A 37-Year-Old Woman Is Evaluated for Generalized Weakness

A 37-year-old woman is evaluated for generalized weakness.  She has been hospitalized twice over the last year with similar complaints and her serum potassium concentration was found to be < 3.0 mEq/L.  Her potassium concentration returned to normal with aggressive potassium replacement.  She eats a normal diet and denies vomiting, purging, and cathartic or diuretic use.  Her blood pressure is within normal limits.  Her only medication is an oral contraceptive.  Her review of systems is otherwise unremarkable.  Her sister suffers from Crohn's disease and her mother has congestive heart failure, diabetes mellitus, and bipolar disorder.
Her blood pressure is 112/68 mm Hg and her pulse is 90/min.  Her BMI is 22 kg/m².  Physical examination is normal.
Laboratory studies are shown below:

Spot urinary chloride concentrations on two separate occasions were 15 and 65 mEq/L.
Which of the following is most likely to establish diagnosis in this patient?

A) CT angiography of renal arteries
B) Colonoscopy
C) Plasma aldosterone and renin levels
D) Serum insulin and C-peptide levels
E) Urine screen for diuretics

Correct Answer:

Verified

Unlock this answer now
Get Access to more Verified Answers free of charge

Access For Free