ACTH/Cortisol Ratio May Be Simple, Reliable Test to Diagnose Cushing’s Disease

The ratio between adrenocorticotropic hormone levels and cortisol levels in the blood is higher among Cushing’s disease patients than in healthy people, a new study has found, suggesting that measurement could be used to help diagnose the disease.

Also, higher values at diagnosis could predict if the disease will recur and indicate larger and more invasive tumors.

The research, “The Utility of Preoperative ACTH/Cortisol Ratio for the Diagnosis and Prognosis of Cushing’s Disease,” was published in the Journal of Neurosciences in Rural Practice.

Cushing’s syndrome (CS) is characterized by excess levels of cortisol. In patients with suspected CS, clinicians recommend testing late-night salivary or plasma (blood) cortisol, 24-hour urine-free cortisol (UC), as well as morning cortisol levels after low-dose suppression with dexamethasone, a corticosteroid.

CS may be ACTH-dependent or ACTH-independent, meaning that the high cortisol levels are caused by excess ACTH production.

Patients with CD have elevated levels of ACTH. A tumor, usually an adenoma, causes the pituitary gland to produce excess levels of ACTH, which stimulate the release of cortisol from the adrenal glands. Cortisol usually inhibits ACTH production. However, in CD patients, this feedback mechanism is absent.

Despite extensive research and clinical data, the variable and usually nonspecific signs and symptoms of CD still represent relevant challenges for diagnosis. Clinical manifestations must be associated with biochemical tests, which often have led to conflicting results.

Studies showed that although ACTH levels correlate with the size of the pituitary adenoma, the levels of cortisol do not increase as much. In fact, lower cortisol/ACTH ratios have been reported in patients with macroadenoma – which is greater than 10 millimeters in size – than in those with microadenoma, which is smaller than 10 millimeters.

Conversely, the research team hypothesized that besides their utility for determining the cause of CS, the inverse ratio – ACTH/cortisol – also may be useful for diagnosis.

The team evaluated the pretreatment plasma ACTH/cortisol levels in CS patients with excess cortisol production due to abnormal pituitary or adrenal function. Data from patients were compared with that of individuals without CS.

The study included 145 CS patients diagnosed from 2007 to 2016, 119 patients with CD, 26 with ACTH-independent CS (AICS), and 114 controls with no CS.

Patients’ clinical, laboratory, imaging, postsurgical and follow-up data were analyzed.

Results showed that patients with CD had a significantly higher basal ACTH/cortisol ratio than controls or those with AICS.

“These results showed ACTH/cortisol ratio might be a simple and useful test for the diagnosis of ACTH-dependent CS,” the researchers wrote.

Importantly, the scientists observed that a ACTH/cortisol ratio above 2.5 indicated identified 82 percent of positive CS cases and 63 percent of controls.

Overall, “an ACTH/cortisol ratio [greater than] 2.5 would be beneficial to diagnose CD together with other diagnostic tests,” they concluded.

Patients with recurrent CD showed higher pretreatment ACTH levels and ACTH/cortisol ratio than those who achieved sustained remission. CD patients also exhibited more invasive, atypical and larger tumors, as well as lower postoperative remission and higher recurrence rates.

“Higher ACTH/cortisol ratio might predict poorer prognosis,” the investigators said.


Mild Cortisol Increases Affect Cardiovascular Changes Linked to Heart Disease in Cushing’s

Increases in cortisol secretion, even if mild, induce early heart and blood vessel changes that may increase the risk for cardiovascular disease, according to Italian researchers.

The findings continue to support the role of the hormone cortisol in heart disease, and demonstrate the need for carefully monitoring cardiovascular risk in patients with high levels of the hormone, including those with Cushing’s disease.

The study, “Cardiovascular features of possible autonomous cortisol secretion in patients with adrenal incidentalomas,” was published in the European Journal of Endocrinology.

