Pituitary

ℹ️ Basics: Testing: Dex Tests

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Dexamethasone suppression test measures whether adrenocorticotrophic hormone (ACTH) secretion by the pituitary can be suppressed.

How the Test is Performed

During this test, you will receive dexamethasone. This is a strong man-made (synthetic) glucocorticoid medicine. Afterward, your blood is drawn so that the cortisol level in your blood can be measured.

There are two different types of dexamethasone suppression tests: low dose and high dose. Each type can either be done in an overnight (common) or standard (3-day) method (rare). There are different processes that may be used for either test. Examples of these are described below.

Common:

  • Low-dose overnight — You will get 1 milligram (mg) of dexamethasone at 11 p.m., and a health care provider will draw your blood the next morning at 8 a.m. for a cortisol measurement.
  • High-dose overnight — The provider will measure your cortisol on the morning of the test. Then you will receive 8 mg of dexamethasone at 11 p.m. Your blood is drawn the next morning at 8 a.m. for a cortisol measurement.

Rare:

  • Standard low-dose — Urine is collected over 3 days (stored in 24-hour collection containers) to measure cortisol. On day 2, you will get a low dose (0.5 mg) of dexamethasone by mouth every 6 hours for 48 hours.
  • Standard high-dose — Urine is collected over 3 days (stored in 24-hour collection containers) for measurement of cortisol. On day 2, you will receive a high dose (2 mg) of dexamethasone by mouth every 6 hours for 48 hours.

Read and follow the instructions carefully. The most common cause of an abnormal test result is when instructions are not followed.

How to Prepare for the Test

The provider may tell you to stop taking certain medicines that can affect the test, including:

  • Antibiotics
  • Anti-seizure drugs
  • Medicines that contain corticosteroids, such as hydrocortisone, prednisone
  • Estrogen
  • Oral birth control (contraceptives)
  • Water pills (diuretics)

How the Test will Feel

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.

Why the Test is Performed

This test is done when the provider suspects that your body is producing too much cortisol. It is done to help diagnose Cushing syndrome and identify the cause.

The low-dose test can help tell whether your body is producing too much ACTH. The high-dose test can help determine whether the problem is in the pituitary gland (Cushing disease) or from a different site in the body (ectopic).

Dexamethasone is a man-made (synthetic) steroid that binds to the same receptor as cortisol. Dexamethasone reduces ACTH release in normal people. Therefore, taking dexamethasone should reduce ACTH level and lead to a decreased cortisol level.

If your pituitary gland produces too much ACTH, you will have an abnormal response to the low-dose test. But you can have a normal response to the high-dose test.

Normal Results

Cortisol level should decrease after you receive dexamethasone.

Low dose:

  • Overnight — 8 a.m. plasma cortisol lower than 1.8 micrograms per deciliter (mcg/dL) or 50 nanomoles per liter (nmol/L)
  • Standard — Urinary free cortisol on day 3 lower than 10 micrograms per day (mcg/day) or 280 nmol/L

High dose:

  • Overnight — greater than 50% reduction in plasma cortisol
  • Standard — greater than 90% reduction in urinary free cortisol

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or may test different specimens. Talk to your doctor about the meaning of your specific test results.

What Abnormal Results Mean

An abnormal response to the low-dose test may mean that you have abnormal release of cortisol (Cushing syndrome). This could be due to:

The high-dose test can help tell a pituitary cause (Cushing disease) from other causes. An ACTH blood test may also help identify the cause of high cortisol.

Abnormal results vary based on the condition causing the problem.

Cushing syndrome caused by an adrenal tumor:

  • Low-dose test — no decrease in blood cortisol
  • ACTH level — low
  • In most cases, the high-dose test is not needed

Ectopic Cushing syndrome:

  • Low-dose test — no decrease in blood cortisol
  • ACTH level — high
  • High-dose test — no decrease in blood cortisol

Cushing syndrome caused by a pituitary tumor (Cushing disease)

  • Low-dose test — no decrease in blood cortisol
  • High-dose test — expected decrease in blood cortisol

False test results can occur due to many reasons, including different medicines, obesity, depression, and stress. False results are more common in women than men.

