endo Flashcards
what medication is to be prescribed prior to an adrenalectomy to stabilise BP and K+ levels?
spironolactone - it is a potassium sparing diuretic so will retain the K+ ions in body
diagnosis from raised renin and raised aldosterone?
secondary hyperaldosteronism - renin secreting tumour is present
presentations of Cushing’s syndrome?
abdominal striae, moon face, buffalo hump
and weight loss in extremities
presentations of Addison’s disease?
hyperpigmentation, central weight loss, hypotension
Loss of which feedback system results in an increase of cortisol in the body?
Hypothalamo-pituitary-adrenal axis
what test determines cranial or nephrogenic diabetes insipidus?
water deprivation test with desmopressin
what is the diagnostic criteria for DM?
- Fasting plasma glucose >7mmol/L
- HbA1c of ≥48mmol/mol
- Symptoms
- random plasma glucose >11mmol/L
hyperkalaemia ECG?
- absent P waves
- prolonged PR
- tall T waves
- wide QRS complex
- bradycardia
what is carcinoid syndrome?
a paraneoplastic syndrome where a rare cancerous tumour (carcinoid tumour) secretes 5-HT
- classical triad of cardiac involvement, diarrhoea and flushing
how can Crohn’s disease lead to secondary adrenal insufficiency?
- long term medication for Crohn’s is corticosteroids, which causes suppression/atrophy of adrenal glands
- withdrawal from these meds can cause secondary adrenal insufficiency
which cancers can cause SIADH?
ACTH secreting; small cell carcinoma, prostate, pancreatic, thymus cancer and lymphomas
list some symptoms of hyperkalaemia
- muscle weakness/cramping
- paraesthesia
- anxiety
- palpitations
- abdo pain
- diarrhoea
- dyspnoea
- hyperreflexia
list 6 complications of acromegaly
- T2DM
- obstructive sleep apnoea
- cardiomyopathy
- hypertension
- stroke
- colorectal cancer
first line investigation for acromegaly?
serum IGF-1, would be raised (IGF-1 increases with GH secretion)
first line treatment for acromegaly?
transsphenoidal resection of pituitary adenoma
name 3 classes of drugs used to treat acromegaly and an example of each
- SST analogues, e.g. octreotide
- GH antagonist, e.g. pegvisomant
- dopamine antagonists, e.g. cabergoline
give 4 differential diagnoses of polyuria and polydipsia
DM, DI, SIADH, primary polydipsia
what is the main cause of primary hyperparathyroidism?
solitary adenoma (80% cases)
list the signs and symptoms of primary hyperparathyroidism
- bones: bone pain/fractures
- stones: renal/biliary stones
- groans: constipation, abdo pain, PUD, pancreatitis
- psychic moans: depression
- thrones: polyuria, polydipsia
definitive treatment for primary hyperparathyroidism?
total parathyroidectomy
first line investigation for Cushing’s disease?
overnight dexamethasone suppression test
most common cause of Cushing’s syndrome?
exogenous, e.g. excess corticosteroid use
main feature of a U&E for hyperaldosteronism?
hyperkalaemia
first line investigation of hyperaldosteronism?
aldosterone renin ratio
How do you distinguish between primary and secondary hyperaldosteronism?
High ratio = primary / low ratio = secondary
main finding on ECG in hypercalcaemia?
Shortening of the QT interval
2 signs for hypocalcaemia
- Chvostek’s: tap over facial nerve causes spasm of facial muscles
- Trousseau’s: inflate bp cuff to 20mmHg above systolic for 5 mins and hand should form a claw
where does the superior thyroid artery arise from?
external carotid artery
cause of hypercalcaemia via malignancy?
excessive secretion of parathyroid hormone released peptide (PTHrP)
list 4 functions of PTH
- increases Ca2+ absorption in gut
- increases Ca2+ reabsorbed in kidney -> less is excreted in urine
- decreases phosphate reabsorption in kidney, increasing amount excreted
- stimulates osteoclasts to reabsorb bone mineral, increasing bone remodelling and turnover
Give 5 generalised symptoms of a pituitary adenoma.
- N/V,
- headaches,
- infertility,
- changes in periods,
- fatigue,
- depression/anxiety,
- vision problems
list 5 signs or symptoms would you see with increased TSH
heat intolerance, sweating, weight gain, palpitations, anxiety, fatigue, irregular periods
what symptoms would you see in carcinoid syndrome?
cutaneous flushing, recurrent diarrhoea, abdo cramps, asthma-like wheezing
what would you see on physical exam in carcinoid syndrome?