While most patients with adrenal incidentalomas don’t have symptoms, nearly half have excess cortisol production. Adrenal incidentalomas are masses in the adrenal glands discovered only when a patient undergoes imaging tests for another unrelated condition.

These asymptomatic, mild cortisol-producing cases are defined as possible autonomous cortisol secretion (pACS), according to the European Society of Endocrinology Guidelines.

Excess production of the hormone, seen in Cushing’s disease patients, is associated with increased mortality, mainly due to heart diseases. Patients with asymptomatic adrenal adenomas and mild cortisol secretion also have more cardiovascular events and generally die sooner than those with normal cortisol levels.

But little is known about the causes behind cardiac and vessel damage in these patients.

To shed light on this matter, a research team at Sapienza University of Rome evaluated the cardiovascular status of patients with pACS. This allowed them to study the impact of cortisol in the heart and blood vessels without the interference of other hormone and metabolic imbalances seen in Cushing’s disease.

The ERGO trial (NCT02611258) included 71 patients. All had been diagnosed with adrenal incidentalomas, 34 of which were pACS with mildly increased levels of the hormone and 37 were defined as nonfunctioning adenoma (NFA) — adrenal masses with normal hormone levels.

The two groups were very similar, with no significant differences in metabolic and cardiovascular risk factors. Adrenal lesions in the pACS group, however, were significantly bigger, which was linked to cortisol levels.

Looking at the heart morphology, researchers found that pACS patients had a significantly higher left ventricular mass index (LVMI), which is a well-established predictive measure of adverse cardiovascular events.

Further analysis revealed that LVMI scores were associated with levels of the hormone, suggesting it has an “independent effect of cortisol on cardiac function,” the researchers wrote.

Slightly more than half of pACS patients (53%) also had a thicker left ventricle, a feature that was seen only in 13.5% of NFA patients. The performance of the left ventricle during diastole (muscle relaxation) was also affected in 82.3% of pACS patients, compared to 35.1% in those with NFA.

Patients with pACS also had less flexible arteries, which may contribute to the development of vascular diseases.

The results show that “mild autonomous cortisol secretion can sustain early cardiac and vascular remodeling” in patients who appear apparently healthy, the researchers said.

“The morphological and functional cardiovascular changes observed in pACS underline the need for further studies to correctly define the long-term management of this relatively common condition,” they added.


Steroid Medication for Nasal Obstruction in Infants May Cause Cushing’s Syndrome

Intranasal steroid drops used to treat nasal obstruction may cause Cushing’s syndrome and adrenal insufficiency in infants, a case study of two patients suggests.

The study, “Iatrogenic Cushing’s syndrome and adrenal insufficiency in infants on intranasal dexamethasone drops for nasal obstruction – Case series and literature review,” was published in the International Journal of Pediatric Otorhinolaryngology.

Children with nasal obstruction may have severe delays in development and can face life-threatening complications later in life such as obstructive sleep apnea and cardiopulmonary problems.

While intranasal steroid drops have become increasingly popular as a substitute for surgery, they can have adverse effects. In addition to suppressing the immune system and changing metabolism, high levels of corticosteroids in the blood may cause Cushing’s syndrome.

Researchers at Weill Cornell Medical College presented two cases of adrenal gland insufficiency and Cushing’s syndrome caused by intranasal dexamethasone drops. Dexamethasone is a type of corticosteroid medication.

First, they described the case of a 3-month-old boy who was taken to the hospital following a life-threatening episode at home after feeding. A physical evaluation revealed nasal congestion with no additional anatomic abnormalities.

Treatment with nasal dexamethasone drops three times a day improved his breathing. While the dosage was later decreased to three drops once daily, a congestion episode led the mother to increase the dose back to the initial recommendation.

After seven weeks of treatment, the boy was noted to have facial puffiness, leading to an endocrine evaluation that revealed low cortisol levels. The dose was eventually reduced, and the boy’s cortisol levels returned to normal after several months.