Most often, the dexamethasone level in the blood is measured in the morning along with the cortisol level. For the test result to be considered accurate, the dexamethasone level should be higher than 200 nanograms per deciliter (ng/dL) or 4.5 nanomoles per liter (nmol/L). Dexamethasone levels that are lower can cause a false-positive test result.

Risks

There is little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another, and from one side of the body to the other. Taking blood from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

  • Excessive bleeding
  • Fainting or feeling lightheaded
  • Multiple punctures to locate veins
  • Hematoma (blood accumulating under the skin)
  • Infection (a slight risk any time the skin is broken)

Alternative Names

DST; ACTH suppression test; Cortisol suppression test

References

Chernecky CC, Berger BJ. Dexamethasone suppression test – diagnostic. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. St Louis, MO: Elsevier Saunders; 2013:437-438.

Guber HA, Oprea M, Russell YX. Evaluation of endocrine function. In: McPherson RA, Pincus MR, eds. Henry’s Clinical Diagnosis and Management by Laboratory Methods. 24th ed. St Louis, MO: Elsevier; 2022:chap 25.

Newell-Price JDC, Auchus RJ. The adrenal cortex. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 15.

Review Date 5/13/2021

Updated by: Brent Wisse, MD, Board Certified in Metabolism/Endocrinology, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

From https://medlineplus.gov/ency/article/003694.htm

ℹ️ Basics: The Pituitary Gland: Small But Mighty

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The pituitary gland works hard to keep you healthy, doing everything from ensuring proper bone and muscle growth to helping nursing mothers produce milk for their babies. Its functionality is even more remarkable when you consider the gland is the size of a pea.

“The pituitary is commonly referred to as the ‘master’ gland because it does so many important jobs in the body,” says Karen Frankwich, MD, a board-certified endocrinologist at Mission Hospital. “Not only does the pituitary make its own hormones, but it also triggers hormone production in other glands. The pituitary is aided in its job by the hypothalamus. This part of the brain is situated above the pituitary, and sends messages to the gland on when to release or stimulate production of necessary hormones.”

These hormones include:

  • Growth hormone, for healthy bone and muscle mass
  • Thyroid-stimulating hormone, which signals the thyroid to produce its hormones that govern metabolism and the body’s nervous system, among others
  • Follicle-stimulating and luteinizing hormones for healthy reproductive systems (including ovarian egg development in women and sperm formation in men, as well as estrogen and testosterone production)
  • Prolactin, for breast milk production in nursing mothers
  • Adrenocorticotropin (ACTH), which prompts the adrenal glands to produce the stress hormone cortisol. The proper amount of cortisol helps the body adapt to stressful situations by affecting the immune and nervous systems, blood sugar levels, blood pressure and metabolism.
  • Antidiuretic (ADH), which helps the kidneys control urine levels
  • Oxytocin, which can stimulate labor in pregnant women

The work of the pituitary gland can be affected by non-cancerous tumors called adenomas. “These tumors can affect hormone production, so you have too little or too much of a certain hormone,” Dr. Frankwich says. “Larger tumors that are more than 1 centimeter, called macroadenomas, can also put pressure on the area surrounding the gland, which can lead to vision problems and headaches. Because symptoms can vary depending on the hormone that is affected by a tumor, or sometimes there are no symptoms, adenomas can be difficult to pinpoint. General symptoms can include nausea, weight loss or gain, sluggishness or weakness, and changes in menstruation for women and sex drive for men.”

If there’s a suspected tumor, a doctor will usually run tests on a patient’s blood and urine, and possibly order a brain-imaging scan. An endocrinologist can help guide a patient on the best course of treatment, which could consist of surgery, medication, radiation therapy or careful monitoring of the tumor if it hasn’t caused major disruption.

“The pituitary gland is integral to a healthy, well-functioning body in so many ways,” Dr. Frankwich says. “It may not be a major organ you think about much, but it’s important to know how it works, and how it touches on so many aspects of your health.”

Adapted from http://www.stjhs.org/HealthCalling/2016/December/The-Pituitary-Gland-Small-but-Mighty.aspx

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ℹ️ Basics: Testing: IGF-1 (Insulin-like growth factor 1)

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Aim—To contribute to the debate about whether growth hormone (GH) and insulin-like growth factor 1 (IGF-1) act independently on the growth process.

