Endocrinology (Chemistry)

Question 1

A patient has the following test results:

increased serum calcium levels
decreased serum phosphate levels
increased levels of parathyroid hormone

This patient most likely has:

A) hyperparathyroidism
B) hypoparathyroidism
C) nephrosis
D) steatorrhea

Answer 1

A) hyperparathyroidism

Question 2

TSH is produced by the:

A) hypothalamus
B) pituitary gland
C) adrenal cortex
D) thyroid

Answer 2

B) pituitary gland

Question 3

A patient has the following thyroid profile:

total T4: decreased
free T4: decreased
thyroid peroxidase antibody: positive
TSH: increased

This patient most probably has:

A) hyperthyroidism
B) hypothyroidism
C) a normal thyroid
D) Graves disease

Answer 3

B) hypothyroidism

Question 4

A 45 year old woman complains of fatigue, heat intolerance and hair loss. Total and free T4 are abnormally low. If the TSH showed marked elevation, this would be consistent with:

A) Graves disease
B) an adenoma of the thyroid
C) thyrotoxicosis
D) primary hypothyroidism

Answer 4

D) primary hypothyroidism

Question 5

The majority of thyroxine (T4) is converted into the more biologically active hormone:

A) thyroglobulin
B) thyroid-stimulating hormone (TSH)
C) triiodothyronine (T3)
D) thyrotropin-releasing hormone

Answer 5

C) triiodothyronine (T3)

Question 6

A 2 year old child with a decreased serum T4 is described as being somewhat dwarfed, stocky, overweight, and having coarse features. Of the following, the most informative additional laboratory test would be the serum:

A) thyroxine-binding globulin (TBG)
B) thyroid-stimulating hormone (TSH)
C) triiodothyronine (T3)
D) cholesterol

Answer 6

B) thyroid-stimulating hormone (TSH)

Question 7

Assays for free T4 measure hormone not bound to thyroxine-binding prealbumin, thyroxine-binding globulin and:

A) thyrotropin-releasing hormone
B) albumin
C) free T3
D) thyroid-stimulating hormone

Answer 7

B) albumin

Question 8

The recommended initial thyroid function test for either a healthy, asymptomatic patient or patient with symptoms which may be related to a thyroid disorder is:

A) free thyroxine (free T4)
B) thyroid-stimulating hormone (TSH)
C) total thyroxine (T4)
D) triiodothyronine (T3)

Answer 8

B) thyroid-stimulating hormone (TSH)

Question 9

The screening test for congenital hypothyroidism is based upon:

A) free T4 level in the newborn
B) thyroid-binding globulin level in the newborn
C) thyroid-releasing hormone level in the newborn
D) total thyroxine (T4) level in the newborn

Answer 9

D) total thyroxine (T4) level in the newborn

Question 10

Which one of the following sets of results is consistent with primary hypothyroidism, (eg, Hashimoto thyroiditis):

Patient A:
TSH: decreased
T4 (free thyroxine): decreased
Antimicrosomal antibody: positive

Patient B:
TSH: increased
T4 (free thyroxine): increased
Antimicrosomal antibody: positive

Patient C:
TSH: normal
T4 (free thyroxine): decreased
Antimicrosomal antibody: negative

Patient D:
TSH: increased
T4 (free thyroxine): decreased
Antimicrosomal antibody: positive

A) Patient A
B) Patient B
C) Patient C
D) Patient D

Answer 10

D) Patient D

Question 11

A 68 year old female patient tells her physician of being “cold all the time” and recent weight gain, with no change in diet. The doctor orders a TSH level, and the laboratory reports a value of 8.7 uU/mL (8.7 IU/L) (reference range = 0.5-5.0 uU/mL [0.5-5.0 IU/L]). This patient most likely has:

A) primary hypothyroidism
B) Graves disease
C) a TSH-secreting tumor
D) primary hyperthyroidism

Answer 11

A) primary hypothyroidism

Question 12

Which of the following is secreted by the placenta and used for the early detection of pregnancy?

A) follicle-stimulating hormone (FSH)
B) human chorionic gonadotropin (HCG)
C) luteinizing hormone (LH)
D) progesterone

Answer 12

B) human chorionic gonadotropin (HCG)

Question 13

During pregnancy, the form of estrogen that predominates and may be useful in prenatal screening is:

A) estradiol
B) estriol
C) estrone
D) pregnanediol

Answer 13

B) estriol

Question 14

The hormone that triggers ovulation is:

A) follicle-stimulating hormone (FSH)
B) luteinizing hormone (LH)
C) thyroid-stimulating hormone (TSH)
D) human chorionic gonadotropin (HCG)

Answer 14

B) luteinizing hormone (LH)

Question 15

During a normal pregnancy, quantitative human chorionic gonadotropin (HCG) levels peak how many weeks after the last menstrual period?

A) 2-4
B) 8-10
C) 14-16
D) 18-20

Answer 15

B) 8-10

Question 16

Which of the following steroids is an adrenal cortical hormone?

