Adrenals Flashcards
Name the sections within the adrenals and what they produce
‘deeper you go, sweeter it gets’
From out (cortex) to in (medulla):
- Glomerulosa = mineralcorticoids (aldosterone)
- Fasciculata = glucocorticoids (cortisol)
- Reticularis = sex steroids
- Medulla = catecholamines (adrenaline, noradrenaline)
Causes of primary hyperaldosteronism
Conn’s syndrome (70% cases, young females)
Bilateral adrenal cortex hyperplasia (30% cases, older males)
Familial hyperaldosteronism
Aldosterone producing adrenal carcinoma (RARE)
What symptoms do you get in hyperaldosteronism and why?
XS aldosterone leads to increased salt and water retention by acting on Na+ channels and Na+/K+ ATPase pump in the collecting duct
Increase blood volume => hypertension
- headache, retinopathy, resistant to medication
Increased K+ secretion => hypokalaemia
- muscle weakness/cramps, polyuria, nocturia, paraesthesia
Ix for primary hyperaldosternoism
Screening:
- plasma K+ levels (low in 20% pts)
- urine K+ (high)
- plasma aldosterone (high)
- plasma aldosterone:renin ratio (high)
Confirmatory:
- salt loading, postural test, CT/MRI
- fludrocortisone suppression test (BMJ best practice; aldo increased, renin decreased)
- bilateral adrenal vein catheritisation (elevated in 1 indicates adenoma laterilised)
Tx of primary hyperaldosteronism
Laprascopic adrenalectomy = Conn’s syndrome
Spironolactone or eplerenone if side effects not tolerated = monitor serum K+, creatinine and BP
What causes Cushing’s syndrome?
Exogenous
- steroid exposure (most common cause)
Endogenous
- ACTH-dependent (80%) => pituitary adenoma, ectopic ACTH
- ACTH-independent (20%) => benign adrenaladenoma, adrenal carcinoma (rare)
Possible signs of Cushing’s
HTN Facial plethora Moon face Interscapular fat pad Proximal muscle weakness Central obesity Pink/purple striae on abdo/breast/thighs Kyphosis (due to vertebral fracture) Fractures Pigmentation in ACTH-dependent cases Ankle oedema
Ix for Cushing’s
Serum glucose
- high risk glucose
1st line high sensitivity tests
- low dose dexamethasone suppresion test (should suprress but doesn’t)
- late-night salivary cortisol
- overnight dexamethasone suppresion test (+ve is morning >50[unit])
Determine underlying cause
- ACTH- dependent => plasma ACTH, inferior petrosal sinus sampling, high dose dexamethasone suppresion test, pituitary MRI
- ACTH-independent => CT/MRI adrenals, plasma ACTH
Complications of Cushing’s
Diabetes
Osteoporosis
HTN
Pre-disposition to infections
Mx of Cushing’s
Medical
- metyrapone/ketoconazole (use pre-op or if unfit for surgery)
Surgery
- transphenoidal resection of pituitary adenoma
- ectopic ACTH; treatment directed at tumour
- adrenal adenoma/carcinoma; surgery to remove
Radiotherapy
- if persistant post-op cortisol
Complications and prognosis of Cushing’s
Surgical treatment
- CSF leakage, meningitis, sphenoid sinusitis, hypopituitarism
Radiotherapy treatment
- hypopituitarism, radionecrosis, increased risk of 2nd intracranial tumour and stroke
50% survival rate if untreated
Common to become depressed after successful treatment
How may a phaeochromocytoma present?
RARE - young-onset or resistant intractable HTN
Paroyxmal attacks
- P alpitations
- H eadaches
- E pisodic sweating
What are familial causes of phaeochromocytomas?