Methods—To describe growth in human and animal models of isolated IGF-1 deficiency (IGHD), such as in Laron syndrome (LS; primary IGF-1 deficiency and GH resistance) and IGF-1 gene or GH receptor gene knockout (KO) mice.

Results—Since the description of LS in 1966, 51 patients were followed, many since infancy. Newborns with LS are shorter (42–47 cm) than healthy babies (49–52 cm), suggesting that IGF-1 has some influence on intrauterine growth. Newborn mice with IGF-1 gene KO are 30% smaller. The postnatal growth rate of patients with LS is very slow, the distance from the lowest normal centile increasing progressively. If untreated, the final height is 100–136 cm for female and 109–138 cm for male patients. They have acromicia, organomicria including the brain, heart, gonads, genitalia, and retardation of skeletal maturation. The availability of biosynthetic IGF-1 since 1988 has enabled it to be administered to children with LS. It accelerated linear growth rates to 8–9 cm in the first year of treatment, compared with 10–12 cm/year during GH treatment of IGHD. The growth rate in following years was 5–6.5 cm/year.

Conclusion—IGF-1 is an important growth hormone, mediating the protein anabolic and linear growth promoting effect of pituitary GH. It has a GH independent growth stimulating effect, which with respect to cartilage cells is possibly optimised by the synergistic action with GH.

Keywords: insulin-like growth factor I, growth hormones, Laron syndrome, growth

In recent years, new technologies have enabled many advances in the so called growth hormone (GH) axis (fig 1▶). Thus, it has been found that GH secretion from the anterior pituitary is regulated not only by GH releasing hormone (GHRH) and somatostatin (GH secretion inhibiting hormone), but also by other hypothalamic peptides called GH secretagogues, which seem to act in synergism with GHRH by inhibiting somatostatin. One of these has been cloned and named Ghrelin. The interplay between GHRH and somatostatin induces a pulsatile GH secretion, which is highest during puberty. GH induces the generation of insulin-like growth factor 1 (IGF-1, also called somatomedin 1) in the liver and regulates the paracrine production of IGF-1 in many other tissues.

IGF-1

IGF-1 and IGF-2 were identified in 1957 by Salmon and Daughaday and designated “sulphation factor” by their ability to stimulate 35-sulphate incorporation into rat cartilage. Froesch et al described the non-suppressible insulin-like activity (NSILA) of two soluble serum components (NSILA I and II). In 1972, the labels sulphation factor and NSILA were replaced by the term “somatomedin”, denoting a substance under control and mediating the effects of GH. In 1976, Rinderknecht and Humbel isolated two active substances from human serum, which owing to their structural resemblance to proinsulin were renamed “insulin-like growth factor 1 and 2” (IGF-1 and 2). IGF-1 is the mediator of the anabolic and mitogenic activity of GH.

CHEMICAL STRUCTURE

The IGFs are members of a family of insulin related peptides that include relaxin and several peptides isolated from lower invertebrates. IGF-1 is a small peptide consisting of 70 amino acids with a molecular weight of 7649 Da. Similar to insulin, IGF-1 has an A and B chain connected by disulphide bonds. The C peptide region has 12 amino acids. The structural similarity to insulin explains the ability of IGF-1 to bind (with low affinity) to the insulin receptor.

THE IGF-1 GENE

The IGF-1 gene is on the long arm of chromosome 12q23–23. The human IGF-1 gene consists of six exons, including two leader exons, and has two promoters.

IGF binding proteins (IGFBPs)

In the plasma, 99% of IGFs are complexed to a family of binding proteins, which modulate the availability of free IGF-1 to the tissues. There are six binding proteins. In humans, almost 80% of circulating IGF-1 is carried by IGFBP-3, a ternary complex consisting of one molecule of IGF-1, one molecule of IGFBP-3, and one molecule of an 88 kDa protein named acid labile subunit. IGFBP-1 is regulated by insulin and IGF-1; IGFBP-3 is regulated mainly by GH but also to some degree by IGF-1.

