ADULT CCRN CERTIFICATION
MODULE 9
ENDOCRINE
4 PRACTICE TESTS
2024
1. A 45-year-old male with a history of type 1 diabetes mellitus is brought to the emergency
department with altered mental status, nausea, vomiting, and abdominal pain. His blood glucose
level is 450 mg/dL and his urine test shows positive for ketones. He is diagnosed with diabetic
ketoacidosis (DKA) and started on intravenous fluids and insulin infusion. Which of the following
electrolyte imbalances is most likely to occur in this patient?
A) Hyperkalemia
B) Hypokalemia
C) Hypercalcemia
D) Hypocalcemia
Answer: B) Hypokalemia
Rationale: DKA is a state of insulin deficiency that leads to increased breakdown of fat and
protein, resulting in the production of ketone bodies that cause metabolic acidosis. Insulin also
facilitates the uptake of potassium into cells, so insulin deficiency causes potassium to shift out of
cells and into the extracellular fluid. This leads to hyperkalemia initially, but as the patient receives
insulin therapy, potassium moves back into cells and the serum potassium level drops. In addition,
the patient may lose potassium through urine due to osmotic diuresis and vomiting. Therefore,
hypokalemia is a common complication of DKA that requires careful monitoring and replacement.
2. A 60-year-old female with a history of type 2 diabetes mellitus and hypertension presents to the
clinic with polyuria, polydipsia, and blurred vision. Her blood glucose level is 800 mg/dL and her
serum osmolality is 350 mOsm/kg. She is diagnosed with hyperglycemic hyperosmolar state
(HHS) and admitted to the intensive care unit for fluid resuscitation and insulin therapy. Which of
the following factors is most likely to have contributed to the development of HHS in this patient?
A) Infection
B) Medication noncompliance
C) Renal insufficiency
,D) All of the above
Answer: D) All of the above
Rationale: HHS is a life-threatening complication of type 2 diabetes mellitus that occurs when
there is a relative or absolute deficiency of insulin combined with an increase in counterregulatory
hormones (such as glucagon, cortisol, and catecholamines) that stimulate glucose production and
impair glucose utilization. This leads to severe hyperglycemia and osmotic diuresis, resulting in
dehydration, electrolyte imbalance, and hyperosmolality. HHS can be triggered by various factors
that increase the demand for insulin or impair its action, such as infection, medication
noncompliance, renal insufficiency, acute illness, or stress.
3. A 25-year-old female with a history of bipolar disorder is admitted to the psychiatric ward for a
manic episode. She has been drinking excessive amounts of water and urinating frequently. Her
serum sodium level is 125 mEq/L and her urine specific gravity is 1.005. She is diagnosed with
diabetes insipidus (DI) and started on desmopressin acetate (DDAVP) nasal spray. Which of the
following types of DI is most likely to affect this patient?
A) Central DI
B) Nephrogenic DI
C) Dipsogenic DI
D) Gestational DI
Answer: C) Dipsogenic DI
Rationale: DI is a disorder characterized by the inability to concentrate urine due to a deficiency or
resistance to antidiuretic hormone (ADH), also known as vasopressin. ADH is produced by the
hypothalamus and stored and released by the posterior pituitary gland. It acts on the kidneys to
reabsorb water and maintain fluid balance. There are four types of DI: central DI, nephrogenic DI,
dipsogenic DI, and gestational DI. Central DI occurs when there is a lack of ADH production or
release due to damage or dysfunction of the hypothalamus or pituitary gland. Nephrogenic DI
occurs when there is a lack of response to ADH by the renal tubules due to genetic mutations or
medications that impair ADH action. Dipsogenic DI occurs when there is an excessive intake of
fluids due to damage or dysfunction of the thirst center in the hypothalamus or psychiatric
disorders that cause compulsive drinking behavior. Gestational DI occurs when there is an
increased metabolism or clearance of ADH by placental enzymes during pregnancy. In this case,
the patient has dipsogenic DI due to her bipolar disorder.
4. A 50-year-old male with a history of lung cancer is admitted to the hospital for palliative care.
He has been complaining of headache, nausea, weakness, and confusion. His serum sodium level is
110 mEq/L and his urine osmolality is 600 mOsm/kg. He is diagnosed with syndrome of
inappropriate antidiuretic hormone secretion (SIADH) and started on fluid restriction and
hypertonic saline infusion. Which of the following mechanisms is most likely to cause SIADH in
this patient?
