Thyroid disorder Flashcards by Williams Adeyemi

What is the most common cause of hypothyroidism in North America?

Hashimoto thyroiditis

Anti-TPO levels could be elevated in this condition.

How well did you know this?

Not at all

Perfectly

What is the normal range for TSH levels?

0.3–4 mU/L

TSH levels above this range may indicate hypothyroidism.

How well did you know this?

Not at all

Perfectly

What is subclinical hypothyroidism defined by?

Elevated TSH with normal thyroid hormone levels

Treatment should be considered if TSH >10 mU/L.

How well did you know this?

Not at all

Perfectly

List some common signs and symptoms of hypothyroidism.

Fatigue
Impaired memory
Constipation
Cold intolerance
Changes in skin or hair

These symptoms are often nonspecific.

How well did you know this?

Not at all

Perfectly

What laboratory investigation is sufficient when screening for primary hypothyroidism?

TSH alone

Additional tests may be required if TSH is abnormal.

How well did you know this?

Not at all

Perfectly

What is the treatment of choice for hypothyroidism?

Levothyroxine (L-T4)

The goal is to normalize the TSH level.

How well did you know this?

Not at all

Perfectly

What is the average replacement dosage of levothyroxine for adults?

1.6 mcg/kg/day

Dosage adjustments are made every 6 weeks as needed.

How well did you know this?

Not at all

Perfectly

True or false: Liothyronine (T3) is ideal for long-term replacement therapy.

FALSE

T3 cannot replace the stability provided by the long half-life of L-T4.

How well did you know this?

Not at all

Perfectly

What should be monitored in patients with hypothyroidism during pregnancy?

TSH levels

TSH should be measured every 6 weeks or 4 weeks after dosage adjustment.

How well did you know this?

Not at all

Perfectly

What is the recommended action for patients on thyroid hormone replacement after a positive pregnancy test?

Increase levothyroxine dose by 2 extra tablets per week

Further adjustments should be based on TSH levels.

How well did you know this?

Not at all

Perfectly

What is myxedema coma?

A medical emergency associated with severe hypothyroidism

Symptoms include hypotension and decreased level of consciousness.

How well did you know this?

Not at all

Perfectly

What defines thyrotoxicosis?

Excessive thyroid hormone and its effects

Hyperthyroidism is a specific cause of thyrotoxicosis.

How well did you know this?

Not at all

Perfectly

What is the most common cause of hyperthyroidism?

Graves disease

Patients frequently have eye disease and possibly pretibial myxedema.

How well did you know this?

Not at all

Perfectly

What is subclinical hyperthyroidism characterized by?

Suppressed TSH with normal thyroid hormone levels

Treatment is indicated in older or frail patients with risk factors.

How well did you know this?

Not at all

Perfectly

What is the treatment for thyroid storm?

Levothyroxine 300–500 mcg IV initially, followed by 100 mcg IV daily

Corticosteroids such as hydrocortisone may also be used.

How well did you know this?

Not at all

Perfectly

What should be avoided in patients with Graves disease during surgery?

Hypothyroidism

Medical therapy with antithyroid drugs is often initiated prior to surgery.

How well did you know this?

Not at all

Perfectly

What is the role of radioactive iodine (131I) in hyperthyroidism?

Ablate thyroid tissue

Used in patients with Graves disease and toxic multinodular goiter.

How well did you know this?

Not at all

Perfectly

What is the surgery part of the management for?

Thyroid cancer and ectopic production of thyroid hormone

Surgery is critical in managing these conditions, and medical therapy with antithyroid drugs is often initiated prior to surgery.

How well did you know this?

Not at all

Perfectly

What is a common side effect of surgery for thyroid conditions?

Hypothyroidism

Follow closely postoperatively to determine when thyroid replacement is required.

How well did you know this?

Not at all

Perfectly

What is the purpose of radioactive iodine (131I) in thyroid treatment?

Ablate thyroid tissue

It is used in patients with Graves disease, toxic autonomous nodules, and toxic multinodular goitres.

How well did you know this?

Not at all

Perfectly

What is a major risk associated with the use of radioactive iodine (131I)?

Study These Flashcards

Inducing hypothyroidism

It is contraindicated in pregnancy.

What are the two antithyroid drugs mentioned?

Study These Flashcards

Methimazole
Propylthiouracil

Both decrease the production of thyroid hormones.

What should be done about antithyroid drugs before a thyroid scan?

Study These Flashcards

Stop about 5 days prior

This includes scintigraphy, 131I uptake, or treatment with 131I.

What are the side effects of antithyroid agents?

Study These Flashcards

Allergy
Rash
Agranulocytosis
Hepatotoxicity
Nephrotoxicity

Methimazole is preferred due to a lower incidence of serious hepatotoxicity.

What is the role of **beta-blockers** in thyroid management?

Ameliorate symptoms of adrenergic excess ## Footnote They are usually used adjunctively in the management of Graves disease or toxic nodules.

