindicated
- Monitor blood glucose levels
- Intracranial pressure
- Possible visual changes
- Unexpected mood changes
What are the S and S of hyperprolactinemia?
Women:
- Galactorrhea – increased secretion of milk (not while breastfeeding)
- Amenorrhea
- Depressed libido
- Decreased fertility
- Hirsutism (excessive hair growth)
Men:
- Loss of libido
- Impotence
- Decreased fertility
What are some of the physical therapy needs of patients with hypopituitarism?
- Visual deficits
- Infection control – skin care
- Weakness
- Fatigue
- Lethargy and apathy
- Orthostatic hypotension
What disease occurs with hypopituitarism of the PP?
Diabetes insipidus (ADH deficiency)
What are the manifestations of diabetes insipidus?
- Kidney tubules fail to reabsorb water
- Polyuria - nocturia (fatigue and irritability result)
- Polydipsia
- Dehydration
What disease occurs with hyperpituitarism of the PP?
Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH)
What are the manifestations of SIADH?
- Hyponatremia
- CNS dysfunction
- Water retention
What would PTs need to be aware of with someone who has SIADH?
- Changes in urination
- Headache
- Muscle cramps
- Restlessness or irritability
- Weight gain (> 2 pounds per day)
- Convulsions
What disease commonly occurs with hyperthyroidism?
Graves disease (more common in women)
What are S and S of thyroid storm?
- High fever
- Severe tachycardia
- Delirium
- Dehydration
- Extreme irritation or agitation
What are thought to be the causes of hyperthyroidism?
- Immune
2. Genetic
__% of people with Grave’s disease have antibodies that increase the size of gland and hormone secretion
95
What are the manifestations of hyperthyroidism?
- Nervousness
- Heat intolerance
- Weight loss despite increased appetite
- Proximal m. weakness accompanied by atrophy
- Respiratory muscle weakness
- Chronic periarthritis
- May induce atrial fibrillation, precipitate congestive heart failure, and increase risk of underlying coronary artery disease for MI
What are the treatments for hyperthyroidism?
- Radioactive iodine
- Drugs
- Surgery
Why would a person with hyperthyroidism be treated with radioactive iodine?
It is taken up in the thyroid gland and kills cells; pts usually treated with thyroid hormone replacement
As a PT, what do you need to be aware of with someone who has hyperthyroidism?
- Problems with balance and coordination due to proximal muscle weakness
- Exercise intolerance
- Impaired cardiopulmonary function
- Dyspnea due to weak respiratory muscles
- Heat intolerance
- Fatigue
What is the most common thyroid disorder?
hypothyroidism
What are manifestations of hypothyroidism?
- Generalized slowing of metabolic rate
- Fatigue
- Mild cold intolerance
- Weight gain (10-15 lbs)
- Forgetfulness
- Depression
- Dryskin or hair
What are therapy concerns with a pt who has hypothyroidism?
- Skin breakdown – dry and edematous
- Be aware of cardiovascular system on patient with hormone replacement
- Rhabydomyolysis in untreated patients – breakdown of skeletal muscle (unexplained muscle pain and weakness) – can lead to renal failure
Enlargement of the thyroid gland associated with hyper and hypothyroidsm
Goiter
What are the causes of goiter?
- Iodine deficiency - hypothyroidism
- Inflammation
- Tumor (benign or malignant)
- Sometimes in hyperthyroidism, especially Grave’s disease
What are S and S of thyroid tumors?
Hard, painless nodule in thyroid gland
In blood, TH [increases/decreases] Ca blood serum levels while it [increases/decreases] phosphate blood serum levels.
Decreases; increases
[Primary/ Secondary] thyroid disorders are caused by decrease in hormone secretion of the pituitary or hypothalamus. [Primary/ Secondary] thyroid disorders are cause by the thyroid not making enough hormones.
Secondary; primary
What are S and S of hypothyroidism
- cold intolerance
- dry skin and hair
- fatigue
What are manifestations of hyperparathyroidism?
- Bone demineralizations
2. Hypercalcemia
What are S and S of hypercalcemia?
- Peptic ulcers
- Abdominal pain
- Pancreatitis
- Kidney damage – kidney stones
- Chronic low back pain
- Bone fractures
- Marked muscle weakness and atrophy
What are indications of hypoparathyroidism?
- Hypocalcemia
- High serum phosphate levels
- Possible neuromuscular irritability (tetany)
What are clinical manifestations of hypoparathyroidism?
- Neuromuscular irritability
(Tetany, Spreads and becomes more severe, Chvostek’s sign – facial twitch when facial nerve is tapped) - Cardiovascular effects (Arrhythmias, Eventual heart failure)
What are primary diseases of the Adrenal gland?
- Addison’s disease (adrenal insufficiency)
- Decreased cortisol
- Decreased aldosterone
- Conn’s syndrome (increased aldosterone)
What are risk factors for addison’s disease
- Surgery
- Pregnancy
- Accident
- Infection
- Salt loss due to excessive sweating (diaphoresis)
- Failure to take steroid therapy
- Acute steroid withdrawal
What are S and S of decreased cortisol?
