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1.39: Endocrinology

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    38619
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    1. Increased urinary 17-hydroxycorticosteroids are observed in:
      1. Cushing’s syndrome
      2. Addison’s disease
      3. hypopituitarism
      4. nephrosis
      5. decreased function of hypothalamus
    2. A person having an abnormally low serum cortisol baseline level is given ACTH. A subsequent serum cortisol measurement taken 1 hour after ACTH shows no change in the serum cortisol level. The most probable diagnosis of the patient
      1. Cushing’s syndrome
      2. Addison’s disease
      3. adrenal tumor
      4. hypopituitansm
      5. hypoactive hypothalamus
    3. In chronic thyroiditis, circulating antibodies against the storage protein for T3 and T4 are frequently found. This storage protein is:
      1. triiodothyronine
      2. thyroid binding globulin
      3. thyroglobulin
      4. thyroxine binding pre-albumin
      5. thyrotropin
    4. Progesterone is secreted:
      1. by the endometrium during the last 2 weeks of the menstrual cycle
      2. by the anterior pituitary during the last 2 weeks of the menstrual cycle
      3. by the corpus luteum during ‘the last 2 weeks of the menstrual cycle
      4. by the graafian follicle during the first week of the menstrual cycle
      5. by the hypothalamus during the entire menstrual cycle
    5. Aldosterone, a steroid hormone synthesized in the adrenal medulla, controls which of the following?:
      1. electrolyte reabsorption in the proximal tubule
      2. active Cl- reabsorption in the loop of Henle
      3. Na+/K+(H+) pump in the distal tubule (Na+ being reabsorbed
      4. water reabsorption in collecting ducts
      5. urinary calcium excretion
    6. Anti-diuretic hormone (arginine vasopressin), a polypeptide hormone synthesized in the pituitary gland, controls which of the following?:
      1. electrolyte reabsorption in the proximal tubule
      2. active Cl- reabsorption in the loop of Henle
      3. Na+/K+(H+) pump in the distal tubule (Na+ being reabsorbed)
      4. water reabsorption in the collecting ducts of the nephron
      5. blood pressure
    7. Gastrin is a hormone which controls production of:
      1. renin
      2. mucus
      3. HCl
      4. lipase
      5. amylase
    8. Ovulation can be detected by immunoassay of which of the following hormones?:
      1. LH
      2. FSH
      3. estrogen
      4. progesterone
      5. testosterone
    9. The most important metabolite of epinephrine and norepinephrine is:
      1. homovanillic acid
      2. vanillylmandelic acid
      3. dopamine
      4. 5-hydroxyindole acetic acid
      5. serotonin
    10. Which of the following is not used to assist the reproduction desires of infertile couples?
      1. LH-RH
      2. IVF
      3. GIFT
      4. ZIFT
      5. ICSI

    Use the following key for Questions 11-14:

    1. increased
    2. decreased
    3. no change

    With polycystic ovarian disease, the ovary produces excessive quantities of androgens. Indicate what changes in hormone production would occur for the hormones listed below:

    1. progesterone
    2. testosterone
    3. estradiol
    4. FSH
    5. In hyperparathyroidism, plasma immunoreactive PTH will be:
      1. normal
      2. absent
      3. elevated
      4. present at a low level
      5. fluctuating over a wide range, from very low to very high
    6. There is no endocrine hormone from which of the following chemical classes?:
      1. proteins
      2. amino acids
      3. steroids
      4. polypeptides
      5. carbohydrates
    7. Hormones are carried in blood by which of the following mechanisms?
      1. in chylomicrons
      2. non-covalently bound to protein
      3. covalently bound to protein
      4. covalently bound to carbohydrates
      5. non-covalently lipids
    8. Which of the following hormones act by way of the “second” messenger, cyclic AMP?
      1. cortisol
      2. testosterone
      3. insulin
      4. thyroxin
      5. progesterone
    9. The hypothalamic-pituitary axis cannot be stimulated by:
      1. positive feedback loop
      2. negative feedback loop
      3. direct CNS stimulation
      4. direct CNS inhibition
      5. insulin
    10. A physician want to order thyroid function tests on an acutely ill, hospitalized patient suspected of being hypothyroid. The best advice would be to:
      1. Order a 3rd generation TSH test
      2. Order measurements of free T3
      3. Order a TRH challenge test
      4. Wait until the illness is over before performing the thyroid investigation
      5. Immediately treat with thyroid replacement therapy
    11. The precursor molecule of all estrogens and androgens is:
      1. androstenedione
      2. progesterone
      3. dehydroepiendrosterone
      4. 20,22 despregnenolone
      5. cholesterol
    12. In the male, increased FSH and LH and decreased testosterone is most likely associated with:
      1. primary hypergonadism
      2. secondary hypergonadism
      3. primary hypogonadism
      4. secondary hypogonadism
      5. normal function
    13. Elevated T4 and lowered T3 uptake together suggest the likelihood of:
      1. hyperthyroidism
      2. decreased TBG
      3. hypothyroidism
      4. decreased TBG
      5. hyperthyroidism of pregnancy
    14. Decreased T4 and decreased T3 uptake together suggest the likelihood of:
      1. hyperthyroidism
      2. increased TBG
      3. hypothyroidism
      4. decreased TBG
      5. secondary hyperthyroidism
    15. TSH is secreted by the:
      1. anterior pituitary
      2. posterior pituitary
      3. hypothalamus
      4. adrenal cortex
      5. thyroid gland
    16. Pregnancy, estrogen therapy, and oral contraceptives characteristically:
      1. cause hyperthyroidism
      2. cause hypothyroidism
      3. have no effect on circulating T4 concentration
      4. increase circulating TBG
      5. change levels of circulating free T4
    17. Most of the circulating T4 and T3 is bound to:
      1. thyroxine-binding prealbumin
      2. thyroxine-binding globulin
      3. albumin
      4. thyroglobulin
      5. none of the above
    18. A serum TSH level five times upper limit of normal in the presence of a low T4 and low T3 uptake:
      1. establishes the thyroid as the cause of hypothyroidism
      2. rules out the thyroid as the cause of hypothyroidism
      3. establishes the pituitary as the cause of hypothyroidism
      4. establishes the diagnosis of secondary hyperthyroidism
      5. fails to do any of the above

    Use the following Key to answer Questions 29—38:

    1. 1, 2, and 3 are correct
    2. 1 and 3 are correct
    3. 2 and 4 are correct
    4. 4 only is correct
    5. all are correct
    1. Screening for thyroid disease may be appropriate for which of the following populations?
      1. Newborns
      2. First trimester pregnant women
      3. Individuals older than 60 years
      4. All individuals of all ages
    2. Which of the following hormone(s) is/are from the adenohypophysis?:
      1. thyrocalcitonin
      2. serotonin
      3. glucagon
      4. ACTH
    3. Which of the following hormones are produced by the pituitary gland?:
      1. FSH
      2. growth hormone
      3. thyroid stimulating hormone
      4. adrenocorticotrophic hormone
    4. Which of the following describe the hypothalamic hormones? They:
      1. are small peptides
      2. are not affected by direct CNS stimulation
      3. act as releasing factors or inhibitors of pituitary hormone release
      4. act directly on all endocrine glands
    5. Steroid hormones are transported in blood:
      1. covalently bound to protein
      2. as free hormones
      3. in red blood cells
      4. non-covalently bound to specific proteins
    6. Hirsutism can be associated with:
      1. normal endocrine function
      2. menopause
      3. the polycystic ovary syndrome
      4. feminizing tumors
    7. Which of the following is (are) considered the active form of steroid hormones in plasma?
      1. Hormones bound only to specific transport proteins
      2. Hormones weakly bound to albumin
      3. Free hormone that has been glucuronated
      4. Hormone not bound to any protein
    8. Increases in which of the following are associated with a pheochromocytoma?:
      1. urinary metanephrines
      2. plasma aldosterone
      3. urinary VMA
      4. urinary 17-hydroxysteroids
    9. The production of T3 and T4 is normally influenced by which of the following?:
      1. plasma T3 concentration
      2. plasma T4 concentration
      3. TSH
      4. plasma thyroglobulin
    10. The hormone TSH performs which of the following actions?
      1. stimulates production of thyroid hormones (T4 and T3)
      2. promotes iodide organification by the thyroid gland
      3. promotes release. of T4 and T3 from the thyroid
      4. increases when TRH levels increase
    11. Aldosterone is secreted by which of the following parts of the adrenal gland
      1. the chromaffin cells
      2. the zona glomerulosa
      3. the zona fasciculata
      4. the zona reticularis
      5. the adrenal medulla
    12. Which one of the factors listed below does not directly stimulate aldosterone release?
      1. hypokalemia
      2. ACTH
      3. angiotensin II
      4. angiotensin III
      5. ACTH
    13. Which of the following androgens is secreted by the adrenal cortex in approximately equal quantities to cortisol?
      1. pregnenolone
      2. DHEA sulfate
      3. androstenedione
      4. testosterone
      5. dihydrotestosterone
    14. Which one of the following steroids is the immediate precursor to testosterone in the steroid hormone synthetic pathway?
      1. DHEA
      2. DHEA sulfate
      3. Androstenedione
      4. Pregnenolone
      5. dihydrotestosterone
    15. Which of the following is not a physiological property of cortisol?
      1. increases gluconeogenesis
      2. increases lipolysis
      3. increases protein catabolism
      4. stimulates leukocyte migration to sites of injury
      5. inhibits phagocytosis
    16. Which of the following regarding the steroid synthetic pathway is not correct?
      1. cholesterol is converted to pregnenolone
      2. 11 deoxycortisol is converted to cortisol
      3. pregnenolone is converted to progesterone
      4. androstenedione is converted to testosterone
      5. 17 hydroxyprogesterone is converted to aldosterone
    17. Cortisol has only weak mineralocorticoid activity in the kidney because
      1. it has low affinity for the aldosterone receptor
      2. it is rapidly converted by an enzyme in the renal cell to inactive cortisone
      3. it can not enter the renal cell
      4. it is in too low concentration
      5. it is very rapidly filtered through the glomerulus and is therefore ineffective.
    18. Which of the following does not stimulate cortisol release?
      1. hyperglycemia
      2. severe illness
      3. trauma
      4. major depression
      5. interleukin-1
    19. The most common cause of Addison’s disease in North America is
      1. tuberculosis
      2. hemochromatosis
      3. infarction
      4. adrenoleukodystrophy
      5. autoimmune destruction (adrenalitis)
    20. A patient presents to the emergency department with profound postural hypotension, hyponatremia, hyperkalemia, and his skin is darker than usual. Which of the following diagnostic tests should be carried out as soon as possible?
      1. baseline serum cortisol measurement
      2. plasma ACTH measurement
      3. urine free cortisol
      4. short ACTH stimulation test
      5. dexamethasone suppression test
    21. Which one of the following observations are not consistent with the diagnosis of Conn’s sydrome?
      1. low serum potassium
      2. high urine potassium excretion
      3. polyuria and polydipsia
      4. hypertension
      5. high plasma renin activity
    22. The most specific procedure for localizing aldosterone secreting adenomas (Conn’s syndrome) is
      1. bilateral adrenal venous catheterization and measuring aldosterone
      2. nuclear medicine imaging using radioactively labelled iodocholesterol
      3. aldosterone response to postural change
      4. abdominal CAT scan
      5. abdominal palpation

    The following statement concerns questions 51 and 52. A new born female child is born with ambiguous genitalia and develops hyponatremia, hyperkalemia, and hypotension shortly after birth.

