HSC 4555 Exam 3 V3 | HSC 4555 Pathophysiology 1 | Actual Q&A with
Rationale (HSC4555 Exam 3) | University of Central Florida
1. A patient presents with polyuria, polydipsia, and a urine specific gravity of 1.001. Which
condition is most likely causing these symptoms?
A. Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
B. Diabetes Mellitus Type 2
C. Diabetes Insipidus (DI)
D. Hyperaldosteronism
Answer: C
Explanation: Diabetes Insipidus is characterized by a deficiency of ADH or a decreased
renal response to ADH. This leads to the excretion of large amounts of dilute urine,
resulting in a low specific gravity. The excessive water loss triggers intense thirst, known as
polydipsia.
2. Which of the following electrolyte imbalances is most characteristic of Syndrome of
Inappropriate Antidiuretic Hormone (SIADH)?
A. Hypernatremia
B. Hypokalemia
C. Hyponatremia
D. Hypercalcemia
Answer: C
Explanation: In SIADH, excessive ADH secretion causes the kidneys to reabsorb too much
water. This excess water dilutes the blood, leading to dilutional hyponatremia. The
condition is often associated with ectopic hormone production from tumors, such as small
cell lung cancer.
3. A patient with Type 1 Diabetes Mellitus presents to the ER with Kussmaul respirations and
a fruity breath odor. What is the primary underlying cause of these findings?
A. Metabolic acidosis due to ketone body accumulation
B. Respiratory alkalosis from hyperventilation
C. Lactic acidosis from anaerobic metabolism
D. Hyperglycemic Hyperosmolar Nonketotic Syndrome
Answer: A
,Explanation: Type 1 diabetics lack insulin, which leads to the breakdown of fats for
energy, producing acidic ketones. The resulting metabolic acidosis triggers Kussmaul
respirations as a compensatory mechanism to blow off CO2. The fruity odor is caused by
the presence of acetone, a type of ketone.
4. Which mechanism best describes the development of Type 2 Diabetes Mellitus?
A. Autoimmune destruction of pancreatic beta cells
B. Inability of the alpha cells to produce glucagon
C. Insulin resistance at the peripheral tissues and eventual beta cell exhaustion
D. Acute inflammation of the exocrine pancreas
Answer: C
Explanation: Type 2 Diabetes involves a combination of insulin resistance, where cells fail
to respond to insulin, and a relative lack of insulin production. Over time, the pancreas
becomes unable to compensate for the high glucose levels. This pathophysiology is strongly
linked to obesity and genetics.
5. A patient with Graves’ disease is likely to exhibit which of the following clinical
manifestations?
A. Weight gain and bradycardia
B. Myxedema and dry skin
C. Cold intolerance and lethargy
D. Exophthalmos and heat intolerance
Answer: D
Explanation: Graves’ disease is a form of hyperthyroidism caused by autoantibodies that
stimulate the TSH receptor. The hypermetabolic state leads to heat intolerance and weight
loss despite increased appetite. Exophthalmos, or bulging eyes, is a specific sign caused by
inflammation in the orbital tissues.
6. What is the primary pathophysiology behind Hashimoto thyroiditis?
A. Excessive production of T3 and T4
B. Autoimmune destruction of the thyroid gland
C. Iodine deficiency in the diet
D. A benign tumor secreting TSH
Answer: B
Explanation: Hashimoto thyroiditis is the most common cause of hypothyroidism in
iodine-sufficient areas. It involves the autoimmune destruction of thyroid tissue by
, lymphocytes and antithyroid antibodies. This results in a gradual decline in thyroid
hormone production and an increase in TSH levels.
7. Which clinical finding is most associated with Cushing’s Syndrome?
A. Hypotension and hyperkalemia
B. Weight loss and hypoglycemia
C. Trunkal obesity and ‘moon face’
D. Skin hyperpigmentation and salt craving
Answer: C
Explanation: Cushing’s Syndrome is caused by excessive levels of cortisol in the body. This
leads to characteristic fat redistribution, including trunkal obesity, a buffalo hump, and a
rounded moon face. It also causes thin skin, purple striae, and impaired wound healing.
8. Addison’s disease is characterized by a deficiency of which hormones?
A. Epinephrine and Norepinephrine
B. Cortisol and Aldosterone
C. Insulin and Glucagon
D. Thyroid Stimulating Hormone and Growth Hormone
Answer: B
Explanation: Addison’s disease, or primary adrenocortical insufficiency, involves the
destruction of the adrenal cortex. This results in the loss of both glucocorticoids (cortisol)
and mineralocorticoids (aldosterone). Symptoms include hypotension, hyperkalemia, and
skin hyperpigmentation due to elevated ACTH.
9. Pheochromocytoma is a tumor of the adrenal medulla that causes the hypersecretion of:
A. Cortisol
B. Aldosterone
C. Antidiuretic Hormone
D. Catecholamines (Epinephrine/Norepinephrine)
Answer: D
Explanation: Pheochromocytoma arises from chromaffin cells in the adrenal medulla. The
tumor secretes large amounts of catecholamines, leading to severe hypertension and
tachycardia. Patients often experience the classic triad of diaphoresis, headache, and
palpitations.
