DUMS Endo Flashcards
What is homeostasis
Physiological regulation of the body to keep processes in a stable equilibrium
What is autocrine signalling
A response produced by a cell which acts on itself
The retropharyngeal space lies between which two fascial layers
the pretracheal and prevertebral fascia layers
Which fascial layer encloses all the other neck fascial compartments
Investing (deep) fascia
Which fascial layer is the most superficial out of all the deep fascial layers
Investing fascia
Which of the pituitary secretions is mainly controlled by inhibition and by why chemical
Prolactin is mainly controlled by the inhibitory effect of dopamine
Asides from being inhibited by dopamine, how else is prolactin secretion controlled
Secretion caused by TRH
what is the difference between a pituitary macroadenoma and a microadenoma
MACROadenoma = >1cm MICROadenoma = ≤ 1cm
Which structure can a non-functioning macroadenoma compress and where does this structure lie
Optic chiasm
which is superior to the pituitary gland
Which cranial nerves are at risk of being compressed by a pituitary tumour
3, 4, 6
How can a non-functioning pituitary adenoma cause the likes of HYPO -adrenalism, -gonadism, -thyroidism
Can grow and wipe out cells that usually produce hormone – ACTH cells wiped out = hypoadrenalism etc
How can a non-functioning pituitary adenoma cause diabetes insipidus
Grow and compress the posterior pituitary thus decreasing/ stopping the production of ADH
Which visual field defect can a pituitary growth cause
Bitemporal Hemianopia
What is the most common type of pituitary tumour
Prolactinoma
What gender-specific symptoms will a prolactinoma present with
Males -> impotence
Females -> cycle irregular
Which investigation should be carried out if you suspect a pituitary tumour…
MRI pituitary fossa
What is the treatment for a prolactinoma and how does it work
Dopamine agonist (Cabergoline) Inhibits prolactin release
How is acromegaly diagnosed
IGF1
Glucose Tolerance Test (75g Oral)
-> diagnostic if GH unchanged or > 1ug/L (normal <0.4)
What GI symptoms can Acromegaly present with
Colon Polyps
Which MSK hand condition can Acromegaly put you at higher risk of
Carpal tunnel syndrome
What is the 1st line treatment for Acromegaly and what should be done after this
Pituitary surgery/ Radiotherapy to pituitary fossa
Repeat GTT
Is surgery is unsatisfactory for Acromegaly, what drugs can be used and how do they work
Dopamine agonist (dopamine inhibits GnRH) Somatostatin analogue (somatostatin inhibits GH) Pegvisomant (GH receptor antagonist)
What do parafollicular C cells secrete
Calcitonin
What is calcitonin involved in
Minor role in calcium regulation
What is the major regulatory step in the HPT axis
TSH release from the anterior pituitary regulated by TRH
Which two carrier molecules are responsible for transporting thyroxine around the body
Thyroxine-binding-globulin
Transthyretin
What is a dietary cause of hypothyroidism
Lack of iodine in diet
Antibodies for Hashimoto’s thyroiditis
Thyroid peroxidase antibodies (Anti-TPO)
What is the management of hypothyroidism
Levothyroxine 50-100 MICROgrams
How often should you check TSH levels for someone being treated for hypothyroidism
TSH every 2 months after any dose change
4 weeks after first starting
Once stable 12-18 months
What kind of menstrual irregularities can hyperthyroidism cause
Less frequent periods
What is De Quervain’s thyroid pathology and what is it caused by
Sub acute thyroiditis – viral trigger
A smooth symmetrical goitre and symptoms of hyperthyroidism should make you think of what
Grave’s disease
An asymmetrical goitre and symptoms of hyperthyroidism should make you think of what
Multi-Nodular goitre
Toxic Nodule - thyroid adenoma
What drugs can be given to treat thyrotoxicosis and the symptoms of thyrotoxicosis
Beta Blockers –> for symptomatic relief
Carbimazole/ PTU –> to lower thyroxine
Which nerve is at risk from thyroid surgery and how would an injury to this structure present
Recurrent laryngeal nerve
Hoarse voice
What are the three treatments you could consider in acute hypercalcaemia
Fluids- rehydrate with 0.9% saline 4-6L in 24hours
Loop diuretics once rehydrated- avoid thiazides
Bisphosphonates
Which biochemical marker will be high in Paget’s
ALP
What will PTH levels be like in a bone malignancy
Very low