MEN2a (multiple endocrine neoplasm)
VHL (von-Hippel Lindau syndrome)
NF1 (neurofibromatosis 1)
Signs and sx of a phaechromocytoma
Wt loss, fever, tachycardia, pallor, postural hypotension, HTN
Sweating, headaches, dyspnoea, palpitations, constipation, epigastric, nausea, tremor, anxiety
Ix for phaeochromocytoma
24hr urine collection (sens + spec of 98&)
Plasma free (metabolites of catecholamines present)
Tumour localisation (CT>MRI, i-123 MIBG scintigraphy)
Genetic testing
Types of adrenal insufficiency
Primary => Addison’s disease (acute/insidious onset, autoimmune)
Secondary => pituitary or hypothalamic disease (decreased ACTH secretion)
Causes of adrenal insufficiency
Autoimmune
Infections (meningococcal septicaemia, TB)
Infiltration (lymphoma, amyloidosis, mets)
Inherited (ACTH mutation rec.)
Iatrogenic (after bilateral adrenalectomy, sudden cessation of long-term steroid therapy)
Signs and sx of adrenal insufficiency
Increased pigmentation (buccal mucosa, skin creases, nails, pressure points), postural hypotension, loss of body hair in women (androgen deficiency), associated with AI conditions (vitiligo)
Fatigue, weakness, myalgia, wt loss (anorexia), D&V, abdo pain, depression
Presentation of an Addisonian crisis
Hypotensive shock, tachycardic, pale, cold, clammy
= acute adrenal insufficiency (N&V, abdo pain)
= major haemodynamic collape (SHOCK)
= precipitated by stress (infection, surgery)
Ix for an emergency presentation of adrenal insufficiency
Bloods = FBC, U&Es, CPR/ESR, low glucose, blood cultures, urinalysis, culture + sensitivity
Don’t wait for results proceed to treatment
Ix for non-emergency presentation of adrenal insufficiency
9am serum cortisol (<100mmol/L)
Short synACTHen test (<550mmol/L at 30 mins)
Long synACTHen test
(identify level of HPA axis)
Identify cause (abdo CT/MRI, autoantibodies)
Mx of adrenal insufficiency for an acute and non-acute presentation
Replace deficient
Acute
- rapid IV fluid rehydration
- 50ml 50% dextrose
- IV 200mg hydrocortisone bolus
- treat precipitating cause (Abx if infection)
- MONITOR
Non-acute
GCS => hydrocortisone*
- need to increase dose in times of acute illness/stress
MCS => fludrocortisone
*if pt has hypothyroidism, give GCS before thyroxine to avoid Addisonian crisis
Complications of adrenal insufficiency
Hyperkalaemia
Death during crisis
K+ level ranges
<3.5mmol/L = hypokalaemia 5.0-6.0mmol/L = normal >7.0mmol/L = hyperkalaemia
ECG changes of hyperkalaemia
short QT interval
tented T waves
ST segment depression
SEVERE:
prlonged PR interval
absent P waves
wide QRS complex
What causes hyperkalaemia?
Renal
- HTN, DM
Low RAAS activity
- ACEi, ARB, aldosterone antagonist, adrenal failure
Systemic K+ release
- metabolic acidosis (DKA), rhabdomyolysis
Damage to the DCT
- NSAID toxicity, renal tubular acidosis
Spurious sample
- recheck bloods if clearly not viable for life
Mx of hyperkalaemia
10 10 10 50 50
1) 10ml 10% calcium gluconate (protects heart)
2) 10U Actoapid (insulin)
3) 50ml 50% glucose
4) nebulised salbutamol
5) 12-lead ECG (continuous monitoring)
2-4 => shift K+ into cells
Mx aims to block cardiotoxic effect of K+ and increase K+ uptake into cells as hyperkalaemia can cause life-threatening arrhythmias (VF)
Causes of hypokalaemia
GI loss - diarrhoea, vomiting Redistribution of K+ into cells - beta agonists - metabolic alkalosis Renal loss - excess cortisol, hyperaldosteronism Decreased K+ uptake - anorexia nervosa
Clinical features when K+<3.0mmol/l
Muscle weakness and spasm
Cardiac arrhythmia
Polyuria and polydipsia (nephrogenic DI)
Mx of hypokalaemia
- 0-3.5mmol/L
- oral potassium chloride (SanDok)
- recheck in 48 hrs
- treat underlying cause
<3.5mmol/L
- IV potassium chloride
- max infusion rate 10mol/hr as peripheral irritant
What defines PCOS?
