Causes of Cushing’s Syndrome

Cushing’s syndrome—also referred to as hypercortisolism—is fairly rare. However, researchers have boiled down a few key causes of Cushing’s syndrome, which you’ll read about below.

The cause of Cushing’s syndrome boils down to: Your body is exposed to too much cortisol. There are a few ways that this over-exposure can happen, including taking certain medications and having a tumor on your pituitary gland or adrenal gland.

Can Taking Corticosteroids Cause Cushing’s Disease?
One particular type of medication can cause Cushing’s syndrome: corticosteroids. But rest assured: Not all steroid medications cause Cushing’s syndrome. It’s more common to develop Cushing’s syndrome from steroids you take in pill form or steroids you inject. Steroid creams and steroids you inhale are not common causes of Cushing’s syndrome.

Some steroid medications have the same effect as the hormone cortisol does when produced in your body. But as with an excessive production of cortisol in your body, taking too much corticosteroid medications can, over time, lead to Cushing’s syndrome.

It’s common for people with asthma, rheumatoid arthritis, and lupus to take corticosteroids. Prednisone (eg, Deltasone) is an example of a corticosteroid medication.

Other Cushing’s Disease Causes
Your body can over-produce cortisol or adrenocorticotropic hormone (ACTH). The pituitary gland secretes ACTH, which is in charge of stimulating the adrenal glands to produce cortisol, and the adrenal glands are responsible for releasing cortisol into the bloodstream.

Cortisol performs important tasks in your body, such as helping to maintain blood pressure and regulate how your body metabolizes proteins, fats, and carbohydrates, so it’s necessary for your body to maintain normal levels of it.

The following can cause excessive production of cortisol or ACTH, leading to Cushing’s syndrome.

  • Pituitary gland tumors: A benign (non-cancerous) tumor of the pituitary gland can secrete an excess amount of ACTH, which can cause Cushing’s syndrome. Also known as pituitary adenomas, benign tumors of the pituitary gland affect women 5 times more often than men.
  • Adrenal gland tumors: A tumor in one of your adrenal glands can lead to Cushing’s syndrome by causing too much cortisol to enter your bloodstream. Most of these tumors are non-cancerous (called adrenal adenomas).

    Cancerous adrenal tumors—called adrenocortical carcinomas—are relatively rare. These types of tumors typically cause extremely high levels of cortisol and very rapid development of symptoms.

  • Other tumors in the body: Certain tumors that develop outside the pituitary gland can also produce ACTH. When this happens, it’s known as ectopic ACTH syndrome. Ectopic means that something is in an abnormal place or position. In this case, only the pituitary gland should produce ACTH, so if there is a tumor producing ACTH and it isn’t located on the pituitary, it’s ectopic.

    It’s unusual to have a tumor that secretes ACTH outside the pituitary. These tumors are usually found in the pancreas, lungs, or thyroid, and they can be benign or malignant (cancerous).

    The most common forms of ACTH-producing tumors are small cell lung cancer, which accounts for about 13% of all lung cancer cases, and carcinoid tumors—small, slow-growing tumors that arise from hormone-producing cells in various parts of the body.

  • Familial Cushing’s syndrome: Although it’s rare, Cushing’s syndrome can develop from an inherited tendency to have tumors on one or more of your endocrine glands. Some inherited conditions, such as multiple endocrine neoplasia (MEN 1), can involve tumors that over-produce cortisol or ACTH, leading to Cushing’s syndrome.

If you think you could have Cushing’s syndrome or you have questions about the causes of Cushing’s syndrome, talk to your doctor immediately.

Written by | Reviewed by Daniel J. Toft MD, PhD, adapted from  http://www.endocrineweb.com/conditions/cushings-syndrome/cushings-syndrome-causes

Pituitary Gland: Normal Function and Assessment

Abstract

This computer-based, interactive module introduces preclinical medical students to normal pituitary function and outlines its assessment. Solid understanding of these topics is requisite to learning clinical disorders of the pituitary.

Existing resources largely target learners at earlier or later stages of training; thus, we created this resource to address needs of medical students during a first- or second-year endocrine course. A module format was selected to promote interactive, independent learning.

