How do you approach checking an aldosterone to renin ratio in an outpatient with hypertension and hypokalemia that is difficult to correct with oral potassium replacement?  

Repleting potassium is very important for the adrenal vein testing. I'll still get an ARR in the setting of hypokalemia. The hypokalemia should not affect the renin. If renin is suppressed, then that'll prompt me to pursue 24-hour urine testing for aldosterone (as well as Na, K, Cr, and we also chec...

It is well known that hypokalemia can affect the aldosterone-renin ratio (ARR). Since hypokalemia directly inhibits aldosterone production, this can lead to false negative results when using ARR to screen for primary aldosteronism.  If it is difficult to correct hypokalemia with oral potassium...