Chemical Pathology

Question 1

Which of the following clinical signs is the best indicator of hypovolaemia?

(a) Tachycardia
(b) Postural hypotension
(c) Reduced skin turgor
(d) Confusion/drowsiness
(e) Low urine Na+ (<20)

Answer 1

The correct answer is (e) Low urine Na+ (<20). All of these signs indicate hypovolaemia however some of them are better than others, and others require some context, or might be affected by confounding factors. However, low urine Na+ is a very accurate indicator that the patient is hypovolaemic as they are retaining salt.

Question 2

Which of the following is a cause of hypovolaemic hyponatraemia?

(a) Hypothyroidism
(b) Cardiac failure
(c) Cirrhosis
(d) Adrenal insufficiency
(e) Diuretics

Answer 2

The correct answer is (e) Diuretics.

Hypothyroidism (a) and adrenal insufficiency (d) are causes of euvolaemic hyponatraemia.

Cardiac failure (b) and cirrhosis (c) are causes of hypervolaemic hyponatraemia.

Question 3

Which of the following is not a cause of SIADH?

(a) Meningitis
(b) Lung cancer
(c) SSRIs
(d) Nephrotic syndrome
(e) Surgery

Answer 3

The correct answer is (d) nephrotic syndrome. Nephrotic syndrome is a cause of hypervolaemic hyponatraemia.

Question 4

In a patient with SIADH what pattern would you expect?

(a) Low plasma osmolality, low urine osmolality.
(b) High plasma osmolality, low urine osmolality.
(c) Low plasma osmolality, high urine osmolality.
(d) High plasma osmolality, high urine osmolality.
(e) Mate I don’t even know what osmolality is.

Answer 4

The correct answer is (c) Low plasma osmolality, high urine osmolality.

Due to SIADH you have excessive water retention, which initially creates volume expansion, which then stimulates atrial natriuretic peptide, which causes water and sodium loss through the kidneys. This is why SIADH causes a euvolaemic hyponatraemia.

Question 5

Which of the following drugs can be used to treat SIADH?

(a) Demeclocycline
(b) Opiates
(c) Carbamazepine
(d) PPIs
(e) TCAs

Answer 5

The correct answer is (a) Demeclocycline.

Demeclocycline reduces responsiveness of collecting tubule cells to ADH, but U&Es must be monitored due to risk of nephrotoxicity.

Another drug that can be used is Tolvaptan which is a V2 receptor antagonist.

Opiates (b), Carbamazepine (c), PPIs (d) and TCAs (e) are all drugs that can cause SIADH.

Question 6

What are the two main stimuli for ADH secretion?

(a) Reduced blood volume and reduced serum osmolality
(b) Reduced blood volume and increased serum osmolality
(c) Increased blood volume and reduced serum osmolality
(d) Increased blood volume and increased serum osmolality

Answer 6

The correct answer is (b) Reduced blood volume and increased serum osmolality.

Question 7

State four causes of hyperkalaemia.

Answer 7

The main causes of hyperkalaemia can be broken down into four groups.

Renal impairment or disease which causes reduced renal excretion of potassium.

Drugs such as ACE inhibitors, ARBs and spironolactone which all act to reduce aldosterone which in turn prevent potassium excretion.

Low aldosterone due to Addison’s disease or type 4 renal tubular acidosis (low renin, low aldesterone)

Potassium release from cells as in rhabdomylosis or acidosis.

Question 8

Which of the following is the correct treatment regimen for hyperkalaemia?

(a) 50ml 10% calcium gluconate, 50 ml 50% dextrose and 10 units of insulin and nebulized salbutamol.
(b) 10ml 10% calcium gluconate, 10 ml 50% dextrose and 10 units of insulin and IV salbutamol.
(c) 50ml 10% calcium gluconate, 10 ml 50% dextrose and 5 units of insulin and nebulized salbutamol.
(d) 10ml 10% calcium gluconate, 50 ml 50% dextrose and 10 units of insulin and nebulized salbutamol.
(e) 10ml 10% calcium gluconate, 50 ml 50% dextrose and 5 units of insulin and IV salbutamol.

Answer 8

The correct answer is (d) 10ml 10% calcium gluconate, 50 ml 50% dextrose and 10 units of insulin and nebulized salbutamol.

Although this is the initial emergency treatment of hyperkalaemia, the full treatment would be to also treat the underlying cause of the hyperkalaemia.

Question 9

Hypokalaemia is a side effect of which of the following drugs?