Two cohorts of medical students completed the 40-minute module: 172 second-year students who had completed a year of basic sciences in the traditional curriculum and 180 foundation-phase students in a three-semester combined basic and clinical sciences curriculum (due to a change in the medical school curriculum at our institution). In both instances, the module was completed before start of clinical pituitary content. A static set of PowerPoint slides accompanied the module to facilitate note taking.

Test Your Knowledge slides were inserted to ensure grasp of key terms/concepts before moving to subsequent slides. A short question-and-answer session was held following module completion to clarify points of confusion. Students rated effectiveness of the module as 4.6 out of 5, commenting on its clarity, organization, high-yield nature, and utility in preparing for clinical material.

Faculty noted greater understanding of foundational pituitary principles and more engaging discussions. The percentage of pituitary-related questions answered correctly on the midterm exam increased.

Finally, success of the pituitary module prompted development of adrenal, thyroid, and parathyroid modules that now comprise the Endocrine Organs Introduction Series in our curriculum.

Citation

Kirk D, Smith KW. Pituitary gland: normal function and assessment. MedEdPORTAL Publications. 2016;12:10430. http://dx.doi.org/10.15766/mep_2374-8265.10430

Educational Objectives

After completing this module, the learner will be able to:

  1. Describe the normal function and regulation of the pituitary gland, including names and actions of the anterior and posterior pituitary hormones.
  2. Understand the basic approach to laboratory assessment of the pituitary.
  3. Differentiate between anterior and posterior pituitary origin, function, and regulation.
  4. List the hormones produced by the pituitary gland.
  5. Discuss for each pituitary hormone: hypothalamic stimulating/inhibiting factors and their clinical uses, basic physiologic function, and regulation (feedback loop).
  6. Describe factors that affect growth hormone levels.
  7. Understand the tests for growth hormone excess and deficiency.
  8. Define a primary versus secondary endocrine disorder.

Keywords

  • Endocrine, Endocrinology, Pituitary, Module, Preclinical Medical Education

More information at https://www.mededportal.org/publication/10430

Six controversial issues on subclinical Cushing’s syndrome

Abstract

Subclinical Cushing’s syndrome is a condition of hypercortisolism in the absence of signs specific of overt cortisol excess, and it is associated with an increased risk of diabetes, hypertension, fragility fractures, cardiovascular events and mortality.

The subclinical Cushing’s syndrome is not rare, being estimated to be between 0.2–2 % in the adult population. Despite the huge number of studies that have been published in the recent years, several issues remain controversial for the subclinical Cushing’s syndrome screening, diagnosis and treatment.

The Altogether to Beat Cushing’s syndrome Group was founded in 2012 for bringing together the leading Italian experts in the hypercortisolism-related diseases. This document represents the Altogether to Beat Cushing’s syndrome viewpoint regarding the following controversial issues on Subclinical Cushing’s syndrome (SCS):

(1) Who has to be screened for subclinical Cushing’s syndrome?
(2) How to screen the populations at risk?
(3) How to diagnose subclinical Cushing’s syndrome in patients with an adrenal incidentaloma?
(4) Which consequence of subclinical Cushing’s syndrome has to be searched for?
(5) How to address the therapy of choice in AI patients with subclinical Cushing’s syndrome?
(6) How to follow-up adrenal incidentaloma patients with subclinical Cushing’s syndrome surgically or conservatively treated?

Notwithstanding the fact that most studies that faced these points may have several biases (e.g., retrospective design, small sample size, different criteria for the subclinical Cushing’s syndrome diagnosis), we believe that the literature evidence is sufficient to affirm that the subclinical Cushing’s syndrome condition is not harmless and that the currently available diagnostic tools are reliable for identifying the majority of individuals with subclinical Cushing’s syndrome.

Keywords

Subclinical hypercortisolism, Adrenal incidentalomas, Hypertension, Diabetes, Osteoporosis

Patients with ARMC5 mutations: The NIH clinical experience

Screenshot 2016-05-27 13.12.55

 

Adrenal Disorders

R Correa, M Zilbermint, A Demidowich, F Faucz, A Berthon, J Bertherat, M Lodish, C Stratakis

Summary: Researchers conducted this study to describe the different phenotypical characteristics of patients with armadillo repeat containing 5 (ARMC5) mutations, located in 16p11.2 and a likely tumor-suppressor gene. They determined that patients with bilateral adrenal enlargement, found on imaging tests, should be screened for ARMC5 mutations, which are associated with subclinical Cushing’s syndrome (CS) and primary hyperaldosteronism (PA).

