NR 507 Advanced Pathophysiology Week 6
Exam: Endocrine System Disorders 100
Questions with Answers and Rationales
SECTION A: Hypothalamic-Pituitary Disorders (Questions 1-
20)
1. A 35-year-old female presents with amenorrhea,
galactorrhea, and headaches. MRI reveals a pituitary
adenoma. Which hormone is most likely elevated?
A) Growth hormone (GH)
B) Prolactin
C) Adrenocorticotropic hormone (ACTH)
D) Thyroid-stimulating hormone (TSH)
Correct Answer: B) Prolactin
Expert Rationale: Prolactin-secreting pituitary adenomas
(prolactinomas) are the most common pituitary tumors. The classic
triad includes amenorrhea, galactorrhea, and headaches. Elevated
prolactin inhibits GnRH, leading to hypogonadism .
2. A patient with a pituitary adenoma presents with visual
field defects. Which visual field defect is most characteristic
of a pituitary tumor?
,A) Homonymous hemianopia
B) Bitemporal hemianopia
C) Central scotoma
D) Monocular blindness
Correct Answer: B) Bitemporal hemianopia
Expert Rationale: Pituitary tumors compress the optic chiasm,
affecting the crossing nasal fibers, resulting in bitemporal
hemianopia. This is loss of vision in the temporal fields of both eyes .
3. A 45-year-old male presents with headaches, coarse facial
features, enlarged hands and feet, and deepening of his voice.
These findings are most consistent with:
A) Pituitary dwarfism
B) Acromegaly
C) Gigantism
D) Cushing syndrome
Correct Answer: B) Acromegaly
Expert Rationale: Acromegaly results from excessive growth
hormone in adults after epiphyseal plate closure. The classic
features include coarsening of facial features, enlarged hands and
feet (acral enlargement), deepening of the voice, and organomegaly
.
4. A patient is diagnosed with diabetes insipidus. Which of
the following laboratory findings would be expected?
,A) High serum osmolality and low urine osmolality
B) Low serum osmolality and high urine osmolality
C) High serum osmolality and high urine osmolality
D) Low serum osmolality and low urine osmolality
Correct Answer: A) High serum osmolality and low urine
osmolality
Expert Rationale: Diabetes insipidus is characterized by insufficient
ADH (central) or renal resistance to ADH (nephrogenic), leading to
failure to concentrate urine. Serum osmolality is elevated (>295
mOsm/kg), and urine osmolality is low (<300 mOsm/kg) .
5. A 30-year-old woman presents with severe headaches,
visual disturbances, and galactorrhea. Serum prolactin is
markedly elevated. Which of the following is the most
appropriate initial treatment?
A) Transsphenoidal surgery
B) Dopamine agonist (bromocriptine or cabergoline)
C) Radiation therapy
D) Octreotide
Correct Answer: B) Dopamine agonist (bromocriptine or
cabergoline)
Expert Rationale: Dopamine agonists are first-line treatment for
prolactinomas. They reduce prolactin levels and shrink tumor size.
Surgery is reserved for patients who do not respond to medical
therapy or have complications .
, 6. Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
is characterized by:
A) Hypernatremia and high urine output
B) Hyponatremia and concentrated urine
C) Hypernatremia and diluted urine
D) Hyponatremia and diluted urine
Correct Answer: B) Hyponatremia and concentrated urine
Expert Rationale: SIADH involves excess ADH secretion, leading to
water retention, dilutional hyponatremia, concentrated urine, and
euvolemia. Treatment includes fluid restriction and sometimes
hypertonic saline or vasopressin receptor antagonists .
7. Which of the following is a cause of central diabetes
insipidus?
A) Lithium therapy
B) Head trauma
C) Hypercalcemia
D) Hypokalemia
Correct Answer: B) Head trauma
Expert Rationale: Central diabetes insipidus results from
insufficient ADH production, often due to head trauma, pituitary
surgery, tumors, or idiopathic causes. Lithium and hypercalcemia
cause nephrogenic diabetes insipidus .
