Patients Undergoing Adrenalectomy Should Receive Steroid Substitutive Therapy

All patients who undergo removal of one adrenal gland due to Cushing’s syndrome (CS) or adrenal incidentaloma (AI, adrenal tumors discovered incidentally) should receive a steroid substitutive therapy, a new study shows.

The study, “Predictability of hypoadrenalism occurrence and duration after adrenalectomy for ACTH‐independent hypercortisolism,” was published in the Journal of Endocrinological Investigation.

CS is a rare disease, but subclinical hypercortisolism, an asymptomatic condition characterized by mild cortisol excess, has a much higher prevalence. In fact, subclinical hypercortisolism, is present in up to 20 percent of patients with AI.

The hypothalamic-pituitary-adrenal axis (HPA axis) is composed of the hypothalamus, which releases corticotropin-releasing hormone (CRH) that acts on the pituitary to release adrenocorticotropic hormone (ACTH), that in turn acts on the adrenal gland to release cortisol.

To avoid excess cortisol production, high cortisol levels tell the hypothalamus and the pituitary to stop producing CRH and ACTH, respectively. Therefore, as CS and AI are characterized by high levels of cortisol, there is suppression of the HPA axis.

As the adrenal gland is responsible for the production of cortisol, patients might need steroid substitutive therapy after surgical removal of AI. Indeed, because of HPA axis suppression, some patients have low cortisol levels after such surgeries – clinically known as post-surgical hypocortisolism (PSH), which can be damaging to the patient.

While some researchers suggest that steroid replacement therapy should be given only to some patients, others recommend it should be given to all who undergo adrenalectomy (surgical removal of the adrenal gland).

Some studies have shown that the severity of hypercortisolism, as well as the degree of HPA axis suppression and treatment with ketoconazole pre-surgery in CS patients, are associated with a longer duration of PSH.

Until now, however, there have been only a few studies to guide in predicting the occurrence and duration of PSH. Therefore, researchers conducted a study to determine whether HPA axis activity, determined by levels of ACTH and cortisol, could predict the occurrence and duration of PSH in patients who undergo an adrenalectomy.

Researchers studied 80 patients who underwent adrenalectomy for either CS or AI. Prior to the surgery, researchers measured levels of ACTH, urinary free cortisol (UFC), and serum cortisol after 1 mg dexamethasone suppression test (1 mg-DST).

After the surgery, all patients were placed on steroid replacement therapy and PSH was determined after two months. For those with PSH, levels of cortisol were determined every six months for at least four years.

Results showed that PSH occurred in 82.4 percent of CS patients and 46 percent of AI patients. PSH lasted for longer than 18 months in 50 percent of CS and 30 percent of AI patients. Furthermore, it lasted longer than 36 months for 35.7 percent of CS patients.

In all patients, PSH was predicted by pre-surgery cortisol levels after the 1 mg-DST, but with less than 70 percent accuracy.

In AI patients, a shorter-than-12-month duration of PSH was not predicted by any HPA parameter, but was significantly predicted by an absence of pre-surgery diagnosis of subclinical hypercortisolism.

So, this study did not find any parameters that could significantly predict with high sensitivity and specificity the development or duration of PSH in all patients undergoing adrenalectomy.

Consequently, the authors concluded that “the PSH occurrence and its duration are hardly predictable before surgery. All patients undergoing unilateral adrenalectomy should receive a steroid substitutive therapy.”

From https://cushingsdiseasenews.com/2017/12/08/therapy-cushings-patients-adrenalectomy/

Desmopressin is Promising Alternative in Diagnosing Cushing’s Disease

Bilateral inferior petrosal sinus sampling (IPSS) — a procedure that uses desmopressin to determine levels of ACTH hormone from veins that drain from the pituitary gland, is a sensitive way to diagnose patients with Cushing’s disease and find tumors, a Chinese study shows.

The study, “Tumour Lateralization in Cushing’s disease by Inferior Petrosal Sinus Sampling with desmopressin,” appeared in the journal Clinical Endocrinology.

Cushing’s disease is characterized by excessive production of the adrenocorticotropin hormone (ACTH) caused by a tumor in the pituitary gland. ACTH is the hormone that causes the adrenal glands to produce cortisol.

Currently, pituitary imaging is insufficient to confirm a Cushing’s diagnosis. This is because 70 percent of pituitary adenomas in Cushing’s are microadenomas, which are physically very small. As a result, 40 percent of Cushing’s patients are reported as being healthy.

