ENDOCRINE- PRACTICE QUESTIONS Flashcards
What is the primary difference between Cushing Disease and Cushing Syndrome?
A) Cushing Disease involves plasma level changes, while Cushing Syndrome involves changes in bone density.
B) Cushing Disease is caused by excessive cortisol production due to ACTH-secreting pituitary tumors, while Cushing Syndrome is due to any cause of elevated cortisol levels.
C) Cushing Disease is only diagnosed in children, whereas Cushing Syndrome is exclusively an adult condition.
D) Cushing Disease is less severe than Cushing Syndrome.
Answer:** B) Cushing Disease is caused by excessive cortisol production due to ACTH-secreting pituitary tumors, while Cushing Syndrome is due to any cause of elevated cortisol levels.
Rationale: Cushing Disease specifically refers to excess cortisol resulting from excessive secretion of ACTH from a pituitary tumor. Cushing Syndrome, on the other hand, encompasses all conditions leading to excess cortisol, whether from endogenous production or exogenous sources.
Which of the following is the most common clinical feature shared by patients with Cushing Syndrome?
A) Persistent fever
B) Unexplained weight loss
C) Weight gain
D) Persistent headaches
Answer:** C) Weight gain
Rationale: Weight gain is a common and prominent feature in patients with Cushing Syndrome due to cortisol’s effects on metabolism, typically resulting in central obesity.
Which of the following is the most common exogenous cause of Cushing Syndrome?
A) Long-term use of corticosteroid medications
B) Pituitary adenomas
C) Adrenal hyperplasia
D) Ectopic ACTH secretion
Answer:** A) Long-term use of corticosteroid medications
Rationale: Prolonged use of exogenous glucocorticoids, such as those used to treat inflammatory conditions, is the most common cause of Cushing Syndrome due to excess glucocorticoid exposure
The initial screening tests for diagnosing Cushing Syndrome include all of the following EXCEPT:
A) Midnight salivary cortisol
B) 1 mg overnight dexamethasone suppression test
C) Serum insulin level
D) 24-hour urinary free cortisol test
Answer:** C) Serum insulin level
Rationale: Screening for Cushing Syndrome typically involves tests to assess cortisol levels, such as midnight salivary cortisol, the dexamethasone suppression test, and 24-hour urinary free cortisol tests. Serum insulin is not used for diagnosing Cushing Syndrome.
Which of the following tests can help differentiate whether cortisol excess is due to Cushing Syndrome or pseudo-Cushing states such as severe obesity or depression?
A) Serum ACTH level
B) Low-dose dexamethasone suppression test
C) CT scan of the abdomen
D) Testing for ketone bodies in urine
Answer:** B) Low-dose dexamethasone suppression test
Rationale: The low-dose dexamethasone suppression test is specifically used to differentiate Cushing’s symptoms from pseudo-Cushing states by assessing feedback inhibition on the hypothalamic-pituitary-adrenal (HPA) axis.
When would an MRI of the pituitary gland typically be indicated for a patient suspected of having Cushing Disease?
A) After confirmation of an adrenal tumor
B) Before any hormonal assessment
C) To identify microadenomas of the pituitary gland after hormonal studies suggest a pituitary origin of hypercortisolemia
D) Only if symptoms persist after initial surgical treatment
Answer:** C) To identify microadenomas of the pituitary gland after hormonal studies suggest a pituitary origin of hypercortisolemia
Rationale: An MRI of the pituitary is indicated to detect microadenomas when hormonal studies confirm the pituitary as the source of ACTH overproduction.
What is the primary surgical treatment option for primary hypersecretion of ACTH by the pituitary gland in Cushing Disease?
A) Bilateral adrenalectomy
B) Laparoscopic adrenalectomy
C) Transsphenoidal microsurgery
D) Open thoracotomy
*Answer:** C) Transsphenoidal microsurgery
Rationale: Transsphenoidal microsurgery is the primary surgical method to remove ACTH-secreting pituitary tumors, which is pivotal in treating Cushing Disease.
Which of the following imaging studies is beneficial for detecting ectopic ACTH secretion?
