NR 507 — ALTERATIONS IN THE
ENDOCRINE SYSTEM Actual Exam
Complete Questions and Answers | 100%
Verified Detailed Rationales - Pass
Guaranteed - A+ Graded
TABLE OF CONTENTS
Section 1 | Hypothalamus and Pituitary Disorders | Q1 – Q10
Section 2 | Thyroid and Parathyroid Disorders | Q11 – Q20
Section 3 | Adrenal Disorders | Q21 – Q30
Section 4 | Pancreas and Diabetes Mellitus | Q31 – Q40
Section 5 | Endocrine Feedback Loops and Multisystem Integration | Q41 – Q50
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SECTION 1: HYPOTHALAMUS AND PITUITARY DISORDERS Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 38-year-old woman presents to her primary care provider with complaints of milky
nipple discharge despite not having been pregnant or breastfed in 8 years. She also
reports irregular menstrual periods and decreased libido. Laboratory studies reveal a
serum prolactin level of 145 ng/mL (normal < 25 ng/mL). MRI shows a 6 mm pituitary
adenoma. Which pathophysiologic mechanism best explains her clinical presentation?
A. Excessive growth hormone secretion causing acromegaly and metabolic
derangement
B. Excessive prolactin secretion causing hypogonadism through inhibition of GnRH
,C. Excessive ACTH secretion causing Cushing's disease and cortisol excess
D. Excessive TSH secretion causing hyperthyroidism and menstrual irregularity
Correct Answer: B
Rationale: A prolactin-secreting pituitary adenoma (prolactinoma) elevates prolactin,
which inhibits hypothalamic GnRH secretion, leading to decreased LH and FSH,
anovulation, amenorrhea or oligomenorrhea, galactorrhea, and decreased libido. Growth
hormone excess causes acromegaly with coarse facial features and enlarged
extremities, not galactorrhea. ACTH excess produces Cushing's disease with central
obesity and striae, while TSH excess is rare and causes hyperthyroidism without
galactorrhea.
Question 2 of 50
A 62-year-old man is evaluated for progressive fatigue, cold intolerance, and weight gain
over the past year. His free T4 is low and TSH is markedly elevated at 28 mIU/L. MRI
reveals a pituitary mass. Which type of pituitary disorder is most consistent with these
findings?
A. Primary hyperthyroidism from a TSH-secreting pituitary adenoma
B. Secondary hypothyroidism from pituitary destruction and TSH deficiency
C. Tertiary hypothyroidism from hypothalamic dysfunction and TRH deficiency
D. Primary hypothyroidism from autoimmune thyroiditis with pituitary enlargement
Correct Answer: B
Rationale: Secondary hypothyroidism occurs when pituitary disease destroys thyrotroph
cells, causing low T4 with inappropriately low or normal TSH, though some functional
pituitary masses can paradoxically present with complex hormonal profiles; however,
the key is that a pituitary mass causing hypothyroidism indicates secondary rather than
primary origin. Primary hypothyroidism would show elevated TSH with low T4 from
thyroid gland failure, and tertiary hypothyroidism involves hypothalamic TRH deficiency
,without a pituitary mass. The presence of a pituitary mass localizes the problem to the
pituitary.
Question 3 of 50
A 28-year-old woman presents with severe headaches, bitemporal hemianopsia, and
amenorrhea. MRI confirms a large pituitary macroadenoma compressing the optic
chiasm. Which hormone deficiency is most likely contributing to her amenorrhea?
A. Deficiency of antidiuretic hormone causing diabetes insipidus
B. Deficiency of gonadotropin-releasing hormone pulsatility from mass effect
C. Deficiency of growth hormone causing short stature and delayed puberty
D. Deficiency of oxytocin causing impaired uterine contraction and lactation
Correct Answer: B
Rationale: A pituitary macroadenoma compresses normal pituitary tissue and disrupts
the hypothalamic-pituitary portal system, impairing GnRH pulsatility and causing
gonadotropin deficiency, which manifests as amenorrhea, infertility, and decreased
estrogen. Diabetes insipidus from ADH deficiency causes polyuria and polydipsia, not
amenorrhea. Growth hormone deficiency in adults causes metabolic changes, not short
stature, and oxytocin deficiency does not cause amenorrhea.
