A clinical trial showed that a new type of medical scan could identify specific adrenal nodules responsible for the excess hormone secretion associated with high blood pressure. It provides the first simple diagnostic tool for what you think is there.
High blood pressure is often caused by a variety of environmental, genetic, and lifestyle factors, but for some people it can be caused by a single hormonal problem. High blood pressure, as it is known, is caused by the adrenal glands producing too much of a hormone called aldosterone.
An estimated 5-10% of hypertension cases are caused by a malfunction of this hormone, which can be corrected with a simple surgical procedure to remove the offending adrenal nodules. However, primary aldosteronism is rarely diagnosed in patients due to the lack of simple diagnostic tests.
This newly developed test uses a molecule called metomidate that has a particular tendency to accumulate in adrenal nodules that produce excessive levels of aldosterone. Because the metomidate used in the test is tagged with a radioactive tracer, only the aldosterone-overproducing nodules will light up when the patient is imaged with computed tomography (CT).
“These aldosterone-producing nodules are so small that they are often missed on a routine CT scan,” said study co-author Morris Brown. It usually heals after that. “
In a newly published study, researchers report the results of a clinical trial testing the accuracy of this diagnostic CT scan. More than 100 patients with clinically confirmed primary aldosteronism were recruited and a simple scan could be as effective in diagnosing the condition as a more complex and rarely performed procedure known as adrenal vein sampling. have understood.
The findings indicate that this new CT scan is a new method for detecting cases of surgically curable hypertension. However, the technology faces major hurdles that must be overcome before it can be widely deployed.
The carbon-11 radiotracer used in this study is known to have a very short half-life of about 20 minutes. This means that the radioactive molecules used in CT scans must be made on site and used immediately. Most major medical facilities do not have on-site cyclotrons to synthesize radiotracers.
A new trial is currently underway to test another form of metomidate that has been modified to have a radioactive half-life of 2 hours. If this new tracer is equally effective, it will make the test much more accessible to most hospitals with PET scanning facilities.
Brown believes the new test will soon be widely available and, for the first time, will make it easier for doctors and patients to diagnose a type of hypertension that can be cured surgically.
“To date, 99% go undiagnosed because testing is difficult and unavailable,” said Brown. “Hopefully this is about to change.”
A new study was published in natural medicine.
Source: Queen Mary University of London
