Cushing’s Syndrome

The Seven Dwarves of Cushing's

 

Posted Oct. 1st, 2015 by

Q: Would you please explain Cushing’s disease. How is it diagnosed? What are the symptoms?

A: Cushing syndrome results from excess levels of the hormone cortisol. It is produced in various glands, usually the adrenal that is situated above the kidneys on both sides, and the pituitary gland, which is in the centre of the brain.

Cortisol also regulates the way fats, carbohydrates and proteins are turned into usable forms of energy. These glands produce other hormones that affect things such as blood pressure and the body’s response to stress.

Cortisol may be added from outside the body by taking medications such as prednisone, often used for the control of chronic inflammatory or autoimmune diseases like lupus or rheumatoid arthritis.

Prednisone is also used for the treatment of acute illnesses such as severe allergies. Poison ivy is often treated this way.

Women in the last three months of pregnancy also have increased blood levels of cortisol and may temporarily display some of symptoms of Cushing’s syndrome.

Any problem with the pituitary gland, the nearby hypothalamus in the brain or adrenals can lead to Cushing’s syndrome. The most common is a benign tumour of the pituitary gland known as a pituitary adenoma.

This type of tumour may produce an excessive amount of a stimulating hormone known as ACTH, which in turn activates the hormones in the adrenal glands. On rare occasions, some types of lung or thyroid cancer can also behave in a similar way.

The most obvious sign of Cushing’s disease is marked weight gain, mostly in the abdomen, face and neck, while the arms and legs remain relatively thin.

As the skin in these areas becomes thinner, there may be purple coloured stripes or stretch marks. Women may also lose their periods and grow facial or body hair.

Blood pressure is usually high and sufferers feel weak and tired.

Cushing’s disease is diagnosed by measuring the amount of cortisol in a person’s urine during a 24 hour period.

If there is a tumour it will require surgical removal. If Cushing’s syndrome is a result of prescribed medication, the dosage can be reduced gradually or another type of medication can be tried. Prednisone must never be suddenly discontinued or the person’s blood pressure could drop dramatically, which could be serious and potentially fatal.

Clare Rowson is a retired medical doctor in Belleville, Ont. Contact: health@producer.com

From http://www.producer.com/2015/10/cushings-syndrome/

Endocrine Society Releases Guidelines on Treatment of Cushing’s Syndrome

To lessen the risk for comorbidity and death, the Endocrine Society’s newly published guidelines on the treatment of Cushing’s syndrome focus on surgical resection of the causal tumor with the goal of normalizing cortisol levels. Furthermore, there is increased emphasis on individualizing treatment options when choosing a second-line treatment.

In July 2015, the Endocrine Society published treatment guidelines to assist endocrinologists in appropriately initiating treatment or referring patients with Cushing’s syndrome to treatment. A task force of experts compiled evidence from systematic reviews and graded the strength of the recommendations.

“We hope that it will lead to improved treatment of comorbidities both before and after definitive treatment of the syndrome, and to increased individualization of patient treatment,” said chair of the task force Lynnette Nieman, MD, who is chief of the Endocrinology Consultation Service at the National Institutes of Health Clinical Center.

“There are two new drugs that were approved in 2012, and so I think that is what prompted the review. Still, medications are not the first line of treatment, but we have some new therapeutic options, and I think the idea was to help people understand where to use them,” Julie Sharpless, MD, assistant professor and director of the UNC Multidisciplinary Pituitary Adenoma Program, told Endocrinology Advisor.

“The primary treatment is surgical resection of the causal tumor(s). If that cannot be done (because the tumor is occult or metastatic) or is not successful, then the choice of secondary treatment should be individualized to the patient. The comorbidities of Cushing’s syndrome, for example hypertension and diabetes, should be treated separately as well,” Nieman said.

For example, the guidelines recommend surgical removal of the causative lesion, with the exception of cases which are unlikely to cause a drop in glucocorticoids or in patients who are not surgical candidates.