The IGF-1 receptor

The human IGF-1 receptor (type 1 receptor) is the product of a single copy gene spanning over 100 kb of genomic DNA at the end of the long arm of chromosome 15q25–26. The gene contains 21 exons (fig 2▶) and its organisation resembles that of the structurally related insulin receptor (fig 3▶). The type 1 IGF receptor gene is expressed by almost all tissues and cell types during embryogenesis. In the liver, the organ with the highest IGF-1 ligand expression, IGF-1 receptor mRNA is almost undetectable, possibly because of the “downregulation” of the receptor by the local production of IGF-1. The type 1 IGF receptor is a heterotetramer composed of two extracellular spanning α subunits and transmembrane β subunits. The α subunits have binding sites for IGF-1 and are linked by disulphide bonds (fig 3▶). The β subunit has a short extracellular domain, a transmembrane domain, and an intracellular domain. The intracellular part contains a tyrosine kinase domain, which constitutes the signal transduction mechanism. Similar to the insulin receptor, the IGF-1 receptor undergoes ligand induced autophosphorylation. The activated IGF-1 receptor is capable of phosphorylating other tyrosine containing substrates, such as insulin receptor substrate 1 (IRS-1), and continues a cascade of enzyme activations via phosphatidylinositol-3 kinase (PI3-kinase), Grb2 (growth factor receptor bound protein 2), Syp (a phophotyrosine phosphatase), Nck (an oncogenic protein), and Shc (src homology domain protein), which associated to Grb2, activates Raf, leading to a cascade of protein kinases including Raf, mitogen activated protein (MAP) kinase, 5 G kinase, and others.

Physiology

IGF-1 is secreted by many tissues and the secretory site seems to determine its actions. Most IGF-1 is secreted by the liver and is transported to other tissues, acting as an endocrine hormone. IGF-1 is also secreted by other tissues, including cartilagenous cells, and acts locally as a paracrine hormone (fig 4▶). It is also assumed that IGF-1 can act in an autocrine manner as an oncogene. The role of IGF-1 in the metabolism of many tissues including growth has been reviewed recently.

Is IGF-1 “a” or “the” growth hormone?

The discussion on the role of IGF-1 in body growth will be based on growth in states of IGF-1 deficiency and the effects of exogenous IGF-1 administration. Experiments in nature (gene deletion or gene mutations) or experimental models in animals, such as gene knockouts, help us in this endeavour. In 1966 and 1968, we described a new type of dwarfism indistinguishable from genetic isolated GH deficiency (IGHD), but characterised by high serum GH values. Subsequent studies revealed that these patients cannot generate IGF-1.

This syndrome of GH resistance (insensitivity) was named by Elders et al as Laron dwarfism, a name subsequently changed to Laron syndrome (LS). Molecular studies revealed that the causes of GH resistance are deletions or mutations in the GH receptor gene, resulting in the failure to generate IGF-1 and a reduction in the synthesis of several other substances, including IGFBP-3. This unique model in humans has enabled the study of the differential effects of GH and IGF-1.

Growth and development in congenital (primary) IGF-1 deficiency (LS)

Our group has studied and followed 52 patients (many since birth) throughout childhood, puberty, and into adulthood. We found that newborns with LS are slightly shorter at birth (42–47 cm) than healthy babies (49–52 cm), suggesting that IGF-1 has some influence on intrauterine linear growth. This fact is enforced by the findings that already at birth, and throughout childhood, skeletal maturation is retarded, as is organ growth. These growth abnormalities include a small brain (as expressed by head circumference), a small heart (cardiomicria), and acromicria (small chin, resulting from underdevelopment of the facial bones, small hands, and small feet). IGF-1 deficiency also causes underdevelopment and weakness of the muscular system, and impairs and weakens hair and nail growth. These findings are identical to those described in IGHD. IGF-1 deficiency throughout childhood causes dwarfism (final height if untreated, 100–135 cm in female and 110–142 cm in male patients), with an abnormally high upper to lower body ratio. One patient reported from the UK was found to have a deletion of exons 4 and 5 of the IGF-1 gene and he too was found to have severe growth retardation.

Impaired growth and skeletal development in the absence of IGF-1 were confirmed in mice using knockout (KO) of the IGF-1 gene or GH receptor gene.

