NUR 546/NUR546 Exam 3 V3 | Advanced
Pathophysiology Q&A with Rationale |
William Paterson University
1. A patient presents with excessive thirst, polyuria, and a very low urine specific gravity.
Which condition is most likely related to a deficiency in Antidiuretic Hormone (ADH)?
A. Diabetes Insipidus
B. SIADH
C. Diabetes Mellitus Type 1
D. Cushing Syndrome
Correct Answer: A
Expert Explanation: Diabetes Insipidus (DI) is characterized by an insufficiency of ADH or
a lack of response to it. This leads to the inability of the kidneys to concentrate urine,
resulting in large volumes of dilute urine. Patients typically present with extreme thirst and
hypernatremia due to water loss.
2. Which of the following laboratory findings is most characteristic of Syndrome of
Inappropriate Antidiuretic Hormone (SIADH)?
A. Urine specific gravity of 1.002
B. Serum osmolality of 310 mOsm/kg
C. Serum sodium of 125 mEq/L
,D. Blood glucose of 250 mg/dL
Correct Answer: C
Expert Explanation: SIADH involves the excessive release of ADH, which causes the body
to retain too much water. This water retention leads to dilutional hyponatremia, where the
serum sodium levels drop significantly. This condition is often associated with certain
cancers or central nervous system disorders.
3. A patient with Grave’s disease is likely to exhibit which of the following pathophysiological
manifestations?
A. Weight gain and lethargy
B. Exophthalmos and tachycardia
C. Bradycardia and cold intolerance
D. Hypocalcemia and tetany
Correct Answer: B
Expert Explanation: Grave’s disease is an autoimmune disorder that causes
hyperthyroidism through Type II hypersensitivity. The autoantibodies stimulate the TSH
receptors, leading to excessive thyroid hormone production. Common clinical features
include bulging eyes, heat intolerance, and an increased metabolic rate.
4. What is the primary underlying cause of Type 1 Diabetes Mellitus?
A. Insulin resistance in peripheral tissues
, B. Excessive glucagon secretion from alpha cells
C. Autoimmune destruction of pancreatic beta cells
D. Chronic obesity and physical inactivity
Correct Answer: C
Expert Explanation: Type 1 Diabetes Mellitus is primarily an autoimmune condition
where T-cells attack and destroy the insulin-producing beta cells in the pancreas. This
results in an absolute insulin deficiency, requiring exogenous insulin for survival. It is
distinct from Type 2 diabetes, which is characterized by insulin resistance rather than total
destruction.
5. Which clinical manifestation is a hallmark of Cushing Syndrome due to chronic cortisol
excess?
A. Truncal obesity and buffalo hump
B. Bronze-colored skin
C. Severe hypotension
D. Weight loss and muscle wasting
Correct Answer: A
Expert Explanation: Cushing Syndrome is caused by prolonged exposure to high levels of
glucocorticoids like cortisol. This excess hormone leads to abnormal fat distribution,
Pathophysiology Q&A with Rationale |
William Paterson University
1. A patient presents with excessive thirst, polyuria, and a very low urine specific gravity.
Which condition is most likely related to a deficiency in Antidiuretic Hormone (ADH)?
A. Diabetes Insipidus
B. SIADH
C. Diabetes Mellitus Type 1
D. Cushing Syndrome
Correct Answer: A
Expert Explanation: Diabetes Insipidus (DI) is characterized by an insufficiency of ADH or
a lack of response to it. This leads to the inability of the kidneys to concentrate urine,
resulting in large volumes of dilute urine. Patients typically present with extreme thirst and
hypernatremia due to water loss.
2. Which of the following laboratory findings is most characteristic of Syndrome of
Inappropriate Antidiuretic Hormone (SIADH)?
A. Urine specific gravity of 1.002
B. Serum osmolality of 310 mOsm/kg
C. Serum sodium of 125 mEq/L
,D. Blood glucose of 250 mg/dL
Correct Answer: C
Expert Explanation: SIADH involves the excessive release of ADH, which causes the body
to retain too much water. This water retention leads to dilutional hyponatremia, where the
serum sodium levels drop significantly. This condition is often associated with certain
cancers or central nervous system disorders.
3. A patient with Grave’s disease is likely to exhibit which of the following pathophysiological
manifestations?
A. Weight gain and lethargy
B. Exophthalmos and tachycardia
C. Bradycardia and cold intolerance
D. Hypocalcemia and tetany
Correct Answer: B
Expert Explanation: Grave’s disease is an autoimmune disorder that causes
hyperthyroidism through Type II hypersensitivity. The autoantibodies stimulate the TSH
receptors, leading to excessive thyroid hormone production. Common clinical features
include bulging eyes, heat intolerance, and an increased metabolic rate.
4. What is the primary underlying cause of Type 1 Diabetes Mellitus?
A. Insulin resistance in peripheral tissues
, B. Excessive glucagon secretion from alpha cells
C. Autoimmune destruction of pancreatic beta cells
D. Chronic obesity and physical inactivity
Correct Answer: C
Expert Explanation: Type 1 Diabetes Mellitus is primarily an autoimmune condition
where T-cells attack and destroy the insulin-producing beta cells in the pancreas. This
results in an absolute insulin deficiency, requiring exogenous insulin for survival. It is
distinct from Type 2 diabetes, which is characterized by insulin resistance rather than total
destruction.
5. Which clinical manifestation is a hallmark of Cushing Syndrome due to chronic cortisol
excess?
A. Truncal obesity and buffalo hump
B. Bronze-colored skin
C. Severe hypotension
D. Weight loss and muscle wasting
Correct Answer: A
Expert Explanation: Cushing Syndrome is caused by prolonged exposure to high levels of
glucocorticoids like cortisol. This excess hormone leads to abnormal fat distribution,