- erythema
- pellagra skin lesions
- wheezing
- hepatosplenomegaly from metastases
- pulmonary systolic and diastolic heart murmur
What drug is commonly used to reduce thyroid hormone production?
carbimazole
outline the physiology of how carbimazole exerts its effects.
Blocks thyroid peroxidase from coupling and iodinating the tyrosine residues on thyroglobulin, leading to decreased thyroid hormone production
Provide 4 signs and/or symptoms of a patient experiencing DKA
nausea, fruity breath, abdo pain, hypotension, tachycardia, reduced consciousness
what is a phaeochromocytoma?
rare tumour of the adrenal medulla
which cells is a phaeochromocytoma usually composed of?
chromaffin cells
give 4 symptoms of a phaeochromocytoma
diaphoresis, hypertension, tachycardia/palpitations, pallor, diabetes
which test confirms a diagnosis of Addison’s disease?
synacthen test - ACTH stimulation
which drug used in treatment of asthma may cause hypokalaemia?
salbutamol
persistent hypertension, chronic headache, muscle cramps and fatigue: suspect what?
primary hyperaldosteronism
treatment for DKA?
IV fluids before insulin therapy
what is the gold standard diagnosis for phaeochromocytoma?
elevated plasma free metanephrine
how does insulin act on cells?
reduces glycogenolysis
secondline treatment for T2DM?
metformin + sulfonylurea
diagnostic criteria for DKA?
- Blood Glucose >11 mmol/L
- Plasma Ketones >3 mmol/L
- Blood pH <7.3
- Bicarbonate <15 mmol/L
What is the most common subtype of Thyroid carcinoma?
papillary
blood test results for Graves disease?
low TSH, high T3/4
Where in the adrenal gland are catecholamines produced and secreted?
adrenal medulla
Conn’s syndrome is what type of mineralocorticoid excess syndrome?
primary aldosteronism
What class of immunoglobulin is involved in Graves disease?
IgG
What test would be most useful to confirm your diagnosis of carcinoid syndrome?
chromagranin-A + octreoscan
what would the blood test results show for primary hypothyroidism?
high TSH, low T4
what U&E blood test would you expect to find in SIADH?
hyponatraemia
what would the blood test results show for secondary hypothyroidism?
low TSH, low T3/4
what does glucagon stimulate?
lipolysis
where does fertilization occur?
ampulla
The first few cellular differentiation of a zygote is called cleavage. When does cleavage occur?
day 2-3
name 5 tests required for diagnosis of DKA and the results required
Blood glucose >= 11.1mmol/L
Plasma ketones >= 3 mmol/L
Ketonuria > 2+ on dipstick
Venous pH <7.35
HCO3- <15.0mmol/L
name 4 risk factors for DKA
- stopped insulin
- infection
- pancreatitis
- undiagnosed DMT1
- surgery
name 3 complications of DKA
- coma
- cerebral oedema
- pneumonia
What aspect on a urine dipstick would indicate that the patient has diabetes insipidus (DI) instead of diabetes mellitus?
glucose negative
The patient is diagnosed with diabetes insipidus, what test would be run to differentiate cranial and nephrogenic DI and what result would indicate it is cranial?
IM desmopressin test. Urine becomes concentrated in cranial.
what class of medication would you give to cranial DI and name an example of this
ADH analogue; desmopressin
In patients with nephrogenic DI you give them NSAIDs, what is the physiology behind this?
NSAIDs Inhibit prostaglandins which stops their inhibition of ADH action
give some examples of counselling advice you should give to someone undergoing a PSA test
- Raised PSA doesn’t indicate prostate cancer, at his age it will likely be raised
- would a negative result reassure him?
- if he does have cancer likely watch and wait
What is the difference between benign prostatic hyperplasia and benign prostatic enlargement?
Hyperplasia is a histological diagnosis and enlargement is a clinical diagnosis
What type of hypersensitivity reaction is Grave’s disease?
type 2
What causes the hyperparathyroidism in grave’s disease?
Pathological stimulation of the TSH receptor by circulating IgG autoantibodies
If left untreated what is a possible complication of Grave’s disease?
agranulocytosis
What rare but serious adverse effect of carbimazole will require close monitoring?
thyroid storm
what medication is given to control optical symptoms in Grave’s disease?
high dose glucocorticoids -> immunosuppress
give 2 investigations of Grave’s disease
thyroid ultrasound, iodine thyroid scan
give 3 treatments of Grave’s disease
carbimazole, Radioiodine therapy, Thyroidectomy
Name 2 causes of Acromegaly
Benign Pituitary tumour (growth-hormone secreting), Ectopic Carcinoid tumour (growth-hormone secreting)
What are 3 other signs of Acromegaly?
