Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Thyroid disorders in everyday care Chris Vreeland, RN, MSN, NP-c Georgia Mountain Endocrinology, PC Introduction • One in ten Americans have a thyroid disorder • Body’s response to thyroid disorders is fatigue - most common reason to seek healthcare. • Women particularly affected by thyroid imbalance Weight Fertility Pregnancy Menopause Osteoporosis Thyroid Hormone Action • Activates nuclear receptors which regulate expression of thyroid hormone-responsive genes: Fetus & neonate: differentiation of target tissues Childhood: differentiation/proliferation Adolescent: role in action of sex steroids Thyroid Hormone Action • Gene expression (continued) All ages: • Regulates energy production • Regulates functional /structural proteins • Regulates action of other hormones - glucocorticoids, mineralocorticoids, growth factors, biologic amines (catecholamines) Negative Feedback Loop • Thyroid hormone inhibits pituitary secretion of TSH • Hypothalamus plays crucial role • TSH very sensitive indication index of action • TSH & thyroid hormones maintained in a certain relationship • Modified by TBG (thyroxine-binding globulin) Negative Feedback Loop Hyperthyroidism • Elevated serum thyroid level • Decreased TSH Hypothyroidism • Decreased serum thyroid levels • Increased TSH Serum Levels of Thyroid Hormones • T3 regulates peripheral action of hormone • T3 & T4 both released from gland • Peripheral conversion of T4 to T3 occurs in liver and target tissues • In presence of liver damage, T3 conversion may be low despite good levels of T4 TBG Metabolism • T4 transported to tissue by TBG • High serum TBG (liver damage, pregnancy, OCP’s, HRT) lowers serum concentrations of free T4 which decreases amount of substrate (T4) that can be converted to T3 • Indirect measure of TBG abnormality is T3 uptake Causes of Thyroid Disorders Hyperthyroidism • Graves’ disease: • Autoimmune • TSH receptor antibodies • Thyroiditis: • Sub-acute • Post-partum • Pituitary tumor - TSH producing Causes of Thyroid Disorders Hypothyroidism (High TSH, low T3, T4) • Hashimoto thyroiditis: • Autoimmune TPO and thyroglobulin antibodies • RAI: radioactive iodine ablation • Surgery • Antithyroid drugs • Goitrogens: lithium, amiodarone Normal Hormone Levels • TSH: 0.4-5.5 MIU/L • Total T3: 60-181 NG/DL • Total T4: 4.5-12.5 MCG/DL • T3 Uptake: 22-35% Hypothyroidism Symptoms Fatigue Weight gain Cold feeling Dry hair, nails, skin Hair loss Heavier or longer menses Constipation Peripheral edema Periorbital edema Bradycardia Hypotension Infertility Hypothyroidism • Treatment: • Hormone replacement (L-T4) Absorbed from small intestine 6-day half-life • Daily dosing: 0.025-.300 mgs • Branded preparations preferred to generic Synthroid Levoxyl Tirosint Hypothyroidism • Treatment Initial dose: 1.7 mcg per kg Pregnant: may need 1.8 mcg per kg Elderly: usually start at lower doses, esp. with angina or CAD • Monitoring 6-8 weeks after any dose change Annually once stable Each trimester in pregnancy Hypothyroidism • Myxedema Coma End stage of uncompensated hypothyroidism Presents most often in elderly and women in winter months Present in respiratory failure, hypotension, bradyarrythmia, along with serious precipitating illness Treatment is T4 IV @ 1/10th dose of oral ICU admit for multi-system failure Hypothyroidism Pearls Most patients reports feeling best with TSH between 1-2 If TSH normal, but patient still not feeling good, think low T3; may need Cytomel (oral T3) Depression very common Inadequate treatment can contribute to infertility Look for recent onset of symptom with family history of thyroid disease Hyperthyroidism Symptoms Anxiety Palpitations Unintended weight loss Decreased or absent menses Oily skin Fine, silky, oily-appearing hair Heat intolerance Exopthalmos (not all cases) Tachycardia Hyperthyroidism Treatment • Anti-thyroid drugs Methimazole Inhibits thyroid hormone synthesis in the thyroid gland PTU Inhibits thyroid hormone synthesis in the thyroid gland & inhibits peripheral conversion of T4 to T3 Hyperthyroidism Dosing: • Tapazole: 10 mg BID or TID • PTU: only 50 mg tablets available Usual starting dose: 2 tabs TID; may double dose if necessary • Both very effective at lowering thyroid hormone levels • TSH will stay