3 main features:
1) hyperandrogenism; hirsutism, acne
2) oligo/amenorrhoea
3) polycystic ovaries on USS
Presentation of PCOS
Associated with obesity, insulin resistance, TIIDM, infertility (most common cause of infertility)
Acne, menstrual irregularities, male-pattern hair loss, wt gain, infertility, high BMI, hirsutism, acanthosis nigricans (thickening and hyperpigmentation of skin in axilla and neck; sign of severe insulin resistance)I
Ix for PCOS
Bloods - increased LH, LH:FH ratio, testosterone, androstenedione + DHEA-S - decreased sex hormone binding globulin Transvaginal USS - increased no. of ovarian follicles - increase in ovarian volume
A 52-year-old man presents to the GP with an 8-year history of hypertension that has been difficult to control with antihypertensive medicines. His symptoms include frequent headaches, nocturia (3-4 times per night), and feeling tired. He has no other past medical history. On examination, his BP is 158/93mmHg, with no other remarkable findings.
What is the most likely diagnosis?
A – Chronic hypertension B – Phaeochromocytoma C – Primary hyperaldosteronism D – Addison’s disease E – Diabetes mellitus
C - Primary hyperaldosteronism
A 32-year-old woman presents to the GP complaining of weight gain and stretch marks on her stomach. She says she also feels weaker and finds that she bruises more easily than in the past. Her blood pressure today is 142/94 mmHg. On examination, you notice she has ankle oedema, as well as a large waist circumference and prominent purple striae on the abdomen.
What is the most likely diagnosis?
A – Metabolic syndrome B – Primary hyperaldosteronism C – Obesity D – Cushing’s syndrome E – Polycystic ovarian syndrome
D - Cushing’s syndrome
An anxious 27-year-old woman presents to the urgent care centre. She tells you she’s been having terrible headaches for several months which come and go at random intervals. During the episodes she also has palpitations and feels very sweaty. She has no past medical history, however her father had thyroid cancer a few years ago. On examination her BP is 215/117 mmHg and she is tachycardic.
What is the most likely diagnosis?
A – Phaeochromocytoma B – Resistant hypertension C – Addisonian crisis D – Thyroid cancer E – Pituitary tumour
A - Phaeochromocytoma
A 43-year-old man has a 3-month history of increasing fatigue and anorexia. He has lost 5.5 kg and noticed increased skin pigmentation, otherwise he has been healthy. Family history includes diabetes and thyroid problems. On examination his BP is 106/82 mmHg (supine) and 92/60 mmHg (sitting). There is diffuse pigmentation of his skin which is more pronounced in the mouth, palmar creases, and knuckles.
What is the most likely diagnosis?
A – Adrenal insufficiency B – Haemochromatosis C – Hyperthyroidism D – Malignancy E – Vitamin deficiency
A - Adrenal insufficiency
Which of the following is not a cause of hypokalaemia?
A – Vomiting B – Anorexia Nervosa C – Conn’s syndrome D – Rhabdomyolysis E – Salbutamol
D - Rhabdomyloysis
Which of the following is the initial step in management of hyperkalaemia?
A – 10U actrapid B – 10ml 10% calcium gluconate C – 50ml 50% glucose D – Nebulised salbutamol E – 20ml SandoK
B - 10ml 10% calcium gluconate
A 19-year-old female presents to the GP complaining of an excess of facial hair. She currently waxes her upper lip and chin twice a week and has also noticed hairs on her back and abdomen. Her periods have always been irregular (every 2-3 months) and the facial hair is affecting her social life, leaving her feeling very down.
What is the most likely diagnosis?
