,NURS 231 / BIOD 331 Pathophysiology Module 9 Exam |
1. Which endocrine disorder is characterized by chronic adrenal insufficiency leading to decreased
cortisol and aldosterone production?
A) Cushing syndrome
B) Addison's disease
C) Graves' disease
D) Pheochromocytoma
Correct Answer: Addison's disease
Rationale: Addison's disease is primary adrenal insufficiency resulting from autoimmune destruction
or other damage to the adrenal cortex, leading to deficient cortisol and aldosterone. Cushing
syndrome involves excess cortisol. Graves' disease is thyroid hyperfunction. Pheochromocytoma is a
catecholamine-secreting tumor.
2. A patient with Addison's disease would most likely exhibit which of the following laboratory
findings?
A) Hyperglycemia and hypernatremia
B) Hypoglycemia and hyponatremia
C) Hyperkalemia and hyperglycemia
D) Hypokalemia and hypernatremia
Correct Answer: Hypoglycemia and hyponatremia
Rationale: Aldosterone deficiency in Addison's causes sodium wasting (hyponatremia) and potassium
retention (hyperkalemia). Cortisol deficiency reduces gluconeogenesis, leading to hypoglycemia.
Hyperglycemia and hypernatremia are incorrect as they reflect glucocorticoid excess. Hypokalemia is
associated with hyperaldosteronism, not deficiency.
3. Which of the following is a classic clinical manifestation of Cushing syndrome?
A) Hyperpigmentation of the skin
,B) Moon facies and central obesity
C) Orthostatic hypotension
D) Weight loss and diarrhea
Correct Answer: Moon facies and central obesity
Rationale: Cushing syndrome results from chronic glucocorticoid excess, producing characteristic
features including moon facies, central obesity, dorsocervical fat pad (buffalo hump), and striae.
Hyperpigmentation is seen in Addison's (due to elevated ACTH). Hypotension and weight loss are not
typical of Cushing syndrome.
4. What is the most common cause of Cushing syndrome?
A) Pituitary adenoma secreting excessive ACTH
B) Adrenal adenoma secreting cortisol
C) Ectopic ACTH production from small cell lung cancer
D) Chronic exogenous glucocorticoid administration
Correct Answer: Chronic exogenous glucocorticoid administration
Rationale: Iatrogenic Cushing syndrome from prolonged glucocorticoid therapy is the most common
cause overall. Among endogenous causes, pituitary adenoma (Cushing disease) is most frequent.
Adrenal adenoma and ectopic ACTH are less common causes.
5. Primary hyperaldosteronism (Conn syndrome) is characterized by which of the following laboratory
findings?
A) Hypokalemia and metabolic alkalosis
B) Hyperkalemia and metabolic acidosis
C) Hyponatremia and hyperkalemia
D) Hypernatremia and metabolic acidosis
Correct Answer: Hypokalemia and metabolic alkalosis
, Rationale: Excess aldosterone increases sodium reabsorption and potassium/hydrogen ion excretion,
resulting in hypokalemia and metabolic alkalosis. Hyperkalemia and acidosis are seen in aldosterone
deficiency (Addison's). Hyponatremia is not characteristic of primary hyperaldosteronism.
6. Graves' disease is an autoimmune disorder caused by antibodies that:
A) Destroy thyroid follicular cells
B) Block TSH receptor activity
C) Stimulate the TSH receptor, causing thyroid hyperfunction
D) Inhibit thyroid peroxidase enzyme
Correct Answer: Stimulate the TSH receptor, causing thyroid hyperfunction
Rationale: In Graves' disease, TSH-receptor antibodies (TRAb) mimic TSH and continuously stimulate
the thyroid gland, leading to hyperthyroidism. The antibodies are stimulatory, not destructive or
blocking. Thyroid peroxidase inhibition is seen in Hashimoto's thyroiditis.
7. Which of the following clinical features is most consistent with hyperthyroidism?
A) Weight gain and cold intolerance
B) Bradycardia and constipation
C) Tachycardia and heat intolerance
D) Lethargy and dry skin
Correct Answer: Tachycardia and heat intolerance
Rationale: Hyperthyroidism increases metabolic rate, causing tachycardia, heat intolerance, weight
loss, and warm moist skin. Weight gain, cold intolerance, bradycardia, constipation, lethargy, and dry
skin are characteristic of hypothyroidism.
