1
Q
- An elderly woman has been taking digoxin (Lanoxin) for 10 years. Her EKG is
showing a new onset of atrial fibrillation. Her pulse is 64 beats/min. She denies
syncope and dizziness. Which of the following interventions is most appropriate?
A) Order an electrolyte panel and a digoxin level
B) Order a serum thyroid-stimulating hormone (TSH), digoxin level, and an
electrolyte panel
C) Order a serum digoxin level and decrease her digoxin dose by half while waiting
for results
D) Discontinue the digoxin and order another 12-lead EKG
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A
- B) Order a serum thyroid-stimulating hormone (TSH), digoxin level, and an
electrolyte panel Obtaining baseline blood work to evaluate for causes of new-onset
atrial fibrillation is recommended before decreasing or stopping medications.
Thyroid disease is a common cause of new-onset atrial fibrillation.
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2
Q
242. Which of the following groups has been recommended to be screened for thyroid disease? A) Women aged 50 years or older B) Adolescent girls C) Elderly men D) School-aged children
A
- A) Women aged 50 years or older Women have a greater risk of developing
thyroid disease than men. Being age 50 or older increases the risk of thyroid disease
for both men and women. Screening for thyroid disease is therefore recommended
for women 50 years of age and older.
3
Q
251. Which of the following findings is associated with thyroid hypofunction? A) Graves’ disease B) Eye disorder C) Thyroid storm D) Myxedema
A
- D) Myxedema Myxedema (or myxedema) is seen in patients with severe
hypothyroidism. It refers to the skin changes (thickened skin) seen in chronic severe
hypothyroidism. Myxedema coma is a medical emergency with mortality rates
exceeding 20%. It is treated with very high doses of thyroid hormone. A thyroid
storm occurs when there is extreme elevation of thyroid hormones. Thyroid storm is
life-threatening; untreated, the mortality rate is about 90%. Call 911 if suspected.
4
Q
- Which of the following is used to confirm a diagnosis of Hashimoto’s thyroiditis?
A) Serum thyroid-stimulating hormone (TSH)
B) Free T4 test
C) Anti-thyroid peroxidase and anti-thyroglobulin antibodies
D) Thyroid ultrasound
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A
- C) Anti-thyroid peroxidase and anti-thyroglobulin antibodies These are the
two types of antibodies that are positive in Hashimoto’s thyroiditis. Anti-thyroid
peroxidase antibody is also known as antimicrosomal antibody. Hashimoto’s
thyroiditis is the most common cause of hypothyroidism in the United States. The
serum TSH and free T4 test are tests for hypothyroidism, but they are not specific
for Hashimoto’s thyroiditis, an autoimmune disease.
5
Q
260. The best screening test for both hyperthyroidism and hypothyroidism is: A) Free T4 (thyroxine) B) Thyroid-stimulating hormone (TSH) C) Thyroid profile D) Palpation of the thyroid gland
A
- B) Thyroid-stimulating hormone (TSH) The best screening test for both hypothyroidism and hyperthyroidism is TSH level.
A normal TSH rules out primary
hypothyroidism in asymptomatic patients. Abnormal TSH should be followed by determination of thyroid hormone levels.
Overt hypothyroidism is defined as a clinical syndrome of hypothyroidism associated with elevated TSH and decreased serum levels of T4 or T3.
Subclinical hypothyroidism is defined as a condition without typical symptoms of hypothyroidism, elevated TSH (>5 μU/mL), and normal circulating thyroid hormone.
Overt thyrotoxicosis is defined as the syndrome of
hyperthyroidism associated with suppressed TSH and elevated serum levels T4 or T3.
Subclinical thyrotoxicosis is devoid of symptoms, but TSH is suppressed, although there are normal circulating levels of thyroid hormone.
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6
Q
- A new patient who is a 40-year-old female postal worker is being evaluated for
complaints of a new-onset erythematous rash on both cheeks and the bridge of
the nose, accompanied by fatigue. She reports a history of Hashimoto’s thyroiditis
and is currently being treated with Synthroid 1.25 mg daily. Which of the following
conditions is most likely?
A) Atopic dermatitis
B) Thyroid disease
C) Lupus erythematosus
D) Rosacea
A
- C) Lupus erythematosus Classic symptoms of lupus erythematosus are butterfly
rash across both cheeks and the bridge of the nose, and fatigue. Risk factors also include being female and 40 years old. Rosacea also has a similar rash but usually not
associated with fatigue.
