Concept and Etiology:
Cushing syndrome is an endocrine disorder in which the pituitary gland produces too much
adrenocorticotropic hormone (ACTH). This over production is due to a benign tumor
called an adenoma which is located on the pituitary gland that causes the pituitary gland to
malfunction and create the excess ACTH. ACTH stimulates the production of cortisol in
the adrenal glands, so when there are excess levels of ACTH, there is excess levels of
cortisol. Having Cushing syndrome deviates from the definition of health, because your
body is no longer maintaining homeostasis and keeping hormones regulated.
Classification:
Cushing syndrome is classified by being either ACTH dependent or ACTH independent,
and then sub categorized under one of the two major categories:
ACTH dependent:
• Cushing's disease
• Ectopic ACTH syndrome
• Ectopic corticotropin-releasing hormone syndrome
ACTH independent:
• Iatrogenic
• Adrenal adenoma
• Micronodular hyperplasia
• Macronodular hyperplasia
(Kirk, Hash, Katner, Jones, 2000)
Clinical Manifestations:
SIGNS:
• Weight gain and fatty tissue deposits, particularly around the midsection and upper
back, in the face (moon face), and between the shoulders (buffalo hump)
• Pink or purple stretch marks (striae) on the skin of the abdomen, thighs, breasts, and
arms
• Thinning, fragile skin that bruises easily
• Slow healing of cuts, insect bites and infections
• Acne
• Thicker or more visible body and facial hair (women)
• Skin darkening
• Bone loss, leading to fractures over time
• In children, impaired growth
SYMPTOMS:
• Severe fatigue
• Muscle weakness
• Depression, anxiety, and irritability
• Loss of emotional control
• Cognitive difficulties
• New or worsened high blood pressure
• Headache
• Loss of sexual interests
•
Diagnostic Tests:
• Physical exam looking for stretch marks, bruises, or hump
• 24-hour urinary free cortisol test: For this test, you’ll be asked to collect your urine
over a 24-hour period. The levels of cortisol will then be tested.
• Salivary cortisol measurement: In people without Cushing’s syndrome, cortisol
levels drop in the evening. This test measures the level of cortisol in a saliva sample
that’s been collected late at night to see if cortisol levels are too high.
• Low-dose dexamethasone suppression test: For this test, you’ll be given a dose of
dexamethasone late in the evening. Your blood will be tested for cortisol levels in
the morning. Normally, dexamethasone causes cortisol levels to drop. If you have
Cushing’s syndrome, this won’t occur.
After you receive the diagnosis of Cushing’s syndrome, your healthcare provider must still
determine the cause of the excess cortisol production. Tests to help determine the cause
may include:
• Blood adrenocorticotropin hormone (ACTH) test: Levels of ACTH in the blood are
measured. Low levels of ADTH and high levels of cortisol could indicate the
presence of a tumor on the adrenal glands.
• Corticotropin-releasing hormone (CRH) stimulation test: In this test, a shot of CRH
is given. This will raise levels of ACTH and cortisol in people with pituitary tumors.
• High-dose dexamethasone suppression test: This is the same as the low-dose test,
except that a higher dose of dexamethasone is used. If cortisol levels drop, you may
have a pituitary tumor. If they, don’t you may have an ectopic tumor.
• Petrosal sinus sampling: Blood is drawn from a vein near the pituitary and from a
vein far away from the pituitary. A shot of CRH is given. High levels of ACTH in
the blood near the pituitary can indicate a pituitary tumor. Similar levels from both
samples indicate an ectopic tumor.
• Imaging studies: These can include things like CT and MRI scans. They’re used to
visualize the adrenal and pituitary glands to look for tumors.
(Kahn & Biggers, 2020).
Concept and Etiology:
Diabetes Mellitus is an endocrine disorder characterized by hyperglycaemia (high serum
glucose levels) resulting from defects in insulin production, insulin action, or both. DM can
occur in three forms—type 1, type 2, and gestational diabetes—each with its own
pathogenesis. Chronic diabetes conditions include type 1 diabetes and type 2 diabetes.
