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.
Post 1) I was officially diagnosed with Cushing’s yesterday. I have a CT scan to check on my adrenal tumor and a meeting with my surgeon tomorrow. Hopefully they will schedule surgery for Monday or Tuesday. I have suffered over a year with this, been in congestive heart failure, and believe this cortisol caused my son to be stillborn in March. It’s been the year from hell. Please pray that all goes well tomorrow and that I will be cured of this once and for all!!
Post 2) Surgery set for the 23rd!!!!! He is planning a right adrenaltectomy. I am so darn excited…
Post 3) I’m almost two weeks out of adrenal surgery. He removed the tumor & my gland. This has been the hardest and most painful two weeks of my life. I am already noticing little changes in my body. My skin is getting texture, my hair is not as brittle, my swelling goes down each day, and my nails are white instead of yellow and are stronger. I am getting hair back on my arms, legs, & feet too. I can’t wait to continue to get well. I am ready to be able to get out and about. I am pretty much housebound now because of the pain of the withdrawal from the cortisol. I stay on my painkillers and rest in my recliner. Hubby bought it for me because I can’t sleep in the bed comfortably. He’s the best. He’s been sleeping on our air mattress in the living room with me for almost 2 weeks now. He is always there to help me get out of the recliner when I need to. He is amazing. Just wanted to update you all. Getting better everyday.
Post 4) I am on 40mg Hydrocortisone daily right now. I will have my first wean close to Christmas. I have an appt. on the 21st with my endo. She is fantastic and saved my life from this stuff. I am so blessed. Today is a rough day. I did have 2 good days in a row which was a huge blessing. Thanks for thinking of me!
Post 5) Well, I just survived month 1 of recovery. It was HORRIBLE. I have never had so much pain in my life. I am still on 40 mg and my endo. wants me to wean 10 mg starting on the 27th. We’ll see how it goes. I have so much pain, shaking, chills, no sleep NOW. I can’t imagine how its going to be on a lower dose. My cortisol level was SO HIGH (2107) before surgery. I knew this withdrawal was going to be terrible. SHe had never seen a level as high as mine before. The lab actually tested my urine twice because they didn’t believe it the first time. I am doing a lot of resting right now. I am very nervous about my mother leaving on New Year’s Day. I don’t know how I am going to handle my 3 year old on my own. I hurt so badly and my vision isn’t the greatest yet. Thanks for thinking of me and writing me back.
Post 6) We have another call into my endo about my suffering. I have done nothing but shake uncontrollably all day so far. I hurt so badly. I am up every hour at night writhing in pain. I refuse to suffer like this anymore. I want some relief. Thank you so much for all of the advice. It means the world to me. Great news is that I am off my BP meds as of today!! Cardiologist’s office said I could quit them. I am thrilled. Now to get this pain under control.
Post 7) Endo said we can do whatever I can tolerate. I am now doing 20/20/10 instead of 20/10/10. I am still in pain, but it’s a little more tolerable. She said if I am just miserable and can’t take the pain, then I can do a bedtime dose. I am going to try melatonin to help me sleep per her suggestion. She wants to see how I do on this new dose and start a slow wean in a few weeks.
Post 8) Things have been getting better by the week. New years day was my best physical and mental day so far. I can actually feel my old self returning! !! Today I have lots of bone/muscle pain. Its better than a few weeks ago by far. Yesterday I was able to enjoy my son and play with him for the first time in a long time. I could even dance a little with him. He was so happy. I am down to 20/17.5/10& am handling it well. The pain is tolerable. My hump is almost gone, my stomach is mushy and shrinking, skin is peeling and improving, hair is growing in normally. I will be six weeks out this Wed.
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.”
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),1 but also by other hypothalamic peptides called GH secretagogues,2 which seem to act in synergism with GHRH3 by inhibiting somatostatin.4 One of these has been cloned and named Ghrelin.5 The interplay between GHRH and somatostatin induces a pulsatile GH secretion,6 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.7
IGF-1 and IGF-2 were identified in 1957 by Salmon and Daughaday8 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).9 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.10 In 1976, Rinderknecht and Humbel11 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.12
CHEMICAL STRUCTURE
The IGFs are members of a family of insulin related peptides that include relaxin and several peptides isolated from lower invertebrates.13 IGF-1 is a small peptide consisting of 70 amino acids with a molecular weight of 7649 Da.14 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 12q23–23.15,16 The human IGF-1 gene consists of six exons, including two leader exons, and has two promoters.17
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.18 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.19 IGFBP-1 is regulated by insulin and IGF-120; IGFBP-3 is regulated mainly by GH but also to some degree by IGF-1.21
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 15q25–26.22 The gene contains 21 exons (fig 2▶) and its organisation resembles that of the structurally related insulin receptor (fig 3▶).23 The type 1 IGF receptor gene is expressed by almost all tissues and cell types during embryogenesis.24 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.25 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.26
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.27 IGF-1 is also secreted by other tissues,28 including cartilagenous cells, and acts locally as a paracrine hormone (fig 4▶).29 It is also assumed that IGF-1 can act in an autocrine manner as an oncogene.30 The role of IGF-1 in the metabolism of many tissues including growth has been reviewed recently.31,32
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 1968,33,34 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-1.35
This syndrome of GH resistance (insensitivity) was named by Elders et al as Laron dwarfism,36 a name subsequently changed to Laron syndrome (LS).37 Molecular studies revealed that the causes of GH resistance are deletions38 or mutations39 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.40 This fact is enforced by the findings that already at birth, and throughout childhood, skeletal maturation is retarded, as is organ growth.41 These growth abnormalities include a small brain (as expressed by head circumference),41 a small heart (cardiomicria),42 and acromicria (small chin, resulting from underdevelopment of the facial bones, small hands, and small feet).33,34 IGF-1 deficiency also causes underdevelopment and weakness of the muscular system,43 and impairs and weakens hair44 and nail growth. These findings are identical to those described in IGHD.45 IGF-1 deficiency throughout childhood causes dwarfism (final height if untreated, 100–135 cm in female and 110–142 cm in male patients),40,41 with an abnormally high upper to lower body ratio.41 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.46
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.47–49
Knockout of the IGF-1 gene or the IGF-1 receptor gene reduces the size of mice by 40–45%.49 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.49 In another model, the mice remained alive and their postnatal growth was reduced.50
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.