Likewise, in patients with benign unilateral adrenal adenoma, adrenalectomy by an experienced surgeon has a high rate of cure in children and adults. Because of the poor prognosis associated with adrenal carcinoma, the guidelines highlight the need for complete resection and possibly medical treatment to stabilize cortisol levels.

Other first-line treatment options include recommending surgical resection of ectopic ACTH-secreting tumors; referring to an experienced pituitary surgeon for transsphenoidal selective adenomectomy; treatments to block hormone receptors in bilateral micronodular adrenal hyperplasia; and surgical removal in bilateral adrenal disorders.

The elevated mortality rate seen in patients with Cushing’s syndrome is due to infection, venous thrombosis and cardiovascular disease (CVD). Appropriately lowering cortisol levels improves hypertension, insulin resistance, dyslipidemia and obesity in patients with Cushing’s syndrome. Therefore, the guidelines highlight the need for restoring cortisol levels and treating the associated comorbidities.

Nevertheless, the task force specifically recommends against treatment without an established diagnosis or when there are no signs of Cushing’s syndrome and hypothalamic-pituitary-adrenal laboratory studies are borderline.

In patients who are not surgical candidates or in cases of noncurative resection, the decision on whether to consider second-line treatment options such as medical therapy, radiation, bilateral adrenalectomy or repeat transsphenoidal surgery should be based on several factors. For instance, the guidelines recommend taking into consideration location and size of the tumor, patient desires, goals of treatment and level of biochemical control.

The guidelines note medical therapy should be based on cost, efficacy and individualization of treatment. Endocrinologists can approach medical therapy with a goal of establishing normal cortisol levels or reducing cortisol levels to very low levels and replacing to achieve desired levels.

Remission in Cushing’s syndrome is associated with notable improvement; however, long-term follow-up is recommended for osteoporosis, CVD and psychiatric conditions.

After treatment, patients may experience reductions in weight, blood pressure, lipids and glucose levels that may allow reduction or discontinuation of medications. Even so, patients with a history of Cushing’s syndrome tend to have higher rates of hypertension, hyperlipidemia and diabetes. Likewise, rates of myocardial infarction are higher in this population, further emphasizing the need for treatment and management of diabetes and hypertension.

Sharpless highlighted that Cushing’s syndrome is rare.

“There are multiple studies that have shown that patients do better when they are treated in a specialty center where people see a lot of cases of this. So in that sense, treatment is not usually going to fall to the general practitioner,” she said.

She continued that the guidelines are helpful and provide guidance to endocrinologist who “can’t readily refer their patient to a pituitary center.”

Sharpless went on to describe the multidisciplinary care involved in Cushing’s syndrome including endocrinologists, neurosurgeons, radiologists, counselors and radiation oncologist.

“When the care is complicated, you want to ensure all of your providers have reviewed your case together and figured out the best plan.”

The guidelines were co-sponsored by the European Society of Endocrinology. Nieman received salary support for her work on the manuscript from the Intramural Research Program of the Eunice Kennedy Shiver Institute of Child Health and Human Development. Members of the task force reported multiple disclosures.

Reference

  1. Nieman LK et al. J Clin Endocrinol Metab. 2015;100(8):2807-2831.

From http://www.endocrinologyadvisor.com/adrenal/cushings-syndrome-endocrine-society-guidelines/article/434307/

Lowest cortisol levels found in women with overweight, mild obesity

Women with overweight and class I obesity appear to have the lowest cortisol levels, while more significant obesity appears to be associated with higher cortisol levels, according to recent findings.

In the cross-sectional study, Karen K. Miller, MD, of Massachusetts General Hospital, and colleagues evaluated 60 premenopausal women aged 18 to 45 years: 28 with overweight or obesity, 18 with anorexia nervosa and 21 healthy controls at normal weight. Overweight was defined as BMI 25 to 29.9 kg/m2, and obesity was classified as class I (30-34.9 kg/m2) and class II (35-39 kg/m2).