7
Q
- The nurse practitioner is evaluating a middle-aged woman who has experienced
gradual weight gain, lack of energy, dry hair, and an irregular period for the past 8
months. Routine annual laboratory testing showed a thyroid-stimulating hormone
(TSH) level of 10 mU/L. The nurse practitioner decides to order a thyroid profile.
Results show that TSH is 8.50 mU/L and serum free T4 is decreased. During the
physical exam, the patient’s body mass index (BMI) is 28. The heart and lung exams
are both normal. Which of the following is the best treatment plan for this patient?
A) Advise the patient that the decreased thyroid-stimulating hormone (TSH) level
means her thyroid problem has resolved
B) Start the patient on levothyroxine (Synthroid) 0.25 mcg PO daily
C) Start the patient on Armour thyroid
D) Refer the patient to an endocrinologist
A
- B) Start the patient on levothyroxine (Synthroid) 0.25 mcg PO daily The
patient is symptomatic (weight gain, lack of energy, and irregular periods) with low
free T4. Even though the thyroid-stimulating hormone (TSH) level decreased
slightly, the free T4 remains low. An elevated TSH and low free T4 are indicative of
hypothyroidism. The next step is to start the patient on levothyroxine (Synthroid)
0.25 mcg daily and recheck the TSH in 6 weeks. The goal is to normalize the TSH
(between 1.0 and 3.5) and to ameliorate the patient’s symptoms (increased energy,
feels better, etc.). Armour thyroid (desiccated thyroid) is a natural supplement
composed of dried (desiccated) pork thyroid glands. It is used in alternative medicine
as an alternative to synthetic levothyroxine/T4 (Synthroid).
8
Q
- A 35-year-old woman is complaining of gradual weight gain, lack of energy, and
amenorrhea. The urine pregnancy test is negative. A complete blood count (CBC)
shows hemoglobin of 13.5 g/dL and mean corpuscular volume (MCV) of 84 fL. The
nurse practitioner suspects that the patient may have hypothyroidism. The thyroidstimulating
hormone (TSH) level is 10 mU/L. Which of the following is the next
step in the evaluation?
A) Check the thyroid profile
B) Check the total T3 level
C) Check the FSH level
D) Recheck the TSH in 4 to 6 months
A
- A) Check the thyroid profile The upper limit of the serum thyroid-stimulating
hormone (TSH) level is about 4.0 mU/L. With an elevated TSH of 10, it is
important to rule out hypothyroidism. The next step in this patient’s evaluation is to
order a thyroid profile or thyroid panel test. Serum assays measure bound and
unbound (free) forms of thyroxine (T4) and triiodothyronine (T3). Classic findings
of hypothyroidism are a low free T4, low T3-resin uptake (THBI), and low free T4
index.
9
Q
- A 28-year-old woman with a history of hypothyroidism presents to an urgent
care clinic complaining of numbness and tingling in the fingertips of both her
hands for several hours. On examination, both radial pulses are at +2 and equal
bilaterally. The patient reports that over the past few months she has had identical
episodes, each lasting several hours. During these episodes, the skin changes color
from blue to white, and then to dark red. Eventually, it returns to normal and the
tingling and numbness disappear. Which of the following conditions is best
described?
A) Hashimoto’s disease
B) Raynaud’s phenomenon
C) Peripheral neuropathy
D) Vitamin B12 deficiency anemia
A
- B) Raynaud’s phenomenon Raynaud’s phenomenon involves an interruption in
the blood flow to fingers and toes (sometimes nose and ears), due to spasms in the
blood vessels. During a Raynaud’s attack, the affected area typically turns white, and,
as oxygen fails to reach the extremities, they can turn blue, tingle, or throb painfully,
and the affected area may swell. Symptoms may resolve quickly or last for hours.
Raynaud’s disease is more common in women, is not curable, and it is associated
with increased risk of other autoimmune diseases such as rheumatoid arthritis or
lupus, but treatment can decrease symptoms. The preferred drug is a calcium
channel blocker such as nifedipine (Norvasc) or amlodipine (Procardia).
10
Q
23. Epidemiological studies show that Hashimoto’s disease occurs most commonly in: A) Middle-aged to older women B) Smokers C) Obese individuals D) Older men
A
- A) Middle-aged to older women Hashimoto’s disease (Hashimoto’s thyroiditis,
or chronic lymphocytic thyroiditis) is an autoimmune disease. An enlarged thyroid is
most often the first sign of the disease. Hashimoto’s disease is about seven times more
common in women than in men. It can occur in teens and young women, but is
more common in middle age.
