Endo - to review Flashcards
All amine hormones are derived from tyrosine except one which is derived from tryptophan, it is:
Dopamine Epinephrine Thyroxine Norepinephrine Melatonin
Melatonin
Melatonin is the only hormone derived from tryptophan, rest are from tyrosine
Which of the following would you expect to find in a patient with Conn’s syndrome?
Hypokalaemia Hyponatraemia Hyperkalaemia Hypermagnesaemia Hypernatraemia
Hypokalaemia
Aldosterone causes sodium reabsorption and potassium and hydrogen excretion at the kidneys. Therefore, you expect to find hypokalaemia, hypertension (due to excessive sodium – serum sodium is usually the higher end of normal) and alkalosis.
What type of cells secrete parathyroid hormone?
Chief Cells Leydig Cells Beta Cells Chromaffin Cells Parafollicular Cells
Chief Cells
Chief cells produce parathyroid hormone in response to hypocalcaemia (low blood calcium)
Parafollicular cells (C cells) produce calcitonin in response to high calcium
40 yr old woman presents with weight loss, irritability and excessive sweating and palpitation and is found to have an undetectable serum TSH level and a serum free thyroxine level of 40pmol/l (normal range 10-25 pmol/l). Which medication would provide rapid relief to her symptoms?
Propranolol Carbimazole Mitotane Levothyroxine Propylthiouracil
Propranolol
According to NICE guidelines, which one of the following is the correct indication to stop metformin therapy in the presence of renal impairment?
eGFR <15 mL/minute/1.73 m2
eGFR <30 mL/minute/1.73 m2
eGFR <45 mL/minute/1.73 m2
eGFR <60 mL/minute/1.73 m2
eGFR <30 mL/minute/1.73 m2
review @ <45
A 32 year old otherwise fit and well female patient is bought into hospital by her roommate, who found it difficult to wake her up in the morning. Over the last few hours she has become increasingly more confused and drowsy, and was feeling faint. Her blood pressure is 81/45, heart rate 68, respiratory rate 12, temperature 35.9C and oxygen saturations of 98% on room air. Her blood tests reveal the following abnormalities: Glucose 3.2, Sodium 129 Potassium, 5.4, CRP 3.4. Other than correcting her hypoglycaemia and administering IV fluids, what is the most appropriate immediate management?
IV amiodarone 150mg IM glucagon 1mg IM adrenalin 500 mcg IV tazocin 4.5g IV hydrocortisone 100mg
IV hydrocortisone 100mg
*addisonian insufficiency
A 35 year old male has been newly diagnosed with bipolar affective disorder after admission to a psychiatric hospital with acute mania. He has been started on lithium. What is a side effect of lithium on thyroid function?
Primary hyperthyroidism
Secondary hyperthyroidism
Primary hypothyroidism
Secondary hypothyroidism
Primary hypothyroidism
Lithium is one of the causes of Primary hypothyroidism
A decrease in circulating cortisol levels would result in which of the following physiological responses:
Enhanced gluconeogenesis in the liver. Hypotension Decreased ACTH secretion from the anterior pituitary Elevated fatty acid levels in the plasma Suppression the immune system
Hypotension
All the other options are responses to cortisol secretion. Decreased plasma cortisol would therefore not stimulate these processes and hypotension occurs due to a loss of the permissive effects of cortisol on norepinephrine binding to α1 receptors.
Life threatening hypotension is associated with Addison’s Disease where there is “adrenal crisis” and a loss of both glucocorticoid and mineralocorticoid release, although in this situation the hypotensive crisis mainly results from the loss of the effect of aldosterone on Na+ retention at the kidney but is augmented by loss of cortisol.
Ms Jones is a 30-year-old female who presents with a 3-month history of 10kg weight loss despite an increased appetite, anxiety, diarrhoea and amenorrhoea. Examination reveals a fine tremor, brisk reflexes and a systolic murmur heard throughout the precordium. A urine pregnancy screen was negative. What is the most likely finding on examining the pulse?
Pulsus paradoxus Collapsing pulse Low volume pulse Irregularly irregular pulse Pulsus alternans
Irregularly irregular pulse
The patient’s symptoms and examination findings are consistent with a diagnosis of hyperthyroidism.
