endocrine diseases Flashcards
Risk factors, pathology, signs, complications, diagnosis, and treatment for all endocrine conditions on the phase 2a list.
diabetes mellitus
metabolic disorder of chronic hyperglycaemia due to insulin resistance or deficiency
T1DM risk factors
hypothyroidism
Addison’s
Coeliac disease
T2DM risk factors
HLA DR3 mutation
family history
lifestyle
secondary diabetes due to
haemochromatosis, cancer, CF
signs of diabetes
polyuria polydipsia tiredness blurred vision weight loss (due to water loss and gluconeogenesis)
signs of diabetic ketoacidosis
chronic hyperglycaemia
raised plasma ketones
metabolic acidosis (low bicarbonate)
kussmaal breathing
How does diabetic ketoacidosis occur?
reduced insulin –> reduced fat breakdown and formation of glycerol and free fatty acids –> impair glucose uptake and are transported to liver –> oxidised to ketone bodies
complications of diabetes mellitus
microvascular disease: stroke and CVD retinopathy due to leakage and occlusion of blood vessels (protein, fat, and glial cells grow down blood vessels) neuropathy nephropathy peripheral vascular disease foot ulceration
fasting glucose diabetes mellitus diagnosis
> 7 mmol/L
random glucose diabetes mellitus diagnosis
> 11.1 mmol/L
HbA1c diabetes mellitus diagnosis
> 6.5%
test urine to diagnose diabetes
moderate to large urinary ketones
T1DM treatment
insulin
T2DM treatment
lifestyle modifications
statins and bp lowering drugs
metformin
sulfonylureas (e.g. gliclazide)
how does metformin work?
it reduces gluconeogenesis and increases glucose sensitivity
treatment of DKA
rehydration
insulin
electrolyte replacement
treat underlying cause
risk factors for hyperthyroidism
hyperiodinism too much synthetic thyroxine Graves' disease thyroiditis amiodarone
primary hyperthyroidism
high T3 and T4
low TSH
secondary hyperthyroidism
high T3 and T4
high TSH
signs of hyperthyroidism
prefers cold weather, bad tempered
symptoms of hyperthyroidism
pretibial myxoedema (rare) sweaty diarrhoea oligomenorrhoea weight loss tremor palpitations visual problems
complications of hyperthyroidism
osteoporosis
thyroid storm
treatment of hyperthyroidism
radioiodine therapy thyroid surgery beta-blockers carbimazole thionamide
risk factors for hypothyroidism
low dietary iodine
Hashimoto’s thyroiditis (autoimmune)
surgery
post-partum thyroiditis (affects 1 in 20 women)
other autoimmune conditions: T1DM, Addison’s, vitiligo, alopecia
primary hypothyroidism
high TSH
low T3 and T4
secondary hypothyroidism
pituitary dysfunction
low T3, T4, and TSH
tertiary hypothyroidism
hypothalamus problem
low T3, T4, and TSH
signs of hypothyroidism
prefers warm weather
goitre
symptoms of hypothyroidism
depressed slow tired thin hair croaky voice heavy periods constipation dry skin puffy face
diagnosis of hyperthyroidism
thyroid function test - raised T4, low TSH
diagnosis of hypothyroidism
thyroid function test - low T4, TSH varies throughout the day (higher when dark)
check for thyroid autoantibodies
treatment of primary hypothyroidism
levothyroxine
thyroxine dose for patient with hypothyroidism
1.6mg per kg of body weight
autoimmune hypothyroidism
inflammatory infiltrate replaces follicles
thyroglobulin and thyroid peroxidase antibodies
thyroid cell destruction is mediated by CD8 T cells
risk factors for Grave’s disease
genetic environmental female smoking having another autoimmune disorder
pathology of Grave’s disease
thyroid stimulating immunoglobulin causes excess production of thyroid hormones
signs of Grave’s disease
poor heat tolerance sleeping problems tachycardia acropachy (finger clubbing) proptosis (eye bulging)
symptoms of Grave’s disease
pretibial myxoedema eye bulging unintentional weight loss muscle weakness goitre oligomenorrhoea hand tremor
complications of Grave’s disease
Grave’s ophthalmopathy
treatment of Grave’s disease
radioiodine uptake therapy
thyroid surgery
beta blockers
carbimazole
action of carbimazole
acts on thyroid peroxidase enzyme
risk factors for Hashimoto’s thyroiditis
female
over 60
HLA-DR5
Hashimoto’s thyroiditis
gradual autoimmune destruction of the thyroid gland
goitre due to lymphocyte and plasma cell infiltration
signs of Hashimoto’s thyroiditis
panic disorder
heavy periods
enlarged and lobulated thyroid
symptoms of Hashimoto’s thyroiditis
goitre weight gain feeling tired constipation depression
complications of Hashimoto’s thyroiditis
thyroid lymphoma (non-Hodgkin)
diagnosis of Hashimoto’s thyroiditis
antithyroid peroxidase antibodies (TPOAb)
anti-thyroglobulin antibodies
treatment of Hashimoto’s thyroiditis
levothyroxine
cause of Cushing’s disease
pituitary adenoma
or ectopic tumour producing ACTH
pathology of Cushing’s disease
adrenal gland produces more cortisol due to excess ACTH
signs of Cushing’s disease
hypertension weak muscles acne fragile skin which heals poorly central obesity osteoporosis
symptoms of Cushing’s disease
central obesity with thin arms and legs hump women have more hair irregular menstruation chronic tiredness proximal myopathy