    1. Which of the following is the most likely cause of her problem?
      1. autoimmune destruction of the adrenal gland
      2. infarction of the adrenal gland
      3. 21 hydroxylase deficiency
      4. 11 hydroxylase deficiency
      5. 17 hydroxylase deficiency
    2. Which of the following diagnostic tests will confirm the diagnosis in the case described above?
      1. short ACTH stimulation test
      2. cortisol measurement
      3. testosterone measurement
      4. aldosterone measurement
      5. 17- hydroxyprogesterone
    3. Which of the following causes of congenital adrenal hyperplasia is associated with hypertension, ambiguous genitalia in females and precocious puberty in males.
      1. 21-hydroxylase deficiency
      2. 11-hydroxylase deficiency
      3. 17 hydroxylase deficiency
      4. 3 beta-hydroxysteroid dehydrogenase deficiency
    4. Which one of the following hormones can not be expressed ectopically by tumours?
      1. ACTH
      2. Antidiuretic hormone (ADH)
      3. Growth hormone releasing hormone (GHRH)
      4. Corticotrophin releasing hormone (CRH)
      5. Cortisol
    5. A patient presents with hypertension, central obesity, abdominal striae, muscle weakness, and moon face. Which of the following tests would be most useful to perform first?
      1. ACTH
      2. aldosterone
      3. random serum cortisol
      4. 1 mg overnight dexamethasone suppression test
      5. CRH stimulation test
    6. A patient with confirmed Cushing’s syndrome has the following results. The urine free cortisol and serum cortisol measurements are elevated but do not suppress when given a high dose (8 mg) of dexamethasone. The ACTH is however unmeasurable. These results are suggestive of which of the following causes of Cushing’s syndrome?
      1. adrenal adenoma
      2. pituitary adenoma
      3. bronchial carcinoma
      4. bronchial carcinoid
      5. pheochromocytoma
    7. A patient with confirmed Cushing’s sydrome has the following results. The urine free cortisol and serum cortisol measurements are elevated but suppress by more than 90% after being given 8mg of dexamethasone. The plasma ACTH concentration is slightly higher than the upper limit of normal. These results are suggestive of which cause of Cushing’s syndrome?
      1. adrenal adenoma
      2. pituitary adenoma
      3. bronchial carcinoid
      4. bronchial carcinoma
      5. ectopic secretion of ACTH
    8. Which of the following is the most specific procedure to differentiate between an ectopic source and pituitary source of ACTH in a patient with Cushing’s syndrome?
      1. high dose dexamethasone suppression test
      2. ACTH concentration
      3. radiological imaging of the pituitary
      4. MRI imaging of the pituitary
      5. petrosal sinus sampling of ACTH concentration
    9. The best test to assess adrenal reserve in a patient withdrawn from long term glucocorticoid therapy is which of the following?
      1. morning serum cortisol
      2. urine free cortisol
      3. insulin hypoglycemia stimulation test
      4. ACTH stimulation test
      5. aldosterone
    10. Which of the following statements regarding cortisol is false?
      1. Cortisol levels vary throughout the day, usually highest in the morning and lowest in the evening
      2. Normally 90% of cortisol is bound to cortisol binding globulin
      3. Long term exposure to high levels of cortisol can lead to osteoporosis
      4. Cortisol reduces the rate of elimination of free water by decreasing the GFR.
      5. Cortisol levels are increased by psychological stress
    11. The rate limiting step in the biosynthesis of cortisol which is stimulated by ACTH is which of the following?
      1. the conversion of cholesterol to pregnenolone
      2. the conversion of pregnenolone to progesterone
      3. the conversion of progesterone to 17 hydroxyprogesterone
      4. the conversion of 17 hydroxyprogesterone to 11 deoxycortisol
      5. the conversion of 11 deoxycortisol to cortisol
    12. Which one of the following findings is not common to both primary and secondary adrenal insufficiency?
      1. low cortisol
      2. possible hypoglycemia
      3. weakness
      4. anorexia
      5. hyperpigmentation
    13. Which of the following endocrine abnormalities is not commonly associated with multiple endocrine neoplasia (MEN) type 1?
      1. hyperparathyroidism
      2. pituitary tumours
      3. pancreatic islet cell tumours
      4. pheochromocytoma
    14. Which of the following endocrine abnormalities is not commonly associated with multiple endocrine neoplasia (MEN) type 2A?
      1. pituitary tumours
      2. medullary carcinoma of the thyroid
      3. pheochromocytoma
      4. hyperparathyroidism
    15. Which of the following endocrine abnormalities is commonly associated with multiple endocrine neoplasia (MEN) type 2B?
      1. pituitary tumours
      2. pheochromocytoma
      3. pancreatic islet tumours
      4. hyperparathyroidism
    16. The most important symptom associated with pheochromocytoma is
      1. cardiac palpitations
      2. increased sweating
      3. headache
      4. increased anxiety
      5. sustained or episodic hypertension
    17. A patient presents with increased sweating, episodic hypertension, palpitations, headache, and anxiety. Physical examination and thyroid testing have ruled out hyperthyroidism as a possible cause. Which one of the following approaches would be best at this point.
      1. measure plasma epinephrine and norepinephrine
      2. collect a 24 hour urine specimen and measure vanillylmandelic acid (VMA)
      3. collect a 24 hour urine specimen and measure urine catecholamines or metanephrines
      4. perform a clonidine suppression test
      5. collect a 24 hour urine and measure dopamine
    18. The enzyme which converts norepinephrine to epinephrine in the adrenal medulla is a/an
      1. hydroxylase
      2. decarboxylase
      3. oxidase
      4. methyltransferase