Knockout of the IGF-1 gene or the IGF-1 receptor gene reduces the size of mice by 40–45%. Lack of the IGF-1 receptor is lethal at birth in mice owing to respiratory failure caused by impaired development of the diaphragm and intercostal muscles. In another model, the mice remained alive and their postnatal growth was reduced.

In conclusion, findings in humans and in animals show that IGF-1 deficiencies causes pronounced growth retardation in the presence of increased GH values.

The following is a summary of the results of the growth stimulating effects of the administration of exogenous IGF-1 to children and experimental data.

Growth promoting effects of IGF-1

The first demonstration that exogenous IGF-1 stimulates growth was the administration of purified hormone to hypophysectomised rats. After the biosynthesis of IGF-1 identical to the native hormone, trials of its use in humans were begun; first in adults and then in children. Our group was the first to introduce long term administration of biosynthetic IGF-1 to children with primary IGF-1 deficiency—primary GH insensitivity or LS. The finding that daily IGF-1 administration raises serum alkaline phosphatose, which is an indicator of osteoblastic activity, and serum procollagen, in addition to IGFBP-3, led to long term treatment. Treatment of patients with LS was also initiated in other parts of the world. The difference between us and the other groups was that we used a once daily dose, whereas the others administered IGF-1 twice daily. Table 1▶ compares the linear growth response of children with LS treated by four different groups. It can be seen that before treatment the mean growth velocity was 3–4.7 cm/year and that this increased after IGF-1 treatment to 8.2–9.1 cm/year, followed by a lower velocity of 5.5–6.4 cm/year in the next two years. (In GH treatment the highest growth velocity registered is also in the first year of treatment.) Figure 5▶ illustrates the growth response to IGF-1 in eight children during the first years of treatment. Ranke and colleagues reported that two of their patients had reached the third centile (Tanner), as did the patient of Krzisnik and Battelino; however, most patients did not reach a normal final height. The reasons may be late initiation of treatment, irregular IGF-1 administration, underdosage, etc. Ranke et al conclude that long term treatment of patients with LS promoted growth and, if treatment is started at an early age, there is a considerable potential for achieving height normalisation. Because no patient in our group was treated since early infancy to final height we cannot confirm this opinion.

Table 1

Linear growth response of children with Laron syndrome treated by means of insulin-like growth factor 1 (IGF-1)

At start Growth velocity (cm/year) Year of treatment
Authors Year Ref. N Age range (years) BA (years) Ht SDS (m) IGF-1 dose (μg/kg/day) 0 1st 2nd 3rd
(n = 26) (n = 18)
Ranke et al 1995 31 3.7–19 1.8–13.3 −6.5 40–120 b.i.d. 3.9 (1.8) 8.5 (2.1) 6.4 (2.2)
(n = 5) (n = 5) (n = 1)
Backeljauw et al 1996 5 2–11 0.3–6.8 −5.6 80–120 b.i.d. 4.0 9.3 6.2 6.2
(n = 9) (n = 6) (n = 5)
Klinger and Laron 1995 9 0.5–14 0.2–11 −5.6 150–200 i.d 4.7 (1.3) 8.2 (0.8) 6 (1.3) 4.8 (1.3)*
(n = 15) (n = 15) (n = 6)
Guevarra-Aguirre et al 1997 15 3.1–17 4.5–9.3 120 b.i.d. 3.4 (1.4) 8.8 (11) 6.4 (1.1) 5.7 (1.4)
(n = 8) (n = 8)
Guevarra-Aguire et al 8 80 b.i.d. 3.0 (1.8) 9.1 (2.2) 5.6 (2.1)

Growth velocity values are mean (SD).

*The younger children had a growth velocity of 5.5 and 6.5 cm/year.

BA, bone age; b.i.d., twice daily; CA, chronological age; i.d., once daily; Ht SDS, height standard deviation score.

When the growth response to GH treatment in infants with IGHD was compared with that of IGF-1 in infants with LS we found that the infants with IGHD responded faster and better than those with LS. However, the small number of patients and the differences in growth retardation between the two groups makes it difficult to reach a conclusion.