Question 4 of 50
A 45-year-old man develops polyuria with a 24-hour urine output of 6 liters after
transsphenoidal surgery for a pituitary adenoma. His serum sodium is 150 mEq/L, urine
specific gravity is 1.002, and urine osmolality is 120 mOsm/kg. Which condition has he
developed?
A. Syndrome of inappropriate antidiuretic hormone from excess ADH secretion
B. Central diabetes insipidus from damage to the posterior pituitary or hypothalamus
C. Primary polydipsia from compulsive water drinking after surgery
D. Cerebral salt wasting from excessive natriuresis and volume depletion
, Correct Answer: B
Rationale: Transsphenoidal surgery commonly damages the posterior pituitary or
hypothalamic neurohypophyseal tract, causing central diabetes insipidus with
deficiency of ADH, which presents with dilute polyuria, hypernatremia, and low urine
osmolality. SIADH causes water retention with hyponatremia and concentrated urine,
the opposite of this presentation. Primary polydipsia causes dilutional hyponatremia,
not hypernatremia, and cerebral salt wasting causes hyponatremia with volume
contraction.
Question 5 of 50
A 16-year-old boy is referred to endocrinology because he has not experienced pubertal
changes despite his peers developing normally. He is 5'2" tall, has prepubertal testes,
and no pubic hair. His LH and FSH are low, and a GnRH stimulation test shows a blunted
response. Which diagnosis is most likely?
A. Constitutional delay of growth and puberty with eventual spontaneous development
B. Hypogonadotropic hypogonadism from deficient GnRH secretion or action
C. Hypergonadotropic hypogonadism from primary testicular failure
D. Growth hormone deficiency causing delayed puberty and short stature
Correct Answer: B
Rationale: Low gonadotropins with a blunted GnRH response indicate hypogonadotropic
hypogonadism, where the defect lies in the hypothalamus or pituitary failure to secrete
GnRH or gonadotropins, preventing pubertal development. Constitutional delay would
eventually show a normal GnRH response, and hypergonadotropic hypogonadism from
testicular failure would present with elevated LH and FSH. Growth hormone deficiency
causes short stature but does not prevent puberty if gonadotropins are intact.
Question 6 of 50
ENDOCRINE SYSTEM Actual Exam
Complete Questions and Answers | 100%
Verified Detailed Rationales - Pass
Guaranteed - A+ Graded
TABLE OF CONTENTS
Section 1 | Hypothalamus and Pituitary Disorders | Q1 – Q10
Section 2 | Thyroid and Parathyroid Disorders | Q11 – Q20
Section 3 | Adrenal Disorders | Q21 – Q30
Section 4 | Pancreas and Diabetes Mellitus | Q31 – Q40
Section 5 | Endocrine Feedback Loops and Multisystem Integration | Q41 – Q50
══════════════════════════════════════
SECTION 1: HYPOTHALAMUS AND PITUITARY DISORDERS Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 38-year-old woman presents to her primary care provider with complaints of milky
nipple discharge despite not having been pregnant or breastfed in 8 years. She also
reports irregular menstrual periods and decreased libido. Laboratory studies reveal a
serum prolactin level of 145 ng/mL (normal < 25 ng/mL). MRI shows a 6 mm pituitary
adenoma. Which pathophysiologic mechanism best explains her clinical presentation?
A. Excessive growth hormone secretion causing acromegaly and metabolic
derangement
B. Excessive prolactin secretion causing hypogonadism through inhibition of GnRH
,C. Excessive ACTH secretion causing Cushing's disease and cortisol excess
D. Excessive TSH secretion causing hyperthyroidism and menstrual irregularity
Correct Answer: B
Rationale: A prolactin-secreting pituitary adenoma (prolactinoma) elevates prolactin,
which inhibits hypothalamic GnRH secretion, leading to decreased LH and FSH,
anovulation, amenorrhea or oligomenorrhea, galactorrhea, and decreased libido. Growth
hormone excess causes acromegaly with coarse facial features and enlarged
extremities, not galactorrhea. ACTH excess produces Cushing's disease with central
obesity and striae, while TSH excess is rare and causes hyperthyroidism without
galactorrhea.
Question 2 of 50
A 62-year-old man is evaluated for progressive fatigue, cold intolerance, and weight gain
over the past year. His free T4 is low and TSH is markedly elevated at 28 mIU/L. MRI
reveals a pituitary mass. Which type of pituitary disorder is most consistent with these
findings?
