Chemistry 4.1

Question 1

A 35-year-old pregnant female has the following laboratory results. What is the most likely explanation for these results?
TSH
T4
FT4
T3
3.4 mIU/L (0.3-4.2)
5.4 mU/L (0.4-4.0)
1.5 ng/dL (0.9-1.7)
220 ng/dL (80-200)
F13 3.3 pg/mL (2.8-4.4)
A) Secondary hyperthyroidism
B) Subclinical hypothyroidism
C) Primary hyperthyroidism
D) Euthyroidism

Answer 1

D) Euthyroidism

Question 2

The following laboratory results correlate with which of the following thyroid disorders?
TSH
14
FT4
T3
TRH
7.8 mIU/L (0.3-4.2)
0.3 mU/L (0.4-4.0)
0.5 ng/dL (0.9-1.7)
58 ng/dL (80-200)
40 pg/mL (≤ 40)
A) Subclinical hypothyroidism
B) Tertiary hypothyroidism
C) Primary hypothyroidism
D) Secondary hypothyroidism

Answer 2

C) Primary hypothyroidism

Question 3

Which of the following tests may be used to differentiate between hypothalamic hypothyroidism and pituitary hypothyroidism?
A) Thyroid stimulating hormone
B) Free thyroxine index
C) Thyroperoxidase antibody
D) TH stimulation test

Answer 3

D) TH stimulation test

Question 4

Inhibition of thyrotropin releasing hormone is associated with what hormones produced by the delta cells of the islets of Langerhans?
A) Thyroid Stimulating hormone
B) Parathyroid hormone
C) Calcitonin
D) Somatostatin

Answer 4

D) Somatostatin

Question 5

Which of the following thyroid tests should be used to screen a 2-year-old child who presents as dwarfed, stocky, overweight, and having coarse features?

A) Thyroid-stimulating hormone (TSH)
B) Triiodothyronine (Т3)
C) Thyroxine-binding globulin (TBG)
D) Thyroxine (T4)

Answer 5

A) Thyroid-stimulating hormone (TSH)

Question 6

A patient sample is added to a reaction vessel with anti-T monoclonal antibody conjugated to alkaline phosphatase. During incubation, FT3 reacts with anti-T3 antibody. Particles coated with streptavidin and biotinylated T3 analog are added to the reaction vessel. Immune complexes bound to the solid phase are held in a magnetic field, while unbound substances are then removed by a wash step. What is the principle of this FT3 assay?
A) Heterogenous enzyme linked absorbent immunoassay
B) Non-competitive chemiluminescence immunoassay
C) Homogenous microparticle enzyme immunoassay
D) Competitive binding immunoenzymatic assay

Answer 6

C) Homogenous microparticle enzyme immunoassay

Question 7

Primary, secondary, and tertiary disorders correspond to what endocrine glands respectively?
A) Hypothalamus, pituitary, target gland
B) Target gland, hypothalamus, pituitary
C) Pituitary, hypothalamus, target gland
D) Target gland, pituitary, hypothalamus

Answer 7

D) Target gland, pituitary, hypothalamus

Question 8

Quantitatively, what is the major fraction of organic iodine circulating in the bloodstream?
A) Tetraiodothyronine
B) Triiodothyronine
C) Thyroglobulin
D) Diiodotyrosine

Answer 8

A) Tetraiodothyronine

Question 9

What are the expected laboratory results in a patient suspected of having Hashimoto’s disease?
A) Increased T4, increased TSH
B) Decreased 14, increased TSH
C) Increased T4, decreased TSH
D) Decreased T4, decreased TSH

Answer 9

B) Decreased 14, increased TSH

Question 10

What are the expected laboratory results in a patient with suspected primary hyperthyroidism?
A) Increased T3, normal TSH
B) Increased T4, decreased TSH
C) Increased T4, normal TSH
D) Increased T4, increased TSH

Answer 10

B) Increased T4, decreased TSH

Question 11

A patient was scheduled for fasting blood work in the morning and an afternoon appointment with the endocrinologist. The a.m. cortisol was 15.0 g/dL. The endocrinologist ordered a timed cortisol immediately prior to the 4 p.m.
appointment. While reviewing the results, the provider noted that the p.m. cortisol was 7.5 g/dL. What is the most likely explanation for these results?
A) Cushing’s syndrome
B) Addison’s disease
C) Reagent deterioration
D) Diurnal variation

Answer 11

D) Diurnal variation

Question 12

Given the following patient data, what additional test is needed for the endocrinologist to make a definitive diagnosis of medullary thyroid carcinoma?
PTH 49 pg/mL (15.0-65.0)
Calcium 5.2 mg/dL (8.6-10.0)
A) Growth hormone
B) 5-hydroxyindolacetic acid
C) Calcitonin
D) Thyroid stimulating hormone

Answer 12

C) Calcitonin

Question 13

Which of the following hormones decreases blood glucose concentrations by (1) enabling glucose to enter muscle cells, which promotes glucose utilization, and (2) enabling glucose to enter liver cells, which promotes glycogenesis?
A) Cortisol
B) Glucagon
C) Insulin
D) Epinephrine

Answer 13

C) Insulin

Question 14

Which of the following drugs falsely elevates the plasma renin activity and interferes with plasma aldosterone measurements?
A) Selective serotonin reuptake inhibitors
B) Hormone replacement therapy
C) Corticosteroid injections
D) ACE inhibitors

Answer 14

D) ACE inhibitors

Question 15

Which of the following tests should be included in a sepsis bundle as a quality indicator?
A) Procalcitonin
B) Calcitonin
C) Insulin
D) Dehydroepiandrosterone

Answer 15

A) Procalcitonin

Question 16

A 58-year old female was seen by her primary care physician with chief complaints of fatigue, hair loss, dry skin, and cold intolerance. Her laboratory results correlate with which of the following diseases?
TSH 5.9 mlU/L (0.4-4.0)
T4 4.0 g/dL (5.0-10.0)
A) Primary hypothyroidism
B) Primary hyperthyroidism
C) Secondary hyperthyroidism
D) Secondary hypothyroidism

Answer 16

A) Primary hypothyroidism

Question 17

What is the body’s feedback mechanism when there is decreased thyroid hormone production?
A) Stimulation of the thyroid to increase thyroxine iodination
B) Inhibition of the hypothalamus to decrease TRH synthesis
C) Stimulation of the pituitary gland to increase TSH production
D) Inhibition of the thyroid gland to secrete T3 and 14 hormones

Answer 17

C) Stimulation of the pituitary gland to increase TSH production

Question 18

Which of the following statements concerning adrenal cortical hormones is true?
A) Cortisol, a glucocorticoid, is produced by the zona glomerulosa cells.
B) Aldosterone, a glucocorticoid, is produced by the zona reticularis cells.
C) Aldosterone, a mineralocorticoid, is produced by the zona glomerulosa.
D) Cortisol, a mineralocorticoid, is produced by the zona fasciculata cells.

Answer 18

C) Aldosterone, a mineralocorticoid, is produced by the zona glomerulosa.

Question 19

What class of hormones are hydrophobic and require a carrier protein molecule?
A) Steroid
B) Glycoprotein
C) Peptide
D) Amine

Answer 19

A) Steroid

Question 20

Which of the following hormones is secreted directly into the bloodstream?
A) Neurocrine
B) Exocrine
C) Endocrine
D) Paracrine

Answer 20

C) Endocrine