A) angiotensinogen
B) aldosterone
C) epinephrine
D) growth hormone

Answer 16

B) aldosterone

Question 17

What common substrate is used in the biosynthesis of adrenal steroids, including androgens and estrogens?

A) cortisol
B) catecholamines
C) progesterone
D) cholesterol

Answer 17

D) cholesterol

Question 18

The biologically most active, naturally occurring androgen is:

A) androstenedione
B) cortisol
C) epiandrosterone
D) testosterone

Answer 18

D) testosterone

Question 19

Plasma for cortisol determinations were collected at 7 am, after waking the patient, and at 10 pm that evening. The cortisol level of the morning sample was higher than the evening sample. This is consistent with:

A) a normal finding
B) Cushing sundorme
C) Addison Disease
D) hypopituitaism

Answer 19

A) a normal finding

Question 20

The major action of angiotension II is:

A) increased pituitary secretion of vasopressin
B) increased vasoconstriction
C) increased parathormone secretion by the parathyroid
D) decreased adrenal secretion of aldosterone

Answer 20

B) increased vasoconstriction

Question 21

The urinary excretion product measured as an indicator of epinephrine production is:

A) dopamine
B) dihydroxyphenylalanine (DOPA)
C) homovanillic acid
D) vanillylmandelic acid (VMA)

Answer 21

D) vanillylmandelic acid (VMA)

Question 22

Test methodology for monitoring parathyroid glandular function in diagnosis of hypo- or hyperparathyroidism should be focused on assessing:

A) intact PTHrP molecule
B) the C-terminal PTH
C) intact PTH amino acids 1-84
D) N-terminal PTH amino acids 1-7

Answer 22

C) intact PTH amino acids 1-84

Question 23

The most common form (95%) of conenital adrenal hyperplasia is 21-hydroxylase deficiency which is detected by elevated plasma:

A) cortisol
B) aldosterone
C) 17-OH-progesterone
D) 11-deoxycortisol

Answer 23

C) 17-OH-progesterone

Question 24

A diagnosis of primary adrenal insufficiency requires demonstration of:

A) decreased urinary 17-keto- and 17-hydrozysteroids
B) decreased cortisol production
C) impaired response to ACTH stimulation
D) increased urincary cortisol excretion after metyrapone

Answer 24

C) impaired response to ACTH stimulation

Question 25

The screen for adrenal cortical hyperfunction with the greatest sensitivity and specificity is:

A) 24 hr urine free cortisol
B) plasma cortisol
C) urinary 17-hydroxycorticosteroids
D) plasma corticosterone

Answer 25

A) 24 hr urine free cortisol

Question 26

A patient has signs and symptoms suggestive of acromegaly. The diagnosis would be confirmed if the patient has which of the following?

A) an elevated serum phosphate concentration
B) a decreased serum growth hormone releasing factor concentration
C) no decrease in serum growth hormone concentration 90 minutes after oral glucose administration
D) an increased serum somatostatin concentration

Answer 26

C) no decrease in serum growth hormone concentration 90 minutes after oral glucose administration

Question 27

Estrogen and progesterone receptor assays are useful in identifying patients who are likely to benefit form endocrine therapy to treat which of the following?

A) ovarian cancer
B) breast cancer
C) endometriosis
D) amenorrhea

Answer 27

B) breast cancer

Question 28

Which of the following sample collections wouldd give an accurate assessment of potential excess cortisol production (hypercortisolism)?

A) collect a plasma sample as a baseline, and another 1-hour after administration of metyrapone
B) collect a plasma sample at 8 am only
C) collect a 24 hr urine free cortisol
D) collect a plasma sample at 8 am and at 8 am the next day

Answer 28

C) collect a 24 hr urine free cortisol

Question 29

How is primary hypercortisolism (Addison’s Disease) differentiated from secondary hypocrotisolism (of pituitary origin)?

A) adrenal corticotropic hormone (ACTH) is decreased in primary and elevated in secondary
B) adrenal corticotropic hormone (ACTH) is elevated in primary and decreased in secondary
C) low aldosterone and hypoglycemia present with secondary hypocrotisolism
D) normal cortisol levels and blood pressure with primary hypocortisolism

Answer 29

B) adrenal corticotropic hormone (ACTH) is elevated in primary and decreased in secondary

Question 30

Aldersteeerone is released by the adrenal cortex upon stimulation by:

A) renin
B) angiotensinogen
C) angiotensin I
D) angiotensin II

Answer 30

D) angiotensin II

Question 31

^125 I has a physical half-life of 60.0 days. A sample tested today had activity of 10,000 CPM/mL. How many days from today will the count be 1250 CPM/mL?

A) 60
B) 180
C) 240
D) 1250

Answer 31

B) 180

Question 32

A chemiluminescent EIA:

A) measures absorption of light
B) is less sensitive than radioisotopic reactions
C) is monitored by the use of a gamma counter
D) is quantitated by the amount of light produced by the reaction

Answer 32

D) is quantitated by the amount of light produced by the reaction