This means that a Cushing’s diagnosis requires a combination of techniques including clinical symptoms, imaging methods and endocrinological assays that include measures of serum cortisol and ACTH levels.

IPSS determines ACTH levels from veins that drain from the pituitary gland. ACTH levels are then compared to ACTH levels in blood. Higher levels in the pituitary gland indicate a pituitary tumor.

IPSS can also be used to determine tumor lateralization, which refers to which side of the pituitary gland the tumor is located on. The test is 69 percent accurate.

Doctors administer IPSS along with corticotropin-releasing hormone (CRH) stimulation. IPSS with CRH is considered the gold standard for preoperative diagnosis of Cushing’s, with a diagnostic sensitivity (or true positive rate) of 95 percent and specificity (or true negative rate) of 90 to 95 percent. Unfortunately, the high cost and limited availability of CRH make it impractical for many patients.

Desmopressin has been used to replace CRH to stimulate ACTH secretion for IPSS, and prior studies have shown that desmopressin’s sensitivity is comparable to that of CRH.

Researchers at Peking Union Medical College in Beijing conducted a retrospective analysis of their experience using desmopressin-stimulated IPSS to determine its diagnostic value for Cushing’s and its predictive value for tumor lateralization.

Researchers analyzed 91 Cushing’s patients who either had negative findings on the MRI imaging of the pituitary or negative high-dose dexamethasone suppression tests, which is another method of evaluation. All patients underwent IPSS with desmopressin, followed by pituitary surgery to extract the tumor.

Of the 91 patients tested, 90 patients had confirmed Cushing’s. And of these, 89 had positive IPSS findings, which led to a sensitivity of 98.9 percent for this test. One patient out of 91 who did not have Cushing’s also underwent this test, which led to a negative IPSS result and a specificity of 100 percent.

Researchers also determined tumor lateralization in patients who were ultimately diagnosed with Cushing’s and underwent surgery. Results of the IPSS showed a 72.5 percent concordance between the results from the IPSS and the surgery.

Therefore, IPSS with desmopressin is a comparable approach to IPSS with CRH for the diagnosis of Cushing’s. It also demonstrates moderate accuracy in determining the location of tumors.

“Like many medical centers in China, we currently have no supply of CRH, while desmopressin is readily available,” researchers concluded. “Moreover, desmopressin is cheaper than CRH. As our data and other studies indicate, IPSS with desmopressin yielded comparable outcomes to IPSS with CRH. Therefore, desmopressin-stimulated IPSS might serve as a possible alternative to CRH-stimulated IPSS.”

From https://cushingsdiseasenews.com/2017/11/14/ipss-desmopressin-alternative-method-diagnosis-cushings-disease/

Rare neuroendocrine tumours may be misdiagnosed as Cushing’s disease

By Eleanor McDermid, Senior medwireNews Reporter

Ectopic tumours secreting corticotropin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) are very rare in children and can result in a misdiagnosis of Cushing’s disease (CD), say researchers.

Three of the patients in the reported case series had pituitary hyperplasia and underwent transsphenoidal surgery for apparent CD before the tumour that was actually causing their symptoms was located. The hyperplasia was probably caused by release of CRH from the ectopic tumour, which stimulated the pituitary gland, giving the impression of an ACTH-secreting pituitary adenoma, explain Maya Lodish (National Institutes of Health, Bethesda, Maryland, USA) and study co-authors.

These three patients were part of a series of seven, which Lodish et al describe as “a relatively large number of patients, considering the infrequency of this disease.”

The patients were aged between 1.8 and 21.3 years. Three had neuroendocrine tumours located in the pancreas ranging in size from 1.4 to 7.0 cm, two had thymic carcinoids ranging from 6.0 mm to 11.5 cm, one patient had a 12.0 cm tumour in the liver and one had a 1.3 cm bronchogenic carcinoid tumour of the right pulmonary lobe.

Four of the patients had metastatic disease and, during up to 57 months of follow-up, three died of metastatic disease or associated complications and two patients had recurrent disease.

“Our series demonstrates that these are aggressive tumors with a high mortality rate,” write the researchers in the Journal of Clinical Endocrinology & Metabolism. “It is important to follow the appropriate work up, regarding both biochemical and imaging tests, which can lead to the correct diagnosis and to the most beneficial therapeutic approach.”

The team found the CRH stimulation test to be helpful, noting, for example, that none of the patients had a rise in cortisol that was consistent with CD, with all patients showing smaller responses ranging from 2% to 15%. Likewise, just one patient had an ACTH rise higher than 35% on CRH administration, and four patients had a “flat” response, which has previously been associated with ectopic neuroendocrine tumours.

