Retrospective Cushing’s Diagnosis Done via Hair Test, Case Report Shows

A woman with undiagnosed Cushing’s disease experienced a resolution of her hypercortisolism symptoms after a spontaneous pituitary apoplexy, and was retrospectively diagnosed via hair cortisol analysis, according to a recent case report.

This study highlights the utility of testing cortisol levels in hair as a means of identifying Cushing’s disease in cases that might otherwise be difficult to definitively diagnose.

The case was described in The Netherlands Journal of Medicine, in a report titled “Spontaneous remission of unidentified Cushing’s disease revealed by hair cortisol analysis.”

Cushing’s disease is caused by a tumor in the pituitary gland, which leads to abnormally high levels of the hormone cortisol in the body. High cortisol levels of any cause constitute Cushing’s syndrome, of which Cushing’s disease is one form; it comprises about 70% of all cases.

Pituitary apoplexy occurs when the blood supply to the pituitary gland is blocked, for example, as the result of a hemorrhage.

Though very rare, there have been some previous reports of people with Cushing’s-like symptoms, who experienced a resolution of these manifestations after a pituitary apoplexy. Conceptually, because the apoplexy causes damage to the pituitary gland (and any tumor therein), it can ultimately lead to the reduced secretion of pituitary hormones like cortisol.

However, this poses a diagnostic challenge because it is generally necessary to measure high cortisol levels in the body in order to definitively diagnose Cushing’s syndrome. As such, if a patient with undiagnosed Cushing’s goes to the hospital after a pituitary apoplexy, it can be difficult to diagnose that individual with the underlying Cushing’s unless the syndrome relapses.

The new report describes a 31-year-old woman who went to the hospital after experiencing a thunderclap headache — an intense and very painful headache that occurs very suddenly. Her other reported symptoms included light-headedness, loss of appetite, nausea, and vomiting. The patient’s medical history included hypertension (high blood pressure), type 2 diabetes mellitus, polycystic ovary syndrome, and hypothyroidism, or an underactive thyroid.

According to the case report’s authors, a physical examination of the patient at the hospital “was suggestive for Cushing’s syndrome,” as evidenced by features like moon face, central obesity, and acne.

A magnetic resonance imaging (MRI) scan revealed a pituitary apoplexy in a previously undiagnosed pituitary macroadenoma, which is a type of pituitary gland cancer.

Laboratory assessments were consistent with complete anterior hypopituitarism, meaning that there were very low levels of cortisol and other pituitary-associated hormones in the patient’s blood.

The woman underwent treatment, that included hydrocortisone, which is essentially replacement cortisol. Such treatment eventually controlled all of her symptoms.

“Due to the presence of complete anterior hypopituitarism at presentation, the clinical suspicion of pre-existing Cushing’s disease could not [be] biochemically confirmed,” the researchers wrote.

However, they were ultimately able to diagnose the patient’s Cushing’s disease by analyzing cortisol levels in her hair, which was 22 centimeters long (about 8.7 inches).

Hair cortisol analysis is a fairly new technology. The general idea is that measuring cortisol in older hair — specifically the hair furthest from the scalp — can reflect cortisol levels over time. Each centimeter of hair corresponds to roughly one month.

This hair analysis revealed that, over the preceding 22 months, the patient’s cortisol levels had fluctuated, but were consistently elevated. The average hair cortisol level was 25 picograms/ml, which is nearly 10 times higher than the normal reference value of 2.7 pg/mg in hair.

“We therefore confirmed the diagnosis of Cushing’s disease in our patient cured by pituitary apoplexy,” the researchers wrote.

“This is the first case in which the diagnosis was proven in retrospect by hair cortisol analysis,” they added.

This diagnosis was important, as it allowed the patient’s healthcare team to tailor her treatment more effectively. For instance, “after establishing the diagnosis, we were able to taper corticosteroid therapy at a rate that is indicated for Cushing’s disease in remission to prevent steroid withdrawal symptoms,” the investigators wrote.

Overall, this case highlights the utility of hair cortisol tests for diagnosing Cushing’s disease, especially in complicated cases.

“Hair cortisol analysis provides a useful tool for the clinician to provide proper care,” the researchers concluded.

“In our opinion, hair cortisol analysis should be considered in patients presenting with pituitary apoplexy and signs or symptoms of Cushing’s disease,” they wrote.