(a) Furosemide
(b) Spironolactone
(c) Indomethacin
(d) Perindopril
(e) Losartan

Answer 9

The correct answer is (a) Furosemide.

All of the other options cause hyperkalaemia.

Question 10

67 year old man presents with D&V for the past 2 days and was started on bendroflumethiazide for hypertension 2 weeks previously. He has dry mucous membranes and reduced skin turgor. Na+ is 129, K+ 3.5, Urea 8.0 and Creatinine 100.

What is this patient’s status and what should the management be?

(a) Euvolaemic hyponatraemia so treat with hypertonic saline.
(b) Hypervolaemic hyponatraemia so treat with fluid restriction and 0.9% saline.
(c) Hypovolaemic hyponatraemia so treat with hypertonic saline
(d) Hypovolaemic hyponatraemia, but it’s not too low so conservatively watch and wait and encourage the patient to eat and drink
(e) Hypovolaemic hyponatraemia so volume replacement with 0.9% saline.

Answer 10

The correct answer is (e) Hypovolaemic hyponatraemia so volume replacement with 0.9% saline.

This patient has three separate causes of hypovolaemic hyponatraemia in diarrhoea, vomiting and diuretic.

Question 11

55 year old man presents with jaundice and a past history of excessive alcohol intake. He has multiple spider naevi, shifting dullness and splenomegaly. Na+ 122, K+ 3.5, Urea 2.0 and Creatinine 80.

What is this patient’s status and what should the management be?

(a) Euvolaemic hyponatraemia so give normal saline and treat the underlying cause.
(b) Hypovolaemic hyponatraemia so give normal saline and treat the underlying cause.
(c) Hypervolaemic hyponatraemia so treat with fluid restriction, hypertonic saline, and treat the underlying cause.
(d) Hypervolaemic hyponatraemia so give normal saline and treat the underlying cause.
(e) Hypervolaemic hyponatraemia so treat with fluid restriction and treat the underlying cause.

Answer 11

The correct answer is (e) Hypervolaemic hyponatraemia so treat with fluid restriction and treat the underlying cause.

This patient has cirrhosis which is a cause of hypervolaemic hyponatraemia. Cirrhosis causes excess NO production which leads to vasodilation, which causes a drop in blood pressure which in turns stimulates ADH release and subsequent fluid retention and a dilutional hyponatraemia.

Question 12

What occurs first in response to hypoglycaemia?

(a) Suppression of insulin
(b) Release of glucagon
(c) Release of adrenaline
(d) Release of cortisol
(e) Release of insulin

Answer 12

The correct answer is (c) release of adrenaline.

Question 13

C-peptide…

(a) Is the cleavage product of insulin
(b) Is secreted in equimolar amounts to insulin
(c) Has a half life of 2 hours
(d) Interferes with insulin management
(e) All of the above

Answer 13

The correct answer is (b), C-peptide is secreted in equimolar amounts to insulin.

Pro-insulin is cleaved to give C-peptide and insulin so (a) is wrong.

The half life of C-peptide is about 30 minutes so (c) is wrong.

Question 14

20 year old female, BMI 17kg/m2, with some Lanugo hair noted. Finger prick glucose was 3.8mmol/L, and routine bloods were taken. Doctor rung by lab 1 hour later as plasma glucose was 2.6mmol/L.

What is the cause of her low blood sugar?

(a) Undertakes strenuous exercise regularly
(b) Insulinoma
(c) Anorexia with poor liver glycogen stores
(d) Laxative abuse
(e) Zollinger-Ellison syndrome

Answer 14

The correct answer is (c) anorexia with poor liver glycogen stores.

The finger prick glucose being higher is due to a false reading, either because of incidental residual carbohydrates on the hands, or deliberate, as has been noted in some anorexic patients, whereby they rub sugary sweets on their hands to avoid being picked up by the doctor.

Question 15

Same patient, 20 year old female, BMI 17kg/m2, with some Lanugo hair noted. Finger prick glucose was 3.8mmol/L, and routine bloods were taken. Doctor rung by lab 1 hour later as plasma glucose was 2.6mmol/L.

What would the insulin and C-peptide result be if they had been measured?

(a) Low insulin, low C-Peptide
(b) Low insulin, high C-Peptide
(c) High insulin, low C-Peptide
(d) High insulin, high C-Peptide

Answer 15

The correct answer is (a) Low insulin, low C-Peptide.

