Endocrine Flashcards
thyroid hormones
- highest
- lowest
highest - night
lowest - morning
neck lump that moves up on swallowing
thyroid goitre
neck lump that moves up on swallowing and sticking out tongue
thyroglossal cyst
branchial cyst presentation
large neck swelling on side
teenage years
cystic hygroma presentation
congenital
large neck swelling
orphan annie nuclei
papillary thyroid cancer
psomomma bodies
papillary thyroid cancer
spread of papillary thyroid cancer
lymphatic
spread of papillary follicular cancer
haematogenous
medullary thyroid ca association
MEN IIa or IIb
what is medullary thyroid ca
ca of parafollicular cells
Mx of thyroid ca
total thyroidectomy + radio-iodine
antibody in graves disease
tsh receptor antibody
Mx graves for rapid symptom relief
propanolol
Mx graves
carbimazole alone
or
carbimazole + thyroxine (block and replace) for 12-18m then withraw
- radio-iodine
drug causing thyrotoxicosis
amiodarone
antibody in hashimotos thyroiditis
anti-TPO antibody
subacute de-quervains thyroiditis
post-viral with painful goitre
progression of subacute de-quervains thyroiditis
starts with hyperthyroid – euthyroid – hypothyroid
drugs causing hypothyroidism
lithium
amiodarone
Monitoring primary hypothyroidism
TSH
Monitoring secondary hypothyroidism
T4
hormones releases by the anterior pituitary
ACTH TSH GH LH FSH Prolactin
hormones released by the posterior pituitary
Oxytocin
ADH
cranial diabetes insipidus
failure of the posterior pituitary to release ADH
causes of cranial diabetes insipidus
idiopathic
neoplasm
post-surgery
trauma
wolfram’s syndrome
‘DIDMOAD’
Diabetes Insipidus
Diabetes Mellitus
Optic Atrophy
Deafness
nephrogenic diabetes insipidus
failure of the kidneys to respond to ADH
causes of nephrogenic diabetes insipidus
genetic
electrolyte abnormalities -
hypercalcaemia, hypokalaemia
drugs - lithium
drug that causes nephrogenic diabetes insipidus
lithium
presentation diabetes insipidus
polyuria (large volumes of dilute urine)
polydipsia
Ix diabetes insipidus
plasma osmolality - high
urine osmolality - low
water deprivation test - will continue to pee ++ volumes
Mx cranial diabetes insipidus
Desmopressin (synthetic analogue of ADH)
what is a ‘non-functioning’ pituitary adenoma
doesn’t secrete active hormones
classification of non-functioning pituitary adenoma
micro-adenoma = <1cm
macro-adenoma = >1cm
presentation of a non-functioning pituitary adenoma
headache worsening visual acuity double vision panhypopituitarism CN palsies - III, IV, VI compression bitemporal hemianopia
Ix pituitary adenoma
- pituitary blood profile
2. MRI brain with contrast
Mx pituitary adenoma
observation
surgical removal - transsphenoidal approach, post op XRT
what are the 2 most common hormones to be secreted by a pituitary adenoma
prolactin (prolactinoma)
GH (acromegaly)
presentation of a prolactinoma
Females:
- amenorrhoea
- infertility
- galactorrhoea
- reduced libido
- wt gain
Males:
- erectile dysfunction
- reduced facial hair
- osteoporosis
- galactorrhoea
Mx prolactinoma
Dopamine Agonists:
- bromocriptine
- cabergoline
presentation of acromegaly
coarse facial hair large hands increase in shoe size excessive sweating macroglossia acanthosis nigricans
what genetic condition is associated with acromegaly
MEN I
Ix acromegaly
- IGF-1 levels
- if raised, - Oral Glucose Tolerance Test (OGTT)
- give 75g oral glucose, take level a 0, 30, 0, 90, 120, 150mins
- GH normally inhibited by hyperglycaemia
- if raised, - MRI brain with contrast
Mx acromegaly
- surgical removal (trans-sphenoidal approach)
- somatostatin analogues (inhibit GH) - octreotide
- GH antagonists - pegvisomat
HbA1c level
- normal
- diabetes diagnosis
normal = <41 mmol/L
diabetes = >48 mmol/L
Fasting glucose level
- normal
- diabetes diagnosis
normal = <6 mmol/L
diabetes = >7 mmol/L
2hr OGTT level
- normal
- diabetes diagnosis
normal = < 7.7 mmol/L
diabetes = > 11.1 mmol/L
Random glucose level
- normal
- diabetes diagnosis
normal = < 7.7. mmol/L
diabetes = > 11.1 mmol/L
Ix T1DM
- random blood glucose
- fasting blood glucose
- HbA1c
- 2h OGTT
rapid acting insulins
novorapid
Humalog
short-acting insulins
actrapid
Humulin S
insuman rapid
intermediate acting insulins
Humulin I
Insulatard
Insuman Basal
long acting insulins
Lantus
Levemir
how much insulin in total should someone be taking a day
0.2 - 0.4 units/kg/day
what is a basal bolus regime
basal = 1/2 of the total daily dose of insulin is taken before bed
bolus = 1/2 of the total daily dose of insulin is split over meal times
