ITE Endocrinology 5 — Questions and Answers
Question 1: A 55-year-old postmenopausal woman is found to have a T-score of -2.8 at the lumbar spine. She has no prior fractures. FRAX 10-year hip fracture probability is 4%. What is the most appropriate next step?
- Initiate bisphosphonate therapy immediately
- Reassess with FRAX including bone mineral density and treat if major osteoporotic fracture risk ≥20% or hip ≥3% (Correct answer)
- Start teriparatide given T-score below -2.5
- Repeat DEXA scan in 1 year
Correct answer: Reassess with FRAX including bone mineral density and treat if major osteoporotic fracture risk ≥20% or hip ≥3%
NOF/AACE guidelines recommend pharmacotherapy when 10-year major osteoporotic fracture risk ≥20% or hip fracture risk ≥3%, using FRAX with BMD integrated into the decision.
Question 2: A patient presents with hypercalcemia, low PTH, elevated PTHrP, and a lung mass. What is the mechanism of hypercalcemia?
- Ectopic PTH secretion by the tumor
- Humoral hypercalcemia of malignancy via PTHrP (Correct answer)
- Excessive calcitriol production by granulomas
- Osteolytic metastases releasing calcium
Correct answer: Humoral hypercalcemia of malignancy via PTHrP
PTHrP (PTH-related peptide) secreted by squamous cell carcinomas mimics PTH action, causing humoral hypercalcemia of malignancy with suppressed native PTH.
Question 3: A patient with hyperthyroidism presents to the ED with fever of 104°F, tachycardia of 148 bpm, altered mental status, and vomiting. What is the immediate treatment priority?
- Radioactive iodine ablation
- High-dose PTU, beta-blocker, iodine solution (given after PTU), and glucocorticoids (Correct answer)
- Emergent thyroidectomy
- IV methimazole alone
Correct answer: High-dose PTU, beta-blocker, iodine solution (given after PTU), and glucocorticoids
Thyroid storm requires PTU to block synthesis and conversion, beta-blockers for rate control, iodine (given 1 hour after PTU) to block release, and corticosteroids to prevent adrenal crisis.
Question 4: Which of the following is the mechanism of action of empagliflozin in reducing cardiovascular mortality in type 2 diabetes?
- Increases insulin secretion from beta cells
- Inhibits SGLT-2 in the proximal tubule causing glucosuria, natriuresis, and volume reduction (Correct answer)
- Activates GLP-1 receptors in the heart
- Reduces hepatic glucose output via AMPK activation
Correct answer: Inhibits SGLT-2 in the proximal tubule causing glucosuria, natriuresis, and volume reduction
SGLT-2 inhibitors reduce glucosuria, promote natriuresis and osmotic diuresis, lowering preload and afterload, which underlies their heart failure and CV mortality benefits.
Question 5: A 45-year-old woman with no prior thyroid disease is found to have TSH of 6.8 mIU/L and normal free T4 on two separate measurements. She is asymptomatic and not pregnant. What is the most appropriate management?
- Start levothyroxine immediately
- Obtain thyroid antibodies; treat if positive or TSH >10 (Correct answer)
- Refer for radioactive iodine uptake scan
- Order thyroid ultrasound-guided biopsy
Correct answer: Obtain thyroid antibodies; treat if positive or TSH >10
Subclinical hypothyroidism with TSH <10 in an asymptomatic, non-pregnant patient warrants observation; treatment is considered if TPO antibodies are positive or TSH exceeds 10 mIU/L.
Question 6: A patient with acromegaly has persistent elevated IGF-1 after transsphenoidal surgery. Which medical therapy directly targets somatostatin receptors to suppress GH?
- Cabergoline
- Pegvisomant
- Octreotide LAR (Correct answer)
- Bromocriptine
Correct answer: Octreotide LAR
Somatostatin analogs (octreotide, lanreotide) bind somatostatin receptors to suppress GH secretion and reduce IGF-1 levels in persistent acromegaly.
Question 7: A 30-year-old woman presents with episodic headaches, palpitations, and diaphoresis. Blood pressure during an episode is 210/120 mmHg. 24-hour urine metanephrines are 3× the upper limit of normal. CT abdomen shows a 3 cm right adrenal mass. What is the correct sequence of management?
- Proceed directly to surgical resection
- Start alpha-blockade first, add beta-blocker after adequate alpha-blockade, then surgery (Correct answer)
- Begin beta-blocker immediately to control tachycardia
- Start both alpha and beta blockers simultaneously before surgery
Correct answer: Start alpha-blockade first, add beta-blocker after adequate alpha-blockade, then surgery
Alpha-blockade must precede beta-blockade to prevent unopposed vasoconstriction; beta-blockers alone can precipitate hypertensive crisis in pheochromocytoma.
ITE Endocrinology 5
A 55-year-old postmenopausal woman is found to have a T-score of -2.8 at the lumbar spine.
She has no prior fractures.
FRAX 10-year hip fracture probability is 4%.
What is the most appropriate next step?