Question 16

1 day old neonate who is jittery and not feeding. Born by caesarean at 34 weeks gestation. Lab glucose 1.9mmol/L. Glucose improved on feeding, but low blood glucose 4 hours after feed. Beta-hydroxybutyrate measured at time of hypo and was negative.

What’s absence of beta-hydroxybutyrate signify?

(a) Insulin deficiency
(b) Insulinoma
(c) Fatty acid oxidation defect
(d) Starvation and glycogen depletion
(e) Glucagon deficiency

Answer 16

The correct answer is (c) Fatty acid oxidation defect.

Beta-hydroxybutyrate is a ketone body. So free fatty acids would be high in this neonate as there is a defect preventing the conversion to ketones.

Question 17

45 year old lady brought in fitting. Recurrently seen GP in previous months due to weight gain and increased appetite. Husband reports personality change in last few months.

Glucose 1.9 mmol/L, Insulin 35 mu/L and C-peptide 1000pmol/L.

What is the most likely diagnosis?

(a) Cushings syndrome
(b) Addison’s disease
(c) Sulphonylurea excess
(d) Insulinoma
(e) Need more information

Answer 17

The correct answer is (e) Need more information.

Two things can result in this picture, either an insulinoma or sulphonylurea excess. A sulphonylurea screen needs to be done and if that’s negative it would point towards an insulinoma.

Question 18

9 year old boy brought in fitting. Glucose 1.9mmol/L, Insulin 205mu/L, C peptide <33pmol/L.

What is the most likely cause of the low blood glucose in this boy?

(a) Factitious insulin
(b) Epileptic fit
(c) Stress response to exercise
(d) T1DM
(e) Need more information

Answer 18

The correct answer is (a) factitious insulin.

Only exogenous insulin can produce a picture where there is high insulin and low C-peptide. They are produce in equimolar amounts by the body, so this has to be factitious insulin.

Question 19

60 year old cachectic man found unconscious by his daughter. He’s a smoker and his glucose was 1.9mmol/L. Hypoglycaemia persists so given a glucose infusion. Insulin and C-peptide are undetectable, free fatty acids are also undetectable and ketones are negative.

What diagnosis is most likely in this man?

(a) Benign insulinoma
(b) Non-islet cell tumour hypoglycaemia
(c) Malignant insulinoma
(d) Addison’s disease
(e) Panhypopituitarism

Answer 19

The correct answer is (b) Non-islet cell tumour hypoglycaemia.

In non-islet cell tumour hypoglycaemia there is a tumour that causes a paraneoplastic syndrome with secretion of ‘big IGF-2’. Big IGF2 binds to IGF-1 receptor and insulin receptor. This is seen in mesenchymal tumours such as mesothelioma or fibroblastoma, as well as epithelial tumours such as carcinoma.

Levels of glucose, insulin, c-peptide, FFA and Ketones are all suppressed.

Question 20

What is the pathological process in Gilberts Syndrome?

(a) Reduced activity of Aspartate transaminase
(b) Complete deficiency in UDP glucuronyl transferase
(c) Reduction in UDP glucuronyl transferase activity to 30%
(d) Slight obstruction in bile ducts of patients, causing a harmless increase in conjugated bilirubin.
(e) Mutation in albumin that causes bilirubin to be unable to bind to it, causing higher levels of unbound bilirubin in the blood.

Answer 20

The correct answer is (c) Reduction in UDP glucuronyl transferase activity to 30%.

The unconjugated bilirubin is tightly albumin bound and does not enter the urine.

(b) refers to what you’d find in Crigler-Najjar syndrome, an autosomal recessive disease that knocks out the enzyme.

All the rest are bollocks that I made up.

Question 21

Which of the following is the most representative of acute liver function?

(a) Prothrombin time
(b) Albumin
(c) Bilirubin
(d) Alanine amino transferase
(e) Aspartate amino transferase
(f) Alkaline phosphatase
(g) Gamma glutamyl-transpeptidase

Answer 21

The correct answer is (a) Prothrombin.

If you fail to make clotting factors, the prothrombin time rapidly increases, making it an excellent marker for acute liver damage.

Albumin(b) is a good marker of chronic liver function, as the half life is a lot longer

Albumin, clotting factors and bilirubin (c) are all markers of liver function.

The other tests are enzymes which might indicate liver damage but are not truly tests of liver function.

Question 22

Which of the following is caused by B1 deficiency?

(a) Rickets
(b) Scurvy
(c) Pernicious anaemia
(d) Beri-Beri
(e) Pellagra
(f) Neural tube defects.

