MD Endocrine and Metabolic Disorders 5 — Questions and Answers
Question 1: A 32-year-old woman with type 1 diabetes presents with recurrent hypoglycemia unawareness. Which physiologic response is impaired?
- Increased glucagon secretion from alpha cells (Correct answer)
- Increased insulin secretion to compensate
- Decreased cortisol release
- Increased renal glucose reabsorption
Correct answer: Increased glucagon secretion from alpha cells
Longstanding type 1 diabetes impairs glucagon counterregulatory response to hypoglycemia, removing a critical defense mechanism against low blood sugar.
Question 2: A patient's labs show: glucose 90 mg/dL, sodium 130 mEq/L, potassium 5.8 mEq/L, bicarbonate 14 mEq/L, and a morning cortisol of 2 mcg/dL. ACTH stimulation test shows a blunted response. Which diagnosis fits?
- Secondary adrenal insufficiency
- Primary adrenal insufficiency (Addison's disease) (Correct answer)
- Conn's syndrome
- Cushing's disease
Correct answer: Primary adrenal insufficiency (Addison's disease)
Primary adrenal insufficiency features hyperkalemia (from mineralocorticoid deficiency), hyponatremia, and a blunted cortisol response to ACTH stimulation.
Question 3: A 55-year-old woman is found to have a thyroid nodule. Fine-needle aspiration cytology shows 'follicular neoplasm' (Bethesda IV). What is the recommended next step?
- Repeat FNA in 6 months
- Radioactive iodine ablation
- Diagnostic hemithyroidectomy (lobectomy) (Correct answer)
- Observation with annual ultrasound
Correct answer: Diagnostic hemithyroidectomy (lobectomy)
Bethesda IV cytology cannot distinguish follicular adenoma from carcinoma on FNA; surgical lobectomy is required for definitive histologic diagnosis.
Question 4: A 19-year-old woman with a BMI of 17 has oligomenorrhea and labs showing low FSH, LH, and estradiol with normal TSH and prolactin. What is the most likely cause of her hypogonadism?
- Premature ovarian insufficiency
- Hypothalamic amenorrhea (functional) (Correct answer)
- Polycystic ovary syndrome
- Hyperprolactinemia
Correct answer: Hypothalamic amenorrhea (functional)
Low body weight and energy deficit suppress GnRH pulse frequency, causing hypothalamic amenorrhea with low FSH, LH, and estradiol.
Question 5: A diabetic patient develops painful peripheral neuropathy. Tight glycemic control is initiated. Which additional medication has the best evidence for symptomatic relief of diabetic peripheral neuropathy?
- Gabapentin or pregabalin (Correct answer)
- NSAIDs
- Methotrexate
- Hydrocodone alone
Correct answer: Gabapentin or pregabalin
Gabapentin and pregabalin are FDA-approved and first-line agents for painful diabetic peripheral neuropathy, modulating calcium channel activity in sensory neurons.
Question 6: A 70-year-old man with diabetes and CKD stage 3 has an HbA1c of 9.2%. His provider avoids aggressive glycemic targets. What is the primary reason for setting a less stringent HbA1c goal (e.g., <8%)?
- Reduced cardiovascular benefit in elderly
- Increased risk of hypoglycemia with limited ability to recognize or recover (Correct answer)
- Lower cost of medications
- Reduced need for monitoring in CKD
Correct answer: Increased risk of hypoglycemia with limited ability to recognize or recover
Elderly patients with CKD have blunted hypoglycemia counterregulation and impaired drug clearance, making tight control dangerous with high hypoglycemia risk.
Question 7: A 38-year-old man has central obesity, hypertension, and a fasting glucose of 118 mg/dL. His triglycerides are 220 mg/dL and HDL is 32 mg/dL. How many criteria for metabolic syndrome does he meet?
- 2
- 3
- 4 (Correct answer)
- 5
Correct answer: 4
He meets 4 criteria: central obesity, hypertension, impaired fasting glucose (≥100), elevated triglycerides (≥150), and low HDL — metabolic syndrome requires ≥3.
MD Endocrine and Metabolic Disorders 5
A 32-year-old woman with type 1 diabetes presents with recurrent hypoglycemia unawareness.
Which physiologic response is impaired?