The systolic murmur is likely to be a functional murmur due to a hyperdynamic circulation caused by the hyperthyroidism.
Hyperthyroidism can cause atrial fibrillation which would cause an irregularly irregular pulse.
Which of the following pharmacological agents used for diabetes puts you at risk of hypoglycaemia?
Liraglutide Pioglitazone Canagliflozin Exenatide Gliclazide
Gliclazide
Sulfonylureas (–zide) stimulate insulin release from the pancreas so they put you at risk of hypoz
How does cortisol protect against hypoglycaemia?
It increases the levels of blood glucose It strongly inhibits insulin It strongly inhibits glucagon It causes glycogenolysis It has a permissive effect on glucagon
It has a permissive effect on glucagon
Loss of cortisol means animals cannot deal with stress, particularly in terms of protecting us against hypoglycaemia.
→ Because cortisol has a permissive effect on glucagon
Cortisol does inhibit insulin but not to the extent that it prevents hypoglycaemias!
Which of the following pharmacological agents used for diabetes puts you at risk of diabetic ketoacidosis?
Metformin Pioglitazone Canagliflozin Exenatide Gliclazide
Canagliflozin
SGLT-2 inhibitor (gliflozins) — associated with diabetic ketoacidosis as a rare side effect
A 65 year old male presents to the GP with a triad of episodic headache,palpitations and sweating. This tends to fluctuate throughout the day and he hasn’t noticed any weight change. On examination, his observations were: BP 172/108, HR 130, RR 22 and SpO2 99%. The patient remembers his dad having similar problems but can’t remember the name of it. Given the probable diagnosis, what would be the most appropriate investigation?
Short synacthen test CT scan MRI scan Chromaffin-seeking isotope scan 24 hour urine catecholamines
24 hour urine catecholamines
Headache, palpitations, sweating, hypertension, tachycardia…
All indicative of phaeochromacytoma
24 hour urine catecholamines or urine free metanephrines is the test of choice!
Which symptom below is NOT typical of hypoglycaemia?
Headache Itch Poor concentration Sweating Irritability
Itch
A 22 year old woman presents with heart palpitations, weight loss and excessive sweating. On examination you note evidence of bilateral exophthalmos. She discloses she is in a long term relationship and actively trying to get pregnant. Which treatment plan is most appropriate?
Carbimazole Propylthiouracil Radioactive iodine Thyroidectomy Lobectomy
Propylthiouracil
A 34 year old man presents with tachycardia, fever, and neck soreness. He has been feeling run down with muscle aches and lethargy for the past 5 days. He is normally fit and well.On examination he has tenderness over his thyroid gland.Blood tests reveal a suppressed (low) TSH and a raised T3 and T4. What is the most likely diagnosis?
Solitary Toxic Thyroid Nodule Toxic Multinodular Goitre Graves Disease Hashimoto's Thyroiditis De Quervain's Thyroiditis
De Quervain’s Thyroiditis
De Quervain’s Thyroiditis
A viral infection presenting with fever, neck pain and tenderness, dysphagia and features of hyperthyroidism.
Hyperthyroid phase followed by hypothyroid phase as TSH falls due to negative feedback
Self-limiting condition and supportive treatment with NSAIDs and beta blockers is usually all that is necessary
Which one of the following side effects are associated with long-term metformin use?
Magnesium deficiency
Pyridoxine deficiency
B12 deficiency
Thiamine deficiency
B12 deficiency
A 54 year old previously healthy man presents with tiredness, worsening over the past 2 months. On examination you note abdominal striae, central obesity, a round, pale face and wasted proximal muscles. You arrange a dexamethasone suppression test. The patient has no suppression of cortisol with 1mg of dexamethasone, and 8mg of dexamethasone is unable to suppress his cortisol but does suppress ACTH levels. What is the most likely diagnosis?
Cushings Disease Chronic exogenous steriods Adrenal adenoma Small Cell Lung Cancer HIV encephalitis
Adrenal adenoma
- sign of ectopic ACTH secretion independent of endocrine secretion
Low Dose Dexamethasone Suppression Test (1mg dexamethasone)
A normal response is for cortisol to be suppressed (the feedback mechanism is working normally in response to the high blood steroids level
– The hypothalamus responds by reducing the CRH output
– The pituitary response by reducing the ACTH output
An abnormal response is seen in Cushing’s syndrome.