Answer 22

The correct answer is (d) Beri-Beri.

Rickets (a) is a deficiency in vitamin D.

Scurvy (b) is a deficiency in vitamin C.

Pernicious anaemia (c) is a deficiency in vitamin B12.

Pellagra is a deficiency in vitamin B3

Neural tube defects are caused by deficiency in folate, which is vitamin B9

Question 23

45 year old man presents with jaundice to his GP. He denies excessive alcohol intake, though admits he does enjoy a glass of wine or two. He has no pain anywhere in his abdomen. He has experienced some weight loss over the past two months but reports no fevers. He has no family history of disease, and on abdominal examination he has a palpable gallbladder but no hepatomegaly.

What is the most likely cause for this man’s jaundice?

(a) Haemolysis
(b) Gallstones
(c) Carcinoma of the head of the pancreas
(d) Cirrhosis
(e) Hepatocellular carcinoma

Answer 23

The correct answer is (c) Carcinoma of the head of the pancreas.

Following Courvoisier’s law, in the presence of jaundice, if the gall bladder is palpable the cause is unlikely to be gall stones. Given the painless jaundice and palpable gallbladder against the background of weight loss and lack of fever this is most likely a carcinoma of the head of the pancreas causing an obstructive jaundice.

Question 24

31 year old female seen in GP with general malaise and feeling unwell and “not herself” for about two weeks. She had had a few episodes of vomiting. Routine bloods showed an Hb of 12, an alkaline phosphatase of 165 (normal range 30-130) and a raised alpha feto protein. The GP immediately referred her to the hepatologists on a two week wait.

What is the most likely cause of this patient’s symptoms?

(a) Gallstones
(b) Hepatocellular carcinoma
(c) Metastatic liver cancer
(d) Autoimmune hepatitis
(e) Pregnancy

Answer 24

The correct answer is (e) pregnancy.

Pregnancy can create a host of symptoms that are non-specific and alarming, especially if it’s not known the patient is pregnant. Vomiting is a normal part of first trimester pregnancy, Hb falls as part of normal pregnancy, alk phosphatase can double or triple by the third trimester and alpha feto protein, a marker of hepatocellular carcinoma, can be raised as part of normal pregnancy.

Pregnancy should always be considered a possibility in any woman of childbearing age.

Question 25

A buildup of which part of the haem synthesis pathway causes neurovisceral symptoms of porphyria?

(a) Porophobilinogen
(b) 5-Aminolaevulinic acid
(c) Hydroxymethylbilane
(d) Uroporphyrinogen III
(e) Protoporphyrin IX

Answer 25

The correct answer is (b) 5-Aminolaevulinic acid.

Skin lesions are caused by excess porphyrinogens which are oxidised to porphyrins then in the presence of UV light they become activated and cause the skin lesions.

Question 26

22 year old female just returned from holiday where she’d been drinking heavily. She was complaining of abdominal pain, nausea and vomiting and had become increasingly paranoid. After returning to the UK she had some tonic/clonic seizures, and reported blurred vision and seeing flashing lights.

Serum Na 118 mmol/L, Urine ALA 207 (<3.8), urine PBG 215 (<1.5), hydroxymethylbilane synthase 11 (20-42).

What is the cause of this patient’s symptoms?

(a) Acute intermittent porphyria
(b) Porphyria cutanea tarda
(c) Acute alcohol-induced hepatitis
(d) Illicit drug use
(e) Variegate porphyria

Answer 26

The correct answer is (a) acute intermittent porphyria.

AIP is caused by a deficiency in HMB synthase, which is why ALA and PBG are both raised as they are upstream of HMB synthase. This is not a complete deficiency, usuallly there is around 30-50% of normal function, but certain triggers overly tax the pathway and cause an attack, as detailed in the next question…

Question 27

Which of the following is not a trigger of Acute intermittent porphyria?

(a) Excess carbohydrates
(b) Steroids
(c) Baribiturates
(d) Alcohol
(e) Anticonvulsants

Answer 27

The correct answer is (a) Excess carbohydrates.

In fact, good diet and carbohydrate intake is recommended to prevent attacks of AIP, as carbohydrate levels inhibit the action of ALA synthase. IV carbohydrate is useful in the management of an acute episode of AIP, and reduced calorie intake can be a trigger of AIP.

Question 28

During acute porphyria, the most useful sample to send is?

(a) Blood
(b) CSF
(c) Urine
(d) Stool
(e) Skin Biopsy

Answer 28

The correct answer is (c) urine.