A) Ectopic production of ADH by the tumor cells
B) Increased sensitivity of the renal tubules to ADH
C) Decreased excretion of ADH by the kidneys
D) Increased stimulation of the osmoreceptors by the tumor cells
Answer: A) Ectopic production of ADH by the tumor cells
Rationale: SIADH is a disorder characterized by the excessive secretion or action of ADH, leading
to water retention, dilutional hyponatremia, and urine concentration. SIADH can be caused by
various factors that increase the production or release of ADH, such as tumors, infections,
medications, or central nervous system disorders. In this case, the patient has SIADH due to
ectopic production of ADH by the lung cancer cells, which is a common cause of SIADH in
malignancy.
,5. A 35-year-old female with a history of type 1 diabetes mellitus is scheduled for a thyroidectomy
due to a large goiter. She is instructed to take her regular dose of insulin on the morning of the
surgery. However, she forgets to do so and arrives at the hospital with a blood glucose level of 250
mg/dL. She is given a bolus of regular insulin intravenously and taken to the operating room.
During the surgery, she develops tremors, sweating, palpitations, and anxiety. She is diagnosed
with hypoglycemia and given 50% dextrose solution intravenously. Which of the following factors
is most likely to have caused hypoglycemia in this patient?
A) Stress-induced hyperglycemia
B) Insulin overdose
C) Fasting state
D) Somogyi effect
Answer: C) Fasting state
Rationale: Hypoglycemia is a condition characterized by a low blood glucose level (<70 mg/dL),
which can cause neuroglycopenic symptoms (such as confusion, seizures, coma) or adrenergic
symptoms (such as tremors, sweating, palpitations, anxiety). Hypoglycemia can be caused by
various factors that create an imbalance between glucose intake and utilization, such as insulin
overdose, fasting state, exercise, alcohol consumption, or medications that lower blood glucose. In
this case, the patient has hypoglycemia due to fasting state, which reduces the availability of
glucose for metabolism. She also received a bolus of insulin without eating anything, which further
lowers her blood glucose level.
6. A 40-year-old male with a history of type 2 diabetes mellitus and obesity is prescribed
metformin and lifestyle modifications by his primary care provider. He is advised to follow a low-
carbohydrate diet and exercise regularly. He returns to the clinic after three months for a follow-up
visit. His blood glucose level is 150 mg/dL and his hemoglobin A1c level is 7%. He reports that he
has lost 10 pounds and feels more energetic. He asks if he can stop taking metformin since his
blood glucose level has improved. Which of the following responses is most appropriate for the
provider to give?
A) "Yes, you can stop taking metformin since your blood glucose level is normal now."
B) "No, you need to continue taking metformin since your blood glucose level is still high."
C) "Yes, you can stop taking metformin but you need to monitor your blood glucose level closely."
D) "No, you need to continue taking metformin and maintain your lifestyle modifications."
Answer: D) No, you need to continue taking metformin and maintain your lifestyle modifications.
Rationale: Metformin is an oral antidiabetic medication that belongs to the biguanide class. It
works by decreasing hepatic glucose production, increasing peripheral glucose uptake, and
reducing intestinal glucose absorption. Metformin is usually the first-line therapy for type 2
diabetes mellitus because it has a low risk of hypoglycemia and weight gain. Metformin also has
beneficial effects on cardiovascular outcomes and mortality in patients with type 2 diabetes
mellitus. Therefore, metformin should not be discontinued unless there are contraindications or
intolerable side effects. Lifestyle modifications such as diet and exercise are also important for
managing type 2 diabetes mellitus because they can improve insulin sensitivity and lower blood
glucose levels.
Which of the following conditions is characterized by an abnormally low level of blood glucose?
a) Diabetic ketoacidosis
b) Hyperglycemic hyperosmolar state
c) Hypoglycemia
d) Diabetes insipidus
Answer: c) Hypoglycemia
Rationale: Hypoglycemia is defined as a blood glucose level below 70 mg/dL. It can result from
, excessive insulin, decreased caloric intake, or increased physical activity.
