How is thyroid hormone transported in the body?
Thyroxine binding globulin (TBG)
are bound or unbound hormones active?
unbound to plasma proteins (the free hormones)
Is T3 or T4 more active?
T3 is 4x more active than T4
What do thyroid hormones regulate?
energy, heat production, growth, facilitate CNS, metabolism
What is primary thyroid dysfunction?
when the dysfunction occurs and the gland itself
What is secondary thyroid dysfunction?
When the dysfunction occurs are the pituitary gland
What controls thyroid gland function?
Thyroid stimulating hormone, which is a glycoprotein synthesized in the anterior
pituitary gland
When are TSH levels the highest?
during sleep
Explain the process of how T3 is produced
The body can sense a decrease in T3 levels, and sends a signal to the brain. The
hypothalamus receives the signal, and makes TRH (thyrotropin releasing hormone). TRH
then travels to the anterior pituitary, and signals TSH (thyroid stimulating hormone) to
be made. TSH then travels to the thyroid and tells the thyroid to produce more T4,
which is converted to T3 in peripheral sites in the body
, What is tertiary thyroid dysfunction?
When the dysfunction occurs at the hypothalamus
What is the most common cause of thyroid disease?
autoimmune disease
What is hypothyroidism?
reduction in amount of circulating free thyroid hormone (T4)
What are risk factors for hypothyroidism?
family history, females, other autoimmune diseases, treatment for hyperthyroidism,
amiodarone, lithium, age over 40
How often should females over 40 get TSH checked?
annually
What are the s/s of hypothyroidism?
lethargy, weight gain, swelling of hands and feet, periorbital edema, coarse skin, hair
loss, delayed deep tendon reflexes, constipation, hyperlipidemia
What testing is needed for hypothyroidism?
TSH, wise to get a lipid panel due to hyperlipidemia it causes
How do you interpret TSH levels for hypothyroid?
TSH will be high, T4 will be low
subclinical hypothyroid will have elevated TSH and normal T4
What is the effect of maternal hypothyroid in a pregnant woman?
baby cannot produce their own thyroid hormone until 2nd trimester...so if mom has a