Question 29

Which of the following hormones is not low in pituitary failure?

(a) Cortisol
(b) FSH
(c) Aldosterone
(d) ACTH
(e) TSH

Answer 29

The correct answer is (c) Aldosterone.

Pituitary failure does not equal adrenal failure, Aldosterone production and release is controlled by the renin-angiotensin system which is unaffected by pituitary failure.

Question 30

30 year old female complains of leaking milk from her breasts. On examination she has a bitemporal hemianopia and her prolactin comes back as 30000.

What is the diagnosis?

(a) Cushing’s disease
(b) Acromegaly
(c) Prolactinoma
(d) Non-functioning pituitary adenoma
(e) Normal pregnancy

Answer 30

The correct answer is (c) Prolactinoma.

The rule is it’s always a prolactinoma if prolactin>6000.

Question 31

27 year old with a non-functioning pituitary adenoma is given hydrocortisone, thyroxine, oestrogen and growth hormone replacement.

What else should they be given in addition in the absence of any other symptoms?

(a) Carbimazole
(b) Dexamethasone
(c) Cabergoline
(d) Octreotide
(e) Nothing

Answer 31

The correct answer is (e) nothing.

Cabergoline would be a reasonable answer if they were experiencing symptoms such as galactorrhoea.

Question 32

28 year old woman who has a large pituitary adenoma (2cm). Her basal thyroxine is 6.7 (11-24) and her insulin stress test has the following results:

Each result is at 30 minute intervals starting from 0 minutes.

Glucose: 4.7, 1.8, 2.3, 4.7, 5.2.
GH: 30.5, 40.7, 60.2, 50.5, 44.5
Cortisol: 160, 170, 180, 160, 150
LH: 0.5, 0.7, 0.9
TSH: 0.7, 0.8, 0.9
Prolactin: 1988, 1744, 2311

What would be the appropriate next test to aid diagnosis of this patient?

(a) Low dose dexamethasone suppression test
(b) High dose dexamethasone suppression test
(c) Synacthen test
(d) Glucose tolerance test
(e) TRH stimulation

Answer 32

The correct answer is (d) Glucose tolerance test.

This picture points towards a patient with acromegaly.

Glucose should totally suppress production of growth hormone in normal physiology. Therefore, if growth hormone is still present after a glucose tolerance test it points towards the diagnosis of acromegaly.

Question 33

31 year old female presents with profound tiredness. Acutely unwell for the past few days with some vomiting.

Blood results are: Na 125, K 6.5, U 10, glucose 2.9, Free T4 <5 and TSH of 50.

What diagnosis does this high TSH suggest?

(a) A TSH producing pituitary adenoma
(b) Graves disease
(c) A toxic thyroid nodule
(d) Primary hypothyroidism
(e) de Quervain’s thyroiditis

Answer 33

The correct answer is (d) Primary hypothyroidism.

If (a) were correct you would have a high free T4 as well as a high TSH.

Question 34

32 year old male presents with hypertension, and he is noted to have an adrenal mass. On further investigation his urinary catecholamines are raised.

What urgent drug treatment is required first?

(a) Fluids
(b) Phenoxybenzamine
(c) Propranolol
(d) Calcium gluconate
(e) Hydrocortisone

Answer 34

The correct answer is (b) Phenoxybenzamine.

This patient has a phaeochromocytoma which is an adrenal medullary tumour that secretes adrenaline, and can cause severe hypertension, arrhythmias and death.

Therefore, it is a medical emergency and the use of an alpha blocker such as (b) phenoxybenzamine is urgently important to achieve alpha blockade.

The next step would be to use a beta blocker such as propanolol (c) to achieve beta blockade but this is not the most urgent step.

Question 35

34 year old obese woman with T2DM presents with hypertension and bruising. Na 146, K 2.9, U 4, Glucose 14, Aldosterone <75 (low) and low Renin.

Which dynamic test is most appropriate in this patient?

(a) Insulin tolerance (stress) test
(b) Dexamethasone suppression test
(c) Synacthen test
(d) Glucose tolerance test
(e) TRH stimulation test

Answer 35

The correct answer is (b) Dexamethasone suppression test.

This patient has cushings syndrome, and (b) Dexamethasone suppression test would allow us to differentiate between the causes of cushings.

The most common cause of cushings syndrome is iatrogenic steroids. If the patient is not on steroids, 85% will have pituitary dependent cushings disease, 5% will have ectopic ACTH production and the last 10% will have an adrenal adenoma.

