Addisons + secondary adrenal Insufficiency Flashcards
Most common cause of primary adrenal insufficiency?
Autoimmune adrenalitis
What are the Infectious causes of adrenal insufficiency?
TB, CMV, HIV
What are the cancer types that metastasise to the adrenal glands?
Lung, breast carcinoma
Name the condition with adrenal haemorrhage in sepsis?
Waterhouse-Friderichsen syndrome
Why does Addison’s cause hyperpigmentation?
Excess ACTH → excess MSH
Electrolyte imbalances in Addison’s?
↓ Na+
↑ K+
acidosis, hypoglycemia
Why does Addison’s cause salt craving?
Low aldosterone → Na+ loss
Key symptoms of Addison’s?
(1) Weakness
(2) Fatigue
(4) Weight loss
(5) N+V
(6) Low BP
(7) Abdominal pain
What are the signs of hyperpigmentation?
Tanned skin, dark buccal mucosa, palmar creases
1st-line test for Addison’s?
Short Synacthen test
ACTH & aldosterone levels in Addison’s?
↑↑ ACTH
↓ aldosterone
↑↑ renin
When should Addison’s be suspected in blood tests?
Hyponatremia + hyperkalemia
What is used for cortisol replacement?
Hydrocortisone
What is used for aldosterone replacement?
Fludrocortisone
Why must steroids not be stopped suddenly?
Risk of adrenal crisis
What are the “sick day rules”?
increase steroid replacement when unwell or undergoing other stress
What is the 1st-line test for Addison’s disease?
Short Synacthen Test
= checks ACTH response
How is the Short Synacthen Test performed?
Measure plasma cortisol before and 30 mins after IV/IM ACTH injection
What is a normal cortisol response in the Short Synacthen Test?
(1) Baseline >250 nmol/L
(2) Post-ACTH >550 nmol/L
What is secondary adrenal insufficiency?
Lack of ACTH production by the pituitary gland
= ↓ cortisol
What is tertiary adrenal insufficiency?
Lack of CRH secretion by the hypothalamus
= ↓ ACTH → ↓ cortisol
What is the most common cause of secondary/tertiary adrenal insufficiency?
Iatrogenic
(long-term exogenous steroid use)
(1) → suppresses CRH & ACTH
(2) → adrenal atrophy
What are the other causes of secondary adrenal insufficiency?
(1) Pituitary/hypothalamic tumors
(2) Surgery
(3) Radiotherapy
How does iatrogenic steroid use cause adrenal insufficiency?
Chronic steroids inhibit CRH & ACTH
= Leading to adrenal atrophy
The adrenal glands fail to produce cortisol even if ACTH is given
Why is aldosterone normal in secondary/tertiary adrenal insufficiency?
Aldosterone is regulated by RAAS, not ACTH, so it remains intact
How does secondary/tertiary adrenal insufficiency differ from Addison’s disease?
(1) No hyperpigmentation (low ACTH)
(2) No salt craving
(3) normal aldosterone
(4) No hypotension or hyperkalemia
Why is skin pale in secondary adrenal insufficiency?
No excess ACTH, so no MSH activation
= no hyperpigmentation
What is the gold standard test used to diagnose secondary/tertiary adrenal insufficiency?
Insulin tolerance test
= checks cortisol response to hypoglycemia
What test is used to differentiate between secondary and tertiary causes
CRH stimulation test
What is the treatment for secondary/tertiary adrenal insufficiency?
Hydrocortisone
= Cortisol replacement
Why is fludrocortisone not needed in secondary or tertiary adrenal insufficiency?
Aldosterone production is intact
= RAAS regulation
What should happen to a patient’s normal dose of steroids whilst they are unwell?
They should be doubled during the course of the illness
How is the diagnosis of Addison’s disease confirmed?
Short synacthen test
What dose of IV Hydrocortisone should be administered acutely during an Addisonian crisis?
100mg IV
Which can be followed by 100mg IM 6 hourly
What medication can be used to help the body retain salt?
Fludrocortisone
What happens to potassium levels in Addison’s disease?
