Unit 3 Pathophysiology - Chapter 22 Alterations of Hormonal Regulation Flashcards
Endocrine abnormalities
- decrease in number of receptors
- receptor insensitivity to hormone
- present antibodies against specific receptors
- 2nd messenger defects or postreceptor defects
SIADH (Syndrome of inappropriate antidiuretic hormone)
- abnormally high ADH secretion
- interfere w/ renal free water clearance
- l/t hyponatremia and hypoosmolality
- assocaited with forms of cancer, ectopic secretion of ADH by tumor cells
SX
* oliguria
* concentrated urine (very little output)
* edema + body weight
* pulmonary edema w/ dyspnea and fatigue
* CNS disturbances - n/v, cramps, twitching, lethargy, confusion, seizure, death
DI (diabetes insipidus)
- neurogenic (inadequate response to ADH)
- low ADH secretion
- failure to concentrate urine w/ polyuria and polydispsia
SX
* Polyuria
* dilute urine (pee alot)
* signs of dehydration - hypotension, tachycardia, dry mucuos membrane
* CNS - confusion, dec LOC, irritability
Dipsogenic polydipsa
- compulsory water drinking
- lowers plasma osmolarity to point that it falls below threshold for ADH secretion
Hypopituitarism
- anterior pituitary dysfunction
- failure of hormonal functions
Causes
* pituitary infarction (obstruction of bloodflow)
* space-occupying lesions (tumor or aneurysm)
* surgical removal
* infection
May have these common sx
* short height
* infertility
* cold intolerance
* fatigue
* cannot produce breast milk
Hyperpituitarism
- caused by pituitary adenomas (benign slow growing tumors that arise from cells of the anterior pituitary)
Possible common sx
* weight loss
* heat intolerance
* anxiety
* mnestrual disturbances
* palpitations
Pituitary adenoma complications?
- neurologic and secretory effects
- Pressure from tumors:
1. hyposecretion of cells
2. dysfunction of optic chiasm (l/t visual disturbances)
3. dysfunction of hypothalamus and some cranial nerves
Hypersecretion of GH
- Adults - acromegaly (too much GH, causing bones, cartilage, body organs and other tissues to increase in size) [pituitary adenoma is common cause]
- Children - gigantism
GH deficiency
- Children - growth failure and fastying hypoglycemia
- Adult - fatigue, osteoporosis, and increased mortaility
Thyrotoxicosis
- general condition in which TH levels are elevated produced an exaggerated resposne
- heat intolerance
- palpitations
- anxiety
- fatigue
- weight loss
- muscle weakness
- irregular menses
Hyperthyroidism
- increased circulating TH and stimulation of SNS
SX
* Weight loss
* Increased appetite
* Increased body temp
* Heat intolerance
* Tachycardia
* Palpitations/arrhythmias
* HTN
* diarrhea
* anxiety/irritability/insomnia
* sweating / skin thinning
* hair growth (fine soft hair)
* onycholysis (nail separates from nail beds)
* goiter (enlarged)
* bulging eyes (inflamed eyes)
Graves disease
- form of hyperthyroidism
- caused by thyroid-stimulating immunoglobulins (autoimmune)
- diffuse thyroid enlargement, d/o of skin and eyes
Losing weight without trying.
Fast heartbeat, a condition called tachycardia.
Irregular heartbeat, also called arrhythmia.
Pounding of the heart, sometimes called heart palpitations.
Increased hunger.
Nervousness, anxiety and irritability.
Tremor, usually a small trembling in the hands and fingers.
Sweating.
Changes in menstrual cycles.
Increased sensitivity to heat.
Changes in bowel patterns, especially more-frequent bowel movements.
Enlarged thyroid gland, sometimes called a goiter, which may appear as a swelling at the base of the neck.
Tiredness.
Muscle weakness.
Sleep problems.
Warm, moist skin.
Thinning skin.
Fine, brittle hair
Toxic multinodular goiter and solitary toxic adenoma
Hyperplastic (increased # of cells), hyperfunctioning thyroid nodules autonomously secrete TH — hyperthyrodism and producing sx similar to Graves disease
Toxic multinodular goiter result from multiple fx adenomas
Thyrotoxic crisis
- Thyroid storm
- Often associated with physiologic stress
- W/o treatment, death occurs quickly
Hypothyroidism
- deficient production of TH by thyroid gland
- causes of primary version: iodine deficiency, autoimmune thyroiditis (hashimoto thyroiditis — via cell and antibody-mediated immune processes), subacute or painless thyroiditis (antithyroid antibodies, hyper => hypo, resolve itself within a year?), postpartum thyroiditis, and iatrogenic hypothyrodism (treatment for hyperthyroidism causes suppression of T4 below normal levels)
sx
* Decreased energy metabolism
* thinning hair
* loss of eyebrow hair
* brittle nails
* puffy face
* enlarged thyroid
* dry + coarse skin
* slow heartbeat
* poor appetite
* infertility / heavy menstruation
* constipation
* cool extremities w/ swelling of limbs?
* muscle or joint pain
* weight gain
* poor memroy
* cold intolerance
* feeling of tiredness
* depression + irritabiilty
Hashimoto or autoimmune thyroiditis
Associated w/ lymphocyte infiltration => antibody activation of natural killer celss => induce apoptosis w/ gradual loss of thyroid function => hypothyroid
Subacute thyroiditis
- self limited nonbacterial inflammation of thyroid gland
- damages follicular cells => cause leakage of triiodothyronine (T3) and thyroxine (T4); hyperthyrodism then transient hypothyroidism => corrected by cellular repair and return to normal levels in thyroid
Secondary hypothyroidism
- caused by hypothalamic-pituitary dysfunction in which TRH and TSH are not produced in sufficient amounts
Thyroid carcinoma
- cause ionizing radiation (especially childhood)
Myxedema
- characteristic sign of hypothyroidism
- alterations in connective tissue w/ water-binding proteins
- this excess water l/t thickened mucuos membranes + edema => around eyes and hands/feets (swelling of underlying tissue causing waxy consistency)
- can be life threatening
Congenital hypothyrodism
TH deficieny @ birth d/t thyroid agenesis (total lack)
* hypothyrodism, growth failure, intellectual disability d/t absence of thyroxine
Papillary and follicular thyroid carcinomas
common thyroid malignancies particulary during childhood d/t ionizing radiation exposure
* thyroid nodules present with normal thyroxine levels
Hyperparathyroidism
Greater than normal secretion of PTH
* caused by parathyroid adenoma (primary hyperparathyrodism, usual cause)
sx include:
* chronic hypercalcemia, increased bone resorption (bone breakdown), and hypercalciuria (excess calcium in urine)
* osteoporosis
* kidney stones
* excessive urination
* stomach pain
* tiring easily or weakness
* depression and forgetfulness
* bone and joint pain
* c/o illness no apparent cause
* n/v and no appetite
Secondary hyperparathyroidism
- Compensatory to hypocalcemia
- Often occurs with chronic renal failure or chronic vitamin D deficiency (vitamin D helps with gut absorption of ca++ and maintains optimal serum calcium + phosphate for normal bone mineralization (growth + remodeling by osteoblasts and osteoclasts // without vitamin D bones get brittle or thin)
Lack of vitamin D activation in kidneys d/t CKD l/t hypocalcemia and hyperphosphatemia => compensate via PTH => 2ndary