symptoms of Cushing’s disease
central obesity with thin arms and legs hump women have more hair irregular menstruation chronic tiredness proximal myopathy purple abdominal striae
diagnosis of Cushing’s disease and Cushing’s syndrome
Dexamethasone suppression test
- check medication
- check levels of cortisol after taking dexamethasone
- if cortisol remains high, do a blood test for ACTH - ACTH will be high if patient has Cushing’s
treatment of Cushing’s disease and Cushing’s syndrome
treat underlying cause
risk factors for prolactinoma
female
prolactinoma pathology
lactotroph cell pituitary tumour
or may be tumour in pituitary fossa that interrupts stalk and stops dopamine
signs of prolactinoma
visual field defect CSF leak infertility galactorrhoea amenorrhoea low testosterone
symptoms of prolactinoma
headache
changes in menstrual cycle
low libido
diagnosis of prolactinoma
blood test - check prolactin levels
medical imaging
drug history
treatment of prolactinoma
dopamine agonists - cause tumour to shrink
microadenoma responds to small doses of cabergoline
mean age at diagnosis for acromegaly
44
pathology of acromegaly
pituitary tumour releasing growth hormone –> IGF-1 released from liver –> growth of hands and tongue
signs of acromegaly
arthralgias (joint pain) acral enlargement (hands) maxillofacial changes excessive sweating hypogonadal symptoms macroglossa prognathism frontal bossing
symptoms of acromegaly
increased size of extremities snoring deep voice decreased libido headache arthralgia
complications of acromegaly
osteoarthritis T2DM sleep apnoea hypertension CAD stroke headache life expectancy decreased by 10 years
diagnosis of acromegaly
glucose tolerance test
can exclude by finding low serum GH
MRI scan
IGF-1
treatment of acromegaly
surgery
somatostatin analogues (octreotide)
pegvisomant growth hormone analogue
radiotherapy (takes about 5 years - eventually turns tumour to scar tissue)
pathology of Conn’s syndrome
primary hyperaldosteronism resulting in low renin
often due to adrenal gland enlargement or an adrenal gland adenoma
signs of Conn’s syndrome
hypertension muscular weakness excessive micturition poor vision signs of hypokalaemia (e.g. muscle problems)
symptoms of Conn’s syndrome
headaches
muscle spasms
tingling sensations
complications of Conn’s syndrome
cardiovascular disease
diagnosis of Conn’s syndrome
U&E - low renin, high aldosterone
adrenal vein sampling
medical imaging
treatment of Conn’s syndrome
surgery
aldosterone antagonists (spironolactone)
low salt diet
dexamethasone (for familial disease)
risk factors for Addison’s disease
primary adrenal insufficiency past history of TB post-partum bleed cancer steroids
pathology of Addison’s disease
autoimmune adrenal destruction
decrease in adrenal function causes increase in ACTH
signs of Addison’s disease
skin colour changes
decrease in aldosterone –> decrease in Na+ and increase in K+
alopecia
symptoms of Addison’s disease
lean tired anorexia weakness fever confusion depression
complications of Addison’s disease
adrenal crisis and death under physiological stress
diagnosis of Addison’s disease
imaging
ACTH stimulation test - cortisol remains low
primary Addison’s disease diagnosis
high ACTH
high renin
secondary Addison’s disease diagnosis
low ACTH
treatment of Addison’s disease
hydrocortisone for cortisol
fludrocortisone for mineralocorticoids
why does Addison’s disease cause pigmented skin?
ACTH acts on melanocortin receptor on adrenal glands and on skin
risk factors for hyperkalaemia
low aldosterone WNK1 and WNK4 mutations low sodium delivery to DCT low serum potassium level kidney injury Addison's disease drugs - ACEi, spironolactone
pathology of hyperkalaemia
excessive intake, decreased secretion, or a shift of potassium from the intracellular to the extracellular space
signs of hyperkalaemia on ECG
tall tented T waves
small P waves
wide QRS complex
ventricular fibrillation
symptoms of hyperkalaemia
frank muscle paralysis dyspnoea palpitations chest pain nausea vomiting paresthesias
complications of hyperkalaemia
cardiac arrest
diagnosis of hyperkalaemia
ECG
urine potassium, sodium, and osmolality
FBC
metabolic profile
treatment of hyperkalaemia
polystyrene-sulfonate resin
furosemide
haemodialysis
insulin with glucose
hypokalaemia risk factors
poverty
poor diet
causes of hypokalaemia
diuretics vomiting and diarrhoea pyloric stenosis rectal villous adenoma intestinal fistula Cushing's syndrome steroids ACTH Conn's syndrome alkalosis renal tubular failure
signs of hypokalaemia
muscle weakness hypotonia hyporeflexia cramps tetany palpitations light-headedness constipation
complications of hypokalaemia
cardiac arrest following bradycardia
diagnosis of hypokalaemia
bloods - U&Es
ECG
treatment of hypokalaemia
tentative supplementation of potassium
risk factors for syndrome of inappropriate secretion of ADH (SIADH)
cancer CNS disorders chest disease hypothyroidism drugs
which cancers can cause SIADH?
