80 terms

Endocrine Disorders

What is the endocrine system made up of?
-endocrine glands and hormones
-substances released into blood stream
Control systems of body
-nervous system =fast acting
-endocrine system =slow acting
-linked with immune system
What are hormones?
-chemical messengers
-initiate pre-programmed responses in target cells
-on switch that tells cell to carry out response
What are actions of hormones?
1-released by gland/cell
2-circulated in blood stream
3-reach target cell
4-specific action
Hormone action
-must bind with receptors on target cells
-surface or intracellular
-type specific to hormone
What is the reaction time of hormones?
-milliseconds to days
Target cell response varies on what factors?
-number of receptors
-affinity of receptors
Control of hormone levels vary according to?
-diurnal fluctuations (sleep-wake cycle)
-complex cycles (menstrual, pregnancy)
-feedback mechanisms (primarily negative)
Control of hormone output can be in response to?
-levels of substances in blood
-neural stimulus (nerves tell it to)
-hormone stimulus (signal other hormones)
Functions of hypothalamus?
-many functions
-endocrine fxns
Endocrine fxn of hypothalamus
-receive input from multiple sources
-communication with pituitary gland
-releasing factors/hormones
-inhibiting factors/hormones
Pituitary gland
-Master gland
-many hormones, many target cells/tissues
-some directly affect target cell
-others are trophic hormones, which means they signal release of other hormones
What is Growth hormone responsible for?
-bone & mm. growth
-protein synthesis
-fatty acid mobilization
-growth of visceral & endocrine organs, connective tissue
-highest at puberty
Antidiuretic hormone
-acts on kidney
-retains body water level
Thyroid Stimulating Hormone
-trophic hormone affecting thyroid gland
Adrenocorticotrophic Hormone
-trophic hormone affecting adrenal cortex
What is the Hypothalamus-pituitary interaction?
-connection between nervous & endocrine system
-explains how things like emotion, stress & even conscious thought can have an effect on our health
What thyroid hormones are concerned with?
-T3 & T4
What are T3 & T4 responsible for?
-increased metabolic rate
-protein synthesis
-normal growth & development of NS in children
Feedback Look of thyroid gland
T3 & T4>
back to hypothalamus
Parathyroid hormone
-attached to thyroid but not related
What does the PTH do?
-regulate (increase) blood calcium level
Roles of calcium
-mineralization of bone
-normal nerve conduction, mm. contraction
Thymus gland
-thymosin+=hormone that stimulates maturation of T-lymphocytes
-just above the heart
Adrenal glands
-2 components:
adrenal cortex
adrenal medulla
-on top of each kidney
Adrenal cortex
-sex hormones
-sodium & H2O absorption, potassium excretion
-natural, very potent
-anti inflammation
-raises blood glucose
-affects metabolism of all nutrients
Sex hormones
-androgens (DHEA & androstenedione> converted to testosterone & dihydrotestosterone peripherally)
Adrenal Medulla
-epinephrine & norepinephrine
-neurotransmitters for SNS
-fight or flight
-sex hormones
-sex hormone
-androgens (mainly testosterone)
-hormone that signals bone marrow
Genetic testing
-affected individual, family
-imaging like radioscope
How can endocrine disorders affect body fxn?
-growth & development
-fluid & electrolyte balance
-sexual fxn
2 Categories of Endocrine disorders
-Hypofunction = too little
-Hyperfunction = too much
Endocrine Hypofunction
-most common -aging
-congenital defect -drug therapy
-disrupted bloodflow -receptor deficit
-infection -idiopathic
-tumor growth
Endocrine hyperfunction
-excessive stimulation
-hyperplasia or hormone-producing tumor
Endocrine disorders divided into 3 groups
Primary endocrine disorder
-defect originates in gland
Secondary endocrine disorder
-at pituitary gland
-defect in level of stimulating hormone or releasing factor
Tertiary endocrine disorder
-dysfunction of hypothalamus
-both pituitary and target organ understimulated
Pituitary disorders
-remember pituitary is "Master Gland"
-disorders can affect one or more hormones
-hypofxn more common than hyperfxn
-pituitary disorder
-antidiuretic =retaining water
-hypersecretion =produce to much causing hypervolemia
-hyposecretion =dehydrated
Growth hormone
-for normal growth & maturation
GH deficiency in children
Other causes of short stature?