They go up (Hyperkalaemia)
Which autoimmune dermatological condition is associated with Addison’s disease?
Vitiligo
What electrolyte abnormalities may you find in an Addisonian crisis?
- Hyponatraemia
- Hyperkalaemia
- Hypoglycaemia
- Hypercalcaemia
- Raised urea
What is the best initial treatment of an Addisonian crisis?
IV fluids and IV steroids
What is the name given to adrenal haemorrhage following meningococcal sepsis?
Waterhouse-Friedrichson syndrome
What is the peak cortisol cut off value expected following a short synacthen test that you would expect in a person with normal adrenal gland function?
ie, what level of cortisol needs to be achieved to be over?
550 nmol/l
What is the screening test for adreno-cortical insufficiency?
9AM cortisol
Which type of steroid is used in the management of an Adrenal crisis?
Hydrocortisone
For patients with known adrenal insufficiency, what medication should they keep on hand in case of emergency?
Ef-Cortisol injection
low sodium name
hyponatremia
high potassium name
hyperkalemia
A 32-year-old woman presents with fatigue, weight loss and hyperpigmentation. Her blood pressure is low, and she has a craving for salty foods.
What is the initial investigation?
9am serum cortisol
(1) If 9 am cortisol is low (<100 nmol/L) → Adrenal insufficiency is likely, and a Synacthen test is done for confirmation
(2) If 9 am cortisol is borderline (100–450 nmol/L) → A Synacthen test is needed to assess adrenal function
(3) If 9 am cortisol is >450 nmol/L, adrenal insufficiency is excluded, and no further testing is needed
A 50-year-old woman attends A&E feeling unwell with gastroenteritis. She has a history of rheumatoid arthritis and is on maintenance Prednisolone 10mg OD which she has not been able to take for the last three days.
What general advice should be given with regards to steroids and intercurrent illness?
Double steroid dose
A 63-year-old female presents to her GP with confusion, weakness and dizziness. On examination, it is noted that she is tanned. The GP suspects Addison’s disease.
What is the most likely underlying aetiology?
Autoimmune
A 45-year-old man is treated for Addison’s disease with Hydrocortisone (replacement glucocorticoid) and Fludrocortisone (replacement mineralocorticoid)
In which part of the adrenal gland is the mineralocorticoid produced?
Zona glomerulosa
A 42-year-old male presents to the GP feeling weak, tired and faint. On examination, the GP notes he appears tanned. His GP suspects Addison’s disease
What first-line investigation should be ordered next?
9AM cortisol
A 75-year-old woman with a history of polymyalgia rheumatica is found collapsed by her partner. Her partner remarks that she is likely exhausted after her holiday
- Low sodium
- High potassium
- High urea
- Low fasting glucose
What is the most likely cause of her collapse?
Adrenal crisis
What are meningococcal septicaemia symptoms?
Patient has Waterhouse-Friderichsen syndrome
(1) Rash
(2) Neck stiffness
(3) Headache
(4) Fever
A 60-year-old man is brought to the emergency department with abdominal pain and vomiting. On assessment, he is confused and has a blood glucose level of 3.2mmol/L (normal range 3.5-5.5 mmol/L) and blood pressure of 80/56. He has a past medical history of Addison’s disease. The patient is treated urgently for an Addisonian crisis. His daughter is also with him and wants to know more about his condition.
An Addisonian crisis is caused by the body’s inability to produce which hormone?
Cortisol
A 28-year-old British lady has been suffering from weakness, abdominal pain and vomiting recently. Her skin has become slightly darker. Her blood studies suggest hyponatremia and hyperkalemia.
Given the likely diagnosis, what is the commonest cause?
Auto-immunity
A 45-year-old man presents to his GP with a 6-month history of fatigue and muscle weakness. He also states to has lost about 5kg in weight over the same period. He has a past medical history of Hashimoto’s disease for which he takes levothyroxine daily.
On examination, he is noted to have hyperpigmentation of the skin and buccal mucosa.