Question 36

An obese 35 year old patient has a 9am cortisol of 650. She is then given 0.5 mg dexamethasone every 6 hours for 48 hours. and her final cortisol is <50.

What is the diagnosis in this patient?

(a) Pituitary dependent cushing’s disease
(b) Adrenal tumour causing cushing’s syndrome
(c) Ectopic ACTH causing cushing’s syndrome
(d) Normal obese person
(e) Cushing’s syndrome of indeterminate cause.

Answer 36

The correct answer is (d) normal obese person.

Question 37

An obese 35 year old patient has a 9am cortisol of 650. She is then given 0.5 mg dexamethasone every 6 hours for 48 hours, and her final cortisol is 500.

What is the diagnosis in this patient?

(a) Pituitary dependent cushing’s disease
(b) Adrenal tumour causing cushing’s syndrome
(c) Ectopic ACTH causing cushing’s syndrome
(d) Normal obese person
(e) Cushing’s syndrome of indeterminate cause.

Answer 37

The correct answer is (e) Cushing’s syndrome of indeterminate cause.

Question 38

An obese 35 year old patient has a 9am cortisol of 650. She is then given 0.5 mg dexamethasone every 6 hours for 48 hours, and her cortisol at 48 hours is 500. She is then given 2mg of dexamethasone every 6 hours for another 48 hours and her final cortisol is 170.

What is the diagnosis in this patient?

(a) Pituitary dependent cushing’s disease
(b) Adrenal tumour causing cushing’s syndrome
(c) Ectopic ACTH causing cushing’s syndrome
(d) Normal obese person
(e) Cushing’s syndrome of indeterminate cause.

Answer 38

The correct answer is (a) Pituitary dependent cushing’s disease.

Question 39

Which of the following commonly presents with depression?

(a) Hyperkalaemia
(b) Hypokalaemia
(c) Hypercalcaemia
(d) Hypocalcaemia
(e) Uraemia

Answer 39

The correct answer is (c) Hypercalcaemia.

Question 40

54 year old man complains of abdominal pains. On further history you elicit he’s been feeling low in mood for the past month. On routine bloods he has a calcium of 2.82 (2.2-2.6) so you order a PTH, which comes back as 2.9 (1.1 - 6.8).

What is the most likely diagnosis in this patient?

(a) Needs more information
(b) Lung cancer secreting ACE
(c) Primary hyperparathyroidism
(d) Secondary hyperparathyroidism
(e) Sarcoidosis

Answer 40

The correct answer is (c) Primary hyperparathyroidism.

If there is hypercalcaemia, the levels of parathyroid hormone will be suppressed in all causes of hypercalcaemia EXCEPT primary hyperparathryoidism where the hypercalcaemia is due to excess production of parathyroid hormone.

This is an inappropriately normal parathyroid hormone.

Question 41

54 year old man complains of abdominal pains. On further history you elicit he’s been feeling low in mood for the past month. On routine bloods he has a calcium of 2.82 (2.2-2.6) so you order a PTH, which comes back as 2.9 (1.1 - 6.8).

An X-ray of this patient’s hands would most likely show?

(a) No changes - normal x-ray
(b) Looser’s zones
(c) Ulnar aspect cystic changes
(d) Radial aspect cystic changes
(e) Changes in random carpal bones

Answer 41

The correct answer is (d) Radial aspect cystic changes.

This is a feature of primary hyperparathyroidism.

Looser’s zones occur in patients with low vitamin D, therefore they’d be seen in hand x-rays of patients with secondary hyperparathyroidism.

Question 42

55 year old afro-caribbean man presents with dyspnoea. Blood tests show a slightly raised calcium and a normal haemoglobin, CXR shows bilateral hilar lymphadenopathy and PTH is suppressed.

What treatment is most important for this patient?

(a) Insulin
(b) Vitamin D
(c) Prednisolone 20mg
(d) Prednisolone 40mg
(e) Thiazide diuretic

Answer 42

The correct answer is (d) Prednisolone 40mg.

This patient has sarcoidosis where macrophages express 1 alpha hydroxylase in the lungs, causing increased activated vitamin D levels. This needs to be suppressed by high dose steroids.

The normal activation of 25 hydroxyvitamin D by 1 alpha hydroxylase to 1, 25 dihydroxyvitamin D in the kidney is completely regulated by parathyroid hormone. In the absence of PTH, this enzyme activation does not occur.