-variants of normal
-intrauterine growth retardation (born small)
-psychosocial (neglect)
-chronic illness & malnutrition
-chromosomal disorder
-skeletal abnormalities
What is the rx for GH deficiency?
-give growth hormone
2 categories of GH excess in adults
-present during childhood
-developed during adulthood
GH excess in children
-variants of normal
-endocrine causes
-genetic/chromosomal disorder
-in adults
-after ephiphyses of long bones have closed
-bones grow larger and thicker
-hands, feet, face, skull
-many other effects t/out body
-andre the giant
Normal roles of T3 and T4
-regulating bodies
-metabolic rate
-increased metabolic rate in almost all body tissues
-most notable: Cardiovascular fxn, GI fxn and Neuromuscular fxn
Hyperthyroidism & cardiovascular fxn
-increased ventilation, HR, blood volume, cardiac output
-feel hot all the time
Hyperthyroidism & GI fxn
-increased appetite
-wt loss
-increased intestinal motility, diarrhea
-too skinny
Hyperthyroidism & Neuromuscular fxn
-fine mm. tremor
-restlessness, nervousness, anxiety, trouble sleeping
Causes of Hyperthyroidism?
-hyperactive thyroid gland
-graves disease
-pituitary or thyroid tumor
Graves disease
-ceased to exist in U.S.
-thyroid stimulation via thyroid-stimulating antibodies
-bug eyes because build up of fluid behind eyes
Thyroid crisis/storm
-rare but life-threatening complication of hyperthyroidism
-very high fever
-extreme cardiovascular & CNS effects
-more common
-decrease in metabolic rate
-autoimmune disease
-disorder of hypothalamus, pituitary, thyroid
-radiation at or near thyroid which is a rx for hyperthyroidism
Hypothyroidism & cardiovascular fxn
-decreased ventilation, HR, blood volume, cardiac output
Hypothyroidism & GI fxn
-decreased appetite
-wt gain
-decreased intestinal motility (constipation)
-not hungry, eat like birds and still gain wt
Hypothyroidism & neuromuscular fxn
-sluggish mental & physical fxn
-somnolence (sleepy)
-cold all the time and require lots of sleep
-non-pitting edema
-puffy face
Congenital hypothyroidism-
-in kids
-can cause permanent mental and growth retardation if not dx'd and rx'd
Rx for hypothyroidism
-give thyroid hormone
Rx for hyperthyroidism
-suppression of thyroid fxn
Role of PTH
-regulate blood calcium
-maintain (elevates) normal blood calcium
Role of calcium
-mineralization of bone
-normal nerve conduction, mm. contraction
What does hyperparathyroidism do to blood calcium levels?
-elevates it, resulting in abnl nerve conduction, mm. contraction and demineralization of bone
-kidney stones
What does hypoparathyroidism do to blood calcium levels?
-decreases it, resulting in abnl nerve conduction, mm. contractions
-hyperactive nerve & mm. fxn
Adrenal cortex hyperfunction
-more common than hypofunction
-Cushing syndrome =too much being produced
Causes of Adrenal cortex hyperfunction
-non-pituitary ACTH-secreting tumor
-iatrogenic =long term steroid therapy
Cushing syndrome manifestations
-musculoskeletal, integumentary, inflammatory/immune, fluid & electrolyte, metabolic, psychologic disturbances
-moon face
-buffalo hump
-increased facial hair in women
Addison's disease
-relatively rare
Etiologies of Addisons disease
-secondary insufficiency due to pituitary or hypothalamic
-withdrawal of steroid rx
-destroying adrenal cortex
Manifestations of Addisons disease
-electrolyte imbalance
-hyperpigmentation of skin (JFK)
-sparce body hair in women
Rx for Addisons disease
-lifelong replacement therapy
-DHEA for women
Endocrine disorders and PT implications
-refer medical workup if:
abnl height
sexual maturity
hair growth or loss
abnl sexual fxn
unexplained wt change
change in appetite or thirst
increase/decrease in metabolic rate of CV, GI or neuromuscular
-reflexes, tone, sensation, tremors,cramps, weakness