what is Latent Autoimmune Diabetes of Adulthood
autoimmune diabetes that develops in an older person and is often misdiagnosed as having T2DM
presentation of LADA
young adult 25-40
non-obese
auto ab +ve
non-insulin requiring at diagnosis
Ix T2DM
- random blood glucose
- fasting blood glucose
- HbA1c
- 2h OGTT
metformin - class of drug
biguanide
biguanides - mode of action
improve sensitivity to insulin
benefits of biguanides
no hypo risk
CVS benefits
weight reduction
safe in preg
s/e of biguanides
GI upset
lactic acidosis
glicazide - class of drug
sulphonylurea
sulphonylureas - mode of action
promote insulin release from islet cells
benefits of sulphonylureas
quick reduction in hyperglycaemia
s/e of sulphonylureas
hypo risk
weight gain
no CVS benefits
dapagliflozin - class of drug
SGLT2 inhibitors
SGLT2 inhibitors - mode of action
enhance glucose excretion by the kidney
benefits of SGLT2 inhibitors
no hypo risk
wt loss
CVs benefits
s/e of SGLT2 inhibitors
increased thrush and urine infections
pioglitazone - class of drug
TZDs (PPARy agonists)
TZDs - mode of action
promote glucose uptake
s/e of TZDs
weight gain
fluid retention
increased risk of hip # in elderly
sitagliptin - class of drug
DPP-IV inhibitors (gliptans)
DPP-IV inhibitors - mode of action
act on the incretin pathway
s/e of DPP-IV inhibitors
no CVS benefits
low/mod efficacy
weight neutral
exenatide - class of drug
GLP -1 agonist
GLP-1 agonists - mode of action
acts on the incretin pathway
benefits of GLP -1 agonists
SC injection
wt loss
low hypo risk
s/e of GLP -1 agonist
nausea
pancreatitis
Mx of T2DM
- Lifestyle
- Metformin
- sulphonylurea OR SGLT-2 inhibitor OR DPP inhibitor OR TZD
- one of the above or injectable
what is maturity onset diabetes of the young (MODY)
familial form of early onset T2DM
types of MODY
glucokinase (GCK)
transcription factor
presentation of MODY
strong FHx
renal cysts
GAD -ve
c-peptide +ve
Mx MODY
GCK MODY - no Tx
Transcription Factor MODY - sulphonylurea
what is the hallmark of diabetic nephropathy
proteinuria
Ix of diabetic nephropathy
urinary albumin : creatinine ratio
normal urinary albumin : creatinine ratio
Males < 2.5
Females < 3.5
Mx diabetic nephropathy
ACEi
Mx DKA
- fluid replacement (most are depleted 5-8 litres)
- Insulin infusion (0.1 unit/kg/hr)
- start 5% dextrose infusion when BG <15mmol/L
- correct hypokalaemia (caused by the insulin)
What do you do with a T1DM insulin when they are being treated for DKA
continue their basal insulin, omit bolus insulin
pathogenesis of hyperosmolar hyperglycaemic state (HHS)
hyperglycaemia - osmotic diuresis - loss of Na + K - increase serum osmolality - increase hyperviscosity of blood
Mx HHS
- Fluid Replacement - 0.9% saline IVI over 48h
if ketotic - give insulin
mild hypoglycaemia
- presentation
- Mx
pt conscious, orientated, able to swallow
Mx = 15-20g of quick acting carbohydrate
moderate hypoglycaemia
- presentation
- Mx
pt conscious, able to swallow, disorientated/confused
Mx = 1.5-2 tubes of glucose gel squeezed into mouth between teeth and gums
severe hypoglycaemia
- presentation
- Mx
pt unconscious, fitting, very aggressive or NBM
Mx = IV glucose 150ml 10% or 75ml 20%
causes of primary hyperparathyroidism
solitary adenoma (80%)
hyperplasia of glands
parathyroid Ca
genetic (MEN)
biochem primary hyperparathyroidism
PTH - raised
Ca - raised
Phosphate - low
Alk phos - high
Mx primary hyperparathyroidism
surgical candidate:
parathyroidectomy
non-surgical candidate:
monitoring + bisphosphonates
causes of secondary hyperparathyroidism
this is a physiological response to a low Ca
- chronic renal failure
- vitamin D deficiency
biochem secondary hyperparathyroidism
PTH - raised (appropriately)
Ca - low
cause of tertiary hyperparathyroidism
hyperplastic change to the parathyroid glands -
the parathyroid becomes autonomous after many years of secondary hyperparathyroidism
biochem tertiary hyperparathyroidism
PTH - raised ++ (inappropriately)
Ca - raised
what is familial benign hypocalciuric hypercalcaemia
autosomal dominant defect in Ca sensing
presentation of hypoparathyroidism
related to low Ca
‘SPASMODIC’
Spasms Paraesthesiae Anxious Seizures Muscle tone increase Orientation confused Impetigo Herpetiformis Chvostek's sign
Mx primary hypoparathyroidism
oral Ca supplements + calcitriol
pseudohypoparathyroidism
genetic condition
- failure of target cells to respond to PTH
- high PTH, low Ca
pseudopseudohypoparathyroidism biochem
normal biochem!