Exam: Endocrine System Disorders 100
Questions with Answers and Rationales
SECTION A: Hypothalamic-Pituitary Disorders (Questions 1-
20)
1. A 35-year-old female presents with amenorrhea,
galactorrhea, and headaches. MRI reveals a pituitary
adenoma. Which hormone is most likely elevated?
A) Growth hormone (GH)
B) Prolactin
C) Adrenocorticotropic hormone (ACTH)
D) Thyroid-stimulating hormone (TSH)
Correct Answer: B) Prolactin
Expert Rationale: Prolactin-secreting pituitary adenomas
(prolactinomas) are the most common pituitary tumors. The classic
triad includes amenorrhea, galactorrhea, and headaches. Elevated
prolactin inhibits GnRH, leading to hypogonadism .
2. A patient with a pituitary adenoma presents with visual
field defects. Which visual field defect is most characteristic
of a pituitary tumor?
,A) Homonymous hemianopia
B) Bitemporal hemianopia
C) Central scotoma
D) Monocular blindness
Correct Answer: B) Bitemporal hemianopia
Expert Rationale: Pituitary tumors compress the optic chiasm,
affecting the crossing nasal fibers, resulting in bitemporal
hemianopia. This is loss of vision in the temporal fields of both eyes .
3. A 45-year-old male presents with headaches, coarse facial
features, enlarged hands and feet, and deepening of his voice.
These findings are most consistent with:
A) Pituitary dwarfism
B) Acromegaly
C) Gigantism
D) Cushing syndrome
Correct Answer: B) Acromegaly
Expert Rationale: Acromegaly results from excessive growth
hormone in adults after epiphyseal plate closure. The classic
features include coarsening of facial features, enlarged hands and
feet (acral enlargement), deepening of the voice, and organomegaly
.
4. A patient is diagnosed with diabetes insipidus. Which of
the following laboratory findings would be expected?
,A) High serum osmolality and low urine osmolality
B) Low serum osmolality and high urine osmolality
C) High serum osmolality and high urine osmolality
D) Low serum osmolality and low urine osmolality
Correct Answer: A) High serum osmolality and low urine
osmolality
Expert Rationale: Diabetes insipidus is characterized by insufficient
ADH (central) or renal resistance to ADH (nephrogenic), leading to
failure to concentrate urine. Serum osmolality is elevated (>295
mOsm/kg), and urine osmolality is low (<300 mOsm/kg) .
5. A 30-year-old woman presents with severe headaches,
visual disturbances, and galactorrhea. Serum prolactin is
markedly elevated. Which of the following is the most
appropriate initial treatment?
A) Transsphenoidal surgery
B) Dopamine agonist (bromocriptine or cabergoline)
C) Radiation therapy
D) Octreotide
Correct Answer: B) Dopamine agonist (bromocriptine or
cabergoline)
Expert Rationale: Dopamine agonists are first-line treatment for
prolactinomas. They reduce prolactin levels and shrink tumor size.
Surgery is reserved for patients who do not respond to medical
therapy or have complications .
, 6. Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
is characterized by:
A) Hypernatremia and high urine output
B) Hyponatremia and concentrated urine
C) Hypernatremia and diluted urine
D) Hyponatremia and diluted urine
Correct Answer: B) Hyponatremia and concentrated urine
Expert Rationale: SIADH involves excess ADH secretion, leading to
water retention, dilutional hyponatremia, concentrated urine, and
euvolemia. Treatment includes fluid restriction and sometimes
hypertonic saline or vasopressin receptor antagonists .
7. Which of the following is a cause of central diabetes
insipidus?
A) Lithium therapy
B) Head trauma
C) Hypercalcemia
D) Hypokalemia
Correct Answer: B) Head trauma
Expert Rationale: Central diabetes insipidus results from
insufficient ADH production, often due to head trauma, pituitary
surgery, tumors, or idiopathic causes. Lithium and hypercalcemia
cause nephrogenic diabetes insipidus .