Potentially reversible diabetes conditions include prediabetes and gestational diabetes.
Prediabetes occurs when your blood sugar levels are higher than normal, but not high
enough to be classified as diabetes. And prediabetes is often the precursor of diabetes
unless appropriate measures are taken to prevent progression. Gestational diabetes occurs
during pregnancy but may resolve after the baby is delivered. (Story, L. 2018, pp. 312)
Classification:
The majority of diabetic patients are classified into one of two broad categories: type 1
diabetes mellitus, or type 2 diabetes mellitus, which is characterized by. In addition,
women who develop diabetes during their pregnancy are classified as having gestational
diabetes.
• Type 1 diabetes (which is caused by an absolute or near absolute deficiency of insulin)
• Type 2 diabetes (the presence of insulin resistance with an inadequate compensatory
increase in insulin secretion)
• Gestational diabetes mellitus (GDM) (diabetes diagnosed in the second or third
trimester of pregnancy that is not clearly overt diabetes)
• Specific types of diabetes due to other causes, e.g., monogenic diabetes syndromes
(such as neonatal diabetes and maturity-onset diabetes of the young [MODY]), diseases of
the exocrine pancreas (such as cystic fibrosis), and drug- or chemical-induced diabetes
(such as in the treatment of HIV/AIDS or after organ transplantation)
(Mayo Clinic, 2018)
Clinical Manifestation z
Hyperglycaemia
• Glucosuria (glucose is excreted in the urine in an attempt to lower serum levels)
• Polyuria (increased urine output because of the osmotic effects of the glucosuria)
• Polydipsia (increased thirst because of the dehydration caused by the increased urine
output)
• Polyphagia (increased appetite because of the energy loss as glucose is excreted)
• Weight loss (from increased fat catabolism)
• Blurred vision (excessive glucose changes the shape and flexibility of the lens of the
eye, distorting the ability to focus and causing blurred vision)
• Fatigue (because of a lack of an energy source)
• z Nausea, vomiting, and abdominal pain (associated with sudden onset of type 1 diabetes)
Included in the manifestations mentioned above are 3 classic signs of diabetes mellitus.
They are referred to as the three P’s:
• Polyuria
• Polydipsia Polyphagia
(Story, L. 2017) (NIH.GOV)
Diagnostic Tests:
Diagnostic procedures include a history, physical examination, urinalysis (to detect the
presence of glucose), fasting blood glucose test, oral glucose tolerance test, random blood
glucose test, hemoglobin A1c (HgbA1c; an average of glucose control for the previous 2–3
months), blood pressure measurement, and cholesterol panel.
(American Diabetes Association, 2015)
REFERENCES:
Story, Lachel. Pathophysiology: A Practical Approach (pp. 312-315) Available from: MBS
Direct, (3rd Edition). Jones & Bartlett Learning, 2017.
Mayo Clinic (2018). Diabetes – Symptoms and Causes. Mayo Clinic. Retrieved November
15, 2021, from
https://www.mayoclinic.org/diseases-conditions/diabetes/symptoms-causes/syc-20371444
Classification of Diabetes Mellitus - NCBI Bookshelf (nih.gov). Retrieved November 15,
2021, from
https://www.ncbi.nlm.nih.gov/books/NBK279119/
American Diabetes Association (2015). Diabetes Care. Retrieved November 15, 2021, from
https://care.diabetesjournals.org/content/38/Supplement_1/S5
Kahn, A., & Biggers, A. (2020, August 28). Everything you need to know about
Cushing's syndrome. Healthline. Retrieved November 14, 2021, from
https://www.healthline.com/health/cushings-syndrome.
Kirk, L., Hash, R., Katner, H., & Jones, T. (2000). Cushing's Disease: Clinical
Manifestations and Diagnostic Evaluation. American Family Physician, 1119–1127.
Retrieved November 14, 2021, from https://www.aafp.org/afp/2000/0901/p1119.html.
