2026/2027 Galen College
Q1. Which hormone is released from the posterior pituitary and
promotes water reabsorption by the kidneys?
A) Growth hormone
B) Cortisol
C) Antidiuretic hormone
D) Thyroid-stimulating hormone
Correct Answer: C) Antidiuretic hormone
Rationale: Antidiuretic hormone promotes water reabsorption in the renal
collecting ducts, helping maintain blood volume and serum osmolality.
Q2. Which finding is most consistent with diabetes insipidus?
A) Polyuria with dilute urine
B) Fluid retention and concentrated urine
C) Hyperglycemia with ketonuria
D) Generalized edema
Correct Answer: A) Polyuria with dilute urine
Rationale: Diabetes insipidus results from inadequate ADH activity or
response, causing excessive production of dilute urine and often intense
thirst.
Q3. Which laboratory pattern is expected in untreated diabetes
insipidus?
A) Low serum sodium and concentrated urine
B) Elevated serum sodium with dilute urine
C) Low serum osmolality with concentrated urine
D) Low urine output with edema
Correct Answer: B) Elevated serum sodium with dilute urine
Rationale: Excessive free-water loss can raise serum sodium and osmolality
while the urine remains inappropriately dilute.
Q4. Which medication is commonly used to treat central diabetes
insipidus?
A) Insulin
B) Hydrocortisone
, C) Spironolactone
D) Desmopressin
Correct Answer: D) Desmopressin
Rationale: Desmopressin is a synthetic analog of ADH and reduces
excessive water loss in central diabetes insipidus.
Q5. Which finding is most concerning for severe hypernatremic
dehydration in diabetes insipidus?
A) Increased urine output with stable mentation
B) Mild thirst
C) Altered mental status and hypotension
D) Peripheral edema
Correct Answer: C) Altered mental status and hypotension
Rationale: Severe free-water loss can produce hypernatremia, intravascular
depletion, neurologic changes, and circulatory instability.
Q6. Which condition results from excessive secretion of antidiuretic
hormone?
A) Diabetes insipidus
B) Syndrome of inappropriate antidiuretic hormone secretion
C) Addison disease
D) Diabetes mellitus
Correct Answer: B) Syndrome of inappropriate antidiuretic hormone secretion
Rationale: SIADH causes excessive water retention because ADH secretion
or activity is inappropriate for the patient's fluid status.
Q7. Which laboratory finding is characteristic of SIADH?
A) Hypernatremia
B) Elevated serum osmolality
C) Hyponatremia with inappropriately concentrated urine
D) Severe hyperglycemia
Correct Answer: C) Hyponatremia with inappropriately concentrated urine
Rationale: Excess ADH causes water retention, diluting serum sodium while
the kidneys continue to produce urine that is more concentrated than
expected.