A) Echocardiogram
B) Chest X-ray
C) CT scan of the chest and abdomen
D) Thyroid ultrasound
Answer:** C) CT scan of the chest and abdomen
Rationale: A CT scan of the chest and abdomen is crucial in identifying ectopic ACTH secretion, as the lungs are a common source of such secretion.
Which of the following drugs is commonly used for adrenal replacement therapy in patients requiring hormone supplementation after treatment for Cushing Disease or Syndrome?
A) Metformin (Glucophage)
B) Lisinopril (Zestril)
C) Hydrocortisone (Cortef)
D) Omeprazole (Prilosec)
Answer:** C) Hydrocortisone (Cortef)
Rationale: Hydrocortisone is a corticosteroid often used for adrenal replacement therapy to maintain appropriate hormone levels after treatment for Cushing Disease or Syndrome.
What is a potential complication of untreated or inadequately treated Cushing Disease?
A) Hypoglycemia
B) Increased susceptibility to infections
C) Decreased blood pressure
D) Fungal skin infections
*Answer:** B) Increased susceptibility to infections
Rationale: Untreated or inadequately treated Cushing Disease can lead to an increased susceptibility to infections due to altered immune responses and high cortisol levels.
Which intervention is NOT typically recommended to treat secondary complications of Cushing Disease/Syndrome even after successful treatment?
A) Osteoporosis management
B) Blood pressure control
C) Immunosuppressive therapy
D) Blood glucose monitoring
*Answer:** C) Immunosuppressive therapy
Rationale: Immunosuppressive therapy is inappropriate for treating secondary complications like obesity, hypertension, glucose intolerance, and osteoporosis post-treatment of Cushing’s. Management focuses on stabilization and monitoring of these specific areas rather than suppressing the immune system.
What primarily causes Type 1 Diabetes Mellitus?
A) Insulin resistance due to obesity
B) Pancreatic β-cell destruction resulting in insulin deficiency
C) Excess production of glucagon
D) Viral infection directly causing hyperglycemia
Answer:** B) Pancreatic β-cell destruction resulting in insulin deficiency
Rationale: Type 1 Diabetes Mellitus is primarily caused by the destruction of pancreatic β-cells, leading to an insulin deficiency that results in hyperglycemia.
Which of the following autoantibodies is commonly tested to diagnose immune-mediated Type 1 Diabetes?
A) Anti-nuclear antibodies (ANA)
B) Anti-thyroid peroxidase antibodies (TPO)
C) Glutamic acid decarboxylase 65 antibody (GAD65)
D) Anti-mitochondrial antibodies
Answer:** C) Glutamic acid decarboxylase 65 antibody (GAD65)
Rationale: GAD65 is one of the autoantibodies commonly present in immune-mediated T1DM, and its presence helps confirm the autoimmune nature of the disease.
Which of the following is NOT considered a classic symptom of Type 1 Diabetes Mellitus?
A) Polyphagia
B) Polyuria
C) Polydipsia
D) Persistent cough
*Answer:** D) Persistent cough
Rationale: Persistent cough is not a classic symptom of Type 1 Diabetes Mellitus. The typical symptoms include polyuria, polydipsia, and polyphagia.
A patient presents with signs of dehydration, polyuria, polydipsia, and has lost weight despite increased appetite. Laboratory tests reveal a blood glucose level of 300 mg/dL. What is the most likely diagnosis?
A) Type 1 Diabetes Mellitus
B) Type 2 Diabetes Mellitus
C) Diabetes Insipidus
D) Hypoglycemia
Answer:** A) Type 1 Diabetes Mellitus
Rationale: The combination of symptoms (dehydration, polyuria, polydipsia, polyphagia with weight loss) and hyperglycemia strongly suggests Type 1 Diabetes Mellitus, especially in the context of insulin deficiency.
What is a significant risk factor for the development of Type 1 Diabetes Mellitus?
A) High BMI and sedentary lifestyle
B) Autoimmune conditions and family history
C) Long-term use of corticosteroids
D) High-carbohydrate diet
*Answer:** B) Autoimmune conditions and family history
Rationale: Autoimmune mechanisms and genetic predisposition (family history) are significant risk factors for developing T1DM. It is often linked with other autoimmune diseases and can run in families.