    Use the following key for questions 69-73

    1. increased
    2. decreased
    3. no change

    Indicate the changes in hormone level that would occur in male primary
    hypogonadism for the hormones listed below.

    1. FSH
    2. total testosterone
    3. SHBG
    4. free T4
    5. LH

    Use the following key to answer question 74 and 75,

    1. 1, 2 and 3 are correct
    2. 1 and 3 are correct
    3. 2 and 4 are correct
    4. 4 only is correct
    5. all are correct
    1. An elevated serum prolactin level can be associated with:
      1. a pituitary tumor
      2. some drugs
      3. PCOS
      4. hyperthyroidism
    2. SHBG concentrations are increased by:
      1. obesity
      2. pregnancy
      3. androgens
      4. hyperthyroidism
      5. hyperprolactinemia

    Which of the following statements is true/false:

    1. Measurement of serum FSH levels is a reliable indicator of the perimenopausal state.
      1. True
      2. False
    2. In females, inhibin A and inhibin B play an important role in the regulation of FSH secretion.
      1. True
      2. False
    3. In testicular feminization syndrome the karotype is that of a normal female.
      1. True
      2. False
    4. In a male patient with low testosterone levels, FSH and LH levels within the reference range are not consistent with secondary hypogonadism.
      1. True
      2. False
    Answer
    1. a (p. 891)
    2. b (p. 897)
    3. c (p. 830-831, 839)
    4. c (p. 856-857)
    5. c (p. 879-880)
    6. d (p. 821)
    7. c (p. 812)
    8. a (p. 856)
    9. b (p. 883)
    10. a (p. 874)
    11. c (p. 683)
    12. a (p. 683)
    13. c (p. 683)
    14. b (p. 683)
    15. c (p. 527, 814-815)
    16. e (p. 811)
    17. b (p. 817-818)
    18. c (p. 813-814)
    19. e (p. 814-815)
    20. d (p. 837, 846)
    21. e (p. 854)
    22. c (p. 868)
    23. e (p. 840)
    24. c (p. 841)
    25. c (p. 812)
    26. d (p. 836)
    27. b (p. 832)
    28. a (p. 841)
    29. a (p. 838, 840, 841)
    30. d (p. 812)
    31. e (p. 812)
    32. b (p. 812, 823)
    33. d (p. 817)
    34. b (p. 863)
    35. c (p. 816-818, 820, 832)
    36. b (p. 890)
    37. a (p. 835)
    38. e (p. 835)
    39. b (p.812, 879 )
    40. a (p. 459, 885)
    41. a (p. 881)
    42. c (p. 882)
    43. d (p. 880)
    44. e (p. 882)
    45. b (p. 880)
    46. a (p. 879, 890)
    47. e (p. 898)
    48. d (p. 897)
    49. e (p. 895-896)
    50. a (p. 896)
    51. c (p. 888-889)
    52. e (p. 888)
    53. b (p. 889)
    54. e (p. 882)
    55. d (p. 891)
    56. a (p. 886)
    57. b (p. 894)
    58. e (p. 894-895)
    59. c (p. 897-898)
    60. d (p. 880)
    61. a (p. 881)
    62. e (p. 889-890)
    63. d (p. 890)
    64. a (p. 890)
    65. b (p. 890)
    66. e (p. 890-891)
    67. c (p. 890-891, 898-899)
    68. d (p. 883)
    69. a (p. 867, 868)
    70. b (p. 867, 868)
    71. a (p. 866-867, 868)
    72. c (p. 867, 868)
    73. a (p. 867, 868)
    74. a (p. 860-864)
    75. b (p. 855)
    76. b (p. 858)
    77. a (p. 855)
    78. b (p. 869)
    79. b (p. 868)

    1.39: Endocrinology is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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