suppressed several month Hyperthyroidism Dosing: Monitor every 4-6 weeks When TSH rises, may need to add T4 (thyroid hormone) Want to leave on ATD’s long enough to allow TSH receptor antibodies to decrease & induce remission; usually 12-18 months Plan to withdraw med at 12-18 months to evaluate remission status Hyperthyroidism Side effects of anti-thyroid drugs: • Leucocytopenia • Agranulocytosis-most serious • Pernicious anemia • Thrombocytopenia • Hepatic dysfunction • Allergy (discoid rashes) Evaluate with CMP, CBC, & thyroid hormone levels every 4-6 months Hyperthyroidism Radioactive Iodine Ablation • Administration of I131 iodine by mouth • Used after TFT’s normal or if unable to control hyperthyroidism with drugs • Usually destroys gland over 3-6 months Hyperthyroidism Radioactive Iodine Ablation • Induces permanent hypothyroidism • May cause post-treatment thyroid storm (rare) • May cause aggravation of Graves’ eye disease • Pregnancy should be prevented within 6 months after treatment Hyperthyroidism Surgery • When disease state or gland size can’t be controlled with drugs • When gland causing obstructive signs Difficulty breathing either supine or upright -Evaluated by PA & LAT CXR Difficulty swallowing food -Evaluated by barium swallow Hyperthyroidism • Thyroid Storm • Most often with Graves’ disease • Levels same as with Graves’ • Cardinal signs: Temperature 102 to 1050 Profuse sweating Marked tachycardia (120-140 pulse rate or higher) Atrial fibrillation • Usually induced by concurrent infection or surgery on hyperactive gland Hyperthyroidism Thyroid storm • Treatment PTU orally or by NG tube Tapazole not favored because it does not inhibit peripheral conversion of T4 to T3 Beta blockade, PO or IV Supportive therapy for fever, dehydration Perhaps iodine solution or corticosteroids Hyperthyroidism Graves’ Eye Disease: • Caused by antibody effect on orbital tissue • Symptoms include: Edema Inflammation Hypertrophy of extra ocular muscles & orbital fat • Exopthalmos upper & lower lid retraction, strabismus, herniated orbital fat Hyperthyroidism Graves’ Eye Disease: • Should be stabilized for 6 months prior to any other treatment modality • Exception is optic neuropathy caused by strangulation of optic nerve • Extent of protrusion measured by increase in distance between lateral orbital rim and anterior aspect of eye Thyroid Nodules • May be a single nodule or larger of multiple nodules • 95% benign • More common in women • More likely malignant in men • Increase in size while on T4 therapy worrisome for malignancy Thyroid Nodules • Note size, consistency and mobility on physical exam • Evaluate for tracheal deviation or esophageal obstruction • Usually TSH suppressed, T3 and T4 levels normal • Antibodies may be present, but more likely they are not not • Ultrasound best way to diagnose Thyroid Nodules Treatment • Multinodular gland without dominant nodule: T4 to shrink if TSH not suppressed • Single nodule 1 cm or greater: fine needle aspiration biopsy • Enlarging nodule despite “good” dose of T4 or indeterminate or malignant result from FNA indicates need for surgery Thyroiditis • Most common cause: chronic autoimmune thyroiditis or postpartum thyroiditis • Next is sub acute thyroiditis • More rare: acute suppurative thyroiditis Thyroiditis Post-partum thyroiditis • May occur anytime in the first year, but most common in first 3 months • Usually have hyperthyroid symptoms first, followed by hypothyroid findings • Gland usually enlarged • Will not have other markers for inflammation: fever, tenderness, high sed rate Thyroiditis Post-partum thyroiditis • Usually spontaneously resolve • May need temporary medication support for symptoms Beta blockers for tachycardia Tranquilizers for anxiety T4 for hypothyroidism • Can progress to permanent hypothyroidism Thyroiditis Sub acute • Usually follows viral illness • Gland is swollen, tender • Sed rate elevated >50mm/hour • May have fever, even fairly mild • Leucocytosis • Follows usual pattern of transient hyperthyroidism, then hypothyroidism, then euthyroid Thyroiditis Sub acute • Treatment: Symptomatic NSAIDS for pain, fever Prednisone for severe pain unrelieved by above Beta blockers for hyper phase Thyroid replacement for hypo phase Resolve spontaneously Questions? Thank you!