A new, non-invasive scan successfully identifies adrenal adenomas – small benign tumors that overproduce aldosterone, thus causing primary aldosteronism, one of the leading causes of hypertension. The scan also predicted whether patients could expect a resolution of their hypertension symptoms with surgical removal of the adenomas.
The two-stage study involved 128 patients who had an adrenal adenoma. In the first stage, researchers administered the patients a short-acting dose of metomidate, a radioactive dye that preferentially targets adrenal adenomas. Then they performed MRIs on the patients to determine if the dye facilitated the tumors' identification – a means to predict whether surgical removal of the tumor(s) would resolve the participant’s hypertension.
In the second stage, they performed adrenal vein sampling on the patients, the traditional means of diagnosing primary aldosteronism. Adrenal vein sampling is an invasive procedure that involves the collection of blood from both adrenal glands via a catheter inserted in the groin.
They found that both procedures successfully predicted whether a surgical intervention could resolve the patients' hypertension, but the non-invasive procedure involving metomidate was slightly more successful, correctly identifying approximately 73 percent of the patients versus 64 percent with the adrenal vein sampling.
Primary aldosteronism is a disorder in which the body’s adrenal glands produce too much aldosterone, a hormone that regulates blood pressure by balancing sodium and potassium levels in the body. The condition accounts for 5 to 14 percent of all hypertension cases and 20 to 25 of treatment-resistant hypertension cases; however, many people with primary aldosteronism go undiagnosed.
This study demonstrates that a non-invasive technique accurately diagnoses adrenal adenomas and identifies potential surgical candidates for adrenal adenoma removal.