Rationale (HSC4555 Exam 3) | University of Central Florida
1. A patient presents with polyuria, polydipsia, and a urine specific gravity of 1.001. Which
condition is most likely causing these symptoms?
A. Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
B. Diabetes Mellitus Type 2
C. Diabetes Insipidus (DI)
D. Hyperaldosteronism
Answer: C
Explanation: Diabetes Insipidus is characterized by a deficiency of ADH or a decreased
renal response to ADH. This leads to the excretion of large amounts of dilute urine,
resulting in a low specific gravity. The excessive water loss triggers intense thirst, known as
polydipsia.
2. Which of the following electrolyte imbalances is most characteristic of Syndrome of
Inappropriate Antidiuretic Hormone (SIADH)?
A. Hypernatremia
B. Hypokalemia
C. Hyponatremia
D. Hypercalcemia
Answer: C
Explanation: In SIADH, excessive ADH secretion causes the kidneys to reabsorb too much
water. This excess water dilutes the blood, leading to dilutional hyponatremia. The
condition is often associated with ectopic hormone production from tumors, such as small
cell lung cancer.
3. A patient with Type 1 Diabetes Mellitus presents to the ER with Kussmaul respirations and
a fruity breath odor. What is the primary underlying cause of these findings?
A. Metabolic acidosis due to ketone body accumulation
B. Respiratory alkalosis from hyperventilation
C. Lactic acidosis from anaerobic metabolism
D. Hyperglycemic Hyperosmolar Nonketotic Syndrome
Answer: A
,Explanation: Type 1 diabetics lack insulin, which leads to the breakdown of fats for
energy, producing acidic ketones. The resulting metabolic acidosis triggers Kussmaul
respirations as a compensatory mechanism to blow off CO2. The fruity odor is caused by
the presence of acetone, a type of ketone.
4. Which mechanism best describes the development of Type 2 Diabetes Mellitus?
A. Autoimmune destruction of pancreatic beta cells
B. Inability of the alpha cells to produce glucagon
C. Insulin resistance at the peripheral tissues and eventual beta cell exhaustion
D. Acute inflammation of the exocrine pancreas
Answer: C
Explanation: Type 2 Diabetes involves a combination of insulin resistance, where cells fail
to respond to insulin, and a relative lack of insulin production. Over time, the pancreas
becomes unable to compensate for the high glucose levels. This pathophysiology is strongly
linked to obesity and genetics.
5. A patient with Graves’ disease is likely to exhibit which of the following clinical
manifestations?
A. Weight gain and bradycardia
B. Myxedema and dry skin
C. Cold intolerance and lethargy
D. Exophthalmos and heat intolerance
Answer: D
Explanation: Graves’ disease is a form of hyperthyroidism caused by autoantibodies that
stimulate the TSH receptor. The hypermetabolic state leads to heat intolerance and weight
loss despite increased appetite. Exophthalmos, or bulging eyes, is a specific sign caused by
inflammation in the orbital tissues.
6. What is the primary pathophysiology behind Hashimoto thyroiditis?
A. Excessive production of T3 and T4
B. Autoimmune destruction of the thyroid gland
C. Iodine deficiency in the diet
D. A benign tumor secreting TSH
Answer: B
Explanation: Hashimoto thyroiditis is the most common cause of hypothyroidism in
iodine-sufficient areas. It involves the autoimmune destruction of thyroid tissue by
, lymphocytes and antithyroid antibodies. This results in a gradual decline in thyroid
hormone production and an increase in TSH levels.
7. Which clinical finding is most associated with Cushing’s Syndrome?
A. Hypotension and hyperkalemia
B. Weight loss and hypoglycemia
C. Trunkal obesity and ‘moon face’
D. Skin hyperpigmentation and salt craving
Answer: C
Explanation: Cushing’s Syndrome is caused by excessive levels of cortisol in the body. This
leads to characteristic fat redistribution, including trunkal obesity, a buffalo hump, and a
rounded moon face. It also causes thin skin, purple striae, and impaired wound healing.
8. Addison’s disease is characterized by a deficiency of which hormones?
A. Epinephrine and Norepinephrine
B. Cortisol and Aldosterone
C. Insulin and Glucagon
D. Thyroid Stimulating Hormone and Growth Hormone
Answer: B
Explanation: Addison’s disease, or primary adrenocortical insufficiency, involves the
destruction of the adrenal cortex. This results in the loss of both glucocorticoids (cortisol)
and mineralocorticoids (aldosterone). Symptoms include hypotension, hyperkalemia, and
skin hyperpigmentation due to elevated ACTH.
9. Pheochromocytoma is a tumor of the adrenal medulla that causes the hypersecretion of:
A. Cortisol
B. Aldosterone
C. Antidiuretic Hormone
D. Catecholamines (Epinephrine/Norepinephrine)
Answer: D
Explanation: Pheochromocytoma arises from chromaffin cells in the adrenal medulla. The
tumor secretes large amounts of catecholamines, leading to severe hypertension and
tachycardia. Patients often experience the classic triad of diaphoresis, headache, and
palpitations.
