16 - obesity and Cushing's syndrome Flashcards
What is BMI?
Kg/ height2
What is overweight in BMI?
Greater than 25
What is obesity?
Greater than 30
Add 1 grade per increase of 5 BMI
When is a patient eligable for bariatric surgery?
BMI > 35 with comorbidites OR BMI > 40 with no comorbidities
and has demonstrate weight loss
What is olistat and when is it indicated?
lipase inhibitor in the gut
for BMI > 30
Patients must demonstrate 5% reduction in weight within 5 months
What test are good in order to screen for cushing’s syndrome?
Overnight dexamethsone supression test
24 hour urinary free cortisol
A patients shows that they have increased cortisol in urin/ raised cortisol after dexamethasone supreesion test. What is the next investigation?
ACTH test
ACTH come back and shows high levels of ACTH. What does this indicate and what is the next most appropraite investigaiton?
A ectopic or pituitary tumour.
Next use petrosal venous sampling. Sometimes pituitary MRI can be used.
If ACTH test came back and showed low ACTH what is the likely cuase and what is the next most appropriate investigation?
Adrenal cause - hyperplasia
Do abdo CT
If petrosal venous sampling showed high levels of ACTH: what would be the likely cause and what is the next most appropriate investigation?
Pituitary adenoma
Pituitary/ head MRI
If petrosal venous sampling showed low levels of ACTH: What is the likely cause and what is the next most appropriate investigation?
Ectopic ACTH release
Do CXR as small cell carcinoma of the lung is a common cause
A patient has hyponatraemia, what infomation do you need to know and in what order?
1st serum osmolority
2nd asses fluid status
3rd urine osmolarity
A patient is hyponatraemic with normal to high serum osmolarity. What could be the cause?
psuedo-hyponatraemia
What is pseudohyponatraemia?
high protein or lipids in serum
Patient is hyponatraemic, hypotonic with hypovolaemia. What is test next?
If low sodium this indicates renal losses.
If high sodium then this indicates extra renal cause: D&V etc…
Patient is hyponatraemic, hypotonic with eurovolaemia and has a high urine osmolality. What could this indicate?
Adrenal insufficiency
SIADH
Patient is hyponatraemic, hypotonic with eurovolaemia and has a low urine osmolality. What could this indicate?
Polydipsia, are they a psychiatric patient
Patient is hyponatraemic, hypotonic with hypervolaemic and has a high urine sodium. What could this indicate?
renal failure
When should a patient carry a steroid card?
If they take steroids more than 3 times a week
What is Nelsons syndrome?
Pituitary adenoma which has developed after bilateral adrenolectomy resulting in raised ACTH.
What is Pichwichian syndrome?
Hypoventilation due to obesity
Waterhouse-frederichsen syndrome
Adrenal failure due to heamorrage into the aderenal gland. This is commonly due to infection or sepsis
What is Metryaprone?
Supressors cortisol production. Can be used for diagnosis as well as managment. Increased ACTH after consumption ind.icates pituitary adenoma where as the same ACTH would indicate ectopic ACTH release
What does normal creatinine and high urea indicate?
dehydration
What is the management during an addisonian crisis?
- Treat hyperkaleamia + ECG
- 100mg IV hydrocotisone
- fluid challenge - 500ml 0.9% saline
- blood glucose
- consider infection