Methods:

  • Researchers identified 20 patients with ARMC5 mutations (germline and/or somatic) who were enrolled in a National Institutes of Health (NIH) protocol.
  • They obtained sociodemographic, clinical, laboratory, and radiological data for all participants.

Results:

  • Three families (with a total of 8 patients) were identified with ARMC5 germline mutations; the rest of the patients (13/20) had sporadic mutations.
  • The male to female ratio was 1.2:1; mean age was 48 years and 60% of patients were African American.
  • Forty percent of patients were diagnosed with CS, 20% with subclinical CS, 30% with hyperaldosteronism, and 10% had no diagnosis.
  • The mean serum cortisol (8 am) and Urinary Free Cortisol were 13.1 mcg/dl and 77 mcg/24 hours, respectively.
  • Nearly all patients (95%) had bilateral adrenal enlargement found on CT or MRI.
  • Patients underwent the following treatments: Bilateral adrenalectomy (45%), unilateral adrenalectomy (25%), medical treatment (20%), and no treatment (10%).
  • ARMC5 mutations are associated with primary macronodular adrenal hyperplasia (PMAH) and are also seen in patients with PA, especially among African Americans.

From http://www.mdlinx.com/endocrinology/conference-abstract.cfm/ZZ37C4C5D3BF1A4FAE9C479A696660535B/57884/?utm_source=confcoveragenl&utm_medium=newsletter&utm_content=abstract-list&utm_campaign=abstract-AACE2016&nonus=0

Resolution of the physical features of Cushing’s syndrome in a patient with a cortisol secreting adrenocortical adenoma after unilateral adrenalectomy

A 37-year-old woman developed clinical manifestations of Cushing’s syndrome over a span of 2 years. Physical examination revealed features that best describe Cushing’s syndrome, such as wide purple striae (>1 cm) over the abdomen, facial plethora and easy bruisability.1  Other features observed were hypertension, moon facies, acne, a dorsocervical fat pad, central obesity and dyslipidaemia.

The diagnosis of hypercortisolism was confirmed using a 1 mg overnight dexamethasone suppression test (19.7 ng/dL, N: <1.8) and 24 h urine free cortisol (185.9 μg/24 h, N: 3.5–45). A suppressed adrenocorticotropic hormone (ACTH) level (4 pg/mL, N: 5–20) and a lack of hyperpigmentation suggested ACTH-independent Cushing’s syndrome. Further work up using CT with contrast of the adrenals showed a 2.4×2.3×2.4 cm right adrenal mass. The patient then underwent laparoscopic adrenalectomy of the right adrenal gland. Steroids was started postoperatively and tapered over time. Histopathology results were consistent with an adrenocortical adenoma (2.5 cm widest dimension). Six months after surgery, there was resolution of the physical features, weight loss and improvement in blood pressure.

Figure 1 is a serial photograph of the physical features seen in Cushing’s syndrome, such as moon facies, a dorsocervical fat pad and wide purple striae, taken preoperatively, and at 3 and 6 months after surgery. With treatment, physical and biochemical changes of Cushing’s syndrome both resolve through time.2 The time course of the resolution of these changes, however, is varied.2 ,3 We observed that the physical features were ameliorated at 3 months and resolved at 6 months.

Learning points

  • Physicians as well as patients should be aware that improvement of the features of Cushing’s syndrome after treatment does not occur immediately.

  • Dramatic resolution of the physical features of Cushing’s syndrome, however, can be observed as early as 6 months after surgery.

Figure 1

Physical features of Cushing’s syndrome (top to bottom: moon facies, a dorsocervical fat pad and wide purple striae (>1 cm) over the abdomen) documented before surgery, and at 3 and 6 months after surgery.

Footnotes

  • Twitter Follow John Paul Quisumbing at @jpquisumbingmd

  • Contributors JPMQ worked up the case and wrote the case report. MASS reviewed the case report and critically appraised it. JPMQ incorporated his suggestions.

  • Competing interests None declared.

  • Patient consent Obtained.

  • Provenance and peer review Not commissioned; externally peer reviewed.

References

From http://casereports.bmj.com/content/2016/bcr-2016-215693.short?rss=1