What is the primary ketone body that accumulates in diabetic ketoacidosis?
a) Acetoacetate
b) Beta-hydroxybutyrate
c) Acetone
d) Isopropanol
Answer: b) Beta-hydroxybutyrate
Rationale: Diabetic ketoacidosis is characterized by the accumulation of ketone bodies, including
acetoacetate and beta-hydroxybutyrate, leading to metabolic acidosis.
Which of the following conditions is characterized by severe hyperglycemia, hyperosmolarity, and
dehydration without significant ketoacidosis?
a) Diabetic ketoacidosis
b) Hyperglycemic hyperosmolar state
c) Hypoglycemia
d) Diabetes insipidus
Answer: b) Hyperglycemic hyperosmolar state
Rationale: Hyperglycemic hyperosmolar state is a life-threatening complication of diabetes
mellitus characterized by severe hyperglycemia, hyperosmolarity, and dehydration without
significant ketoacidosis.
What is the primary treatment for hypoglycemia in conscious patients?
a) Glucagon injection
b) Intravenous dextrose
c) Oral glucose
d) Insulin infusion
Answer: c) Oral glucose
Rationale: The primary treatment for hypoglycemia in conscious patients is the administration of
oral glucose, such as glucose tablets or juice.
Which of the following hormones is responsible for regulating water balance in the body?
a) Insulin
b) Antidiuretic hormone (ADH)
c) Glucagon
d) Growth hormone
Answer: b) Antidiuretic hormone (ADH)
Rationale: Antidiuretic hormone (ADH), also known as vasopressin, regulates water balance by
controlling the reabsorption of water in the kidneys.
What is the classic triad of symptoms associated with diabetes insipidus?
a) Polyuria, polydipsia, and dehydration
b) Hyperglycemia, ketosis, and acidosis
c) Hypotension, tachycardia, and diaphoresis
d) Bradycardia, hypothermia, and constipation
Answer: a) Polyuria, polydipsia, and dehydration
Rationale: Diabetes insipidus is characterized by excessive urination (polyuria), excessive thirst
(polydipsia), and dehydration due to the inability to concentrate urine.
Which of the following laboratory findings is consistent with syndrome of inappropriate
antidiuretic hormone (SIADH)?
MODULE 9
ENDOCRINE
4 PRACTICE TESTS
2024
1. A 45-year-old male with a history of type 1 diabetes mellitus is brought to the emergency
department with altered mental status, nausea, vomiting, and abdominal pain. His blood glucose
level is 450 mg/dL and his urine test shows positive for ketones. He is diagnosed with diabetic
ketoacidosis (DKA) and started on intravenous fluids and insulin infusion. Which of the following
electrolyte imbalances is most likely to occur in this patient?
A) Hyperkalemia
B) Hypokalemia
C) Hypercalcemia
D) Hypocalcemia
Answer: B) Hypokalemia
Rationale: DKA is a state of insulin deficiency that leads to increased breakdown of fat and
protein, resulting in the production of ketone bodies that cause metabolic acidosis. Insulin also
facilitates the uptake of potassium into cells, so insulin deficiency causes potassium to shift out of
cells and into the extracellular fluid. This leads to hyperkalemia initially, but as the patient receives
insulin therapy, potassium moves back into cells and the serum potassium level drops. In addition,
the patient may lose potassium through urine due to osmotic diuresis and vomiting. Therefore,
hypokalemia is a common complication of DKA that requires careful monitoring and replacement.
2. A 60-year-old female with a history of type 2 diabetes mellitus and hypertension presents to the
clinic with polyuria, polydipsia, and blurred vision. Her blood glucose level is 800 mg/dL and her
serum osmolality is 350 mOsm/kg. She is diagnosed with hyperglycemic hyperosmolar state
(HHS) and admitted to the intensive care unit for fluid resuscitation and insulin therapy. Which of
the following factors is most likely to have contributed to the development of HHS in this patient?
A) Infection
B) Medication noncompliance
C) Renal insufficiency
,D) All of the above
Answer: D) All of the above
Rationale: HHS is a life-threatening complication of type 2 diabetes mellitus that occurs when
there is a relative or absolute deficiency of insulin combined with an increase in counterregulatory
hormones (such as glucagon, cortisol, and catecholamines) that stimulate glucose production and
impair glucose utilization. This leads to severe hyperglycemia and osmotic diuresis, resulting in
dehydration, electrolyte imbalance, and hyperosmolality. HHS can be triggered by various factors
that increase the demand for insulin or impair its action, such as infection, medication
noncompliance, renal insufficiency, acute illness, or stress.