Anorexia nervosa was classified based on DSM-IV criteria, which includes extreme fear of weight gain, body image dysmorphia, weight that is 85% of ideal body weight and cessation of menstruation for 3 consecutive months. Participants were asked to collect 24-hour urine samples, in addition to 11 p.m. and 7 a.m. salivary samples within 1 week of an inpatient hospital visit. For each sample, researchers assessed creatinine clearance, and urinary free cortisol/creatinine clearance was calculated for each specimen to account for the decreased creatinine and filtered cortisol linked to anorexia nervosa.

During the inpatient visit, participants underwent placement of an IV catheter and fasting blood was sampled every 20 minutes from 8 p.m. to 8 a.m. Fasting cortisol and cortisol binding globulin concentrations were measured at 8 a.m. Participants were asked to take 5 g of oral dexamethasone every 6 hours for 48 hours to decrease endogenous disparities in cortisol levels.

The researchers found that with the exception of dexamethasone-suppression-CRH testing, all cortisol measures exhibited a U-shaped association with BMI, most notably urinary free cortisol/creatinine clearance (P = .0004) and mean overnight serum cortisol (P < .0001).

The lowest cortisol levels were seen in the overweight-class I obesity range, and these were also associated with visceral fat tissue and total fat mass. Participants with anorexia nervosa had higher mean cortisol levels than participants with overweight or obesity. Attenuated inverse relationships were seen between lean mass and some measures of cortisol, and most measures of cortisol were inversely related to posterior-anterior spine and total hip bone mineral density.

According to the researchers, these findings have not determined the precise nature of the relationship between cortisolemia, hypothalamic-pituitary-adrenal activation and adiposity.

“The [hypothalamic-pituitary-adrenal] axis activation associated with obesity and excess adiposity raises the question of whether hypercortisolemia contributes to increased adiposity in the setting of caloric excess, whether increased adiposity drives [hypothalamic-pituitary adrenal] activation, or whether the relationship between hypercortisolemia and adiposity is bidirectional,” the researchers wrote. – by Jennifer Byrne

Disclosure: The researchers report no relevant financial disclosures.

From http://www.healio.com/endocrinology/obesity/news/online/%7B73cac1c4-af30-4f24-89e3-86f50d05aaa2%7D/lowest-cortisol-levels-found-in-women-with-overweight-mild-obesity

“My feet are killing me!” An unusual presentation of Cushing’s syndrome

Adverse effects of steroid excess on bone metabolism are well established but presentation of Cushing’s syndrome with metabolic bone disease is reported to be uncommon. We describe a case of Cushing’s syndrome presenting with pathological fractures probably present for 8 years before diagnosis.

A 33 year old nurse first sustained spontaneous stress fractures of her metatarsals in 1994, with repeated fractures occurring up to 2002. In 2001 she developed hypertension, acute lumbar back pain and gained weight.

In 2002 she was admitted to hospital with chest/back pain. Lumbar spine X-ray showed new fracture of L3,old fractures of L4/5,with fractured ribs on CXR. Isotope bone scan revealed multiple hot spots. MRI showed collapse of T8 with features consistent with malignant disease. The primary malignancy was sought and a left-sided 1.5 centimetre thyroid nodule detected.

Suspicious cytology prompted thyroid lobectomy revealing follicular variant of papillary carcinoma. T8 biopsy revealed chronic infection with Propionobacteria rather than metastatic carcinoma. Despite antibiotic therapy further spontaneous vertebral fractures developed. Bone densitometry revealed Z scores of minus 2.4 at L2-4, minus 2.5 and 2.9 at the hips.

Referral to our centre prompted investigations for Cushing’s syndrome. Serum potassium was 4.1 millimols per litre, androgens, calcitonin and urinary catecholamines all normal. TSH was suppressed by T4 therapy. Urinary free cortisol values were raised,(563-959 nanomols per 24hours) with loss of diurnal rhythm in cortisol secretion (9am 429-586,midnight 397-431 nanomols per litre)and no suppression on low or high dose dexamethasone. Abdominal CT showed a 3.5 centimetre adrenal mass. These findings were consistent with adrenal dependent Cushing’s syndrome. Risedronate and metyrapone were commenced before adrenalectomy, completion thyroidectomy and ablative radioiodine.
Comment: Cushing’s syndrome may present with spontaneous fractures in both axial and appendicular skeleton in the absence of marked clinical features. This case demonstrates the importance of thorough investigation of unexplained fractures.