- Hypoglycemia (weakness, weightless, nausea)
- Emotional disturbances
- Diminished response to stress
What are S and S of decreased aldosterone?
- Increased sodium excretion
- Craving for salty food
- Dehydration (hypovolemia)
- Hypotension
- Decreased cardiac output
Primary aldosteronism; hyper secretion of aldosterone from adrenal cortex
Conn’s syndrome
What manifestation occurs in primary adrenal insufficiency that does not occur in secondary adrenal insufficiency?
Hyper pigmentation (due to increased ACTH)
What are additional symptoms seen in secondary adrenal insufficiency that are not seen in primary?
- Arthralgias
- Myalgias
- Tendon calcification
Disease caused by hyper secretion of glucocorticoids resulting in excessive exogenous glucocorticoids
Cushing syndrome
Generalized muscle weakness due to muscle wasting, osteoporosis, poor wound healing, thinning of skin, hyperglycemia, truncal obesity, moon-shaped face, Buffalo hump, Virilism in women, and mental changes are all manifestations of what disease?
Cushing syndrome
Conditions that reduce renal blood flow, induce renal hypertension, and edematous disorders (cardiac failure, cirrhosis) can all result in
Secondary hyperaldosteronism
Hypernatremia, hypervolemia, hypokalemia, metabolic alkalosis, hypertension (heart failure, renal damage, CVA), muscle weakness, intermittent, flaccid paralysis, paresthesias, cardiac arrhythmias, polyuria, polydipsia, diabetes mellitus, and metabolic alkalosis (tetany, respiratory suppression) are manifestations of…
Secondary hyperaldosteronism
What hormone receptors are targeted for drug therapy of the endocrine system? where are they located?
- Surface membrane receptors; on cell membrane
- Cytosolic hormone receptors; in cell plasma (steroid hormones)
- Nuclear hormone receptors; in nucleus (thyroid hormones)
What drugs are used to treat hyperthyroidism and actually decreases TH?
- Antithyroid drugs (propylthiouracil, methimazole)
- Iodide
- Radioactive Iodide
What drugs are used to treat hyperthyroidism to decrease the symptoms of excessive TH?
Beta-adrenergic blockers (end in OLOL)
What drugs are used to treat hypothyroidism?
- Levothyroxine (synthetic T4, end it THROID)
- Liothryosine ( cytomel, synthetic T3)
- Liotrix (thyrolar, synthetic T3 and T4)
- Thyroid (amour thyroid, others, natural T3 and T4)
Who are treated with thyroid hormone?
- Children with hypothyroidism
- After treatment with radioactive iodine
- Impaired synthesis of thyroid hormone
- Patients with thyroid cancer or goiter
- Early stages of hypothyroidism
Besides PTH, VitD, and calcitonin, what hormones for calcium homeostasis are used catabolically? Anabolically?
Catabolic = breakdown of bones; 1. Glucocorticoids 2. Prostiglandins Anabolic = buildup of bones; 1. Estrogens, androgens 2. GH 3. Insulin 4. TH
What conditions would you use calcium supplementation to treat?
- Osteoporosis
- Osteomalacia
- Rickets
- Hypoparathyroidism
What conditions would you use VitD supplementation to treat?
- Postmenopausal osteoporosis
- People who aren’t getting enough VitD
- Bone loss caused by glucocorticoids
What are initial S and S of VitD toxicity (can build up in body due to fat solubility)?
- Headache
- Increased thirst
- Decreased appetite
- Metallic taste
- Fatigue
- GI disturbances
What are prolonged S and S of VitD toxicity?
- Hypercalcemia
- Hypertension
- Renal failure
- Cardiac arhythmias
- Seizures
- Potentially death
What drugs are used to inhibit the breakdown of bone?
Biphosphonates (fosamax, dirdronel, pamidronate)
Disorder where there is a rapid turnover of bone
Paget disease
What drugs are used to decrease blood calcium levels and increase of bone mineralization?
Calcitonin (cabicalcin - synthesized) (calcimar, miacalcin - extracted from salmon)
What are the uses of biphosphonates?
- Heterotopic ossification
- Prevent hypercalcemia in cancers where bone is being broken down
- Decreased bone loss from glucocorticoids
- Paget disease
- Postmenopausal osteoporosis
What are the uses of calcitonin?
- Paget disease
- Hypercalcemia
- Postmenopausal osteoporosis
- Bone loss from glucocorticoids
What is the role of estrogen?
Protects bone mineralization in women
What are the risks of using estrogen therapy?
- Increase of CV diseases
2. Increase risk of cancer -Primarily reproductive system cancers
Estrogen therapy that selectively inhibits one receptor at one site
Selective estrogen receptor modulator (SERM)
SERM drug that increases risk of uterine cancer while treating bone osteoporosis.
Tamoxifen
SERM drug that acts like estrogen at the bone, improves lipid panel in CV system and does not increase the risk of breast and uterine cancer
Raloxifene