In station 5 you may be asked to assess a patient with fatigue, muscle weakness, weight gain, new hypertension or diabetes, change in appearance etc.
HISTORY (3 minutes)
- Timing Questions: since when, getting worse etc.
- Cushing’s history:
- Feeling weak eg. difficulty getting out of chair/climbing stairs
- Easy bruising, stretch marks, thin skin
- BP increase
- Weight gain, increase appetite
- Change in face- acne, hair growth, round, plethoric
- Thirst/polyuria/polydipsia/recent blood sugar (Diabetes)
- Back pain, pain in joints, fractures
- Periods, erection, sex drive
- Mood, insomnia, irritability
- Infections eg. skin infections, urine infections, thrush
- Fatigue/tiredness/lethargy
- Source of cushings syndrome:
- Pituitary: Visual change/headache
- Iatrogenic: steroid use
- Adrenal- abdominal pain
- Ectopic- lung cancer questions eg. haemoptysis, chest pain, cough
- PMH- difficult to control blood pressure, osteoporosis, conditions which are treated with steroids
- Dx – steroids now or recently or in past. Including steroid creams, inhalers, nasal sprays, injections. What for? Dose, route, frequency
- Fx
- Sx and impact of symptoms on life
EXAMINATION (3 minutes)
- Note the patients size/weight, look for features of arthritis, COPD, skin disease (reason for being on long term steroids)
- Hands and Arms: thin, bruised, hands for fingerprick blood glucose marks, carpal tunnel release scars, clubbing, tar staining, thenar atrophy, weakness of thumb abduction, reduced sensation of lateral 3.5 fingers, request a BP, armpits for acanthosis nigricans
- Face and neck: acne, plethora, facial fullness, hirsutism, acanthosis nigricans
- Test for proximal myopathy: stand from sitting with arms crossed
- Back: palpate for spinal tenderness, check for kyphosis (osteoporosis) and interscapular fat pads
- Quick CVS, Resp (including lymph nodes), Abdo (striae, adrenalectomy scars)
- Examine Visual fields (bitemporal hemianopia)
ICE + EXPLANATION (2 minutes)
A suggested explanation is as follows:
“I’d like to test for a condition called Cushing’s syndrome. This is when there is a high level of steroid hormone in the body. The most common cause is a small tumour in the pituitary gland in the brain which is making excess of a hormone which makes your adrenal glands on top of your kidneys make too much steroid hormone (you could draw a picture to help explanation). It can be removed by surgery. We need to collect all your urine in 24 hours to see if the level of steroid hormone is high. Depending on the results you might need further tests such as a brain scan. I will refer you to an endocrinologist (a hormone doctor)”
OR
“I suspect your symptoms are secondary to the steroids which you have been taking for your rheumatoid arthritis/ fibrosis etc. I’ll need to liaise with your rheumatologist/respiratory physician to see if we can slowly reduce your steroid dose and start steroid-sparing agents. It is dangerous to suddenly stop steroids”
OR
“I’m worried that this could be lung cancer because of your long smoking history and coughing up blood. Some lung cancers make hormone-like substances which cause problems with other organs/tissues even though the cancer has not spread here. We need to start by doing some tests such as a CXR and possible CT scan of your chest. I will refer you to one of our lung specialists”
VIVA
Cushing’s syndrome- any condition that causes increased glucocorticoid levels and loss of normal feedback mechanisms of the hypothalamic-pituitary-adrenal (HPA) axis
20-40 year old females are most commonly affected
*** most often iatrogenic secondary to exogenous steroids***
When not iatrogenic:
- 80% Pituitary Microadenoma (Cushing’s disease) secretes ACTH which stimulates the adrenals. Can be part of MEN1.
- 20% Adrenal adenoma/carcinoma/hyperplasia (cortisol secretion)
OR
Ectopic ACTH syndrome from non-endocrine tumours eg. small cell lung cancer, bronchial carcinoid, pancreas, ovarian, medullary thyroid cancer, phaeochromocytoma
Pseudo-Cushing’s- alcoholism, obesity, depression, pregnancy, poorly controlled diabetes. Get symptoms and signs and abnormal hormone levels but HPA normal. Normalises if treat the cause.
Investigations:
BP, blood glucose/Hba1c, lipid profile, ECG (LVH), U+E (low K+), FBC (WCC for infection), urine dipstick (glucose), CXR (underlying lung lesion), Echo (if features of heart failure)
Screen with 24 hour urinary free cortisol (increased)/ overnight dexamethasone suppression test (failure to suppress cortisol)
If raised cortisol on screening, do low dose dexamethasone suppression test (in pseudo-cushing’s cortisol suppresses)
If not suppressed on low dose dexamethasone suppression testing, do high dose dexamethasone suppression test
If high dose dexamethasone test suppresses cortisol, suspect a pituitary tumour and do MRI pituitary
If high dose dexamethasone test fails to suppress, do ACTH level at 9am. If high, suspect ectopic ACTH secretion and do CT chest abdomen pelvis. If low, suspect adrenal tumour and do adrenal CT.
Treatment:
First line for pituitary tumour = transphenoidal hypophysectomy (80% cure)
If surgery fails: cabergoline, pasireotide, metyrapone/ketoconazole (antiadrenocortical drugs) +/- pituitary irradiation
Remove adrenal and ectopic tumours surgically. Ectopic ACTH-secreting tumours may respond to somatostatin analogue treatment
Myopathy, menstrual irregularities, hypertension, osteoporosis, mood, diabetes may improve but may not disappear. Weight gain and appearance may partially improve.
Written by Dr Sarah Kennedy
Resources used to white this document include those used on the references section of this webpage and also:
https://www.uptodate.com/contents/overview-of-the-treatment-of-cushings-syndrome?source=search_result&search=cushing&selectedTitle=3~150