Conn's syndrome

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What is a Conn’s syndrome?

Conn’s syndrome is a condition associated with the development of high blood pressure and low potassium levels in the blood. In patient with a recent diagnosis of hypertension ( high blood pressure), the findings of a low potassium level should lead to a search for this disease since it is a curable cause for high blood pressure.

Patients with Conn’s syndrome have a tumor in their adrenal cortex (the outer part of the adrenal gland) that produces an excessive amount of a hormone aldosterone. Aldosterone is a hormone that is normally involved in regulating the amount of salt in the body. In patients who have overproduction of this hormone, excessive amount of salt is retained in their body and potassium is lost, leading to high blood pressure and low potassium levels.

What is the cause for Conn’s syndrome?

In the majority of patients a small tumor is found in the adrenal cortex (the outer part of the adrenal gland). Excess production of aldosterone by the tumor leads to the development of Conn’s syndrome with high blood pressure and low potassium levels. Not all patients with a Conn’s syndrome will have a tumor. In a small group of patients abnormal function of the adrenal cortex from a condition called adrenal hyperplasia may give rise to the Conn’s syndrome.

Surgical removal of the tumor can lead to cure of the high blood pressure and low potassium levels in patients with Conn’s syndrome. In patients who have abnormal function of the adrenal gland due to adrenal hyperplasia, surgery is usually not recommended.

How are adrenal tumors diagnosed?

A thin section CT scan of the adrenal glands can diagnose between 75% and 95% of the adrenal tumors that causes a Conn’s syndrome. Very small tumors less than 7 mm may be missed on CT scanning.

Where this diagnosis is suspected and a tumor is not seen on CT scan, a specialized test available at USC called differential venous sampling for aldosterone may provide the diagnosis for this disorder. In this test a radiologist inserts a small catheter into the adrenal vein (the blood vessel that transports blood away from the adrenal glands) to measure for the amount of the hormone aldosterone in the blood on the two sides of the body. In patients who have a tumor, the side where the tumor is located will show excessive amounts of aldosterone on the tested blood.

How is Conn’s syndrome treated?

Surgical removal of the adrenal gland where the tumor is located is the treatment of choice. This operation called an adrenalectomy will lead to cure of the blood pressure and the low potassium problems in patients with Conn’s syndrome. After removal of the tumor blood pressure levels usually return to normal in most patients. Occasionally in some patients that have had a tumor for long time, persistent elevation in their blood pressure may continue after the surgery due to preexisting damage to their blood vessels.

Laparoscopic adrenalectomy is a treatment of choice for removing the adrenal gland in patients with a Conn’s syndrome. Since these are benign small tumors an open surgical operation is not indicated due to the excessive amount of pain, discomfort and the prolonged healing periods required for the open operation compared to the laparoscopic operation. Please click on this link for a detailed description of laparoscopic adrenalectomy.

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Programs: pancreatic cancer, pancreatitis, laparoscopic surgery, endocrine surgery,
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