Thyroid Disorders Flashcards

Question

Attaining Remission

Answer 1

Continue x 12-18 months Then taper or d/c if euthyroid at that time 20-30% of patient achieve remission after initial therapy Remission: normal TSH, FT4, and T3 one year after d/c of antithyroid medication Follow-up Re-test every 1-3 months for 6-12 months after initial remission and d/c of methimazole Failure to maintain remission Radioactive iodine or thyroidectomy

Answer 2

GI upset Arthralgia Rash, urticaria, pruritis 5-6% of patients Severe reactions: treat with 1 mg/kg/day prednisone and d/c therapy Mild: symptoms likely to resolve on own

Answer 3

``` Severe Adverse Effect of Thioamides More likely in First 2 months Higher doses Age >40 yo 0.2-0.5% incidence Granulocyte count <250/mm3 Fever, sore throat, bleeding , bruising, malaise, stomatitis Stop drug, administer broad spectrum antibiotics ```

Answer 4

``` Higher risk with PTU FDA safety alert Treatment d/c therapy Gradually resolves on own Long term therapy: monitor LFTs ```

Answer 5

Free T4 levels 4 months after starting therapy Every 4-8 weeks until normalized, then every 2-3 months WBC Onset of febrile illness or pharyngitis LFTs Patients on PTU with signs of liver damage: jaundice, joint pain, abdominal pain, light stool, dark urine, GI upset or fatigue

Answer 6

``` Inhibits thyroid hormone release Decrease thyroid hormone synthesis Decrease thyroid gland vascularity Initial effect within 24 hours, max in 10-15 days of continuing therapy Improvement in symptoms in 2-7 days ```

Answer 7

Reduce vascularity prior to thyroid surgery Prepare patients with Graves Disease for surgery Decrease thyroid iodine accumulation in thyrotoxic crisis Prevent thyroid uptake of radioactive iodine

Answer 8

Saturated solution (SSKI) 50mg of iodide per drop Lugol’s solution 8 mg of iodide per drop

Answer 9

50-500 mg orally in water or juice To prepare for surgery: administer 10-14 days preoperatively As adjunct to RAI, use 3 to 7 days after RAI treatment Radioactive iodine will concentrate in the thyroid

Answer 10

``` Rash GI upset Paresthesia Immune hypersensitivity reactions Salivary gland swelling Iodism Burning in mouth or throat Metallic taste Sore teeth and gums Cold symptoms ```

Answer 11

Not recommended in ATA/AACE guidelines Adverse effects Tremor, polyuria, renal failure, seizure, arrhythmia, bradycardia, suicide, toxicity

Answer 12

1. Symptomatic treatment of palpitations, tachycardia, tremor, heat intolerance 2. Thyrotoxicosis 3. Recommended for symptomatic elderly, postpartum women, children, any patient with resting HR> 90 or CVD 4. Preoperatively adjunct to potassium iodide, radioactive iodine or antithyroid drugs for Graves’ disease or toxic nodules 5. Thyroid storm 6. Monotherapy for thyroiditis

Answer 13

Blocks beta adrenergic receptors to mitigate adrenergic symptoms of thyrotoxicosis Propranolol and nadolol may decrease conversion of T4 to T3

Answer 14

``` Propranolol 10-40 mg po 3-4x daily Nadolol 40-60 mg po 1x daily Atenolol 25-100 mg po 1-2x daily Metoprolol tartrate 25-50mg po 4x daily Esmolol 50-100 mcg/kg/min IV in ICU for thyroid storm ```

Answer 15

Sodium iodide 131 aka 131I Oral solution MOA Disrupts hormone synthesis by incorporating into thyroid hormone and thyroglobulin Over a period of weeks, follicles develop evidence of necrosis, breakdown, destruction of small vessels within gland Half life- 5 days

Answer 16

Contraindicated Pregnancy: test 48 hours prior to procedure Lactation Thyroid cancer

Answer 17

Ablation for Graves disease Women planning pregnancy greater than 4-6 months in the future Patients with increased surgical risk or prior neck surgery Contraindication to antithyroid medication Benefits: Well tolerated Low risk of thyroid storm

Answer 18

T3 and T4 1-2 months after treatment Hypothyroidism occurs 4 weeks after treatment Retreat x 1 if minimal response after 3 months or persistent hyperthyroidism after 6 months T4 replacement 50% of patients require in 10 years

Answer 19

Dysphagia | Thyroid tenderness

Answer 20

Stress from surgery, anesthesia, thyroid manipulation in patients with undiagnosed or uncontrolled thyrotoxicosis Abrupt d/c of antithyroid medication

Answer 21

Thyrotoxic crisis Life threatening 20-30% mortality

Answer 22

``` High fever (often >103*F) Tachycardia Atrial fibrillation Congestive heart failure Tachypnea Dehydration Delirium Coma Nausea/vomiting/ diarrhea ```