What does **iodine** do in the management of hyperthyroidism?

Blocks thyroid hormone production ## Footnote It can be used in the acute management of severe hyperthyroidism.

What is the management approach for **thyroid storm**?

* Supportive therapy * Aggressive treatment with antithyroid medications * Beta-blockers * Corticosteroids ## Footnote Patients with thyroid storm are best managed in a critical care setting.

True or false: **Hyperthyroidism** during pregnancy is well tolerated.

TRUE ## Footnote However, it should be treated to target fT3 and fT4 levels near the upper limits of normal.

What should patients with **Graves disease** do before conception?

Ensure thyroid levels are well controlled ## Footnote Consult with a physician if treated with radioactive iodine or surgery.

What is the preferred antithyroid drug during the **first trimester** of pregnancy?

Propylthiouracil ## Footnote Methimazole is associated with a higher risk of congenital abnormalities.

What should be monitored during pregnancy for patients with hyperthyroidism?

TSH, fT3, and fT4 every 6–8 weeks ## Footnote More often if there is a change in clinical status or dose.

What is the risk of untreated **hyperthyroidism** during pregnancy?

Increased risk of fetal loss ## Footnote Patients should be aware of the potential impact on the fetus.

What should be done if a patient is on **high doses** of antithyroid medication during breastfeeding?

Check the baby’s TSH level ## Footnote This ensures the baby is not made hypothyroid.

What is the **goal** of managing hyperthyroidism during breastfeeding?

Ensure fT3 and fT4 levels are near the upper limit of normal ## Footnote Avoid overtreatment to prevent adverse effects.

What should patients be reminded of regarding **Graves disease** postpartum?

Symptoms of hyperthyroidism may reactivate ## Footnote Patients should have their thyroid levels checked if they suspect a problem.

What are the **risks** of untreated hyperthyroidism?

* Thyroid storm * Myopathy * Cardiac arrhythmias * Cardiomyopathy * Osteoporosis ## Footnote Patients should be warned about these risks.

What should be done for patients with **goitre**?

Screen with a TSH level ## Footnote Goitres in euthyroid patients can be problematic if growing or causing compressive symptoms.

What is the usual treatment for **compressive symptoms** of thyroid enlargement?

Surgery ## Footnote Surgical pathology will confirm or exclude malignancy.

What are the **risk factors for thyroid cancer**?

* Age <20 or >60 * Nodule fixed to soft tissue * Family history of thyroid cancer * Previous malignancy * Lymphadenopathy * Prior radiation exposure * Male * Vocal cord paralysis * Nodule >4 cm or rapidly growing ## Footnote These factors increase the risk for malignancy.

What is the **preferred antithyroid drug** during breastfeeding?

Methimazole ## Footnote It is preferred due to concerns of serious hepatotoxicity associated with propylthiouracil.

What is the recommended monitoring frequency for **TSH levels** after adjusting dosage?

* After 6–8 weeks * At least annually * Sooner if new symptoms suggest a dose adjustment ## Footnote Adrenal insufficiency may be uncovered; dosage usually needs to be increased during pregnancy.

What is the **initial dosage** of **liothyronine (T3)** for short-term management in patients with thyroid cancer?

Up to 25 mcg BID PO ## Footnote This is after stopping levothyroxine.

List the **adverse effects** of **liothyronine (T3)** if overtreated.

* Symptoms of hyperthyroidism * Possible exacerbation of angina ## Footnote Absorption may be reduced by antacids, calcium salts, and other medications.

True or false: **T3** crosses the placenta and can be used alone as replacement in pregnancy.

FALSE ## Footnote T3 should not be used alone as replacement in pregnancy.

What is the **preferred first-line agent** for hyperthyroidism in children?

methimazole (MMI) ## Footnote Except during the first trimester of pregnancy when PTU is preferred.

What are the **dosage recommendations** for **propylthiouracil (PTU)** in thyroid storm?

Up to 1200 mg daily in divided doses ## Footnote Initial dose is 50–100 mg TID PO in most cases.

What are the **adverse effects** of **propranolol**?

* Bradycardia * Dizziness * Fatigue * Headache * Hypotension ## Footnote Avoid in patients with asthma or conditions associated with bradycardia.

What is the **initial dose** of **atenolol** for hyperthyroidism?

25–50 mg daily PO ## Footnote May increase to 200 mg daily.

What is the **dosage for dexamethasone** in thyroid storm?

2 mg Q6H PO or IV ## Footnote Continue until free T3 level controlled.

What is the **dosage of Lugol solution** for thyroid storm?

3–5 drops Q6H PO, 1 h after antithyroid drug ## Footnote Administer 1 h after PTU or MMI.

What is the **risk** associated with **sodium iodide 131I** treatment?

* High risk of hypothyroidism * Possible worsening of Graves orbitopathy * Risk of radiation thyroiditis ## Footnote Given as a single oral dose; usually only 1 dose required.

Thyroid disorder Flashcards

(51 cards)