Primary Care Physicians Need to be More Aware of Cushing’s Disease Signs, Researchers Advise

Primary care physicians need to be aware of the typical signs of Cushing’s disease so they can initiate early screening, advocates a group of researchers from the University of Ghana.

Their article, “Screening for Cushing Syndrome at the Primary Care Level: What Every General Practitioner Must Know,” was an attempt to increase awareness of the condition among doctors. Their work was published in the International Journal of Endocrinology.

Although Cushing’s syndrome is a relatively common result of prolonged exposure to glucocorticoid drugs, Cushing’s disease — when it occurs as a result of a cortisol-producing tumor — is a rare condition.

Consequently, doctors in primary care might not relate the signs of the disease to the condition. Using  Endocrine Society Guidelines, the researchers underscored five features that indicate a patient might have Cushing’s disease.

Weight gain, with fat mainly in the abdomen and face while legs and arms are lean, are typical signs of the disease. But doctors also need to be on the lookout for when these signs, which also appear as reddish stretch marks, weak muscles and brittle bones, appear to be progressing.

In some cases, the signs can be easier to interpret, such as when muscle weakness and osteoporosis appears in a young patient. It also is crucial to react to retarded growth in children, particularly if height is low in combination with weight gain.

Finally, accidentally identified tumors in the adrenal glands should always prompt an investigation, researchers said.

The team also underscored that it is crucial for primary care physicians not to rely on random cortisol measurements, as these are known to be highly variable, making them unreliable markers of disease. Nevertheless, there is no single ideal screening test, they maintained.

Such tests need to exclude so-called pseudo-Cushing’s syndrome, in which high cortisol levels are caused by another medical issue.

The guidelines recommended a set of tests and the order in which they should be used.

First, doctors should test the 24-hour urinary free cortisol, as increased cortisol accumulates in urine. Next, they should consider late-night salivary cortisol. In healthy people, cortisol levels vary in a diurnal rhythm and reach its lowest point late at night. People with Cushing’s disease lose this variability and have high levels also late at night.

Finally, a dexamethasone suppression test can be used. This test indicates there is a loss of feedback inhibition of the hormonal system producing cortisol. This is typically seen when a person has been exposed to high cortisol levels for a long time.

For more certainty, more than one test can be performed, they said.

If any of these tests come back positive, the physician should refer the patient to an endocrinologist, the researchers recommended.