NR283 EXAM 3 PATHOPHYSIOLOGY
COMPREHENSIVE REVIEW QUESTIONS
AND ANSWERS
1. A patient presents with extreme polyuria, a serum sodium of 152 mEq/L, and a urine
specific gravity of 1.002. Which condition is most likely responsible?
A. Diabetes Insipidus (DI)
B. Diabetes Mellitus Type 1
C. Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
D. Hyperaldosteronism
Answer: A
Conceptual Explanation: Diabetes Insipidus is characterized by a deficiency of ADH or a
lack of response to it, leading to the excretion of large volumes of dilute urine (low specific
gravity) and resulting in hemoconcentration and hypernatremia.
2. Which pathophysiological process occurs in Syndrome of Inappropriate Antidiuretic
Hormone (SIADH)?
A. Sodium wasting due to aldosterone deficiency
B. Hyperglycemia causing osmotic diuresis
,C. Reduced renal perfusion activating the RAAS system
D. Excessive water retention leading to dilutional hyponatremia
Answer: D
Conceptual Explanation: SIADH involves excessive ADH release, which leads to increased
water reabsorption in the collecting ducts, causing fluid volume expansion and a decrease
in serum sodium concentration via dilution.
3. In the development of Type 1 Diabetes Mellitus, which mechanism is primarily responsible
for the destruction of pancreatic beta cells?
A. Autoimmune T-cell mediated destruction
B. Insulin resistance and exhaustion of beta cells
C. Excessive intake of dietary glucose
D. Bacterial infection of the islets of Langerhans
Answer: A
Conceptual Explanation: Type 1 Diabetes is an autoimmune disease where the body’s
own T-cells attack and destroy the insulin-producing beta cells in the pancreas, leading to
absolute insulin deficiency.
4. A patient with Type 2 Diabetes is found to have a high fasting blood glucose despite normal
insulin production early in the disease. What is the hallmark of this condition?
A. Total lack of insulin secretion
, B. Increased sensitivity of GLUT-4 receptors
C. Insulin resistance at the peripheral tissues
D. Excessive glucagon suppression
Answer: C
Conceptual Explanation: Type 2 Diabetes is characterized by insulin resistance, where
cells fail to respond effectively to insulin, often coupled with a relative insulin deficiency
over time.
5. What is the primary cause of Kussmaul respirations in a patient experiencing Diabetic
Ketoacidosis (DKA)?
A. Pulmonary edema due to fluid overload
B. Compensatory hyperventilation to reduce CO2 levels and correct metabolic acidosis
C. Hypoventilation to conserve bicarbonate
D. Brainstem damage from extreme hyperglycemia
Answer: B
Conceptual Explanation: Kussmaul respirations are deep, rapid breaths that serve as a
compensatory mechanism to blow off carbon dioxide, thereby increasing the pH in
response to metabolic acidosis caused by ketone body accumulation.
COMPREHENSIVE REVIEW QUESTIONS
AND ANSWERS
1. A patient presents with extreme polyuria, a serum sodium of 152 mEq/L, and a urine
specific gravity of 1.002. Which condition is most likely responsible?
A. Diabetes Insipidus (DI)
B. Diabetes Mellitus Type 1
C. Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
D. Hyperaldosteronism
Answer: A
Conceptual Explanation: Diabetes Insipidus is characterized by a deficiency of ADH or a
lack of response to it, leading to the excretion of large volumes of dilute urine (low specific
gravity) and resulting in hemoconcentration and hypernatremia.
2. Which pathophysiological process occurs in Syndrome of Inappropriate Antidiuretic
Hormone (SIADH)?
A. Sodium wasting due to aldosterone deficiency
B. Hyperglycemia causing osmotic diuresis
,C. Reduced renal perfusion activating the RAAS system
D. Excessive water retention leading to dilutional hyponatremia
Answer: D
Conceptual Explanation: SIADH involves excessive ADH release, which leads to increased
water reabsorption in the collecting ducts, causing fluid volume expansion and a decrease
in serum sodium concentration via dilution.
3. In the development of Type 1 Diabetes Mellitus, which mechanism is primarily responsible
for the destruction of pancreatic beta cells?
A. Autoimmune T-cell mediated destruction
B. Insulin resistance and exhaustion of beta cells
C. Excessive intake of dietary glucose
D. Bacterial infection of the islets of Langerhans
Answer: A
Conceptual Explanation: Type 1 Diabetes is an autoimmune disease where the body’s
own T-cells attack and destroy the insulin-producing beta cells in the pancreas, leading to
absolute insulin deficiency.
4. A patient with Type 2 Diabetes is found to have a high fasting blood glucose despite normal
insulin production early in the disease. What is the hallmark of this condition?
A. Total lack of insulin secretion
, B. Increased sensitivity of GLUT-4 receptors
C. Insulin resistance at the peripheral tissues
D. Excessive glucagon suppression
Answer: C
Conceptual Explanation: Type 2 Diabetes is characterized by insulin resistance, where
cells fail to respond effectively to insulin, often coupled with a relative insulin deficiency
over time.
5. What is the primary cause of Kussmaul respirations in a patient experiencing Diabetic
Ketoacidosis (DKA)?
A. Pulmonary edema due to fluid overload
B. Compensatory hyperventilation to reduce CO2 levels and correct metabolic acidosis
C. Hypoventilation to conserve bicarbonate
D. Brainstem damage from extreme hyperglycemia
Answer: B
Conceptual Explanation: Kussmaul respirations are deep, rapid breaths that serve as a
compensatory mechanism to blow off carbon dioxide, thereby increasing the pH in
response to metabolic acidosis caused by ketone body accumulation.