The first demonstration that exogenous IGF-1 stimulates growth was the administration of purified hormone to hypophysectomised rats.51,52 After the biosynthesis of IGF-1 identical to the native hormone,53 trials of its use in humans were begun; first in adults54 and then in children.55,56 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.57 The finding that daily IGF-1 administration raises serum alkaline phosphatose, which is an indicator of osteoblastic activity, and serum procollagen,57,58 in addition to IGFBP-3,21 led to long term treatment. Treatment of patients with LS was also initiated in other parts of the world.59–62 The difference between us and the other groups was that we used a once daily dose, whereas the others administered IGF-1 twice daily.60 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.65 Ranke and colleagues60 reported that two of their patients had reached the third centile (Tanner), as did the patient of Krzisnik and Battelino66; 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.60 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)
*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.67 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 colleagues68 and Ohlson et al.69 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.70
Sims et al,71 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-1.51,52
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.
1. Tannenbaum GS, Ling N. The interrelationship of growth hormone (GH)-releasing factor and somatostatin in generation of the ultradian rhythm of GH secretion. Endocrinology 1984;115:1952–7. [PubMed] [Google Scholar]
2. Laron Z. Growth hormone secretagogues: clinical experience and therapeutic potential. Drugs 1995;50:595–601. [PubMed] [Google Scholar]
3. Ghigo E, Boghen M, Casanueva FF, et al., eds. Growth hormone secretagogues. Basic findings and clinical implications. Amsterdam: Elsevier, 1994.
4. Jaffe CA, Ho PJ, Demott-Friberg R, et al. Effects of a prolonged growth hormone (GH)-releasing peptide infusion on pulsatile GH secretion in normal men. J Clin Endocrinol Metab 1993;77:1641–7. [PubMed] [Google Scholar]
5. Kojima M, Hosada H, Date Y, et al. Ghrelin is a growth-hormone-releasing acylated peptide from stomach. Nature 1999;402:656–60. [PubMed] [Google Scholar]
6. Devesa J, Lima L, Tresquerres AF. Neuroendocrine control of growth hormone secretion in humans. Trends Endocrinol Metab 1992;3:175–83. [PubMed] [Google Scholar]
7. Laron Z. The somatostatin-GHRH-GH-IGF-I axis. In: Merimee T, Laron Z, eds. Growth hormone, IGF-I and growth: new views of old concepts. Modern endocrinology and diabetes, Vol. 4. London-Tel Aviv: Freund Publishing House Ltd, 1996:5–10.
8. Salmon WD, Jr, Daughaday W. A hormonally controlled serum factor which stimulates sulfate incorporation by cartilage in vitro. J Lab Clin Med 1957;49:825–36. [PubMed] [Google Scholar]
9. Froesch ER, Burgi H, Ramseier EB, et al. Antibody-suppressible and nonsuppressible insulin-like activities in human serum and their physiologic significance. An insulin assay with adipose tissue of increased precision and specificity. J Clin Invest 1963;42:1816–34. [PMC free article] [PubMed] [Google Scholar]
10. Daughaday WH, Hall K, Raben MS, et al. Somatomedin: a proposed designation for the sulfation factor. Nature 1972;235:107. [PubMed] [Google Scholar]
11. Rinderknecht E, Humbel RE. Polypeptides with non-suppressible insulin-like and cell-growth promoting activities in human serum: isolation, chemical characterization, and some biological properties of forms I and II. Proc Natl Acad Sci U S A 1976;73:2365–9. [PMC free article] [PubMed] [Google Scholar]
12. Laron Z. Somatomedin-1 (recombinant insulin-like growth factor-I). Clinical pharmacology and potential treatment of endocrine and metabolic disorders. Biodrugs 1999;11:55–70. [PubMed] [Google Scholar]
14. Rinderknecht E, Humbel RE. The amino acid sequence of human insulin like growth factor I and its structural homology, with proinsulin. J Biol Chem 1978;253:2769–76. [PubMed] [Google Scholar]
15. Brissenden JE, Ullrich A, Francke U. Human chromosomal mapping of genes for insulin-like growth factors I and II and epidermal growth factor. Nature 1984;310:781–4. [PubMed] [Google Scholar]
16. Mullis PE, Patel MS, Brickell PM, et al. Growth characteristics and response to growth hormone therapy in patients with hypochondroplasia: genetic linkage of the insulin-like growth factor I gene at chromosome 12q23 to the disease in a subgroup of these patients. Clin Endocrinol 1991;34:265–74. [PubMed] [Google Scholar]
17. Rotwein P. Structure, evolution, expression and regulation of insulin-like growth factors I and II. Growth Factors 1991;5:3–18. [PubMed] [Google Scholar]
18. Hwa V, Oh Y, Rosenfeld RG. The insulin-like growth factor binding protein (IGFBP) superfamily. Endocr Rev 1999;20:761–87 [PubMed] [Google Scholar]
19. Lewitt MS, Saunders H, Phuyal JL, et al. Complex formation by human insulin-like growth factor-binding protein-3 and human acid-labile subunit in growth hormone-deficient rats. Endocrinology 1994;134:2402–9. [PubMed] [Google Scholar]
20. Laron Z, Suikkairi AM, Klinger B, et al. Growth hormone and insulin-like growth factor regulate insulin-like growth factor-binding protein-1 in Laron type dwarfism, growth hormone deficiency and constitutional short stature. Acta Endocrinol 1992;127:351–8. [PubMed] [Google Scholar]
21. Kanety H, Karasik A, Klinger B, et al. Long-term treatment of Laron type dwarfs with insulin-like growth factor I increases serum insulin-like growth factor-binding protein 3 in the absence of growth hormone activity. Acta Endocrinol 1993;128:144–9. [PubMed] [Google Scholar]
22. Werner H. Molecular biology of the type I IGF receptor. In: Rosenfeld RG, Roberts CT, Jr, eds. The IGF system—molecular biology, physiology and clinical applications. Totowa, NJ: Humana Press, 1999:63–88.