3. A 25-year-old female with a history of bipolar disorder is admitted to the psychiatric ward for a
manic episode. She has been drinking excessive amounts of water and urinating frequently. Her
serum sodium level is 125 mEq/L and her urine specific gravity is 1.005. She is diagnosed with
diabetes insipidus (DI) and started on desmopressin acetate (DDAVP) nasal spray. Which of the
following types of DI is most likely to affect this patient?
A) Central DI
B) Nephrogenic DI
C) Dipsogenic DI
D) Gestational DI
Answer: C) Dipsogenic DI
Rationale: DI is a disorder characterized by the inability to concentrate urine due to a deficiency or
resistance to antidiuretic hormone (ADH), also known as vasopressin. ADH is produced by the
hypothalamus and stored and released by the posterior pituitary gland. It acts on the kidneys to
reabsorb water and maintain fluid balance. There are four types of DI: central DI, nephrogenic DI,
dipsogenic DI, and gestational DI. Central DI occurs when there is a lack of ADH production or
release due to damage or dysfunction of the hypothalamus or pituitary gland. Nephrogenic DI
occurs when there is a lack of response to ADH by the renal tubules due to genetic mutations or
medications that impair ADH action. Dipsogenic DI occurs when there is an excessive intake of
fluids due to damage or dysfunction of the thirst center in the hypothalamus or psychiatric
disorders that cause compulsive drinking behavior. Gestational DI occurs when there is an
increased metabolism or clearance of ADH by placental enzymes during pregnancy. In this case,
the patient has dipsogenic DI due to her bipolar disorder.
4. A 50-year-old male with a history of lung cancer is admitted to the hospital for palliative care.
He has been complaining of headache, nausea, weakness, and confusion. His serum sodium level is
110 mEq/L and his urine osmolality is 600 mOsm/kg. He is diagnosed with syndrome of
inappropriate antidiuretic hormone secretion (SIADH) and started on fluid restriction and
hypertonic saline infusion. Which of the following mechanisms is most likely to cause SIADH in
this patient?
A) Ectopic production of ADH by the tumor cells
B) Increased sensitivity of the renal tubules to ADH
C) Decreased excretion of ADH by the kidneys
D) Increased stimulation of the osmoreceptors by the tumor cells
Answer: A) Ectopic production of ADH by the tumor cells
Rationale: SIADH is a disorder characterized by the excessive secretion or action of ADH, leading
to water retention, dilutional hyponatremia, and urine concentration. SIADH can be caused by
various factors that increase the production or release of ADH, such as tumors, infections,
medications, or central nervous system disorders. In this case, the patient has SIADH due to
ectopic production of ADH by the lung cancer cells, which is a common cause of SIADH in
malignancy.
,5. A 35-year-old female with a history of type 1 diabetes mellitus is scheduled for a thyroidectomy
due to a large goiter. She is instructed to take her regular dose of insulin on the morning of the
surgery. However, she forgets to do so and arrives at the hospital with a blood glucose level of 250
mg/dL. She is given a bolus of regular insulin intravenously and taken to the operating room.
During the surgery, she develops tremors, sweating, palpitations, and anxiety. She is diagnosed
with hypoglycemia and given 50% dextrose solution intravenously. Which of the following factors
is most likely to have caused hypoglycemia in this patient?
A) Stress-induced hyperglycemia
B) Insulin overdose
C) Fasting state
D) Somogyi effect
Answer: C) Fasting state
Rationale: Hypoglycemia is a condition characterized by a low blood glucose level (<70 mg/dL),
which can cause neuroglycopenic symptoms (such as confusion, seizures, coma) or adrenergic
symptoms (such as tremors, sweating, palpitations, anxiety). Hypoglycemia can be caused by
various factors that create an imbalance between glucose intake and utilization, such as insulin
overdose, fasting state, exercise, alcohol consumption, or medications that lower blood glucose. In
this case, the patient has hypoglycemia due to fasting state, which reduces the availability of
glucose for metabolism. She also received a bolus of insulin without eating anything, which further
lowers her blood glucose level.