Both hormones stimulated linear growth, but GH seemed more effective than IGF-1. One cause may be the greater growth deficit of the infants with LS than those with IGHD, an insufficient dose of IGF-1, or that there is a need for some GH to provide an adequate stem cell population of prechondrocytes to enable full expression of the growth promoting action of IGF-1, as postulated by Green and colleagues and Ohlson et al. All the above findings based on a few clinical studies with small groups of patients and a few experimental studies remain at present controversial. The crucial question is whether there are any, and if so, whether there are sufficient IGF-1 receptors in the “progenitor cartilage zone” of the epiphyseal cartilage (fig 4▶) to respond to endocrine and exogenous IGF-1. Using the mandibular condyle of 2 day old ICR mice, Maor et al showed that these condyles, which resemble the epiphyseal plates of the long bones, contain IGF-1 and high affinity IGF-1 receptors also in the chondroprogenitor cell layers, which enables them to respond to IGF-1 in vitro.

Sims et al, using mice with GH receptor KO showed that IGF-1 administration stimulates the growth (width) of the tibial growth plate and that IGF-1 has a GH independent effect on the growth plate. These findings are similar to those found when treating hypophysectomised rats with IGF-1.

In conclusion, IGF-1 is an important growth hormone, mediating the anabolic and linear growth promoting effect of pituitary GH protein. It has a GH independent growth stimulating effect, which with respect to cartilage cells is possibly optimised by the synergistic action with GH.

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35. Laron Z, Pertzelan A, Karp M, et al. Administration of growth hormone to patients with familial dwarfism with high plasma immunoreactive growth hormone. Measurement of sulfation factor, metabolic and linear growth responses. J Clin Endocrinol Metab 1971;33:332–42. [PubMed] []
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38. Godowski PJ, Leung DW, Meacham LR, et al. Characterization of the human growth hormone receptor gene and demonstration of a partial gene deletion in 2 patients with Laron type dwarfism. Proc Natl Acad Sci U S A 1989;86:8083–7. [PMC free article] [PubMed] []
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41. Laron Z. Laron type dwarfism (hereditary somatomedin deficiency): a review. In: Frick P, Von Harnack GA, Kochsiek GA, et al, eds. Advances in internal medicine and pediatrics. Berlin-Heidelberg: Springer-Verlag, 1984:117–50. [PubMed]
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43. Brat O, Ziv I, Klinger B, et al. Muscle force and endurance in untreated and human growth hormone or insulin-like growth factor-I-treated patients with growth hormone deficiency or Laron syndrome. Horm Res 1997;47:45–8. [PubMed] []
44. Lurie R, Ben-Amitai D, Laron Z. Impaired hair growth and structural defects in patients with Laron syndrome (primary IGF-I deficiency) [abstract]. Horm Res 2001 [In press.]
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58. Klinger B, Jensen LT, Silbergeld A, et al. Insulin-like growth factor-I raises serum procollagen levels in children and adults with Laron syndrome. Clin Endocrinol 1996;45:423–9. [PubMed] []
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ℹ️ Basics: Cushing’s Syndrome vs Cushing’s Disease

MaryO Basic Info , , ,

What is Cushing’s syndrome?

Any condition that causes the adrenal gland to produce excessive cortisol results in the disorder Cushing’s syndrome. Cushing syndrome is characterized by facial and torso obesity, high blood pressure, stretch marks on the belly, weakness, osteoporosis, and facial hair growth in females.

Cushing’s syndrome has many possible causes including tumors within the adrenal gland, adrenal gland stimulating hormone (ACTH) produced from cancer such as lung cancer, and ACTH excessively produced from a pituitary tumors within the brain. ACTH is normally produced by the pituitary gland (located in the center of the brain) to stimulate the adrenal glands’ natural production of cortisol, especially in times of stress.

When a pituitary tumor secretes excessive ACTH, the disorder resulting from this specific form of Cushing’s syndrome is referred to as Cushing’s disease.

As an aside, it should be noted that doctors will sometimes describe certain patients with features identical to Cushing’s syndrome as having ‘Cushingoid’ features. Typically, these features are occurring as side effects of cortisone-related medications, such as prednisone and prednisolone.

🎬 Endoscopic Transsphenoidal Approach for Pituitary Tumor Resection

MaryO Uncategorized , , , , , , , , ,

Please be advised that this video contains graphic footage of surgery.