However, the 1 alpha hydroxylase produced in the lung is not confined by the presence of PTH, and instead continuously activates Vitamin D, causing high levels of vitamin D, which in turn causes hypercalcaemia.

Question 43

In which of these scenarios is alkaline phosphatase NOT raised?

(a) Pregnancy
(b) Childhood
(c) Liver cirrhosis
(d) Osteomyelitis
(e) Osteoporosis

Answer 43

The correct answer is (e) Osteoporosis.

ALP is not increased in osteoporosis unless complicated by fractures.

Question 44

Which of the following statements about Creatine Kinase (CK) is false?

(a) CK - MM is in skeletal muscles
(b) CK - MM accounts for almost all of the normal plasma activity
(c) There are two forms of CK-MB (1&2) in cardiac muscles.
(d) CK is the most widely used marker of muscle damage
(e) In severe brain damage CK-BB (The form of CK in the brain) significantly rises in correlation with the damage.

Answer 44

The correct answer is (e) In severe brain damage CK-BB (The form of CK in the brain) significantly rises in correlation with the damage.

CK-BB activity is minimal, even in severe brain damage.

Question 45

A 45 year old woman with a long standing history of high alcohol intake presents to A&E with severe epigastric pain, which radiates to her back and is associated with vomiting. Her pain is partially alleviated by sitting forward.

Which enzyme measurement would be most useful in diagnosis?

(a) ALT
(b) CK
(c) ALP
(d) Amylase
(e) Pepsin

Answer 45

The correct answer is (d) Amylase.

Question 46

An 82 year old woman presented with bone pain, history of fractures and bowing of her tibia. Which blood test would be most useful in diagnosis?

(a) ALT
(b) AST
(c) Calcitonin
(d) ALP
(e) PTH

Answer 46

The correct answer is (d) ALP.

This history points towards Paget’s disease so ALP would be raised.

Question 47

A 64 year old man who smokes and has a FH of cardiovascular disease has recently been started on Atorvastatin. Three weeks after commencing the tablet he complains of generalised muscle pains.

What enzyme measurement would be most useful in diagnosis?

Answer 47

The correct answer is Creatine Kinase.

Question 48

A 52 year old man presented to his GP with a history of exercise-induced central chest pain which radiated to his left arm and neck a week ago. As the pain lasted for half an hour, and subsided on rest, he decided not to go to his GP until today. He’s currently pain free and his ECG at the GP surgery was normal.

Which biochemical measurement might be helpful with the diagnosis?

(a) ANP
(b) BNP
(c) Troponin
(d) CK
(e) LDH

Answer 48

The correct answer is (c) Troponin.

The rise in troponin following an MI or ischaemic event last for between 3-10 days so it’s possible that as this event was 7 days ago that it would still be raised.

Question 49

Which of the following statements about nutritional deficiencies is incorrect?

(a) In haemochromatosis you can have a normocytic picture with Hb in the normal range.
(b) A deficiency in Zinc causes a dermatitis.
(c) Vitamin C, ascorbate, is a water soluble vitamin, that in excess can cause renal stones.
(d) Vitamin A, Retinol, is a fat soluble vitamin, which can cause exfoliation hepatitis if it’s deficient.
(e) Vitamin E, Tocopherol, is a fat soluble vitamin, which can cause neuropathy if it’s deficient.

Answer 49

The correct answer is (d) Vitamin A, Retinol, is a fat soluble vitamin, which can cause exfoliation hepatitis if it’s deficient.

Instead, Vitamin A, Retinol, is a fat soluble vitamin, which can cause exfoliation hepatitis if it’s in excess. A deficiency in vitamin A causes colour blindness.

Question 50

Which of the following options is most increased in a patient with Paget’s disease of the bone?

Choose an option from the following. Each option may be used once, more than once, or not at all.

(a) Acid phosphatase
(b) Alanine aminotransferase
(c) Alkaline phosphatase
(d) Aspartate aminotransferase
(e) Calcium
(f) Cholesterol
(g) Creatinine
(h) Fructosamine
(i) Glucose
(j) HBA1c
(k) Potassium
(l) Sodium
(m) Triglyceride
(n) Urea
(o) Vitamin D

Answer 50

The correct answer is (c) Alkaline phosphatase

Question 51

Which of the following options is increased in a patient with osteomalacia?

Choose an option from the following. Each option may be used once, more than once, or not at all.