23. Seino S, Seino M, Nishi S, et al. Structure of the human insulin receptor gene and characterization of its promoter. Proc Natl Acad Sci U S A 1989;86:114–18. [PMC free article] [PubMed] [Google Scholar]
24. Bondy CA, Werner H, Roberts CT, Jr, et al. Cellular pattern of insulin-like growth factor I (IGF-I) and type I IGF receptor gene expression in early organogenesis: comparison with IGF-II gene expression. Mol Endocrinol 1990;4:1386–98. [PubMed] [Google Scholar]
25. Kato H, Faria TN, Stannard B, et al. Essential role of tyrosine residues 1131, 1135, and 1136 of the insulin-like growth factor-I (IGF-I) receptor in IGF-I action. Mol Endocrinol 1994;8:40–50. [PubMed] [Google Scholar]
26. LeRoith D, Werner H, Beitner-Johnson D, et al. Molecular and cellular aspects of the insulin-like growth factor I receptor. Endocr Rev 1995;16:143–63. [PubMed] [Google Scholar]
27. Merimee T, Laron Z, eds. Growth hormone, IGF-I and growth: new views of old concepts. Modern endocrinology and diabetes, Vol. 4. London-Tel Aviv: Freund Publishing House Ltd, 1996.
28. D’Ercole AJ, Applewhite GT, Underwood LE. Evidence that somatomedin is synthesized by multiple tissues in the fetus. Dev Biol 1980;75:315–28 [PubMed] [Google Scholar]
29. Nilsson A, Isgaard J, Lindhahl A, et al. Regulation by growth hormone of number of chondrocytes containing IGF-I in rat growth plate. Science 1986;233:571–4. [PubMed] [Google Scholar]
30. Baserga R. The IGF-I receptor in cancer research. Exp Cell Res 1999;253:1–6. [PubMed] [Google Scholar]
31. Rosenfeld RG, Roberts CT, Jr, eds. The IGF system—molecular biology, physiology and clinical applications. Totowa, NY: Humana Press, 1999.
32. Zapf J, Froesch ER. Insulin-like growth factor I actions on somatic growth. In: Kostyo J, ed. Handbook of physiology, Vol. V, Section 7. Philadelphia: American Physiological Society, 1999:663–99.
33. Laron Z, Pertzelan A, Mannheimer S. Genetic pituitary dwarfism with high serum concentration of growth hormone. A new inborn error of metabolism? Isr J Med Sci 1966;2:153–5. [PubMed] [Google Scholar]
34. Laron Z, Pertzelan A, Karp M. Pituitary dwarfism with high serum levels of growth hormone. Isr J Med Sci 1968;4:883–94. [PubMed] [Google Scholar]
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] [Google Scholar]
36. Elders MJ, Garland JT, Daughaday WH, et al. Laron’s dwarfism: studies on the nature of the defect. J Pediatr 1973;83:253–63. [PubMed] [Google Scholar]
37. Laron Z, Parks JS, eds. Lessons from Laron syndrome (LS) 1966–1992. A model of GH and IGF-I action and interaction. Pediatric and Adolescent Endocrinology 1993;24:1–367. [Google Scholar]
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] [Google Scholar]
39. Amselem S, Duquesnoy P, Attree O, et al. Laron dwarfism and mutations of the growth hormone-receptor gene. N Engl J Med 1989;321:989–95. [PubMed] [Google Scholar]
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]
42. Feinberg MS, Scheinowitz M, Laron Z. Echocardiographic dimensions and function in adults with primary growth hormone resistance (Laron syndrome). Am J Cardiol 2000;85:209–13. [PubMed] [Google Scholar]
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] [Google Scholar]
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.]