physiological response to high Ca
What is the difference between rickets and osteomalacia
Rickets is in kids
Osteomalacia is in adults
What is the normal range of blood sugar
4-6mmol/L
What is the normal range of HbA1c for a diabetic
48-58mmol/l
What are 3 different ways to diagnose T2DM
Random blood sugar test > 11mmol/l
Fasting blood sugar > 7 on 2 occasions
OGTT > 11mmol/l after 2 hours
What is a rare but serious side effect of Metformin
Lactic Acidosis
After what age are TZD’s not recommended and why
Over 65’s due to increase in fracture risk
How are GLP-1 agonist administered
Sub-cutaneous injection
Which malignancy can GLP-1 agonists cause
Pancreatic cancer
What is the most common GLP-1 agonist
Exenatide (synthetic Exendin-4)
Which GLP-1 agonist is DPP-IV resistant
Liraglutide
What is the most commonly used DPP-IV inhibitor
Sitagliptin
What level of ketonaemia is diagnostic of DKA
> 3mmol/L
What blood glucose level is diagnostic of DKA (with relevant symptoms/ history)
> 11mmol/l
What bicarbonate and pH levels diagnose DKA
Bicarbonate < 15mmol/L
pH < 7.3
What kind of breathing is specific to DKA
Kussmaul’s breathing
What is Kussmaul’s breathing trying to achieve in DKA
Attempt to blow off CO2 to lower pH of the blood
Attempt to compensate for the metabolic acidosis
Which condition is blood glucose typically higher in, DKA or HHS
HHS
When checking blood sugar, where should the lancet be used
Lancet against the side of the distal portion of a finger.
Don’t use the lancet on the finger pad.
What is the major regulator of aldosterone production
RAAS
When is RAAS activated
A decrease in blood pressure
How does angiotensin 2 increase blood pressure
direct (vasoconstriction) and indirect (aldosterone)
What are 4 possible causes of primary adrenal insufficiency
Addison’s
Congential Adrenal Hyperplasia
Adrenal Tb
Malignancy
What are 3 possible causes of secondary adrenal insufficiency
Lack of ACTH stimulation
Iatrogenic (excess exogenous steroid)
Pituitary/hypothalamic disorders
How is Addison’s diagnosed
SHORT synACTHen test
Measure cortisol 30 mins after ACTH administration. Should be > 550 mmol/l
What is the management of Addison’s
Hydrocortisone (Corisol mimic)
Fludrocortisone (Aldosterone mimic)
In someone with Addison’s, where will they have areas of hyperpigmentation
Classically mucosal membranes, extensor surfaces and palmar creases
Why do you not give fludrocortisone in secondary adrenal insufficiency
Because the adrenal gland is functioning fine and the RAAS system will be regulating the release of Aldosterone just fine so no replacement needed
What is a common way in which an Addisonian crisis can occur
Steroid therapy stopped suddenly
Adrenal glands have ‘gone to sleep’
Why is myopathy a feature of Cushing’s syndrome
Glucocorticoids alter protein metabolism
Reduced protein synthesis
What are the 2 categories of causes of Cushing’s
ACTH dependent
ACTH independent
Name 3 ACTH dependent causes of Cushing’s
Pituitary adenoma -> most common
Ectopic ACTH production
Ectopic CRH
Name 3 ACTH independent causes of Cushing’s
Adrenal adenoma
Adrenal carcinoma
Nodular hyperplasia
What is the difference between Cushing’s Syndrome and Cushing’s Disease
Syndrome = Excess Cortisol due to any cause Disease = Excess Cortisol due to pituitary pathology
How is Cushing’s diagnosed
Overnight dexamethasone suppression test - screening
Short dexamethasone suppression test
What is the commonest cause of 2ndary hypertension
Conn’s syndrome
What does renin do
Converts angiotensinogen into Ang I
What happens to angiotensin I in the RAAS
Angiotensin I converted to Ang II by ACE
Where is ACE found
Pulmonary vascular endothelium
What is the commonest cause of Conn’s syndrome
Bilateral adrenal hyperplasia
How is Conn’s diagnosed
Aldosterone: Renin ratio
Saline suppression test
(Failure to suppress aldosterone by 50% with 2L of saline is diagnostic)
What is done after Conn’s is diagnosed, via a saline suppression test, to work out the treatment plan
Adrenal CT to demonstrate adenoma
What is the treatment of Conn’s syndrome
Spironolactone/ eplerenone if bilateral hyperplasia
Laparoscopic Adrenalectomy if unilateral adenoma
What is the treatment of PCOS
Antioestrogens (Clomifene citrate or Tamoxifen) Aromatase inhibitors (Letrozole)
What is the normal range of HbA1c for a non-diabetic
below 41mmol/L