A. Primary hyperthyroidism from a TSH-secreting pituitary adenoma
B. Secondary hypothyroidism from pituitary destruction and TSH deficiency
C. Tertiary hypothyroidism from hypothalamic dysfunction and TRH deficiency
D. Primary hypothyroidism from autoimmune thyroiditis with pituitary enlargement
Correct Answer: B
Rationale: Secondary hypothyroidism occurs when pituitary disease destroys thyrotroph
cells, causing low T4 with inappropriately low or normal TSH, though some functional
pituitary masses can paradoxically present with complex hormonal profiles; however,
the key is that a pituitary mass causing hypothyroidism indicates secondary rather than
primary origin. Primary hypothyroidism would show elevated TSH with low T4 from
thyroid gland failure, and tertiary hypothyroidism involves hypothalamic TRH deficiency
,without a pituitary mass. The presence of a pituitary mass localizes the problem to the
pituitary.
Question 3 of 50
A 28-year-old woman presents with severe headaches, bitemporal hemianopsia, and
amenorrhea. MRI confirms a large pituitary macroadenoma compressing the optic
chiasm. Which hormone deficiency is most likely contributing to her amenorrhea?
A. Deficiency of antidiuretic hormone causing diabetes insipidus
B. Deficiency of gonadotropin-releasing hormone pulsatility from mass effect
C. Deficiency of growth hormone causing short stature and delayed puberty
D. Deficiency of oxytocin causing impaired uterine contraction and lactation
Correct Answer: B
Rationale: A pituitary macroadenoma compresses normal pituitary tissue and disrupts
the hypothalamic-pituitary portal system, impairing GnRH pulsatility and causing
gonadotropin deficiency, which manifests as amenorrhea, infertility, and decreased
estrogen. Diabetes insipidus from ADH deficiency causes polyuria and polydipsia, not
amenorrhea. Growth hormone deficiency in adults causes metabolic changes, not short
stature, and oxytocin deficiency does not cause amenorrhea.
Question 4 of 50
A 45-year-old man develops polyuria with a 24-hour urine output of 6 liters after
transsphenoidal surgery for a pituitary adenoma. His serum sodium is 150 mEq/L, urine
specific gravity is 1.002, and urine osmolality is 120 mOsm/kg. Which condition has he
developed?
A. Syndrome of inappropriate antidiuretic hormone from excess ADH secretion
B. Central diabetes insipidus from damage to the posterior pituitary or hypothalamus
C. Primary polydipsia from compulsive water drinking after surgery
D. Cerebral salt wasting from excessive natriuresis and volume depletion
, Correct Answer: B
Rationale: Transsphenoidal surgery commonly damages the posterior pituitary or
hypothalamic neurohypophyseal tract, causing central diabetes insipidus with
deficiency of ADH, which presents with dilute polyuria, hypernatremia, and low urine
osmolality. SIADH causes water retention with hyponatremia and concentrated urine,
the opposite of this presentation. Primary polydipsia causes dilutional hyponatremia,
not hypernatremia, and cerebral salt wasting causes hyponatremia with volume
contraction.
Question 5 of 50
A 16-year-old boy is referred to endocrinology because he has not experienced pubertal
changes despite his peers developing normally. He is 5'2" tall, has prepubertal testes,
and no pubic hair. His LH and FSH are low, and a GnRH stimulation test shows a blunted
response. Which diagnosis is most likely?
A. Constitutional delay of growth and puberty with eventual spontaneous development
B. Hypogonadotropic hypogonadism from deficient GnRH secretion or action
C. Hypergonadotropic hypogonadism from primary testicular failure
D. Growth hormone deficiency causing delayed puberty and short stature
Correct Answer: B
Rationale: Low gonadotropins with a blunted GnRH response indicate hypogonadotropic
hypogonadism, where the defect lies in the hypothalamus or pituitary failure to secrete
GnRH or gonadotropins, preventing pubertal development. Constitutional delay would
eventually show a normal GnRH response, and hypergonadotropic hypogonadism from
testicular failure would present with elevated LH and FSH. Growth hormone deficiency
causes short stature but does not prevent puberty if gonadotropins are intact.
Question 6 of 50