This video depicts an endoscopic transsphenoidal pituitary approach for a patient with a non-functioning macroadenoma. The surgery was performed by Dr. Garret Choby (Otolaryngology) and Dr. Jamie Van Gompel (Neurosurgery).

ℹ️ Cushing’s Basics: The Endocrine System

MaryO Basic Info , , , ,

The endocrine system is a complex network of glands and organs. It uses hormones to control and coordinate your body’s metabolism, energy level, reproduction, growth and development, and response to injury, stress, and mood. The following are integral parts of the endocrine system:

 

  • Hypothalamus. The hypothalamus is located at the base of the brain, near the optic chiasm where the optic nerves behind each eye cross and meet. The hypothalamus secretes hormones that stimulate or suppress the release of hormones in the pituitary gland, in addition to controlling water balance, sleep, temperature, appetite, and blood pressure.
  • Pineal body. The pineal body is located below the corpus callosum, in the middle of the brain. It produces the hormone melatonin, which helps the body know when it’s time to sleep.
  •  Pituitary . The pituitary gland is located below the brain. Usually no larger than a pea, the gland controls many functions of the other endocrine glands.
  • Thyroid and parathyroid. The thyroid gland and parathyroid glands are located in front of the neck, below the larynx (voice box). The thyroid plays an important role in the body’s metabolism. The parathyroid glands play an important role in the regulation of the body’s calcium balance.
  • Thymus. The thymus is located in the upper part of the chest and produces white blood cells that fight infections and destroy abnormal cells.
  •  Adrenal gland . An adrenal gland is located on top of each kidney. Like many glands, the adrenal glands work hand-in-hand with the hypothalamus and pituitary gland. The adrenal glands make and release corticosteroid hormones and epinephrine that maintain blood pressure and regulate metabolism.
  •  Pancreas . The pancreas is located across the back of the abdomen, behind the stomach. The pancreas plays a role in digestion, as well as hormone production. Hormones produced by the pancreas include insulin and glucagon, which regulate levels of blood sugar.
  • Ovary. A woman’s ovaries are located on both sides of the uterus, below the opening of the fallopian tubes (tubes that extend from the uterus to the ovaries). In addition to containing the egg cells necessary for reproduction, the ovaries also produce estrogen and progesterone.
  • Testis. A man’s testes are located in a pouch that hangs suspended outside the male body. The testes produce testosterone and sperm.

📅 Save the Date: 2025 Neuro-Endocrine Pituitary Conference: For Physicians, Nurses & Patients

MaryO Interviews, Meetings and Conferences , , , ,

A unique collaboration from Pacific Neuroscience Institute

8th California Pituitary Conference for Providers | 16th Annual Neuroscience Nursing Symposium | Educational Seminar for Patients

November 1 – 2, 2025, 8 AM – 5 PM

LA Puglia, 1621 Wilshire Blvd, Santa Monica, CA 90403

Course Directors

Noa Tal, MD

Amy Eisenberg MSN, ARNP, CNRN

This two-day course has something for everyone.

Day 1 focuses on in-depth information for nurses and patients in two separate curated sessions.

Day 2 geared toward physicians and nurses provides an extensive immersion in advanced topics led by highly experienced and recognized experts in their fields.

📽 Video: How an Emergency Injection works!

MaryO Uncategorized , , , , , , , , ,

What should you do if an Addison crisis threatens? How do you prepare an emergency injection and how do you administer it?

If you have a gastrointestinal infection, accompanied by diarrhea and vomiting, there is a big risk of an Addison crisis.

Always discuss with your specialist what you have done and what else needs to be done. Explain to your family, colleagues and friends what illness you have, and what they should do if necessary.

Show them the animated clip below.

⁉️ Would *YOU* Do This?

MaryO What do you think? , , , , , , ,

I remember someone on the House TV series trying a stunt like this on the episode titled Deception.

At a betting parlor where House happens to be, a woman collapses and House makes sure she gets to the hospital. He thinks she has Cushing’s syndrome while Cameron starts to think she has Münchausen syndrome, a syndrome at which the patient creates the symptoms of a disease, guaranteeing them attention and sympathy.