45. Gluckman PD, Gunn AJ, Wray A, et al. Congenital idiopathic growth hormone deficiency associated with prenatal and early postnatal growth failure. J Pediatr 1992;121:920–3. [PubMed] [Google Scholar]
46. Woods KA, Camacho-Hubner C, Savage MO, et al. Intrauterine growth retardation and postnatal growth failure associated with deletion of the insulin-like growth factor I gene. N Engl J Med 1996;335:1363–7. [PubMed] [Google Scholar]
47. Zhou Y, Xu BC, Maheshwari HG, et al. A mammalian model for Laron syndrome produced by targeted disruption of the mouse growth hormone receptor/binding protein gene (the Laron mouse). Proc Natl Acad Sci U S A 1997;94:13215–20. [PMC free article] [PubMed] [Google Scholar]
48. Sjogren K, Bohlooly YM, Olsson B, et al. Disproportional skeletal growth and markedly decreased bone mineral content in growth hormone receptor –/– mice. Biochem Biophys Res Commun 2000;267:603–8. [PubMed] [Google Scholar]
49. Accili D, Nakae J, Kim JJ, et al. Targeted gene mutations define the roles of insulin and IGF-I receptors in mouse embryonic development. J Pediatr Endocrinol Metab 1999;12:475–85. [PubMed] [Google Scholar]
50. Holzenberger M, Leneuve P, Hamard G, et al. A targeted partial invalidation of the insulin-like growth factor-I receptor gene in mice causes a postnatal growth deficit. Endocrinology 2000;141:2557–66. [PubMed] [Google Scholar]
51. Schoenle E, Zapf J, Humbel RE, et al. Insulin-like growth factor I stimulates growth in hypophysectomized rats. Nature 1982;296:252–3. [PubMed] [Google Scholar]
52. Guler H-P, Zapf J, Scheiwiller E, et al. Recombinant human insulin-like growth factor I stimulates growth and has distinct effects on organ size in hypophysectomized rats. Proc Natl Acad Sci U S A 1988;85:4889–93. [PMC free article] [PubMed] [Google Scholar]
53. Niwa M, Sato Y, Saito Y, et al. Chemical synthesis, cloning and expression of genes for human somatomedin C (insulin like growth factor I) and 59Val somatomedin C. Ann N Y Acad Sci 1986;469:31–52. [PubMed] [Google Scholar]
54. Guler HP, Zapf J, Froesch ER. Short term metabolic effects of recombinant human insulin like growth factor in healthy adults. N Engl J Med 1987;317:137–40. [PubMed] [Google Scholar]
55. Laron Z, Klinger B, Silbergeld A, et al. Intravenous administration of recombinant IGF-I lowers serum GHRH and TSH. Acta Endocrinol 1990;123:378–82. [PubMed] [Google Scholar]
56. Klinger B, Garty M, Silbergeld A, et al. Elimination characteristics of intravenously administered rIGF-I in Laron type dwarfs (LTD). Dev Pharmacol Ther 1990;15:196–9. [PubMed] [Google Scholar]
57. Laron Z, Klinger B, Jensen LT, et al. Biochemical and hormonal changes induced by one week of administration of rIGF-I to patients with Laron type dwarfism. Clin Endocrinol 1991;35:145–50. [PubMed] [Google Scholar]
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] [Google Scholar]
59. Underwood LE, Backeljauw P. IGFs: function and clinical importance of therapy with recombinant human insulin-like growth factor I in children with insensitivity to growth hormone and in catabolic conditions. J Intern Med 1993;234:571–7. [PubMed] [Google Scholar]
60. Ranke MB, Savage MO, Chatelain PG, et al. Long-term treatment of growth hormone insensitivity syndrome with IGF-I. Horm Res 1999;51:128–34. [PubMed] [Google Scholar]
61. Ranke MB, Savage MO, Chatelain PG, et al. Insulin-like growth factor (IGF-I) improves height in growth hormone insensitivity: two years results. Horm Res 1995;44:253–64. [PubMed] [Google Scholar]
62. Backeljauw PF, Underwood LE, The GHIS Collaborative Group. Prolonged treatment with recombinant insulin-like growth factor I in children with growth hormone insensitivity syndrome—a clinical research center study. J Clin Endocrinol Metab 1996;81:3312–17. [PubMed] [Google Scholar]
63. Klinger B, Laron Z. Three year IGF-I treatment of children with Laron syndrome. J Pediatr Endocrinol Metab 1995;8:149–58. [PubMed] [Google Scholar]
64. Guevara-Aguirre J, Rosenbloom AL, Vasconez O, et al. Two year treatment of growth hormone (GH) receptor deficiency with recombinant insulin-like growth factor-I in 22 children: comparison of two dosage levels and to GH treated GH deficiency. J Clin Endocrinol Metab 1997;82:629–33. [PubMed] [Google Scholar]
66. Krzisnik C, Battelino T. Five year treatment with IGF-I of a patient with Laron syndrome in Slovenia (a follow-up report). J Pediatr Endocrinol Metab 1997;10:443–7. [PubMed] [Google Scholar]
67. Laron Z, Klinger B. Comparison of the growth-promoting effects of insulin-like growth factor I and growth hormone in the early years of life. Acta Paediatr 2000;89:38–41. [PubMed] [Google Scholar]
68. Green H, Morikawa M, Nixon T. A dual effector theory of growth hormone action. Differentiation 1985;29:195–8. [PubMed] [Google Scholar]
69. Ohlson C, Bengtsson BA, Isaksson OG, et al. Growth hormone and bone. Endocr Rev 1998;19:55–79. [PubMed] [Google Scholar]
70. Maor G, Laron Z, Eshet R, et al. The early postnatal development of the murine mandibular condyle is regulated by endogenous insulin-like growth factor-I. J Endocrinol 1993;137:21–6. [PubMed] [Google Scholar]
71. Sims NA, Clement-Lacroix P, Da Ponte F, et al. Bone homeostatis in growth hormone receptor-null mice is restored by IGF-I but independent of Stat5. J Clin Invest 2001;106:1095–103. [PMC free article] [PubMed] [Google Scholar]
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.
