zerotofinals questions

Question 1

A 19 year old man presents with polyuria, polydipsia, vomiting and exhaustion.

On examination he has reduced skin turgor, dry mouth and sunken eyes, and a sweet acetone smell to his breath.

His blood pressure is 94/67, heart rate 106, respiratory rate 19, temperature 36.7C and oxygen saturation of 99% on room air.

While waiting for laboratory blood tests and an ABG to come back, the emergency department nurse checks his capillary blood glucose on a bedside device. The result simply says “high”, and is unrecordable.

What is the most appropriate initial management whilst awaiting further results?

Answer 1

IV fluids
This patient is most likely in DKA. The local DKA protocol should be followed in this patient.

The most important initial management for patients with DKA is rehydration by IV fluids. They are more likely to die of dehydration rather than hyperglycaemia. Rehydration with IV fluids will help bring down the blood glucose even before insulin is started, and will help correct the acidosis. It is important to closely monitor potassium as this can drop very quickly in patients with DKA.

Question 2

What electrolyte disturbance would make you consider a diagnosis of SIADH?

Answer 2

Hyponatraemia
ADH is anti-diuretic hormone. It causes reabsorption of water from the collecting ducts in the kidneys back into the blood. This means, it takes more water out of the urine and puts it back into the blood. This is one mechanism the body uses to keep us from excreting too much water in the urine and becoming dehydrated.

In SIADH (syndrome of inappropriate ADH), there is excessive ADH. Therefore, excessive water is reabsorbed into the blood. This excess of water in the blood dilutes sodium, causing a hyponatraemia.

Question 3

What is the underlying pathology in Cushing’s disease?

Answer 3

Pituitary adenoma
Cushing’s syndrome is used to refer to the clinical picture (signs and symptoms) that reflect prolonged abnormal elevation of cortisol
Cushing’s disease is used to refer to the specific condition where a pituitary adenoma (tumour) secretes excessive ACTH, causing Cushing’s syndrome

Question 4

A 57 year old lifelong smoker presents with a 3 month history of worsening unintentional 3 stone weight loss, haemoptysis and fatigue. On examination she has central obesity, abdominal striae, muscle wasting and a “buffalo hump”.

Based on the limited information provided, what is the most likely diagnosis?

Answer 4

Small cell lung cancer
This patient has symptoms of lung cancer, and Cushing’s syndrome. The type of cancer that produces ectopic ACTH, and therefore a Cushing’s syndrome as a “paraneoplastic syndrome” is Small Cell Lung Cancer?

Question 5

A 44 year old lady presents complaining of chronic fatigue and general tiredness. She has also noticed her hair and skin becoming more dry and is worried she might be loosing her hair.

On examination her thyroid gland is barely palpable

Her blood tests reveal a TSH of 13 (normal range 0.5 – 4.0 mIU/L) and free T4 of 1.1 (normal range 4.5 to 11.2 mcg/dL).

What is her most likely diagnosis?

Answer 5

Hashimoto’s thyroiditis is the most common cause of hypothyroidism in the developed world. It would be appropriate to commence her on levothyroxine.

Causes of Hypothyroidism

Hashimoto’s thyroititis
Autoimmune inflammation of the thyroid
Goitre followed by atrophy of the thyroid gland
Most common cause of hypothyroidism in developed world
Iodine Deficiency
Most common cause in the developing world
Anti-hyperthyroid treatments
Medications (e.g. lithium, amiodarone)
Central causes
Causing low TSH
Hypopituitary conditions

Question 6

The conversion of protein into glucose

Answer 6

gluconeogenesis

Question 7

the conversion of glycogen into glucose

Answer 7

glycogenolysis

Question 8

specifically inhibited by sitagliptin

Answer 8

DDP-4

Question 9

directly stimulates muscle cells to use glucose as fuel

Answer 9

insulin

Question 10

directly stimulates secretion by beta cells in the islets

Answer 10

incretins

Question 11

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?

Answer 11

de quervian’s thyroiditis

Question 12

What hormone, secreted from the anterior pituitary stimulates the adrenal gland to produce cortisol?

Answer 12

ACTH:
The Adrenal Axis

Hypothalamus releases corticotrophin releasing hormone (CRH)
CRH stimulates anterior pituitary to release adrenocorticotrophic hormone (ACTH)
ACTH stimulates adrenal cortex to release cortisol
Cortisol is a “glucocorticoid” steroid hormone that is always present, and increases in response to stress
Cortisol works in several ways:
Inhibits the immune system
Inhibits bone formation
Raises blood glucose
Increases metabolism
Increases alertness

Question 13

A 41 year old man is diagnosed with acromegaly secondary to a large pituitary adenoma.

What visual field defect would you expect he might have?

Answer 13

Bitemporal hemianopia:
Pressure on the optic chiasm will lead to a stereotypical “bitemporal hemianopia” visual field defect (loss of vision on the outer half of both eyes)

Question 14

Which of the following is NOT an effect of cortisol?