LM Albon, JD Rippin & JA Franklyn

From http://www.endocrine-abstracts.org/ea/0005/ea0005p26.htm

Recurrent sellar mass after resection of pituitary macroadenoma

A Puerto Rican woman aged 50 years presented to an ophthalmologist with complaints of vision changes, including difficulty seeing images in her peripheral vision in both eyes and difficulty in color perception. Her medical history was significant for menopause at age 43 years, type 2 diabetes and hypertension. She had no prior history of thyroid disease, changes in her weight, dizziness or lightheadedness, headaches, galactorrhea or growth of her hands or feet.

Formal visual fields showed bitemporal superior quadrantopsia, and she was sent to the ED for further evaluation.

Imaging and laboratory tests

A pituitary protocol MRI was performed that showed a large 3 cm x 2 cm x 2.2 cm mass in the pituitary with mild osseous remodeling of the sella turcica and mass effect on the optic chiasm (Figure 1). The mass was isointense with the brain parenchyma on T1-weighted and T2-weighted images and homogeneously enhanced after IV gadolinium contrast administration.

Baseline laboratory samples drawn at 11 p.m. in the ED showed a cortisol of 16.9 µg/dL (nighttime reference range: 3-16 µg/dL), adrenocorticotropic hormone 65 pg/mL (reference range: 6-50 pg/mL), prolactin 19.4 ng/mL (reference range: 5.2-26.5 ng/mL), thyroid-stimulating hormone 1.36 µIU/mL (reference range: 0.35-4.9 µIU/mL), free thyroxine 0.9 ng/dL (reference range: 0.6-1.8 ng/dL), triiodothyronine 85 ng/dL (reference range: 83-160 ng/dL), follicle-stimulating hormone (FSH) 11.1 mIU/mL (postmenopausal reference range: 26.7- 133.4 mIU/mL) and luteinizing hormone (LH) 1.2 mIU/mL (postmenopausal reference range: 5.2-62 mIU/mL).

 

Figure 1. T1-weighted MRI images with and without contrast of the pituitary. Coronal (A) and sagittal (C) images showed a large isodense (with brain parenchyma) 3 cm x 2 cm x 2.2 cm mass (red arrow) in the sella with superior extension to the optic chiasm. After gadolinium contrast, coronal (B) and sagittal (D) images show the mass homogenously enhances consistent with a pituitary adenoma.

Images courtesy of Pavani Srimatkandada, MD.

Given the patient’s high nighttime cortisol and adrenocorticotropic hormone (ACTH) levels, she underwent an overnight dexamethasone suppression test with 1 mg dexamethasone. Her morning cortisol was appropriately suppressed to less than 1 µg/dL, excluding Cushing’s disease.

Pituitary adenoma resection

The patient was diagnosed with a nonsecreting pituitary adenoma with suprasellar extension and optic chiasm compression with visual field deficits. The macroadenoma caused an inappropriately normal LH and FSH in a postmenopausal woman consistent with hypogonadotrophic hypogonadism.

She underwent transnasal transsphenoidal resection of the nonsecreting pituitary adenoma. The dural defect caused by the surgery was patched with an abdominal fat graft with a DuraSeal dura patch. A postoperative MRI showed complete resection of the adenoma with no evaluable tumor in the sella (Figure 2). Her postoperative course was complicated by transient diabetes insipidus requiring intermittent desmopressin; however, this resolved before her discharge from the hospital.

Figure 2. T1-weighted MRI images with contrast. Coronal views before (A) and after (B) transphenoidal tumor resection show complete resolution of the enhancing pituitary mass (A; red arrow) that is replaced with a new hypodense mass in the sella (B; yellow arrow). This mass is filled with cerebrospinal fluid with a residual rim of enhancing tissue. This is consistent with the development of a pseudomeningocele in the sella.

