NSG 3850 EXAM 3 PATHOPHYSIOLOGY
REVIEW QUESTIONS AND ANSWERS
1. Which physiological mechanism best describes the development of secondary
hyperparathyroidism in Chronic Kidney Disease (CKD)?
A. Excessive production of parathyroid hormone-related protein (PTHrP) by renal tumors
B. Hypercalcemia leading to feedback inhibition of the parathyroid gland
C. Hypocalcemia resulting from decreased activation of Vitamin D and phosphate retention
D. Primary hyperplasia of the chief cells due to genetic mutations
Answer: C
Conceptual Explanation: In CKD, the kidneys cannot convert Vitamin D to its active form
(calcitriol) and fail to excrete phosphate. Low calcitriol and high phosphate lead to
hypocalcemia, which stimulates the parathyroid glands to overproduce PTH.
2. A patient with a pituitary tumor presents with galactorrhea, amenorrhea, and visual field
disturbances. Which hormone is most likely being oversecreted?
A. Growth Hormone (GH)
B. Thyroid Stimulating Hormone (TSH)
,C. Adrenocorticotropic Hormone (ACTH)
D. Prolactin
Answer: D
Conceptual Explanation: Hyperprolactinemia causes galactorrhea (milk production) and
inhibits GnRH, leading to amenorrhea. Visual field disturbances (bitemporal hemianopsia)
occur due to the tumor compressing the optic chiasm.
3. Which pathological feature distinguishes Crohn’s disease from Ulcerative Colitis?
A. Transmural inflammation and skip lesions
B. Continuous lesions starting from the rectum
C. Involvement restricted to the mucosal layer only
D. Universal presence of bloody diarrhea
Answer: A
Conceptual Explanation: Crohn’s disease involves all layers of the bowel wall
(transmural) and exhibits skip lesions (patchy areas of inflammation), whereas Ulcerative
Colitis is typically continuous and limited to the mucosa.
4. In the pathogenesis of Type 1 Diabetes Mellitus, what is the primary cause of insulin
deficiency?
A. Amyloid deposition in the Islets of Langerhans
B. Downregulation of insulin receptors on peripheral tissues
, C. Hypersecretion of glucagon from alpha cells inhibiting insulin release
D. T-cell mediated autoimmune destruction of pancreatic beta cells
Answer: D
Conceptual Explanation: Type 1 Diabetes is an autoimmune disorder where CD8+ T-cells
and autoantibodies destroy pancreatic beta cells, leading to an absolute lack of insulin.
5. A patient presents with a ‘moon face,’ buffalo hump, and purple striae. Lab results show
elevated cortisol and low ACTH. What is the most likely diagnosis?
A. Adrenal Adenoma
B. Addison’s Disease
C. Ectopic ACTH Syndrome
D. Cushing’s Disease
Answer: A
Conceptual Explanation: Elevated cortisol with low ACTH indicates a primary adrenal
cause (like an adenoma) where the adrenal gland is autonomously secreting cortisol,
providing negative feedback to the pituitary to lower ACTH.
6. What is the underlying pathophysiology of Myasthenia Gravis?
A. Autoantibodies against acetylcholine receptors at the neuromuscular junction
B. Demyelination of the peripheral nervous system
C. Destruction of dopamine-producing neurons in the substantia nigra
REVIEW QUESTIONS AND ANSWERS
1. Which physiological mechanism best describes the development of secondary
hyperparathyroidism in Chronic Kidney Disease (CKD)?
A. Excessive production of parathyroid hormone-related protein (PTHrP) by renal tumors
B. Hypercalcemia leading to feedback inhibition of the parathyroid gland
C. Hypocalcemia resulting from decreased activation of Vitamin D and phosphate retention
D. Primary hyperplasia of the chief cells due to genetic mutations
Answer: C
Conceptual Explanation: In CKD, the kidneys cannot convert Vitamin D to its active form
(calcitriol) and fail to excrete phosphate. Low calcitriol and high phosphate lead to
hypocalcemia, which stimulates the parathyroid glands to overproduce PTH.
2. A patient with a pituitary tumor presents with galactorrhea, amenorrhea, and visual field
disturbances. Which hormone is most likely being oversecreted?
A. Growth Hormone (GH)
B. Thyroid Stimulating Hormone (TSH)
,C. Adrenocorticotropic Hormone (ACTH)
D. Prolactin
Answer: D
Conceptual Explanation: Hyperprolactinemia causes galactorrhea (milk production) and
inhibits GnRH, leading to amenorrhea. Visual field disturbances (bitemporal hemianopsia)
occur due to the tumor compressing the optic chiasm.
3. Which pathological feature distinguishes Crohn’s disease from Ulcerative Colitis?
A. Transmural inflammation and skip lesions
B. Continuous lesions starting from the rectum
C. Involvement restricted to the mucosal layer only
D. Universal presence of bloody diarrhea
Answer: A
Conceptual Explanation: Crohn’s disease involves all layers of the bowel wall
(transmural) and exhibits skip lesions (patchy areas of inflammation), whereas Ulcerative
Colitis is typically continuous and limited to the mucosa.
4. In the pathogenesis of Type 1 Diabetes Mellitus, what is the primary cause of insulin
deficiency?
A. Amyloid deposition in the Islets of Langerhans
B. Downregulation of insulin receptors on peripheral tissues
, C. Hypersecretion of glucagon from alpha cells inhibiting insulin release
D. T-cell mediated autoimmune destruction of pancreatic beta cells
Answer: D
Conceptual Explanation: Type 1 Diabetes is an autoimmune disorder where CD8+ T-cells
and autoantibodies destroy pancreatic beta cells, leading to an absolute lack of insulin.
5. A patient presents with a ‘moon face,’ buffalo hump, and purple striae. Lab results show
elevated cortisol and low ACTH. What is the most likely diagnosis?
A. Adrenal Adenoma
B. Addison’s Disease
C. Ectopic ACTH Syndrome
D. Cushing’s Disease
Answer: A
Conceptual Explanation: Elevated cortisol with low ACTH indicates a primary adrenal
cause (like an adenoma) where the adrenal gland is autonomously secreting cortisol,
providing negative feedback to the pituitary to lower ACTH.
6. What is the underlying pathophysiology of Myasthenia Gravis?
A. Autoantibodies against acetylcholine receptors at the neuromuscular junction
B. Demyelination of the peripheral nervous system
C. Destruction of dopamine-producing neurons in the substantia nigra