6. A 40-year-old male with a history of type 2 diabetes mellitus and obesity is prescribed
metformin and lifestyle modifications by his primary care provider. He is advised to follow a low-
carbohydrate diet and exercise regularly. He returns to the clinic after three months for a follow-up
visit. His blood glucose level is 150 mg/dL and his hemoglobin A1c level is 7%. He reports that he
has lost 10 pounds and feels more energetic. He asks if he can stop taking metformin since his
blood glucose level has improved. Which of the following responses is most appropriate for the
provider to give?
A) "Yes, you can stop taking metformin since your blood glucose level is normal now."
B) "No, you need to continue taking metformin since your blood glucose level is still high."
C) "Yes, you can stop taking metformin but you need to monitor your blood glucose level closely."
D) "No, you need to continue taking metformin and maintain your lifestyle modifications."
Answer: D) No, you need to continue taking metformin and maintain your lifestyle modifications.
Rationale: Metformin is an oral antidiabetic medication that belongs to the biguanide class. It
works by decreasing hepatic glucose production, increasing peripheral glucose uptake, and
reducing intestinal glucose absorption. Metformin is usually the first-line therapy for type 2
diabetes mellitus because it has a low risk of hypoglycemia and weight gain. Metformin also has
beneficial effects on cardiovascular outcomes and mortality in patients with type 2 diabetes
mellitus. Therefore, metformin should not be discontinued unless there are contraindications or
intolerable side effects. Lifestyle modifications such as diet and exercise are also important for
managing type 2 diabetes mellitus because they can improve insulin sensitivity and lower blood
glucose levels.
Which of the following conditions is characterized by an abnormally low level of blood glucose?
a) Diabetic ketoacidosis
b) Hyperglycemic hyperosmolar state
c) Hypoglycemia
d) Diabetes insipidus
Answer: c) Hypoglycemia
Rationale: Hypoglycemia is defined as a blood glucose level below 70 mg/dL. It can result from
, excessive insulin, decreased caloric intake, or increased physical activity.
What is the primary ketone body that accumulates in diabetic ketoacidosis?
a) Acetoacetate
b) Beta-hydroxybutyrate
c) Acetone
d) Isopropanol
Answer: b) Beta-hydroxybutyrate
Rationale: Diabetic ketoacidosis is characterized by the accumulation of ketone bodies, including
acetoacetate and beta-hydroxybutyrate, leading to metabolic acidosis.
Which of the following conditions is characterized by severe hyperglycemia, hyperosmolarity, and
dehydration without significant ketoacidosis?
a) Diabetic ketoacidosis
b) Hyperglycemic hyperosmolar state
c) Hypoglycemia
d) Diabetes insipidus
Answer: b) Hyperglycemic hyperosmolar state
Rationale: Hyperglycemic hyperosmolar state is a life-threatening complication of diabetes
mellitus characterized by severe hyperglycemia, hyperosmolarity, and dehydration without
significant ketoacidosis.
What is the primary treatment for hypoglycemia in conscious patients?
a) Glucagon injection
b) Intravenous dextrose
c) Oral glucose
d) Insulin infusion
Answer: c) Oral glucose
Rationale: The primary treatment for hypoglycemia in conscious patients is the administration of
oral glucose, such as glucose tablets or juice.
Which of the following hormones is responsible for regulating water balance in the body?
a) Insulin
b) Antidiuretic hormone (ADH)
c) Glucagon
d) Growth hormone
Answer: b) Antidiuretic hormone (ADH)
Rationale: Antidiuretic hormone (ADH), also known as vasopressin, regulates water balance by
controlling the reabsorption of water in the kidneys.
What is the classic triad of symptoms associated with diabetes insipidus?
a) Polyuria, polydipsia, and dehydration
b) Hyperglycemia, ketosis, and acidosis
c) Hypotension, tachycardia, and diaphoresis
d) Bradycardia, hypothermia, and constipation
Answer: a) Polyuria, polydipsia, and dehydration
Rationale: Diabetes insipidus is characterized by excessive urination (polyuria), excessive thirst
(polydipsia), and dehydration due to the inability to concentrate urine.
Which of the following laboratory findings is consistent with syndrome of inappropriate
antidiuretic hormone (SIADH)?