secretions of the renal cortex
Glomerulosa - Mineralocorticoids
Fasiculata - Glucocorticoids
Reticularis - Sex Steroids
what stimulates glucorticoid release from the adrenal cortex
ACTH
what stimulates mineralocorticoid release from the adrenal cortex
RAAS system
what stimulates sex steroid release from the adrenal cortex
ACTH
secretions of the renal medulla
catecholamines (adrenaline)
what is addisons disease
primary hypoadrenalism - low cortisol and aldosterone
presentation of addisons disease
ski pigmentation + buccal mucosa ("bronze diabetes") abdo pain fatigue vomiting diarrhoea low BP
Ix for Addisons
short syacthen test
- give 250mcg IM synthetic ACTH
- measure cortisol before and 30mins after
- if cortisol stays low = Addison’s
Mx Addisons
replace the cortisol = hydrocortisone, dexamethasone or prednisolone
replace the aldosterone = fludrocortisone
what is cushings syndrome
the clinical state caused by excess cortisol
causes of cushings syndrome
ACTH dependent causes:
- cushings diease (ACTH secreting pituitary adenoma)
- ectopic ACTH (small cell lung cancer)
ACTH independent causes:
- adrenal tumours
- steroids
screening tests for cushings syndrome
- Overnight dexamethasone suppression test
- give dexa 1mg at night, measure cortisol at 8am - 24h urinary free cortisol
diagnostic test for cushings syndrome
48h dexamethasone suppression
conn’s syndrome
aldosterone producing adenoma - the most common cause of hyperaldosteronism
presentation hyperaldosteronism
- HTN
- hypokalaemia
(main ones to be aware of) - nocturia
- polyuria
- lethargy
- mood disturbance
screening tests for hyperaldosteronism
plasma K (low) aldosterone/renin ratio (raised)
Ix for Conn’s syndrome
- fludrocortisone suppression test
2. high res CT abdo
Mx conn’s syndrome
unilateral tumour - laparoscopic adrenalectomy
bilateral tumour - aldosterone antagonists (spironolactone)
presentation of phaechromocytoma
episodic headache
sweating
tachycardia
+/- high BP
Ix phaeochromocytoma
- bloods - plasma metanephrine levels
2. CT & MRI
Mx phaechromocytoma
1. alpha blockade (doxazosin, prazosin) THEN beta blockade (atenolol, propranolol)
- surgical excision
Mx gynaecomastia
address underlying cause
surgery (cosmetic)
anti-oestrogens (tamoxifen)
causes of hypoglycaemia in a non-diabetic patient
‘EXPLAIN’
EX = Exogenous drugs - alcohol, quinine sulfate, ACEi, aspirin poisoining P = pituitary insuffiency L = liver failure A = Addison's disease I = islet cell tumours e.g. insulinoma N = non=pancreatic neoplasms
most important modifiable risk factor in the development of thyroid eye disease
smoking
T2DM BP target with no end organ damage
< 140/80 mmHg
T2DM BP target with end organ damage
< 130/80 mmHg
Mx of intercurrent illness in a person with Addison’s
double their hydrocortisone dose
triad of renal cell carcinoma
haematuria
abdominal mass
loin pain
Mx renal cell carcinoma
radical nephrectomy