– The hypothalamus and pituitary are used to a higher level of cortisol, meaning that this low additional dose doesn’t cause a reaction
High Dose Dexamethasone Suppression Test (8mg dexamethasone)
- In Cushing’s Disease (pituitary adenoma) this is enough to suppress cortisol
- In Cushing’s syndrome (i.e. adrenal adenoma), cortisol is not suppressed, but ACTH is
- In ectopic ACTH (e.g. from a small cell lung cancer), neither cortisol or ACTH will be suppressed
Which of the following pharmacological agents used for diabetes puts you at risk of bladder cancer?
Metformin Pioglitazone Canagliflozin Exenatide Gliclazide
Pioglitazone (TZD)
A 54-year-old male who was previously well presents to his GP with ongoing headaches for the past few months. He also complains of difficulty sleeping at night due to breathlessness. He reports struggling to fit into his clothes recently and his wedding ring no longer fits. His blood pressure in clinic is 162/83 mmHg. What is the single most-appropriate test that would confirm the likely diagnosis?
Insulin-like growth factor 1 Urinary catecholamines Dexamethasone suppression test Short acting synacthen test Aldosterone-renin ratio
The most likely diagnosis here is acromegaly, which can be confirmed by elevated levels of insulin-like growth factor 1 (IGF-1).
Acromegaly is a manifestation of excessive growth hormone, which is produced by the anterior pituitary gland. The most common cause for excessive production of growth hormone is a pituitary adenoma, a benign tumour of the pituitary gland. Growth hormone stimulates the liver to produce IGF-1.
Gigantism, e.g., clothes not fitting anymore, enlarged fingers etc.
Commonest cause of XS GH
Pituitary Adenoma (benign)
GH effect. on IGF-1
Growth hormone stimulates the liver to produce IGF-1.
What type of cells secrete calcitonin?
Parafollicular Cells
A 45 year old man attended a routine medical and his BP was 162/100mmHg. ABPM for 24 hours showed 152/98mmHg and he was started on an ACE inhibitor. 6 months later his blood pressure is still high despite adding a calcium channel blocker and he is now complaining of leg cramps and headaches. His blood tests show hypokalameia, low renin and high aldosterone. A CT scan of his abdomen shows bilaterally enlarged adrenal glands. What will be the first step of treatment for this patient?
Bilateral adrenalectomy Spironolactone Bendroflumethiazide Amiloride Mitotane
Spironolactone
Hyperprolactinaemia is not a result of taking which drug?
B2 agonist Neuroleptics (e.g. chlorpromazine) Oral contraceptive pill Oestrogen containing medication Anti-emetics (e.g. metoclopramide)
B2 agonist
A 64 year old woman with hypothyroidisim presents for her routine annual review. Her blood test one week ago reveals a TSH of 0.2 mIU/l (normal range 0.4 to 4.0). She is currently on 150 mcg once daily of levothyroxine. What is the most appropriate next step in management?
Check T4 level
Reduce levothyroxine dose to 125mcg once daily
Re-check TSH in 1 month
Check T3 level
Increase levothyroxine dose to 175mcg once daily
Reduce levothyroxine dose to 125mcg once daily
An 80 year old lady who is keen to stay healthy and well comes to see you in clinic. She has been having daily episodes of sweating and palpitations and been feeling hungry. She has had type 2 diabetes for 30 years and is on Metformin 1g bd and Glipizide 5mg bd. Her renal function has deteriorated but her GFR is 50 with a creatinine of 88. Her HbA1c is 51mmol/mol. During one of the episodes she checked her blood glucose and found that it was 3.0mmol/l. What action should be taken initially with regard to her management?
Stop metformin Stop Glipizide Check blood glucose more regularly Repeat HbA1c Request a holter monitor
Stop Glipizide
Glipizide should be stopped as she is having daily hypos and sulphonylureas can cause hypoglycaemia. This is the biggest risk to her safety and her blood glucose levels appear to be reasonably well controlled and the aim of treating her diabetes is to keep her well and safe.