A short Synacthen test confirms the diagnosis, and he is started on hydrocortisone.
What dosing regimen should be followed?
Majority of dosing in the morning, the remainder in the evening
A 42-year-old man presents to his general practitioner with a two-day history of flu-like symptoms, including a dry cough and lethargy. He was diagnosed with Addison’s disease three months ago and recalls being advised to seek medical attention if he became unwell to adjust his medication. His current medication regimen includes 20 mg hydrocortisone, 100 mcg of fludrocortisone each morning and 10 mg hydrocortisone in the evening.
How should his medication regimen be modified?
Double morning and evening hydrocortisone dose
A 40-year-old female presents to your clinic with vomiting for the past 24 hours. The last time she vomited was 10 minutes ago and she still feels nauseous now. She explains that she went to a barbeque the previous day and ate sausages, which she is worried were not cooked properly. She has a past medical history of Addison’s disease for which she takes oral hydrocortisone and fludrocortisone daily.
What is the most appropriate advice to give to this patient?
Take IM hydrocortisone until her vomiting stops
In an addisonian crisis, what is required to take?
IV hydrocortisone
ACTH stimulation test is another name for what?
The short synacthen test
A 28-year-old Welsh woman attends her GP with a month history of fatigue and depression. Her blood pressure is 124/80 mmHg lying and 92/58 mmHg standing. Blood tests reveal a mild hyponatraemia and mild hyperkalaemia. The GP arranges a short synacthen test and the results are as follows: (expected 30-minute level >580 nmol/l)
Baseline cortisol 300 nmol/l
30 minute cortisol 350 nmol/L
What is the most likely underlying cause?
Autoimmune adrenalitis
= This woman has Addison’s disease as she has failed a short synacthen test
A 30-year-old man is found unconscious in the street and brought to the emergency department. As part of his A-E workup, a blood gas is sent.
pH 7.23
pCO2 5.5kPa
HCO3 19mmol/L
pO2 10kPa
The team calculated his anion gap and it is normal
What would have caused these results and wy?
Addison’s disease causes a metabolic acidosis with a normal anion gap
A 45-year-old woman presents with a 3-month history of fatigue, weight gain and menstrual irregularities.
Lab results reveal the following:
Na+ 130 mmol/L (135 - 145)
K+ 4 mmol/L (3.5 - 5.0)
Urea 5 mmol/L (2.0 - 7.0)
Creatinine 84 µmol/L (55 - 120)
Plasma osmolality 268 mOsm/kg (285-295 mOsm/kg)
Urine osmolality 562 mOsm/kg (500-800 mOsm/kg)
Urine Na+ 28 mmol/L (<20 mmol/L)
What is the most likely cause of these electrolyte abnormalities?
Hypothyroidism causes a euvolaemic hyponatraemia
Metabolic alkalosis + hypokalaemia equals what
vomiting
A 52-year-old man who has recently moved to the UK from India presents to his General Practitioner with fatigue and weight loss. He also reports a poor appetite (although he has been craving salty foods) and a reduction in his libido. On examination, he has hyperpigmentation over his palmar creases and a scar on his chest. Initial blood tests reveal hyponatraemia and hyperkalaemia. Further testing shows a low morning cortisol and a high plasma adrenocorticotrophic hormone (ACTH). A diagnosis of adrenal insufficiency is expected
What is the most likely underlying cause?
HIV, CMV, TB
What are the two main causes of adrenal crisis?
- Underlying adrenal insufficiency
- Sudden withdrawal of long-term glucocorticoid therapy
Why can stopping steroids suddenly cause an adrenal crisis?
Long-term steroid use suppresses ACTH production via negative feedback
Sudden withdrawal leaves the body unable to produce sufficient cortisol in response to stress
What is the first step in managing an adrenal crisis?
Rehydration with IV 0.9% sodium chloride – start with a rapid bolus
What steroid is used in adrenal crisis management?
100 mg IV hydrocortisone, followed by a continuous infusion or IM injections every 6 hours
Are investigations required before treating suspected adrenal crisis?
NOPE