Answer 14

Stimulates the immune system

Question 15

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?

Answer 15

adrenal adenoma

Question 16

in what disease could you find pretibial myxoedema

Answer 16

Graves Disease: Pretibial Myxoedema is a dermatological condition where there are deposits of mucin under the skin on the anterior aspect of the leg (pre-tibial area). This gives a discoloured, waxy, oedematous appearance to the skin over this area. It is specific to Grave’s disease and a reaction to the TSH receptor antibodies.

Question 17

A 56 year old lady presents with anxiety, goitre and bilateral exopthalmos.

What is the most likely diagnosis based on this limited information?

Answer 17

Unique Grave’s Disease Features (resulting from the TSH receptor antibodies)

Diffuse Goitre (without nodules)
Graves Eye Disease
Bilateral Exopthalmos
Pretibial Myxoedema

Question 18

A 45 year old, normally fit and well lady presents with polyuria and polydipsia. On examination she appears dehydrated. Her blood sugar and other blood tests are normal.

What is the most appropriate next step in investigating this patient?

Answer 18

Fluid deprivation and ADH stimulation test

This patient may have diabetes incipidus. A fluid deprivation and ADH stimulation test would be the most appropriate investigation to confirm the diagnosis and distinguish between a central or a nephrogenic cause.

Question 19

Which one of the following medications is considered a somatostatin analogue?

Answer 19

Ocreotide

Question 20

What condition is associated with TSH receptor antibodies?

Answer 20

Grave’s disease
TSH receptor antibodies are specific to Graves disease. They are antibodies that mimic TSH and stimulate the TSH receptors, leading to hyperthyroidism.

Question 21

is high in Hashimotos thyroiditis

Answer 21

TSH

Question 22

Inhibit the secretion of glucagon

Answer 22

GLP-1

Question 23

stimulates pituitary gland

Answer 23

TRH

Question 24

Produced by the posterior pituitary

Answer 24

ADH

Question 25

specifically targets adrenal glands

Answer 25

ACTH

Question 26

produced by adrenal glands

Answer 26

cortisol

Question 27

the active form of thyroid hormone

Answer 27

T3

Question 28

has a half life of 7 days

Answer 28

T4

Question 29

indirectly reduce secretion of insulin

Answer 29

DPP-4

Question 30

A 45 year old with known primary adrenal failure presents to her GP with a 3 day history of a dry cough, sore throat, muscles aches and a blocked nose.

Examination reveals evidence of the symptoms above, however she is apyrexial and her chest is clear.

What is the most appropriate management?

Answer 30

Double her maintainence steroid dose
This patient is known to have primary adrenal failure, so she will be on long term steroid replacement. She is presenting with symptoms of a viral upper respiratory tract infection. She should be like anyone else with regard to her viral infection (i.e. advice regarding the self limiting nature of the illness, plenty of fluids and rest) but it is essential in patients on steroid replacement to double the dose of steroids until well again to mimic the normal physiological response to the stressful event.

Osteltamivir is used to treat flu, however it is usually only used when the patient presents within 2 days of the onset of illness.

Addisons Treatment

Replacement steroids titrated to clinical sign, symptoms and electrolytes
Hydrocortisone is used to replace cortisol (the glucocorticoid)
Fludrocortisone is used to replace aldosterone (the mineralocorticoid) where required
Patients are given a steroid card and emergency ID tag to alert emergency services if needed
Doses should not be missed (they are essential to life)
Double the dose of steroids during an illness until recovered

Question 31

Which of the following would you expect to find in a patient with Conn’s syndrome?

Answer 31

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.

Question 32

What is Conn’s Syndrome?

Answer 32

An adrenal adenoma secreting excessive aldosterone

Question 33

A 57 year old man presents with fluctuating symptoms of intense anxiety, sweating, palpitations and headache. These can last half and hour and happen several times a day. They have been getting worse over the last 2 months.

What would be the most appropriate investigation given the suspected diagnosis?

Answer 33

Plasma metanephrines

symptoms of a pheochromocytoma. This can be checked for using plasma metanephrines or 24 hour urine catecholamines (both breakdown products of adrenalin).

It would be appropriate to screen this patient for other conditions as well, such as performing a thorough physical examination, checking thyroid function, electrolytes and an ECG.

If the results are positive for metanephrines or catecholamines, or negative but the diagnosis is still highly suspected, it would be appropriate to obtain a CT scan to look for evidence of an adrenal tumour.

Question 34

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.

On examination she has a GCS of 12 and is confused. 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?

Answer 34

IV hydrocortisone 100mg

addisonian crisis

Question 35

Which of the following medication are generally considered safe when used as monotherapy in patients at risk of hypoglycaemia (e.g. lorry drivers)?

Answer 35

Diabetic medication causing hypoglycaemia: Sulfonylureas (i.e. gliclazide) and insulin.