Rare Case of Woman Manipulating Saliva Tests to Support Cushing’s Diagnosis

Late-night measures of cortisol levels in saliva may not be all that helpful in diagnosing Cushing’s syndrome, a group of physicians discovered upon learning that a difficult to diagnose patient had manipulated the samples.

Although this behavior is extremely rare, the research team from the University of Calgary in Canada, argued that — when a diagnosis becomes difficult — it may be advisable to confirm suspicions using another and more reliable method that can distinguish natural from synthetic glucocorticoids.

The study, “Factitious ACTH- dependent, apparent hypercortisolism: the problem with late night salivary cortisol measurements collected at home,” was published in the journal Clinical Endocrinology.

The case report described a woman who was admitted to a specialist clinic after two endocrinologists had failed to diagnose what they suspected was cyclic Cushing’s syndrome.

The woman had complained of fatigue and weight gain over the past four years despite weight loss banding surgery, and declined taking steroid medications. The examination did not reveal particular Cushing’s symptoms.

Physicians started an investigation, including overnight dexamethasone suppression tests and late-night salivary cortisol tests, which indicate increased levels of cortisol likely caused by abnormal functioning of the ACTH hormone.

Imaging did not show any suspected lesions in the pituitary and adrenal gland, and all further examinations did not reveal any disease changes that might have contributed to the increased cortisol.

The woman was put on a dopamine agonist. This treatment triggered a loss of eight kilograms (almost 18 lbs) over six months, and the woman said she was satisfied with it. But two late-night cortisol measurement showed continuing high cortisol levels.

When the clinic started using a new type of analysis to measure cortisol, however, findings changed. The new test, which was more sensitive, indicated massively higher doses of cortisol in re-analyzed saliva samples compared to the older results.

The new test could detect synthetic glucosteroids, but could not indicate if synthetic steroids were responsible for the higher levels seen in the retest. So the team used a method called liquid chromatography-tandem mass spectrometry. This technique can identify specific molecules, and revealed that the women had manipulated the samples using prednisone.

The woman’s physician also paid a surprise visit to collect a new saliva sample, which turned out to have normal cortisol levels.

The woman neither denied or confirmed manipulating the samples. And the team was contacted two months later by her new physician, requesting confirmation of her Cushing’s syndrome and details on her case.

The researchers believed the woman most likely has what is known as Munchausen’s syndrome, a mental illness that leads patients to feign physical disease. A 1995 report by the National Institutes of Health showed that 0.7 percent of all people investigated for too high cortisol had this syndrome.

Despite the rarity of this case, the team argued that chemical analysis is a valuable tool for both determining sample manipulation in difficult Cushing’s syndrome cases, or a different potential problem.

They also cautioned against putting too much trust in very elevated late-night cortisol, particularly when the symptoms do not match the cortisol increase.

From https://cushingsdiseasenews.com/2017/10/05/rare-case-of-woman-manipulating-late-night-saliva-cortisol-tests-to-get-cushings-diagnosis/

❓Has Cushing’s Affected your Job or Quality of Life?

MaryO What do you think? , , , , , ,

I would love to take one of the surveys mentioned in this news article.  My Cushing’s went into “remission” just over 31 years ago but I still feel the effects of having had it.

Pre-Cushing’s I had no problem working a full day, having a piano studio overflowing with students, going out at night, cleaning the house, being a normal mom.

I could do as I chose – if I wanted to go somewhere, or do something, I just did.

Now, I work part-time and my studio is much smaller.  Everything I do is to accommodate my nap schedule.  I have to plan everything carefully so I can take my meds on time and be ready to sleep.

Even going to regular doctors is harder, explaining why I take cortisone and growth hormone, why I can’t take whatever meds they want to prescribe.

Discussing with a sports medicine doctor why I should (or shouldn’t) have a cortisone shot in my knee.  (I went for it September 12!  Now I’ll have to explain to my endo.)

Unfortunately, I also haven’t lost all my Cushing’s weight (probably at least partly my own fault LOL) and I still have to shave my chin every day.

I honestly believed that my kidney cancer was due to my taking growth hormone, which I take because of my pituitary tumor.  Now, since I’m back on it, I’m not entirely sure – but who knows what else might be growing?  Or maybe the different brand is better for me.  Who can say?

What about you?  How has your life changed due to Cushing’s?