t/f hypothyroidism is more common in women
what is the significance of thyroid function in children?
critical for normal growth and developement
what is the significance of thyroid function in ADULTS?
major role is to maintain metabolic stability
what two mechanisms hormone production is regulated by?
TSH is under negative feedback control by circulating levels of free thyroid hormone
- Extrathyroidal deiodination of T4 to T3 regulated by nutrition, drugs and illness
what is the normal value of TSH?
0.4 to 4.4
what are the primary etiologies of hyperthyroidism?
- subacutre thyroiditis
what are the secondary etiologies of hyperthyroidism?
- tumor from pituitary or ovary
- pituitary resistance to pit hormones
what are the main drugs that cause hyperthyroidism?
- Interferon ALpha
How is TSH affected in hyperthyroidism?
How is T4 effected in hyperthyroidism?
- Free T 0.8 - 2.7
- Total T4 4.6- 10.9
What OTHER laboratory finding is found in hyperthyroidism?
Thyroid antibody found in graves
What are the neurological ss of hyperthyroidism?
- poor 
- emotional lability
- extreme cases phychosis and mania
What are the reproductive ss of hyperthyroidism?
- Dec libido
- Dec firtility
What are the Gi SS of hyperthroidism?
- Increased peristalsis
What are the metabolic SS of hyperthyroidism?
- Inc apeptite
- weight loss
- inc vitamin utilization
- inc gluconeogenesis
- inc insulin degradation
What are the musculoskeletal ss of hyperthyroidism?
- brisk deep tendon reflexes
- muscle wasting
What are the cardiac ss of hyperthyroidism?
- high output heart failure
What are the integumentary ss of hyperthyroidism?
- warm and moist skin
- execessive sweating
- heat intolerance
- fine hair
- temporary balding
- in graves only pretibial myexodema
What are the ocular ss of hyperthyroidism?
- wide eye stare
- lid lag
Tachycardia, fever, agitation, nausea, vomiting, diarrhea, restlessness, psychosis
How do you treat thyroid storm?
must treat thyroid disorder and underlying cause
What is a CI to RAI?
What is the MOA of PTU and MMI?
Prevent organificaiton and coupling
What are the adverse effects of PTU and MMI?
- Benign transient leukopenia (WBC < 4000) (does not mean that you need to dc therapy)
- Hepatic (usually within the first 3 months of therapy)
- Usually after 6 months-
- pruritic macupapular rash
- lupus like syndrome
How does bb effect hyperthyroidism?
- many of the dx of hpyerthroidism are mitigated by bb (tremor and hr)
- very small effect blocking peripheral conversion of t3 and t4
When is BB the primary mode of tx in hyperthyroidism?
- Adjunctive treatment with PTU or MMI, RAI or iodides
- Primary treatment for thyroiditis or iodine-induced cases where alleviation of symptoms will tide patient over until condition resolves
- Thyroid storm
What are the pts use caution with bb?
- Pre-existing lung disease (especially asthma, COPD)
- Unstable systolic CHF
- Bradycardia or heart block
what is the moa of I?
- Acutely block hormone release and inhibit synthesis of hormone by interfering with intrathyroidal iodide utilization
can make worse if used long term
what is I role in therapy?
- To achieve rapid control if patient is decompensated
- In preparation for thyroid surgery (due to decrease in size and vascularity of the gland)
- Following RAI to prevent rapid hormone release after gland destruction
What are the pts that should consider surgery?
- large gland
- severe pohthalmopathy
- or lack or remission on antithyroid drug
what is a main disadvantage of rai?
cannot have human contact for 1 week, cannot sleep in the same bed as someone and not rec to be standing next to someone for more than 5 mins
What are the lab values for overt hypothyroidism?
What are the lab values for subclinical hypothyroidism?
What are the neurologic ss of hypothyroidism?
- slurred speech
What are the endocrine ss of hypothyroidism?
increased prolactin levels
What are the hematologic ss of hypothyroidism?
What are the reproductive ss of hypothyroidism?
- alteration in sex hormones
- decreased libido
What are the cv ss of hypothyroidism?
- Dec sv hr co with INC PVR to maintain bp
- may lead to cardiomegaly
- distant heart sounds
What are the pulmonary ss of hypothyroidism?
- Pleural effusion
- late stage may lead to co2 retention
What are the renal ss of hypothyroidism?
- Dec renal blood flow
- dec gfr
What are the gi ss of hypothyroidism?
- weight gain
- dec glucose absorption and delayed uptake
- inc sensitivity to insulin
- elevated serum lipids
What are the musculskeletal ss of hypothyroidism?
- muscle aches and stiffness
- slow movement
- slow dtr
- aching stiff joints
what are the integumentary ss of hypothyroidism?
- dry flakey skin
- brittle head and body hair
- dec hair and nail growth
- cold intolerance
What are the other ss of hypothyroidism?
- non pitting boggy edema
- hoarse voice
- may have goiter
What ss is present with severe hypothyroidism?
What are the characteristics of myexedema coma?
- medical ER
- diminished consciousness
- hypothermia without shivering
- lactic acidosis
- precipitated by illness, stroke, medications, ER situations
What are the two complications of hypothyroidism?
what are the characteristics of cretinism?
- absence of thyroid tissue or hormone
- child will be dwarfed with short limbs, and mentally challenged
What are the treatments of hypothyroidism?
- remove drug-related causes initially
- replace thyroid hormone
what is the prognosis of hypothyroidism?
- if adequately treated and monitored, good
- requires lifelong supplementation and mx
- needs fluctuate with pregnancy (inc) and age (decrease)
what are the three classes of medications available for hypothyroidism?
what is liothyronine's role in therapy?
- only T3
- twice daily
- not recommended over levothyroxine
- no advantage of t3 alone
- worse adverse effects (long term)
- increase risk of hyperthyroidism
- use in certain deiodinase gene polymorphisms
What is levothyroxine's role in therapy?
- only T4
- bioequivalence in all generics and brands
- well tolerated
- over tx occurs in 20% of pts
- over tx = cv AE, skeletal effects, possible affective disturbances
what is dosing for levothyroxine?
- slam with full dose (1.6 to 1.7 mcg/kg/day)
- or titrate - inc by 12-25 mcg every 6 wks
Drug interactions that dec levothyroxine uptake?
- calcium products
dg interactions that inc clearance of levothyroxine?
what is liotrix's place in therapy?
- T3 + T4
- same issues as liothyronine
what is armour thyroid's place in therapy?
not recommended in tx of hypo or for use over levothyroxine
what are neutraceutical's (traic, triatricol) place in therapy?
- not considered a remedy for hypo
- may contain iodine or sympathomimetic amines