Answer 23

``` Aggressive treatment recommended Identify and treat cause Antithyroid medications Give BEFORE iodide Inorganic iodide Supportive care Fluids, cooling blankets, acetaminophen Beta blockade Corticosteroid therapy ```

Answer 24

*Hydrocortisone - 300 mg loading dose IV Then 100 mg Q8hours PTU- 500-1000 mg loading dose Then 250 mg Q4 hours SSKI- 5 drops (0.25 mL or 250 mg) Q6hours Methimazole- 60-80 mg/day Beta blocker ``` BETA BLOCKERS Propranolol 60-80 mg po Q4 hours Blocks T4 to T3 conversion Esmolol infusion In heart failure or when po not plausible CORTICOSTEROIDS Dexamethasone is an alternative Blood pressure stabilization ```

Answer 25

``` Diagnosis Low TSH Thyroid hormone level within normal limits Clinical Concern Atrial fibrillation (especially in elderly) Cause Amiodarone induced Treatment Initiate with TSH < 0.1mIU/L ```

Answer 26

``` MC= Hashimoto’s thyroiditis Autoimmune disease Genetic predisposition Iatrogenic Drugs Radiation Surgery Other: endemic iodine deficiency, congenital ```

Answer 27

Pituitary disease | Hypothalamic disease

Answer 28

``` Amiodarone Sunitinib Lithium Interferon Thalidomide Bexarotene Ethionamide Rifampicin Anti thyroid medications : PTU, methimazole ```

Answer 29

Subclinical hypothyroidism TSH above normal levels, thyroid hormone within normal limits Treat with TSH > 10 mIU/L Myxedema Associated with coronary artery disease Treat with caution to avoid precipitating a cardiac event Myxedema coma End result of untreated hypothyroidism Medical emergency Requires ICU, intubation, IV levothyroxine loading dose

Answer 30

``` Dry skin Cold intolerance Weight gain Constipation Weakness Lethargy Depression Fatigue/loss of ambition & energy ```

Answer 31

``` Coarse skin and hair Cold or dry skin Periorbital puffiness Bradycardia Slow, hoarse speech ```

Answer 32

↑ TSH, ↓ Free thyroxine (FT4)

Answer 33

+ Antithyroglobulin antibody (ATgA) + Thyroid peroxidase antibody (TPOS ab) [aka antimicrosomal antibody (AMA)] + blocking TSH receptor antibody (TSH-R block) ↑ Cholesterol, LDH, AST, ALT, CPK

Answer 34

``` Natural Desiccated thyroid and thyroglobulin Synthetic Levothyroxine Liothyronine Liotrix ```

Answer 35

ATA/ AACE Guidelines Initiate treatment TSH > 10 mIU/L TSH= 4.5-10 mIU/L- No Consensus Synthetic L-thyroxine is recommended first line Consistent use of one formulation/manufacturer If changed, test TSH in 4-6 weeks Less data to support desiccated thyroid

Answer 36

Desiccated thyroid | Compounded from hog, beef or sheep thyroid gland

Answer 37

First line, synthetic L-thyroxine (T4) Brand and branded generic available Synthroid, Levoxyl

Answer 38

``` Absorption 40-80% bioavailable Increases with fasting Decreases with fiber Distribution 99% protein bound TBG Thyroxine binding prealbumin (TBPA) Metabolism 80% hepatic: Active metabolite Renal: Deiodination Enterohepatic recirculation Excretion Renal (80%) Fecal (20%) Half life: 6-7 days ```

Answer 39

Oral 30 minutes prior to breakfast 4 hours after last meal at bedtime Intravenous recommend 50% of oral dose Feeding tube Crush tablet and create suspension with water Wait at least 1 hour to restart feeding Administer as long as possible after stopping feeding

Answer 40

Chemically pure with known potency Synthetic T3 Half life: 1.5 days Disadvantages Higher incidence of cardiac effects Higher cost Difficult to monitor with conventional lab tests

Answer 41

``` Synthetic T4:T3 Ratio is 4:1 Attempt to mimic natural hormone secretion Chemically stable and pure Predictable potency Disadvantages High cost Lack of therapeutic rationale ```

Answer 42

Dependent on age, sex, weight Ideal body weight is recommended Initial dosing 1.6-1.7 mcg/kg/day (full replacement dose) Requirement may be lower in patients with residual thyroid function Elderly or CAD: 25-50 mcg/day Consider lower doses: long standing disease, severe disease, iron deficiency anemia Adjust every 4-8 weeks based on TSH 12.5-25 mcg/day increments

Answer 43

Euthyroid essential for normal neurocognitive development in fetus Women being treated for hypothyroidism ↑ rate of metabolism for thyroid hormone/ transplacental transport Dose of levothyroxine should be increased by 30% Thyroid function tests should be tested every 2-3 weeks TSH goal depends on trimester: 2.5 mIU/L, 3 mIU/L and 3.5 mIU/L (1st, 2nd, 3rd trimester respectively)

Answer 44

``` Allergic ReactionsArrhythmia Acute myocardial infarction Infertility Weight loss Heat intolerance ```

Answer 45

TSH and T4 should be measured every 4-8 weeks until euthyroid Normal TSH: 0.4-4mIU/L Normal FT4: 0.8-1.5ng/dL Once normalized, should measure TSH and free T4 once every 6-12 months

Thyroid Disorders Flashcards

(69 cards)