Sitagliptin (DPP-4 inhibitor) and exenatide (GLP-1 mimetic) can cause hypoglycaemia when taken with other hypoglycaemics, but are not considered to cause hypoglycaemia on their own.

Question 36

What type of cells produce adrenalin in the adrenal glands?

Answer 36

Adrenalin is produced by the “chromaffin cells” of the adrenal glands
A pheochromocytoma is a tumour of the chromaffin cells, that secretes unregulated, excessive adrenalin
Adrenalin is a “catecholamine” hormone
25% are familial, associated with Multiple Endocrine Neoplasia Type 2 (MEN 2)
10% rule:
Bilateral
Cancerous
Outside adrenal gland

Question 37

What type of cells secrete parathyroid hormone?

Answer 37

There are four parathyroid glands, situated in four corners of the thyroid gland
The parathyroid glands (specifically the chief cells in the glands) produce parathyroid hormone in response to hypocalcaemia (low blood calcium)
Parathyroid hormone acts to raise blood calcium level by:
Increasing osteoclast activity in bones (reabsorbing calcium from bones)
Increasing calcium absorption from the gut
Increasing calcium absorption from the kidneys
Increasing vitamin D activity (that then increases calcium absorption from the gut)

Question 38

An 87 year old man is post op after a total hip replacement following a fractured neck of femur. He is found to have hyponatraemia that is stable around 120 mmol/l.

This is causing postural hypotension, muscle cramps and occasional mild confusion.

He is euvolaemic, has a urinary sodium concentration of 75 mmol/l, and has normal thyroid function, chest xray and short synacthen tests.

Fluid restriction achieves a slight rise in serum sodium to 125 mmol/l.

What is the next most appropriate option for treating the cause of his hyponatraemia.

Answer 38

Tolvaptan

This patient has SIADH post operatively. This is treated with fluid restriction initially. In the past, demeclocycline (a tetracycline antibiotic with the side effect of blocking ADH) was used, however this has been surpassed by vaptans (ADH receptor blockers such as tolvaptan). This are normally used under the guidance of an experienced clinician (e.g. an endocrinologist) and it is important to monitor the sodium concentration during the process.

A rise in sodium that is too fast gives a risk of central pontine myelinolysis (a neurological condition).

Question 39

Fasting glucose 6.4 mmol/l and oral glucose tolerance test 7.3 mmol/l at 2 hours

Answer 39

impaired fasting glucose

Question 40

random blood glucose 9.6 mmol/l

Answer 40

not enough info to make diagnosis

Question 41

Fasting glucose 7.0 mmol/l and oral glucose tolerance test 11.2 mmol/l at 2 hours

Answer 41

T2DM

Question 42

HbA1c 39 mmol/mol

Answer 42

normal

Question 43

Fasting glucose 5.9 mmol/l and oral glucose tolerance test 7.9 mmol/l at 2 hours

Answer 43

impaired glucose tolerance

Question 44

What is the most appropriate investigation to confirm the diagnosis in a patient who presents with symptoms of Cushing’s syndrome?

Answer 44

Dexamethasone suppression test

Question 45

Which one of the following medication acts as an aldosterone antagonist?

Answer 45

Eplerenone and spironolactone are aldosterone antagonists. They are commonly used in severe heart failure, particularly following an MI. They are also used hyperaldosteronism.

Question 46

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?

Answer 46

Reduce levothyroxine dose to 125mcg once daily

Levothyroxine treatment in hypothyroidism is normally titrated with a target TSH in the lower half of the normal range (i.e. 0.4 – 2.5).

This patient’s TSH is slightly low. This suggests that her pituitary is being over-suppressed by the dose of levothyroxine she is taking (i.e. she is taking too much).

An appropriate response to this value would be to slightly decrease the dose of levothyroxine and check her TSH again in a month’s time.

There is nothing to gain from measuring T3 or T4 levels in this scenario.

Question 47

What is the cutoff for a HbA1C level indicating a diagnosis of Type 2 Diabetes?

Answer 47

> 48 mmol/mol

Question 48

Which of the following has the greatest inhibitory affect on growth hormone?

Answer 48

Dopamine is an inhibitor of growth hormone, however somatostatin has a larger inhibitory effect than dopamine.

Both somatostatin analogues (e.g. ocreotide) and dopamine agonists (e.g. bromocriptine) are used to control symptoms of acromegaly whilst awaiting definitive treatment (i.e. surgery).

Question 49

What type of cells, found in the pancreas, secrete glucagon?

Answer 49

alpha

Question 50

When treating a patient who is in DKA with a fixed rate insulin infusion, what is the most important thing to add to the fluid infusion?

Answer 50

Potassium chloride
Patients in DKA have low total body potassium. Insulin drives potassium out of the blood and into cells (along with glucose). It is therefore very easy for patients being treated for DKA to develop a very low serum potassium, which is potentially fatal. Potassium should be monitored very closely and additional potassium added to the infusion to prevent this happening.