A TSH test is done to find out if your thyroid gland is working the way it should. It can tell you if it’s overactive (hyperthyroidism) or underactive (hypothyroidism). The test can also detect a thyroid disorder before you have any symptoms. If untreated, a thyroid disorder can cause health problems.
TSH stands for “thyroid stimulating hormone” and the test measures how much of this hormone is in your blood. TSH is produced by the pituitary gland in your brain. This gland tells your thyroid to make and release the thyroid hormones into your blood.
The Test
The TSH test involves simply drawing some blood from your body. The blood will then be analyzed in a lab. This test can be performed at any time during the day. No preparation is needed (such as overnight fasting). You shouldn’t feel any pain beyond a small prick from the needle in your arm. You may have some slight bruising.
In general, there is no need to stop taking your medicine(s) before having your TSH level checked. However, it is important to let the doctor know what medications you are taking as some drugs can affect thyroid function. For example, thyroid function must be monitored if you are taking lithium. While taking lithium, there is a high chance that your thyroid might stop functioning correctly. It’s recommended that you have a TSH level test before starting this medicine. If your levels are normal, then you can have your levels checked every 6 to 12 months, as recommended by your doctor. If your thyroid function becomes abnormal, you should be treated.
High Levels of TSH
TSH levels typically fall between 0.4 and 4.0 milliunits per liter (mU/L), according to the American Thyroid Association. Ranges between laboratories will vary with the upper limit generally being between 4 to 5. If your level is higher than this, chances are you have an underactive thyroid.
In general, T3 and T4 levels increase in pregnancy and TSH levels decrease.
Low Levels of TSH
It’s also possible that the test reading comes back showing lower than normal levels of TSH and an overactive thyroid. This could be caused by:
Graves’ disease (your body’s immune system attacks the thyroid)
Too much iodine in your body
Too much thyroid hormone medication
Too much of a natural supplement that contains the thyroid hormone
If you’re on medications like steroids, dopamine, or opioid painkillers (like morphine), you could get a lower-than-normal reading. Taking biotin (B vitamin supplements) also can falsely give lower TSH levels.
The TSH test usually isn’t the only one used to diagnose thyroid disorders. Other tests, like the free T3, the free T4, the reverse T3, and the anti-TPO antibody, are often used too when determining whether you need thyroid treatment or not.
Treatment
Treatment for an underactive thyroid usually involves taking a synthetic thyroid hormone by pill daily. This medication will get your hormone levels back to normal, and you may begin to feel less tired and lose weight.
To make sure you’re getting the right dosage of medication, your doctor will check your TSH levels after 2 or 3 months. Once they are sure you are on the correct dosage, they will continue to check your TSH level each year to see whether it is normal.
If your thyroid is overactive, there are several options:
Radioactive iodine to slow down your thyroid
Anti-thyroid medications to prevent it from overproducing hormones
Beta blockers to reduce a rapid heart rate caused by high thyroid levels
Surgery to remove the thyroid (this is less common)
Your doctor may also regularly check your TSH levels if you have an overactive thyroid.
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.
As a person with secondary adrenal insufficiency, I find often find myself in a situation when I need to stress dose and balance the electrolytes. Many Cushies I know eat salt for this purpose but I don’t like salt. If I’m eating pretzels or something else with removeable salt – i take it off.
I don’t know if I found it by myself on amazon or someone recommended it but I always have a product called – TaDa! – SaltSticks nearby.
Writing this post today, I actually looked at the directions and found that I’m supposed to take 2 at a time. Oops! One does help somewhat. I’m sure that 2 will be even better.
To keep these and my hydrocortisone nearby, in addition to the actual bottles, I got some waterproof pill containers and keep them on my keychain. The wider ones hold 2 of the SaltSticks exactly.
The narrower ones have hydrocortisone and Tylenol. The hydrocortisone is in the red pill container.
All 3 are on one ring which goes onto my larger carabiner clip so that they can be easily moved if necessary.
In my backpack, I have an adrenal insufficiency emergency kit of sorts that I got off ebay. This also includes a bee sting kit. If you want to know why, check out this post. there is also information about my doctor, more hydrocortisone, benadryl, tylenol.
Both the keyring and the emergency kit have MedicAlert tags which include my member number so medics can find out just what I need, my DH number and my doctor’s number.
This info is also on my MedicAlert bracelet. I bought this one years ago to honor Natalie’s memory – this is the same style she wore.
Advice from a Volunteer Firefighter with Adrenal Insufficiency
My name is Jeannie, and I have been diagnosed with Secondary AI since March of 2015. To make a long story short, I was diagnosed with a pituitary adenoma in Feb of 2015. It was apron 8mm x 10mm at the time wit was found. On April 25th, 2015 I was getting ready for work in the early morning hours.. I passed out in my bathroom and was immediately rushed to the hospital by my husband. They did a secondary MRI and found that the tumor had tripled in size to 23mm x almost 41mm. My Cortisol was also so low it was undetectable by the lab. I was taken by ambulance to Emory University hospital in Atlanta where the Neurosurgeon I had been in consult with was. I arrived there on Sunday and was in Surgery Wednesday Morning. The surgery took 9 hours and recovery was close to 6.
