Term
|
Definition
-regulate growth and development
-regulate body temperature
-regulate energy levels |
|
|
Term
|
Definition
1. periventricular nucleus of hypothalamus releases TRH
2. TRH acts on pituitary to release TSH
3. TSH acts on thyroid gland to release T4 and T3 |
|
|
Term
| actions of thyroid hormones |
|
Definition
-nuclear receptors
-stimulation of gene transcription
-receptors present in virtually all tissues
-affect overall development
-affect overall metabolic rate |
|
|
Term
| effects of thyroid hormones |
|
Definition
-determine development
-metabolic regulation |
|
|
Term
| Fetal hypothyroidism results in _______. |
|
Definition
|
|
Term
| What is the key parameter to know when testing thyroid function? |
|
Definition
| free hormone available for action |
|
|
Term
| adult mild hypothyroid state |
|
Definition
|
|
Term
| adult severe hypothyroid state |
|
Definition
|
|
Term
| hypothyroid state at birth |
|
Definition
|
|
Term
| enlargement of the thyroid gland |
|
Definition
|
|
Term
| What is non-goitrous hypothyroidism caused by? |
|
Definition
|
|
Term
| Why are TSH levels elevated in hypothyroidism? |
|
Definition
| feedback inhibition by T4 and T3 is decreased, so pituitary kicks out more TSH to try to compensate |
|
|
Term
| Free T4 and T3 levels are increased/decreased in hypothyroidism. |
|
Definition
|
|
Term
| objective of replacement therapy for hypothyroidism |
|
Definition
| attain and maintain a normal thyroid hormone level |
|
|
Term
| What type of patients must be given gradual increments of thyroid hormone replacement therapy and be carefully monitored? |
|
Definition
| those with cardiac problems |
|
|
Term
| side effects of replacement therapy for hypothyroidism |
|
Definition
cardiac arrhythmias
osteoporosis |
|
|
Term
| drug of choice for hypothyroidism |
|
Definition
levothyroxine sodium (T4)
Synthroid, Levothyroid |
|
|
Term
| What drug for hypothyroidism is more potent, has a shorter half life, and is more expensive than levothyroxine? |
|
Definition
|
|
Term
| What hypothyroidism drug has a T4:T3 ratio of 4:1? |
|
Definition
| liotrix (Euthyroid, Thyroloar) |
|
|
Term
autoimmune disorder leading to synthesis of antibodies to thyroidal antigens
diffuse toxic goiter; exophthlamic goiter |
|
Definition
|
|
Term
| antibody present in Grave's disease |
|
Definition
thyroid-stimulating immunoglobulin
binds to and activates TSH receptors leading to overactivity and hypertrophy of the thyroid |
|
|
Term
| lab findings of hyperthyroidism |
|
Definition
-high circulating levels of bound and free T3 and T4
-low TSH levels
-anti-thyroid antibodies present |
|
|
Term
| goal of anti-thyroid therapy |
|
Definition
| euthyroid state (normal T3, T4) |
|
|
Term
| How do you treat mild hyperthyroidism in children, pregnant women, and young adults? |
|
Definition
|
|
Term
| Radioactive iodine is preferred treatment of hyperthyroidism in patients... |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| propylthiouracil (PTU, Propyl-thiocil) |
|
|
Term
| What anti-thyroid drug is longer acting and 10 times more potent than PTU? |
|
Definition
|
|
Term
|
Definition
inhibits peroxidase and blocks synthesis of T3 and T4
blocks peripheral conversion of T4 to T3
does not block release of stored hormone (2 days-2 weeks required to deplete stored pool of hormone) |
|
|
Term
| Thioamides are ________ and __________ absorbed. |
|
Definition
|
|
Term
| Thioamides are concentrated by the ________. |
|
Definition
|
|
Term
| Why is a longer dosing interval possible with thioamides even though they have a short half life? |
|
Definition
| because they are concentrated by the thyroid |
|
|
Term
| preferred treatment for pregnant women with hyperthyroidism |
|
Definition
|
|
Term
| preferred treatment for all other patients (besides pregnant women) with hyperthyroidism |
|
Definition
|
|
Term
| Why is methimazole the preferred treatment of hyperthyroidism in all patients except pregnant ones? |
|
Definition
| lower incidence of liver failure than with PTU |
|
|
Term
|
Definition
| severe liver injury and acute liver failure in adults and children |
|
|
Term
| What limits the effectiveness of thioamide therapy? |
|
Definition
|
|
Term
| adverse reactions of thioamides |
|
Definition
-rash
-agranulocytosis (watch for sore throat and fever)
-rare liver failure |
|
|
Term
| mechanism of action of iodide salts in the treatment of hyperthyroidism |
|
Definition
inhibit hormone release
block iodine uptake and T3/T4 synthesis
decrease vascularity |
|
|
Term
| iodide salts indications for hyperthyroidism |
|
Definition
acute inhibition during "thyroid storm"
preparation for surgery (decreases vascularity) |
|
|
Term
|
Definition
potassium iodide U.S.P.
Lugol's solution (5% iodine, 10% Kl) |
|
|
Term
| mechanism of action for radioactive iodine in the treatment of hyperthyroidism |
|
Definition
| 131I taken up by gland, deposited in colloid, beta radiation destroys parenchymal cells |
|
|
Term
| clinical uses of radioactive iodine |
|
Definition
| treatment of hyperthyroidism, metastatic cancers, diagnosis |
|
|
Term
| consequences of surgery and radioiodine therapy for hyperthyroidism |
|
Definition
| 80-90% chance of permanent hypothyroidism |
|
|
Term
|
Definition
| sudden acute exacerbation of thyrotoxicosis--life-threatening! |
|
|
Term
| treatment of thyroid storm |
|
Definition
propranolol (diltiazem)--CV effects
hydrocortisone--protect against shock
supportive therapy
KI--retard release of T3 and T4
PTU--block T3 and T4 synthesis |
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