- Skin darkening
- Coarsening face
- Wide nose
- Big supraorbital ridge
- Interdental separation
- Deep voice
- Large tongue
Name 2 investigations for diagnosing Acromegaly
- serum IGF
- Glucose Tolerance Test (GTT)
- MRI scan of Pituitary Gland
What hormonal changes result in thyroid storm / crisis?
rapid T4 increase
Name 2 things that a thyroid storm can progress to if not treated promptly.
delirium, coma, death, cerebral oedema, pneumonia
Name 2 events which can precipitate thyroid storm.
stress, infection, surgery
Name 3 drugs you would give orally to a patient in thyroid crisis.
- Oral carmbimazole
- Oral propranolol
- Oral potassium iodide
How does hydrocortisone work to reverse a thyroid storm?
inhibits peripheral conversion of T4 to T3
Why would measuring Plasma Growth Hormone levels alone not be diagnostic of Acromegaly?
GH secretion is pulsatile and can be elevated due to stress / pregnancy / puberty
what receptor antibody is specific for Grave’s disease?
TSH-receptor antibody
what is the difference between an endocrine and an exocrine gland?
endo secretes hormones directly into bloodstream, exo secretes into a duct first
give 3 examples of primary adrenal insufficiency
Addisons, surgical removal, trauma
give 3 examples of secondary adrenal insufficiency
steroids, congenital, neoplasm
give 3 appropriate investigations for Cushing’s disease
- 24 hour urinary collection
- random blood cortisol test
- dexamethasone suppression test
explain on a cellular level how hyperglycaemia leads to insulin secretion
- increased glucose uptake by cells
- Glucose metabolism leads to increased levels of ATP within cell
- Increased ATP causes K+ channels to close causing depolarisation of cell membrane
- Ca2+ channels open and Ca2+ enters cell
- Increased Ca2+ in cell causes exocytosis of insulin-containing vesicles
- Insulin released by Pancreatic Beta cells / cells in Islets of Langerhans
give 2 examples of microvascular and macrovascular complications of DM
micro: retinopathy, neuropathy
macro: peripheral artery disease, cerebrovascular disease
what are the thyroid autoantibodies found in graves disease?
thyroglobulin and anti-thyroid peroxidase antibodies
What medication is used to treat hypothyroidism?
synthetic levothyroxine
what is the gold standard test for finding the CAUSE of primary hyper-aldosteronism?
adrenal vein sampling
what is Conn’s disease in simple terms?
primary hyperaldosteronism
briefly describe the renin-angiotensin-aldosterone system
- renin is released by juxtaglomerular cells in response to decrease in renal perfusion
- renin increases ang 1 formation from angiotensinogen
- ang 1 turns to ang 2 via ACE released from lungs
- ang 2 stimulates ADH secretion from posterior pituitary
name and give an example of 1 drug used for the medical treatment of adrenal hyperplasia
aldosterone antagonists e.g. spironolactone
give 3 common presenting symptoms of hyperaldosteronism
HTN, weakness/fatigue, headaches, cramps, polyuria/dipsia
what is the triad of ketoacidosis?
hyperglycaemia, ketonaemia, acidaemia
pathophysiology of ketoacidosis?
- in absence of insulin
- peripheral uptake of glucose by tissues is reduced
- ketones are produced in absence of glucose and accumulate
blood results for secondary hyperparathyroidism?
high PTH, hypocalcaemia, hyperphosphataemia
what kind of HTN does addisons cause?
hypotension
name 5 complications of long term steorid use
DM, Immunosuppression, Osteoporosis, Proximal muscle weakness, Thinned skin
describe relapsing remitting MS
most common, acute attacks followed by periods of remission
describe primary progressive MS
progressive deterioration from onset
describe secondary progressive MS
relapsing remitting deterioration progressing onto straight onset
describe progressive relapsing MS
progressive deterioration from onset with relapsing
give 5 signs or symptoms of Cushing’s
- mood change
- acne
- buffalo hump
- osteoporosis
- moon face
- thinning of skin
give 2 diagnostic tests of Cushing’s
24hr urine cortisol, overnight dexamethasone suppression test, ACTH plasma levels, pituitary MRI
give 2 complications that may arise from Cushing’s
bone fractures, depression/mood changes, hypertension, infections, diabetes
what would the blood results be for primary hyperparathyroidism?
high PTH, high calcium, low phosphate
what is the karyotype for Turner’s syndrome?
45, XO
what is first line step in addisonian crisis?
STAT dose of 100mg hydrocortisone
what can Conn’s syndrome cause?
hypokalaemia
why does polyuria occur in diabetes mellitus?
increased conc of glucose in the tubule urine means it cannot all be reabsorbed in the kidneys so more water is drawn in and a larger volume of urine is produced
