ENDOCRINOLOGY Flashcards
Causes of thyroid cancer
ionising radiation exposure
genetic- papilary thyroid associated with RET and NTRK1
types of thyroid cancer and the cells they arise from
follicular epithelial cells:
papilary (70-85%)
follicular
parafollicular āCā cells:
medullary
undifferentiated:
anaplastic
where do papilary thyroid cancers metastasise
via lymphatics to regional lymphnodes to lungs and bone
histological features of papillary thyroid cancers
intranuclear cytoplasmic inclusions (orphan annie eyes)
calcified psammoma bodies
how do follicular thyroid cancers metastasise
haematological spread
epidemiology of follicular thyroid cancer
2nd most common (10-15)
peak age 40-60yrs
management of papillary and follicular thyroid cancer
thyroidectomy (complications: damage to laryngeal nerve and hypoparathyroidism)
post op thyroxine
high risk pts, post of rodio-iodine ablation
how does raadio iodine treat hyperthyroidism
the iodine is taken up by thyroid follicular cells and this causes cell death by emission of beta rays
causes of:
hypernatraemia
D&V, burns
diabetes insipidus and unable to drink sufficiently
hyperadrenalism
causes of:
hyponatraemia
hypovolaemic:
dehydration eg. D&V
low salt diet
addisons
sepsis
euvolaemic:
hypothyroidism
SIADH (eg. pneumonia, lung Ca)
hypervolaemic:
cardiac failure (increased hydrostatic pressure)
liver and kidney failure (reduced oncotic pressure)
causes of:
hypercalcaemia
normal or high PTH
- hyperparathyroidism
- benign familial hypercalciuria
low PTH
- boney mets
- PTHrH releaseing lung Ca
- myeloma
- exogenous vitamin D excess
polyuria differentials
- UTI
- prostate enlargement
- detrusor instability
- medications (loops, thiazides, SGLT2i)
- 3rd space mobilisation (NOCTURIA)
- polydipsia
- DI
- DM
- hypercalcaemia
causes of cranial DI
V- Sheehans
I- meningitis, TB
T- head injury
A- hypopysitis, langerhans histocytosis, sarcoid
M-
I- transphenoidal surgery
N- craniopharyngioma
C- pit stalk insufficiency syndrome
causes of nephrogenic DI
congenital
post AKI (acute)
drugs eg. lithium
hypercalcaemia
hypokalaemia
carbohydrate counting and units
1 unit per 10g carbs
1 unit brings down by ~3mmol/L
inject insulin ~15mins before eating
long and short term complications of hypoglycaemia
short:
loss of consciousness
- seizures
- arrhythmias
- sudden cardiac arrest
long:
- reduced cognition
- lack of awareness of symptoms and increased risk of hypo
osteoporosis RFs
post menopausal
immobility
hypothalamic hypogonadism- AN
not able to weight bare
low testosterone
cushings
causes of primary hyperaldosteronism
bilateral idiopathic adrenal hyperplasia: the cause of around 60-70% of cases
adrenal adenoma: 20-30% of cases
unilateral hyperplasia
familial hyperaldosteronism
adrenal carcinoma
features of hyperaldosteronism
high aldosterone: renin ratio (high ald which is suppressing renin)
hypokalaemia - muscle weakness
metabolic alkalosis
management of DKA in adults
Main principles of management:
fluid replacement
most patients with DKA are deplete around 5-8 litres
isotonic saline is used initially, even if the patient is severely acidotic
insulin
an intravenous infusion should be started at 0.1 unit/kg/hour
once blood glucose is < 14 mmol/l an infusion of 10% dextrose should be started at 125 mls/hr in addition to the 0.9% sodium chloride regime
correction of electrolyte disturbance
serum potassium is often high on admission despite total body potassium being low
this often falls quickly following treatment with insulin resulting in hypokalaemia
potassium may therefore need to be added to the replacement fluids
if the rate of potassium infusion is greater than 20 mmol/hour then cardiac monitoring may be required
long-acting insulin should be continued, short-acting insulin should be stopped
mechanism of action of spironolactone
mineralocorticoid receptor antagonist
used in hyperaldosteronism
drugs that cause neutrophilia
steroids
lithium
Signs of thyroid eye disease
Failure of up and out movement due to tethering of the medial rectus by inflammation (+TSHrAb specific - cross reactivity)
Periorbital oedema
proptosis/ exopthalmous (sclera seen inferiorly)
conjunctival inject
symptoms:
gritty eyes
double vision
pain
loss of vision if inflammation compresses the optic nerve
what can cause a falsly low HbA1c reading?
Sickle-cell anaemia
GP6D deficiency
Hereditary spherocytosis
Haemodialysis
what can cause a falsly high HbA1c reading
Vitamin B12/folic acid deficiency
Iron-deficiency anaemia
Splenectomy
management of steroid induced hyperglycaemia
if glucose >12mmol/L on more than one occasion in 24 hrs start a once daily sulfonyurea eg gliclazide
treatment for diabetic neuropathy
amitriptyline, duloxetine, pregabalin or gabapentin as the first-line treatment for neuropathic pain
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