Which physical examination finding is indicative of possible diabetic ketoacidosis (DKA) in a patient with Type 1 Diabetes?
A) Bradycardia
B) Edema
C) Altered breathing pattern
D) Jaundice
*Answer:** C) Altered breathing pattern
Rationale: An altered breathing pattern, specifically Kussmaul respiration (deep and labored breathing), is a classic sign of metabolic acidosis, which occurs in diabetic ketoacidosis.
Which of the following lab results definitively confirms a diagnosis of diabetes mellitus?
A) Fasting plasma glucose of 115 mg/dL
B) Glycosylated hemoglobin (A1c) of 6.5%
C) Two-hour plasma glucose of 180 mg/dL during an oral glucose tolerance test (OGTT)
D) Random plasma glucose of 180 mg/dL in a patient with no symptoms
Answer:** B) Glycosylated hemoglobin (A1c) of 6.5%
Rationale: An A1c level of 6.5% or higher is one of the criteria used to diagnose diabetes mellitus. It provides a measure of the average blood glucose level over the past 2 to 3 months.
Which laboratory test is used to assess residual beta cell function and endogenous insulin production in a patient with T1DM?
A) Hemoglobin A1c
B) C-peptide level
C) Random plasma glucose
D) Free fatty acid level
Answer:** B) C-peptide level
Rationale: C-peptide levels reflect endogenous insulin production because C-peptide is released in equal amounts with insulin. This test helps evaluate beta cell function in the pancreas.
What is the recommended adult target for HbA1c levels in most patients with Type 1 Diabetes?
A) Less than 5%
B) Less than 6.5%
C) Less than 6%
D) Less than 7%
*Answer:** D) Less than 7%
Rationale: The general target for HbA1c in adults with diabetes is less than 7% to reduce the risk of complications while balancing the potential for hypoglycemia.
Which statement is true regarding the management of hypoglycemia in patients with Type 1 Diabetes?
A) Hypoglycemia is only a concern with Type 2 Diabetes.
B) A plasma glucose level of less than 70 mg/dL is the threshold for hypoglycemia intervention.
C) Severe hypoglycemia is classified as a blood glucose level of 90 mg/dL.
D) High-protein food is the preferred treatment for hypoglycemia.
*Answer:** B) A plasma glucose level of less than 70 mg/dL is the threshold for hypoglycemia intervention.
Rationale: Hypoglycemia intervention is recommended when glucose levels drop below 70 mg/dL. Rapid ingestion of carbohydrates is recommended, and severe hypoglycemia is further defined as less than 54 mg/dL.
A patient with Type 1 Diabetes experiences severe hypoglycemia and is unconscious. What is the most appropriate immediate treatment?
A) Provide an oral glucose gel
B) Administer an intravenous glucose solution
C) Give 1 mg of glucagon subcutaneously
D) Make the patient drink a sugary beverage
Answer:** C) Give 1 mg of glucagon subcutaneously
Rationale: For severe hypoglycemia that results in unconsciousness, glucagon should be administered to mobilize hepatic glucose stores since oral administration is not possible.
In insulin therapy for Type 1 Diabetes, what is a typical starting total daily dose of insulin for insulin-naive patients?
A) 0.1–0.2 units/kg/day
B) 0.2–0.4 units/kg/day
C) 0.5–0.7 units/kg/day
D) 1.0 unit/kg/day
Answer:** B) 0.2–0.4 units/kg/day
Rationale: The recommended total initial dose for insulin-naive patients starting insulin therapy is 0.2–0.4 units/kg/day, with adjustments made based on blood glucose monitoring.
What is the recommended dietary approach for patients with Type 1 Diabetes to allow flexibility in eating habits?
A) Ketogenic diet
B) Glycemic index monitoring
C) Carbohydrate counting using insulin-to-carbohydrate ratios
D) Low-fat diet only
Answer:** C) Carbohydrate counting using insulin-to-carbohydrate ratios
Rationale: Carbohydrate counting with insulin-to-carbohydrate ratios is recommended as it allows individuals with Type 1 Diabetes flexibility in managing their diet with varying carbohydrate intake at meals and snacks.