8. Hashimoto's thyroiditis is the most common cause of:
A) Hyperthyroidism in young adults
1. Which endocrine disorder is characterized by chronic adrenal insufficiency leading to decreased
cortisol and aldosterone production?
A) Cushing syndrome
B) Addison's disease
C) Graves' disease
D) Pheochromocytoma
Correct Answer: Addison's disease
Rationale: Addison's disease is primary adrenal insufficiency resulting from autoimmune destruction
or other damage to the adrenal cortex, leading to deficient cortisol and aldosterone. Cushing
syndrome involves excess cortisol. Graves' disease is thyroid hyperfunction. Pheochromocytoma is a
catecholamine-secreting tumor.
2. A patient with Addison's disease would most likely exhibit which of the following laboratory
findings?
A) Hyperglycemia and hypernatremia
B) Hypoglycemia and hyponatremia
C) Hyperkalemia and hyperglycemia
D) Hypokalemia and hypernatremia
Correct Answer: Hypoglycemia and hyponatremia
Rationale: Aldosterone deficiency in Addison's causes sodium wasting (hyponatremia) and potassium
retention (hyperkalemia). Cortisol deficiency reduces gluconeogenesis, leading to hypoglycemia.
Hyperglycemia and hypernatremia are incorrect as they reflect glucocorticoid excess. Hypokalemia is
associated with hyperaldosteronism, not deficiency.
3. Which of the following is a classic clinical manifestation of Cushing syndrome?
A) Hyperpigmentation of the skin
,B) Moon facies and central obesity
C) Orthostatic hypotension
D) Weight loss and diarrhea
Correct Answer: Moon facies and central obesity
Rationale: Cushing syndrome results from chronic glucocorticoid excess, producing characteristic
features including moon facies, central obesity, dorsocervical fat pad (buffalo hump), and striae.
Hyperpigmentation is seen in Addison's (due to elevated ACTH). Hypotension and weight loss are not
typical of Cushing syndrome.
4. What is the most common cause of Cushing syndrome?
A) Pituitary adenoma secreting excessive ACTH
B) Adrenal adenoma secreting cortisol
C) Ectopic ACTH production from small cell lung cancer
D) Chronic exogenous glucocorticoid administration
Correct Answer: Chronic exogenous glucocorticoid administration
Rationale: Iatrogenic Cushing syndrome from prolonged glucocorticoid therapy is the most common
cause overall. Among endogenous causes, pituitary adenoma (Cushing disease) is most frequent.
Adrenal adenoma and ectopic ACTH are less common causes.
5. Primary hyperaldosteronism (Conn syndrome) is characterized by which of the following laboratory
findings?
A) Hypokalemia and metabolic alkalosis
B) Hyperkalemia and metabolic acidosis
C) Hyponatremia and hyperkalemia
D) Hypernatremia and metabolic acidosis
Correct Answer: Hypokalemia and metabolic alkalosis
, Rationale: Excess aldosterone increases sodium reabsorption and potassium/hydrogen ion excretion,
resulting in hypokalemia and metabolic alkalosis. Hyperkalemia and acidosis are seen in aldosterone
deficiency (Addison's). Hyponatremia is not characteristic of primary hyperaldosteronism.
6. Graves' disease is an autoimmune disorder caused by antibodies that:
A) Destroy thyroid follicular cells
B) Block TSH receptor activity
C) Stimulate the TSH receptor, causing thyroid hyperfunction
D) Inhibit thyroid peroxidase enzyme
Correct Answer: Stimulate the TSH receptor, causing thyroid hyperfunction
Rationale: In Graves' disease, TSH-receptor antibodies (TRAb) mimic TSH and continuously stimulate
the thyroid gland, leading to hyperthyroidism. The antibodies are stimulatory, not destructive or
blocking. Thyroid peroxidase inhibition is seen in Hashimoto's thyroiditis.
7. Which of the following clinical features is most consistent with hyperthyroidism?
A) Weight gain and cold intolerance
B) Bradycardia and constipation
C) Tachycardia and heat intolerance
D) Lethargy and dry skin
Correct Answer: Tachycardia and heat intolerance
Rationale: Hyperthyroidism increases metabolic rate, causing tachycardia, heat intolerance, weight
loss, and warm moist skin. Weight gain, cold intolerance, bradycardia, constipation, lethargy, and dry
skin are characteristic of hypothyroidism.
8. Hashimoto's thyroiditis is the most common cause of:
A) Hyperthyroidism in young adults