The second case was a 6-week-old boy with a history of chronic congestion and difficulty feeding. He had severe nasal obstruction and required intubation due to respiratory distress. A nasal exam revealed damaged mucosa with severe nasal cavity narrowing, and he began treatment with three ciprofloxacin-dexamethasone drops three times a day.

After two and a half weeks of treatment, the boy’s cortisol levels were considerably low, and adrenal insufficiency was diagnosed. The treatment dose was reduced in an attempt to improve cortisol levels, but nasal obstruction symptoms continued.

The child then underwent surgery to resolve his nasal obstruction, and the treatment with steroid drops was discontinued. While his cortisol levels subsequently improved, they continued to be low, suggesting that he may have a hormone-related disease.

Despite the benefits of steroid-based nasal drops, small infants are more sensitive to steroid compounds. In addition, nasal drops are more easily absorbed than nasal sprays, suggesting that infants taking these medications should be better controlled for side effects.

“Patients started on this therapy must be closely monitored in a multi-disciplinary fashion to ensure patient safety and optimal symptom resolution,” the researchers suggested.


Case Report Shows Rare Adrenal Tumors Associated with Cushing’s Disease

Pituitary tumors that produce too much adrenocorticotropic hormone (ACTH) have been associated with the development of rare tumors on the adrenal glands, called adrenal myelolipomas, for the first time in a case report.

The study, “Case report of a bilateral adrenal myelolipoma associated with Cushing disease,” was published in the journal Medicine.

Myelolipomas, composed of mature fat cells and blood-forming cells, are usually asymptomatic and do not produce hormones. In many cases, these tumors are detected by accident when patients undergo imaging scans for other conditions.

The cause of these tumors is unknown, but due to their benign nature, they do not spread to other parts of the body. However, they can grow up to 34 centimeters (about 13 inches), leading to tissue death and hemorrhage.

Researchers at Soon Chun Hyang University College of Medicine in Seoul, Korea, described the case of a 52-year-old man with myelolipoma possibly caused by an ACTH-secreting pituitary tumor.

During a routine checkup, researchers detected a mass in the patient’s spleen. Further abdominal evaluations identified tissue lesions in both adrenal glands consistent with myelolipoma. Besides the masses, the patient did not show any other Cushing-associated physical characteristics.

However, the patient’s ACTH levels were two times higher than the normal upper limit. Cortisol levels were also increased and unresponsive to low-dose dexamethasone treatment.

No additional lesions were found that could help explain the high ACTH and cortisol levels. But analysis of blood samples collected from the veins draining the pituitary glands revealed the right gland was producing too much ACTH, strongly suggesting Cushing’s disease.

Both the left adrenal gland and pituitary tumor were surgically removed. The samples collected during surgery confirmed the benign nature of the adrenal tumors, and the diagnosis of abnormal, ACTH-positive pituitary gland tissue.

Three days after the surgeries, hormone levels were back to normal. But a follow-up evaluation five months later again showed increased ACTH levels. Cortisol levels, however, were normal.

For the next seven years, the patient was evaluated every six months. During a five-year period, the size of the right adrenal gland was found to have grown. Imaging analysis confirmed the existence of small, new lesions in both pituitary glands.

“This case confers valuable information about the clinical course of adrenal myelolipoma associated with Cushing disease,” the researchers said. It also “supports the notion that ACTH can be associated with the development of bilateral adrenal myelolipomas.”


Dr. Charles Wilson, One of the world’s greatest neurosurgeons and pioneer of transsphenoidal pituitary surgery died at 88


The UCSF website in an obituary from Kate Vidinsky reads “He took a particular interest in pituitary disorders, those affecting the pea-sized ‘master gland’ at the base of the brain responsible for controlling the body’s hormone levels. He was a pioneer of transsphenoidal surgery – the endonasal approach for removing pituitary tumors – and performed more than 3,300 of these procedures at UCSF Medical Center.”

The New York Times in an obituary published yesterday described him as “a pioneering and virtuosic San Francisco neurosurgeon”.

Dr. Wilson died February 28, 2018.

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