Incidental adrenal mass leads to man’s Cushing’s diagnosis: Report
Complex case highlights need for careful testing to find true cause of hormone disorder
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After an unrelated medical exam revealed a mass on a man’s right adrenal gland, further testing showed his symptoms were actually caused by Cushing’s disease, rooted in a small pituitary tumor in the brain, according to a case report.
The case highlights the need for careful testing to find the true cause of a hormone disorder before surgery, researchers wrote.
Researchers at Northwestern University Feinberg School of Medicine in Chicago also found that the patient’s excess aldosterone, a steroid hormone, was coming from his left adrenal gland. The mass on his right adrenal gland, which had initially raised concern, was not producing hormones and was not the cause of the problem.
“Our case report highlights the importance of localizing the functioning lesion in the context of an adrenal incidentaloma [an adrenal mass found by chance],” researchers wrote in “Cushing disease and unilateral primary aldosteronism confounded by a nonfunctioning contralateral adrenal incidentaloma,” which was published in JCEM Case Reports.
Scan for pancratitis reveals mass on right adrenal gland
Cushing’s disease occurs when a tumor in the brain’s pituitary gland produces and releases an excess of adrenocorticotropic hormone (ACTH), which signals the production of cortisol by the adrenal glands. An excess of cortisol can lead to a range of symptoms, including high blood pressure, weight gain, and a buildup of fat around the abdomen, face, and neck.
In this case, a 53-year-old man with obesity, high blood pressure, depression, and anxiety was referred to an endocrinologist (a specialist in hormone-related diseases) after a scan for pancreatitis (inflammation of the pancreas) revealed an incidentaloma on his right adrenal gland. An incidentaloma is an incidental finding during imaging performed for an unrelated reason.
At his first visit, doctors noticed several physical signs of Cushing’s syndrome, a group of diseases caused by an excess of cortisol, which includes Cushing’s disease. The man had fat around the abdomen and upper back, thinning of the arms and legs, thin skin, easy bruising, and facial redness.
A detailed CT scan suggested the adrenal mass was likely a noncancerous tumor. Blood tests showed his cortisol did not decrease normally after taking dexamethasone, a steroid used to test how well the body regulates cortisol levels. These results suggested that his body was producing excess cortisol on its own.
Indeed, his 24-hour urine cortisol and late-night saliva cortisol were both elevated. Normally, cortisol levels fall at night. Morning ACTH was within the normal range, and an MRI scan of the pituitary gland was first reported as normal.
Because depression and anxiety can sometimes increase cortisol, the doctors performed a desmopressin (DDAVP) stimulation test. DDAVP is an analog of a natural hormone that can stimulate the rapid release of ACTH in patients with a pituitary tumor. The man’s ACTH increased sharply after the test, supporting the diagnosis of Cushing’s disease.
Pituitary tumor found later, removed surgically
After reviewing the MRI scan again, the doctors identified a very small pituitary tumor called a microadenoma. To confirm this was the source of excess ACTH, they performed inferior petrosal sinus sampling to compare its levels in the blood near the pituitary gland with blood from the rest of the body. The results confirmed that the pituitary gland was producing an excess of ACTH.
The patient underwent a transsphenoidal adenomectomy, a surgical procedure in which surgeons remove the pituitary tumor through the nose. Laboratory testing of the tumor confirmed it was a corticotroph adenoma, meaning a pituitary tumor that produces ACTH. After surgery, the man’s cortisol levels decreased, indicating that the treatment worked.
Because the body temporarily stops producing enough cortisol after successful surgery, the man received hydrocortisone replacement treatment. Hydrocortisone is a medication that replaces cortisol until the body recovers. While his other Cushing’s symptoms eased, his high blood pressure did not resolve as expected. This persistent hypertension led doctors to suspect that a separate hormone imbalance was still actively driving his high blood pressure.
Comprehensive biochemical workup ultimately led to a diagnosis of [Cushing’s] disease as well as primary aldosteronism localized to the contralateral adrenal gland. The patient had a satisfactory clinical outcome after pituitary surgery and unilateral adrenalectomy.
The doctors then tested him again for primary aldosteronism, which causes excess production of aldosterone. This hormone increases blood pressure by controlling salt and water balance. When the man stopped spironolactone, a potassium-sparing diuretic used to treat high blood pressure, his blood pressure increased again, raising suspicion for primary aldosteronism.
Adrenal vein sampling, a procedure that measures hormone levels directly from each adrenal gland, confirmed primary aldosteronism. Surprisingly, the excess aldosterone came from the left adrenal gland, not from the originally identified right adrenal mass.
The patient had surgery to remove the left adrenal gland. After surgery, his blood pressure improved. Two years later, his symptoms remained stable, and his quality of life had improved significantly. Follow-up testing showed normal cortisol and no return of the pituitary tumor. The original right adrenal mass stayed stable in size for three years, and no further imaging was needed.
“Comprehensive biochemical workup ultimately led to a diagnosis of [Cushing’s] disease as well as primary aldosteronism localized to the contralateral adrenal gland. The patient had a satisfactory clinical outcome after pituitary surgery and unilateral adrenalectomy,” the researchers wrote.