Prior to this all taking place I was a volunteer firefighter, and had worked EMS for almost 16 years. I have been in nearly every situation possible. I see so many people that have our condition asking about Medic Alert bracelets, What kind they should have, what it should say on it, etc. So I have put together a short list to help out a little bit. This is coming from both someone who has this extremely rare disease, and also from the Emergency Medical Side of me. Knowing what We as medics look for in the field, How quickly things move, what we ask or need to know, etc.
Please know that this IS NOT Professional Medical advice, But this is advice coming from someone who can shed some light on how to potentially save your life if you should ever be alone, or without anyone who knows your condition and you fall unconscious or are unable to the the responders what your condition is.
First off if you are looking for a medic alert bracelet or wondering if you should get one.
**The answer is yes, If you have been diagnosed ANY TYPE of adrenal insufficient or are on replacement medication.. YES. you need one.**
Here are some of those reasons and some pointers on what they should look like / what they should say.
#1– If you are found unconscious, and there are not bystanders around to tell emergency crews what is wrong with you, You will go longer without your steroids. If we see on your bracelet that you are steroid dependent, it dissolves the ENTIRE guessing game of why you’re unconscious.
#2– It should have on there your emergency contact and a GOOD telephone number. That way if nothing else. We can call them. NOT EVERY EMS AGENCY HAS ACCESS TO THE “CLOUD” BASED SYSTEMS THAT STORE YOUR INFO. Please be sure that if your emergency contacts number changes.. You change it on your bracelet. There is nothing worse than wasted time calling a number that doesn’t belong to the person we NEED to talk to.
#3– DO NOT MAKE IT “PRETTY” OR “NOT SO OBVIOUS”. I can not stress this enough. Ladies I know that you want the cute ones that look like normal bracelets, and have pretty charms, etc on them… THE ENTIRE point of a medical alert bracelet is that someone needs to see it and know that they should look at it. If it looks like a regular bracelet or regular necklace and it isn’t obvious within the first 3 seconds once we get to you and look in the obvious places (neck/wrist). it will NOT get seen. I promise you, we are too busy trying to play the guessing game of why you are not responding, than to take a look at every single piece of regular jewelry and see if it might have a really small inscribing of what is wrong with you. Once again. Make it noticeable. We will see that we need to look at it. Once we do. The guessing game is more than likely OVER. and we can begin to treat you appropriately.
#4– Most EMT’s and Paramedics Don’t Understand or know about Addisons or the treatment involved. If nothing else, carry a letter from your doctor explaining what is wrong with you, etc. It is very rare, and NOT covered in most Paramedic courses. So please, for those of you that put “ADRENAL INSUFFICIENT” on your bracelet and NOT “STEROID DEPENDENT” please keep in mind that you may end up with the Paramedic that just graduated, is nervous, and will mistake adrenal insufficiency for Adrenaline insufficiency.. and try to give you epinephrine. Please understand that I have seen this almost happen. It is something that is easily misunderstood in the heat of the moment.
#5– If you have an emergency injection that you carry with you all the time, on your person, or somewhere close. PUT ON THERE THAT YOU HAVE IT! MOST ems agencies have standing protocol that they can assist with emergency medications (Don’t jump in here if you are one of those states that doesn’t allow it.. I said most) That way if we find you down, and look at your bracelet, AND see that you have emergency meds with you… guess what now, not only is the guessing game over, You’re ALSO getting the RIGHT EMERGENCY MEDS, instead of us having to either give you what we carry, or you having to wait until you get to the ER and the ER doc has to go through your file and figure out that you need the medication that’s been in your pocketbook the ENTIRE TIME.If you are unsure if your state allows this, or if you Local EMS agency can do this. Contact their local medical control and ask. If they do, Please offer to give a small talk on what the disease is and how to use the emergency kit. Most will know once they see the acto-vial, but if they do not, Please educate them. Explain to them that it can be the only thing that could save your life.
Please take the time and make sure that you have correct information on your bracelet. Secondary or Primary, the treatment in an Emergency situation is the same. So there is NO need for you to spell out if you are secondary or primary. Both get the emergency injection in case of a crisis. Both get fluid bolus, heart and blood pressure monitoring. Nothing is different when it comes to an emergency situation. If you have any questions on the wording or what to get on it. Be sure you at least have an emergency contact, That you are steroid dependent, and where your emergency injection is located.
IF you know that your local EMS agency uses the “cloud” for stored emergency info, you can spend the money to get it. But I worked for service that covered a county with over 100 sq miles, and we didn’t use it. It is unreliable and takes too much time to log in to the system, try to read the small number on your band, type it in, etc. When you can simply put the information on the band itself.
The image below sure looks like it was made by Sandra Boynton but I got it from another page on Facebook.
These tips are good for anyone who needs a little self-care – not just people with adrenal insufficiency!
What do you do for self care? Please tell me in the comments.
Each month, The Clinical Advisormakes one new clinical feature available ahead of print. Don’t forget to take the poll. The results will be published in the next month’s issue.