A – Hypothyroidism B – Cushing’s disease C – Gonadotrophin-secreting tumour D – Chromosomal abnormality E – Polycystic ovary syndrome
E - Polycystic ovary syndrome
A 40 year old female presents to the GP with chronic fatigue, myalgia and
depressive type symptoms. On examination you notice
hyperpigmentation of the buccal membrane. Routine blood tests reveal
a hyponatraemia and hyperkalaemia.
Which of the following investigations should be done?
- Low dose dexamethasone suppression test
- High dose dexamethasone suppression test
- Short SynACTHen test
- TRH stimulation test
- Glucose tolerance test
- short synACTHen test
A patient with Addison’s disease is found unconscious on the bus. She is
brought to the A+E where is she found to be hypotensive and slightly
feverish. Routine blood tests are sent off which are normal except for
the U+E’s.
Na+ = 130 mmol/L. K+ = 5.4. Urea = 9mmol/L. Creatinine = 80
micromole/L.
What is the most appropriate immediate therapy?
- IV hydrocortisone and fludrocortisone
- IV hydrocortisone
- IV fludrocortisone
- Start sepsis 6
- Give IV fluid bolus
- IV hydrocortisone
A 58 year old man attends the GP concerns about the stretch marks on
his stomach. On examination, there are purple striae on his abdomen
and you notice he is overweight with adipose tissue predominantly
centrally and subscapular. You send for a dexamethasone supression
test with come back with the following:
Initial 9am cortisol = 600 nM. 48 hours later: cortisol = <50 nM.
What of the following is the most likely cause?
- Cushing’s syndrome
- Alcohol excess
- Cushing’s disease
- Hypothyroidism
- Addison’s disease
- Alcohol excess
You are a surgeon in an Endocrine MDT. The next patient is presented
with confirmed Cushing’s syndrome. A pituitary MRI shows a pituitary
lesion. You look at the lesion and think “I can remove that”.
What is the most appropriate next step?
1. Tell everyone you will book the patient in for surgery and remove the
tumour.
2. Refer the patient for inferior petrosal sinus sampling
3. Ask for a high dose dexamethasone suppression test to be done
- Ask for a high dose dexamethasone suppresion test to be done
A 38 year old female has a routine blood test for health insurance. She is
referred to her GP after a mild hypokalaemia was detected. She
reports some fatigue and lethargy but no other symptoms. Her
examination is normal except for a blood pressure of 150/90.
What is the most appropriate 1st investigation?
- Fludrocortisone suppression test
- Thyroid function tests
- Aldosterone/Renin Ratio
- Renal duplex ultrasound
- Low dose dexamethasone suppression test
- Aldosterone/renin ratio
A 35 year old man has headache, palpitations, and sweating.
Examination reveals hypertension, which is paroxysmal in nature.
Additionally, there are café au lait spots. A diagnosis of
phaeochromocytoma is suspected.
Which investigation would provide
confirmation?
A. Thyroid Stimulating Immunoglobulin (TSI) Antibody Levels
B. Thyroid Function Tests (TSH, Free T4, and Total T3 Levels)
C. 24-Hour Urinary Catecholamine and Metanephrine Levels
D. Plasma Aldosterone to Plasma Renin Activity Ratio (ARR)
C. 24-hour Urinary Catecholamine and metanephrine levels
A nurse bleeps you (the on-call SHO) at 7pm as a patients blood tests
have come back showing a severe hyperkalaemia of 7.4 mmol/l. You
burst into the ward and find the patient. He responds cheerily to you
and asks how you are doing.
What is the best appropriate next step?
- Ask the nurse to do an ECG on him
- Do a venous blood gas
- Repeat the blood test
- Give 10ml 10% calcium gluconate
- Warm up the defibrillator
- Repeat the blood test
A 22 year old female presents to the GP with excessive hair growth along
persistent acne. She mentions that’s she’s been having painful
irregular periods for many years and would also like treatment for that.
What is the most likely diagnosis?
- Physiologically normal
- PCOS
- Hypothyroidism
- Delayed puberty
- Hyperthyroidism
- PCOS