A 35-year-old woman is being evaluated for uncontrolled hypertension. She was recently diagnosed with diabetes mellitus. Medical history is significant for mood swings. Temperature is 36.7 C (98 F), blood pressure is 150/100 mm Hg, pulse is 88/min, and respirations are 14/min. Lungs are clear on auscultation bilaterally, and the heart rhythm is regular. Abdominal auscultation fails to reveal any bruit. All peripheral pulsations are full. Laboratory results are as follows: Chest x-ray is suggestive of dorsal vertebral osteopenia. Which of the following is the most appropriate investigation?
A)Duplex scanning of renal vessels
B)Spiral CT of chest
C)Urinary catecholamine measurements
D)Aldosterone and renin estimation
E)Dexamethasone suppression test

Question

A 35-year-old woman is being evaluated for uncontrolled hypertension.  She was recently diagnosed with diabetes mellitus.  Medical history is significant for mood swings.  Temperature is 36.7 C (98 F), blood pressure is 150/100 mm Hg, pulse is 88/min, and respirations are 14/min.  Lungs are clear on auscultation bilaterally, and the heart rhythm is regular.  Abdominal auscultation fails to reveal any bruit.  All peripheral pulsations are full.  Laboratory results are as follows:  Chest x-ray is suggestive of dorsal vertebral osteopenia.  Which of the following is the most appropriate investigation?
A)Duplex scanning of renal vessels 
B)Spiral CT of chest 
C)Urinary catecholamine measurements 
D)Aldosterone and renin estimation 
E)Dexamethasone suppression test

Quizplus · Accepted Answer

Explanation: The patient's clinical features are highly suggestive of Cushing syndrome. This patient has hypertension, hyperglycemia, mood swings, osteopenia/osteoporosis, as well as hypokalemia and metabolic alkalosis (due to glucocorticoid stimulation of mineralocorticoid receptors). Screening for Cushing syndrome can be performed by an overnight dexamethasone suppression test or measurement of 24-hour urinary free cortisol level. In normal individuals, serum cortisol is typically suppressed below 3 mcg/dL after the administration of one mg of dexamethasone. False positive results can be obtained in patients with alcohol use disorder, significant depression, and malabsorption of dexamethasone. Many physicians prefer urinary free cortisol level measurement. (Choices A, B, C and D) The patient's clinical features are not suggestive of coarctation (eg, dimished femoral pulses), renal artery stenosis (eg, abdominal bruit), pheochromocytoma (eg, headaches, tachycardia), or primary hyperaldosteronism (which can cause hypokalemia and metabolic alkalosis but is less likely to explain osteopenia). Investigating for these disorders is not appropriate at this time. Educational objective: Young patients with diabetes, osteoporosis, hypertension, and hypokalemia should be screened for Cushing syndrome. Screening for Cushing syndrome can be performed by an overnight dexamethasone suppression test or measurement of 24-hour urinary free cortisol level.

A 35-Year-Old Woman Is Being Evaluated for Uncontrolled Hypertension