A 35-year-old woman is seen in the outpatient clinic for evaluation of an incidental pituitary macroadenoma. Her medical history is significant for hypertension, diabetes, hyperlipidemia, polycystic ovary syndrome, and obesity. She initially presented to the emergency department (ED) a week ago after an episode of right visual field changes that she described as waviness in her right eye and right hemibody sensory changes without motor deficits. While in the ED, she underwent a full workup for possible stroke, which was negative. Magnetic resonance imaging (MRI) of her brain without contrast revealed a 12-mm pituitary lesion; a repeat MRI with contrast was then ordered (Figure). No serum hormonal panel was available for review from ED records.
Figure. Magnetic resonance imaging of the case patient. Left image: sagittal view. Right image: coronal view with contrast. Credit: Melissa Wasilenko, MSN, RN
Upon further questioning of her medical history during the clinic visit, the patient notes that a few years ago she was attempting to become pregnant and was evaluated by her gynecologist for amenorrhea. At that time, she reportedly completed an endocrine laboratory workup that showed a slightly elevated prolactin level between 30 and 40 ng/mL (normal level in nonpregnant women, <30 ng/mL). Per the patient, the minimal elevation was not enough to concern the gynecologist and no MRI was ordered at that time. Her gynecologist recommended that she lose weight. Her menses returned to normal with weight loss. With a history of disrupted menstrual cycles, infertility, and patient reported elevated prolactin level, there is high suspicion for endocrine disruption. A complete pituitary panel is ordered again to examine the current hormone function considering the recent MRI findings. This revealed a prolactin of 33.7 ng/ml, and all other hormonal levels were within normal limits.
Because the patient reports multiple episodes of visual disturbances and the size of the pituitary adenoma on MRI, a neuro-ophthalmology referral is initiated for visual field testing and to determine if the pituitary macroadenoma is causing mass effect and compressing the optic nerve. The neuro-ophthalmologist found she had no visual field defect from her adenoma on visual field testing and believed that her visual disturbances were probably migraine in nature.
Discussion
Pituitary gland tumors are usually found incidentally on imaging studies obtained for other reasons or in workup of patients with abnormal endocrine hormone levels (both decreased and increased levels) or with symptoms of mass effect from the lesions.1 These tumors are typically benign in nature; cases with malignancy are extremely rare.1 The exact pathophysiology of pituitary adenomas remains unknown but is thought to be linked to heredity, hormonal influences, and genetic mutations.1
Pituitary tumors are commonly found in adults between the ages of 35 and 60 years of age.2,3 The estimated prevalence of pituitary adenomas varies widely by study and findings are typically based on autopsy and radiology data. Surveillance, Epidemiology, and End Results (SEER) Program data from 2004 to 2018 show an incidence rate of pituitary adenomas and pituitary incidentalomas of 4.28 ± 0.04 and 1.53 ± 0.02 per 100,000 population.4 Pituitary tumors have been found in 14.4% of unselected autopsy cases and 22.5% of radiology tests.1
The SEER data suggest that incidence rates are similar among women and men but are higher among women in early life and higher among males in later life.5 Rates of prolactinomas (prolactin-secreting tumors) and corticotropinomas (adrenocorticotropic hormone-secreting tumors; Cushing disease) are higher in women than men.6
Earlier SEER data showed a significantly higher incidence of pituitary adenomas in Black individuals compared with other racial/ethnic groups; several factors may account for this discrepancy such as the higher stroke rate in this population, which leads to a greater likelihood for brain imaging that detects incident pituitary tumors.5
Incidental findings of pituitary adenoma may be found during workup related to hormonal dysfunction (amenorrhea, galactorrhea, fertility disorders, sexual dysfunction), noticeable vision change, new-onset headaches, or imaging performed for other diagnostic purposes.7
Pituitary Types
Pituitary tumor types are differentiated by location, size, and functional status. Pituitary tumors commonly arise from the anterior portion of the gland (adenohypophysis) and rarely from the posterior portion (neurohypophysis).2 Both adenohypophyseal and neurohypophyseal tumors are commonly benign and slow-growing.1 Malignant pituitary tumors account for less than 1% of pituitary lesions and are usually metastases from breast and lung cancers.3 Adenohypophyseal carcinoma is rare, with less than 140 reported cases.2
Pituitary tumors are categorized by the size1,2:
Microadenomas (<10 mm)
Macroadenomas (>10 mm to 40 mm)
Giant adenomas (>40 mm)
Pituitary adenomas are further classified as functioning (hormone-secreting) or nonfunctioning (nonsecreting).1,6 If the adenoma is functioning, hormone levels will be found in excess. If the levels are within normal limits, a nonfunctioning pituitary adenoma is suspected.
Functioning Tumors
Approximately 65% of all pituitary adenomas are functioning tumors.2 Functioning pituitary adenomas present in various ways depending on which hormone is involved and the level of hormone secretion. Prolactinomas are the most common type of functioning adenomas followed by growth hormone-secreting and adrenocorticotropic hormone-secreting pituitary tumors. Adenomas secreting thyrotropin and follicle-stimulating hormone are less commonly found.2 Clinical features of functional pituitary adenomas are outlined in Table 1.2.8
Table 1. Clinical Features and Laboratory Findings of Functioning Pituitary Adenomas
Nonfunctioning Tumors
Approximately 20% to 30% of pituitary adenomas are nonfunctional.3 These tumors may go undiagnosed for years until the mass of the tumor starts to effect surrounding structures and causing secondary symptoms such as compression of the optic chiasm causing vision impairments.
