Conn's Syndrome

Most often, patients have higher than normal blood pressure. Blood tests help to tell if high blood pressure is from Conn’s Syndrome or something else. Medications for high blood pressure often don’t help treat hyperaldosteronism.

The abnormal electrolyte levels often seen with too much aldosterone lead to signs such as:

• Muscle twitching and cramps
• Constipation

Some other, although very rare, symptoms may include:

• Lack of muscle strength
• Frequent voiding
• Nighttime voiding
• Headache
• Increased thirst
• Pins and needles feeling
• Eyesight problems
• Paralysis that comes and goes

The severity may depend on the degree of the electrolyte abnormality.

Primary hyperaldosteronism

Most cases are not inherited, but some are passed down from a parent. Conn’s Syndrome is due to a tumor on the adrenal gland (a benign cortical adenoma), causing too much aldosterone to be released.

Secondary hyperaldosteronism

Sometimes too much aldosterone is caused by some other health issue that lowers blood flow to the kidney. This is not Conn’s Syndrome. These cases are called "secondary hyperaldosteronism" and this term is used because the excess hormone is not from a problem with the adrenal gland. Examples are:

• Fluid loss
• Kidney artery narrowing
• Heart failure
• Shock
• Liver disease
• Pregnancy
• Some kidney tumors

Blood tests can check for high aldosterone. Your health care team may order a CT scan or MRI to find the side (right or left) of an adenoma or hyperplasia. Patients who have adrenal masses only need to be screened for Conn’s syndrome if they are known to have blood pressure issues. If patients with an adrenal mass are found to have a high aldosterone level on a blood test, a special test known as adrenal vein sampling must be done before the adrenal gland with the mass is surgically removed, since in up to one third of patients the problem can stem from both adrenal glands or just the opposite adrenal gland.

Primary hyperaldosteronism, caused by a tumor, is most often treated by removing the adrenal gland with the tumor. This is called unilateral adrenalectomy and is when a surgeon takes out one of the adrenal glands.  This surgery is almost always done laparoscopically. This is when a few small cuts provide access for surgical tools and a camera to be placed inside the body through these openings. A video screen is then linked to the camera. Using the video screen as a guide, the surgeon will hold the tools to complete the surgery. This may be done with or without the assistance of a robot.

It's of great value to know adrenal surgery may be complex. It helps to choose a surgeon who has significant experience with surgery in the area around the kidneys and adrenal glands. Strive to talk with a few surgeons before you choose one to work with.

Most patients have a rapid and uneventful recovery from surgery. High blood pressure is greatly improved in 80 to 90 out of 100 of cases. But even after surgery, you may still have high blood pressure. You may need drugs after surgery for hours or weeks until your blood pressure returns to normal. The reason for this is not fully understood.

You should still see your health care team after treatment so they can confirm normalization of aldosterone levels in the blood and also monitor your blood pressure and electrolytes levels.

Updated August 2024.