 

Postoperative testing confirmed secondary deficiency of the adrenal, thyroid and ovarian axes requiring hormone therapy. The patient had stable temporal hemianopia in the left eye with improved vision in the right eye.

Recurrent mass detected

One year after surgery, during a routine follow-up appointment, the patient reported no dizziness, lightheadedness, worsening vision changes, rhinorrhea or headache. She had a follow-up MRI of the brain with and without contrast, which showed the interval appearance of a mass in the sella that extended from the sphenoid sinus into the sella and came in contact with the optic nerve (Figure 3).

Figure 3. Axial MRI images of the sella after resection of pituitary adenoma. On T1-weighted images the mass (red arrow) in the sella is hypodense (black) compared with the brain parenchyma. On T2-weighted images, the mass (red arrow) is hyperdense (bright) compared with the brain, consistent with fluid. Cerebrospinal fluid in the sulci on the brain surface and the vitreous fluid within the eye are also hyperintense on T2-weighted images (yellow arrows).

 

On MRI, the mass was isodense with the cerebral spinal fluid (CSF) with a residual rim of enhancing normal pituitary tissue. This appearance is consistent with the postoperative development of a pseudomeningocele and not a solid mass in the sella (Table).

Pseudomeningoceles are abnormal collections of CSF that communicate with the CSF space around the brain; these occur after brain surgery involving duraplasty (incision and repair of the dura). Unlike meningoceles, pseudomeningoceles are not completely encased by a surrounding membrane, and they communicate with the circulating CSF. Similar to CSF, a pseudomeningocele is hypodense (dark) compared with brain on T1-weighted MRI images and hyperdense (bright) on T2-weight images.

 

Pseudomeningocele treatment

Treatment may be conservative or may involve neurosurgical repair if symptomatic. Little published data addresses the development of pseudomeningoceles after transsphenoidal pituitary surgery, but this complication occasionally occurs, especially if the dural incision is large. One study noted that pseudomeningoceles are one of the most common complications after suboccipital decompression for Chiari’s malformation, but the effect of this complication is unclear.

Endocrinologists must recognize that recurrent development of pituitary masses after transsphenoidal pituitary adenoma surgery may not represent regrowth of pituitary tissue, but instead development of a meningocele/pseudomeningocele. Pseudomeningocele can be easily confirmed because this fluid collection has very different MRI characteristics than pituitary adenoma (Table). Given that patients may remain asymptomatic after the development of a pseudomeningocele, periodic MRI imaging, hormonal evaluation and ophthalmologic monitoring of visual fields are required after transsphenoidal pituitary surgery.

References:
  • Hernandez Guilabert PM. Poster No C-1330. Presented at: European Society of Radiology; March 7-11, 2013; Vienna.
  • Parker SL, et al. J Neurosurg. 2013;doi:10.3171/2013.8.JNS122106.
For more information:
  • Stephanie L. Lee, MD, PhD, ECNU, is an associate professor of medicine and associate chief, in the Section of Endocrinology, Diabetes and Nutrition at Boston Medical Center. Lee can be reached at Boston Medical Center, 88 E. Newton St., Endocrinology Evans 201, Boston, MA 02118; email: stephanie.lee@bmc.org. Lee reports no relevant financial disclosures.
  • Pavani Srimatkandada, MD, is an endocrinology fellow in the Section of Endocrinology, Diabetes and Nutrition at Boston Medical Center. Srimatkandada can be reached at Boston Medical Center, 88 E. Newton St., Endocrinology Evans 201, Boston, MA 02118. She reports no relevant financial disclosures.

From http://www.healio.com/endocrinology/thyroid/news/print/endocrine-today/%7B82430fb6-bbe4-4908-a389-447eee8cd005%7D/recurrent-sellar-mass-after-resection-of-pituitary-macroadenoma