Nonfunctioning pituitary adenomas and prolactinomas (functioning) are the 2 most common types of pituitary adenomas.2,3 The consulting clinician must understand the difference in pathology of these 2 types of lesions, what diagnostic test to order, how to interpret the test results, and which specialty to refer the patient to best on the initial workup findings.
Initial Workup
Proper baseline workup should be initiated before referring patients with incidental pituitary adenoma to a specialist. The initial workup includes imaging, blood work to determine if the pituitary adenoma is causing hormonal dysfunction, and neuro-ophthalmology referral for visual field testing to determine if the optic nerve/chiasm is impacted.
Imaging
The most accurate diagnostic modality of pituitary gland pathology is MRI with and without contrast. The MRI should focus on the hypothalamic-pituitary area and include contrasted imaging to evaluate the soft tissue within the intracranial structure.9 The coronal and sagittal views are the best to display the pituitary gland width and height and identify abnormalities.9 The MRI provides a detailed evaluation of the pituitary gland related to adjacent structures within the skull, which helps to detect microalterations of the pituitary gland.10 If a pituitary adenoma is an incidental finding on another imaging modality (such as a computed tomography scan or MRI without contrast), an MRI with and without contrast that focuses on the pituitary gland should be obtained.
Pituitary Laboratory Panel
A complete pituitary panel workup should be obtained including prolactin, thyrotropin, free thyroxine, cortisol (fasting), adrenocorticotropic hormone, insulinlike growth factor 1, growth hormone, follicle-stimulating hormone, luteinizing hormone, estradiol in women, and total testosterone in males.1 Tests should be completed in the morning while fasting for the most accurate results. For instance, normally cortisol levels drop during fasting unless there is abnormality. Table 2 below shows normal laboratory ranges for a complete pituitary panel.
Serum prolactin levels can slightly increase in response to changes in sleep, meals, and exercise; emotional distress; psychiatric medications; and oral estrogens. If the initial prolactin level is borderline high (21-40 ng/mL), the test should be repeated. Normal levels are higher in women than in men. Microadenomas may cause slight elevations in prolactin level (ie, <200 ng/mL), while macroadenomas are likely to cause greater elevations (ie, >200 ng/mL).1 Patients with giant prolactinomas typically present with prolactin levels ranging from 1000 ng/mL to 100,000 ng/mL.11
Perimetry
Pituitary adenomas may cause ophthalmologic manifestations ranging from impaired visual field to diplopia because of upward displacement of the optic chiasm. The optic chiasm is located above the pituitary gland and a pituitary tumor that grows superiorly can cause compression in this area.12 Optic chiasm compression from a pituitary adenoma commonly causes bitemporal hemianopsia.2 If the tumor volume is promptly reduced by surgical resection or medication (in the case of prolactinomas), initial vision changes due to compression may be reversible.12
Baseline and routine follow-up perimetry are important in patients with pituitary adenoma, as symptoms of optic chiasm compression may go unnoticed by patients as visual field deficits often develop gradually. Also, post-treatment perimetry assessments can be used to compare the initial testing to evaluate reversible visual field deficits. It is recommended that patients with pituitary adenomas (both function and nonfunctiong) receive neuro-ophthalmologic evaluations twice a year to ensure no visual changes have occurred.12
Referral to a Specialist
Management of pituitary adenomas requires a multidisciplinary team of specialists including endocrinologists, neurosurgeons, and neuro-ophthalmologists. The type of adenoma governs which specialist patients with incidental adenoma should see first.
Patients with functioning pituitary adenomas should be referred to an endocrinologist before a neurosurgeon. The most prevalent functioning adenomas, prolactinoma, are initially treated with dopamine agonist medications.1,6 A patient with prolactinoma would only need to see a neurosurgeon if they have a macroadenoma that is not responsive or only partially responsive to dopamine agonists therapy or is causing vision deficits related to compression of the optic chiasm.2
Patients with nonfunctioning pituitary adenomas should first be referred to a neurosurgeon to discuss surgical options versus observation. The recommended treatment for patients with nonfunctioning adenomas and clinical features of mass effect (ie, visual deficits) is surgery.1,6 If the patient is asymptomatic with no signs of visual field deficits, the neurosurgery team may recommend continued surveillance with serial imaging and serial perimetry screenings.12
The patient in the case was found to have a nonfunctioning pituitary adenoma (prolactin was 33.7 ng/mL). Neuro-ophthalmology did not find any visual field defect upon initial assessment; the patient decided to continue observation with serial imaging (MRI) and serial neuro-ophthalmology assessments. Serial imaging with MRI brain revealed slow but real progression of the pituitary macroadenoma (12 mm initially; 13 mm 6 months later; and 14 mm 1 year from initial MRI findings). Although the patient still did not have any visual field defects per the neuro-ophthalmology reassessments, the documented growth on MRI over a short period of time was enough to make the patient more amendable to surgical resection. The patient underwent trans-sphenoidal resection of the pituitary lesion approximately 16 months after discovery of the tumor.
Conclusion
A thorough workup including laboratory testing, imaging, and vision field testing is the foundation of an effective referral process for pituitary adenomas and guides which specialist is consulted first. If patients are referred before initial workup is completed, delays in care, unnecessary specialty visits, and increased overall health care costs may occur.
Melissa Wasilenko, MSN, RN, is a registered nurse at Lyerly Neurosurgery in Jacksonville, Florida. She is currently pursuing a doctorate in nursing practice with a focus in family medicine at the University of North Florida in Jacksonville.