Of note, six patients had normal or high plasma CRH levels, despite all having high cortisol levels, which would be expected to result in undetectable plasma CRH due to negative feedback, implying another source of CRH production. Five patients had blunted diurnal variation of both cortisol and ACTH levels consistent with Cushing’s syndrome.

The patients also underwent a variety of imaging procedures to identify the source of ACTH/CRH production, some of which, such as octreotide scans, are specialist and not available in most hospitals, the researchers note, potentially contributing to inappropriate diagnosis and management.

From http://www.news-medical.net/news/20141030/Rare-neuroendocrine-tumours-may-be-misdiagnosed-as-Cushinge28099s-disease.aspx

Cushing’s Disease – Rare Disease Quick Facts

cushings-diagnosis

 

 

Cushing’s disease is a rare condition due to excess cortisol levels that result from a pituitary tumor secreting adrenocorticotropic hormone (ACTH), which stimulates cortisol secretion.  Cushing’s disease should not be confused with Cushing’s syndrome which is increased cortisol levels but that increase can be due to any number of factors. However, Cushing’s disease is the most common form of Cushing’s syndrome.

Symptoms

The symptoms related to Cushing’s disease and Cushing’s syndrome are the same, since both are related to an excess of cortisol. Also, symptoms vary extensively among patients and that, with the inherent fluctuation in hormone levels make it difficult to diagnosis both conditions.

Changes in physical characteristics of the body

  • Fullness and rounding of the face
  • Added fat on back of neck (so-called “buffalo hump”)
  • Easy bruising
  • Purplish stretch marks on the abdomen (abdominal striae)
  • Excessive weight gain, especially in abdominal region
  • Red cheeks
  • Excess hair growth on the face, neck, chest, abdomen and thighs

Changes in physiology/psychology

  • Generalized weakness and fatigue
  • Menstrual disorder
  • Decreased fertility and/or sex drive
  • High blood pressure that is often difficult to treat
  • Diabetes mellitus
  • Mood and behavior disorders

Diagnosis

The early stages of Cushing’s disease may be difficult to recognize. However, if it is suspected, diagnosis is generally a 2 stage process. First to determine if cortisol levels are high, and if so, why they are high.

Tests to confirm high cortisol levels:

  • 24-hour urine cortisol
  • Dexamethasone suppression test (low dose)

Tests to determine cause:

  • Blood ACTH level
  • Brain MRI
  • Corticotropin-releasing hormone test
  • Dexamethasone suppression test (high dose)
  • Petrosal sinus sampling

Treatment

Surgery

  • Most patients with Cushing’s disease undergo surgery to remove the pituitary adenoma offers.
  • If the tumor is isolated to the pituitary, cure rates of 80-85% are common.
  • If the tumor has spread to nearby organs, cure rates of 50-55% are common.

Medicine (approved orphan drugs)

Signifor (pasireotide)

  • Approved for patients with Cushing’s disease for whom pituitary is not an option or surgery has been ineffective.
  • Signifor is a somatostatin receptor agonist that leads to inhibition of ACTY secretion (and subsequently decreased cortisol levels).

Korlym (mifepristone)

  • Approved for patients with Cushing’s syndrome who have type 2 diabetes or glucose intolerance and have failed surgery (or not candidates for surgery).
  • Korlym is a glucocorticoid receptor antagonist which in turn blocks the effects of the high levels of cortisol in the body. Korlym is used to treat high glucose levels due to elevated cortisol.

Medicines used but not indicated for Cushing’s disease include

Mitoden

ketoconazole

Metyrapone

Etomidate

Radiation

  • Radiation therapy may be used in some patients and can be very effective in controlling the growth of these tumors.

Prognosis

In most cases, treatment can cure Cushing’s disease. If not treated properly, the chronic hypercortisolism can lead to excess morbidity and mortality due to increased cardiovascular and other risk factors.

For more information

National Library of Medicine, National Institute of Health

Cushing’s Disease Information (provided by Novartis Pharmaceuticals)

 

Images courtesy of the open access journal Orhanet Journal for Rare Diseases.  Castinetti et al. Orphanet J Rare Dis. 2012 7:41   doi:10.1186/1750-1172-7-41

– See more at: http://www.raredr.com/front-page-medicine/articles/cushings-disease-rare-disease-quick-facts-0

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