lung small cell
pancreatic cancer
thymus cancer
lymphoma
which CNS disorders can cause SIADH?
meningoencephalitis abscess stroke subarachnoid haemorrhage subdural haemorrhage trauma neurosurgery Guillain-Barré vasculitis SLE
which chest diseases can cause SIADH?
TB
pneumonia
abscess
aspergillosis
which drugs can cause SIADH?
opiates
psychotropics
SSRIs
cytotoxics
signs of SIADH
anorexia
lethargy
symptoms of SIADH
chronic pain
diagnosis of SIADH
U&Es
diagnosis of exclusion
treatment of SIADH
treat the cause
restrict fluid (only 1L/day) - measure input and output
salt ± loop diuretic (furosemide)
demeclocycline if fluid restriction not working
vasopressin receptor antagonists (tolvaptan)
risk factors for diabetes insipidus
disease of kidney or pituitary
pathology of diabetes insipidus
the passage of large volumes of dilute urine (more than 3L/day) due to impaired water resorption by the kidney
cranial diabetes insipidus
reduced ADH secretion from the posterior pituitary
nephrogrenic diabetes insipidus
impaired response of the kidney to ADH
symptoms of diabetes insipidus
polyuria polydipsia dehydration symptoms of hypernatraemia no glucosuria
diagnosis of diabetes insipidus
water deprivation test - osmolarity won’t rise
more than 3L urine a day
differentiating cranial from nephrogenic diabetes insipidus
osmolarity will increase following desmopressin in cranial, but not in nephrogenic
treatment of cranial diabetes insipidus
desmopressin
treatment of nephrogenic diabetes insipidus
treat the cause
try bendroflumethiazide if it persists
NSAIDs
why do NSAIDs lower urine volume and plasma Na+?
they inhibit prostaglandin synthase (prostaglandins locally inhibit the action of ADH)
pathology of hypercalcaemia of malignancy
PTH-RP released from cancer cells, or breakdown of bone
symptoms fo hypercalcaemia of malignancy
bone pain abdominal pain kidney stones nausea constipation polyuria lethargy depression
bones, stones, groans, and moans
complications of hyperacalcaemia of malignancy
QT gets shorter
treatment of hypercalcaemia of malignancy
bisphosphonates
calcitonin
fluids
what can cause a false reading of hypercalcaemia?
tourniquet on for too long
sample old and haemolysed
hypocalcaemia risk factors
low serum albumin
low magnesium
vitamin D deficiency
signs of hypocalcaemia
SPASMODIC Spasms (Chvostek's sign on face and Trousseau's sign on hand) Paraesthesia Anxiety Seizures Muscle tone increase Orientation difficulties Dermatitis Impetigo herpetiformis Cataracts
complications of hypocalcaemia
QT gets longer
treatment of hypocalcaemia
calcium gluconate
cardiac monitoring
pathology of primary hyperparathyroidism
autonomous PTH secretion
parathyroid gland adenoma
complications of hyperparathyroidism
pepper pot skull
diagnosis of hyperparathyroidism
DEXA scan for osteopenia/osteoporotic risk
high calcium with tertiary
treatment of primary and secondary hyperparathyroidism
surgery to remove tumour
treatment of tertiary hyperparathyroidism
surgery to remove parathyroid gland
pathology of secondary hyperparathyroidism
increased PTH secretion to compensate for prolonged hypocalcaemia
pathology of tertiary hyperparathyroidism
development of parathyroid hyperplasia after long-standing hyperparathyroidism
loss of negative feedback
cause of hypoparathyroidism
autoimmune
signs of hypoparathyroidism
hypocalcaemia
Trousseau’s sign
Chvostek’s sign
symptoms of hypoparathyroidism
tetany
diagnosis of hypoparathyroidism
serum calcium (low)
serum albumin
PTH
treatment of hypoparathyroidism
calcium gluconate
calcitriol
treatment of serotonin producing neuroendocrine tumour
octreotide (somatostatin analogue)
risk factors for thyroid cancer
radiation exposure at young age (causes DNA damage)
enlarged thyroid
family history
female
signs of thyroid cancer
neck pain and voice change (due to compression of recurrent laryngeal nerve) symptoms of hyper/hypothyroidism thyroid nodules (worrying if patient is under 20 as benign tumour unlikely)
diagnosis of thyroid cancer
USS
fine needle aspiration
measure TSH
treatment of thyroid cancer
radiation therapy (radioactive iodine) chemotherapy thyroid hormone therapy targeted therapy surgical removal followed by hormone replacement therapy