(a) Acid phosphatase
(b) Alanine aminotransferase
(c) Alkaline phosphatase
(d) Aspartate aminotransferase
(e) Calcium
(f) Cholesterol
(g) Creatinine
(h) Fructosamine
(i) Glucose
(j) HBA1c
(k) Potassium
(l) Sodium
(m) Triglyceride
(n) Urea
(o) Vitamin D

Answer 51

The correct answer is (c) Alkaline phosphatase.

Calcium is low in osteomalacia. If you see a low calcium and a high Alk Phos the most likely cause is a vitamin D deficiency causing secondary hyperparathyroidism.

Question 52

Which of the following options is increased in acute myocardial infarction?

Choose an option from the following. Each option may be used once, more than once, or not at all.

(a) Acid phosphatase
(b) Alanine aminotransferase
(c) Alkaline phosphatase
(d) Aspartate aminotransferase
(e) Calcium
(f) Cholesterol
(g) Creatinine
(h) Fructosamine
(i) Glucose
(j) HBA1c
(k) Potassium
(l) Sodium
(m) Triglyceride
(n) Urea
(o) Vitamin D

Answer 52

The correct answer is (d) Aspartate aminotransferase

Question 53

Which one of the following is most increased in a patient with jaundice caused by viral hepatitis?

Choose an option from the following. Each option may be used once, more than once, or not at all.

(a) Acid phosphatase
(b) Alanine aminotransferase
(c) Alkaline phosphatase
(d) Aspartate aminotransferase
(e) Calcium
(f) Cholesterol
(g) Creatinine
(h) Fructosamine
(i) Glucose
(j) HBA1c
(k) Potassium
(l) Sodium
(m) Triglyceride
(n) Urea
(o) Vitamin D

Answer 53

The correct answer is (b) Alanine aminotransferase.

AST (d) will also be raised as it’s a marker of liver damage but it will not be as high as ALT.

Question 54

Which of the following is most increased in a patient with jaundice caused by chronic alcoholic cirrhosis?

Choose an option from the following. Each option may be used once, more than once, or not at all.

(a) Acid phosphatase
(b) Alanine aminotransferase
(c) Alkaline phosphatase
(d) Aspartate aminotransferase
(e) Calcium
(f) Cholesterol
(g) Creatinine
(h) Fructosamine
(i) Glucose
(j) HBA1c
(k) Potassium
(l) Sodium
(m) Triglyceride
(n) Urea
(o) Vitamin D

Answer 54

The correct answer is (d) AST.

Question 55

Which of the following is most increased in a patient with prostatic carcinoma?

Choose an option from the following. Each option may be used once, more than once, or not at all.

(a) Acid phosphatase
(b) Alanine aminotransferase
(c) Alkaline phosphatase
(d) Aspartate aminotransferase
(e) Calcium
(f) Cholesterol
(g) Creatinine
(h) Fructosamine
(i) Glucose
(j) HBA1c
(k) Potassium
(l) Sodium
(m) Triglyceride
(n) Urea
(o) Vitamin D

Answer 55

The correct answer is (a) Acid phosphatase.

This is the function of PSA so it’s raised in prostatic carcinoma.

Question 56

Which of the following is low in primary hyperparathyroidism?

Choose an option from the following. Each option may be used once, more than once, or not at all.

(a) Acid phosphatase
(b) Alanine aminotransferase
(c) Alkaline phosphatase
(d) Aspartate aminotransferase
(e) Calcium
(f) Cholesterol
(g) Creatinine
(h) Fructosamine
(i) Glucose
(j) HBA1c
(k) Potassium
(l) Sodium
(m) Triglyceride
(n) Urea
(o) Vitamin D

Answer 56

The correct answer is (o) Vitamin D.

This is because it is consumed in hyperparathyroidism. Remember when you measure vitamin D you measure 25 hydroxy vitamin D, not the activated version.

Question 57

Which of the following rises most in acute renal failure, where the cause is dehydration?

Choose an option from the following. Each option may be used once, more than once, or not at all.

(a) Acid phosphatase
(b) Alanine aminotransferase
(c) Alkaline phosphatase
(d) Aspartate aminotransferase
(e) Calcium
(f) Cholesterol
(g) Creatinine
(h) Fructosamine
(i) Glucose
(j) HBA1c
(k) Potassium
(l) Sodium
(m) Triglyceride
(n) Urea
(o) Vitamin D

Answer 57

The correct answer is (n) Urea.

Electrolytes are well maintained in acute renal failure.

Question 58

Which of the following is true regarding urine dipstick testing?

(a) If the dipstick is negative for blood it reliably excludes haematuria
(b) Haematuria is the only cause of a positive dipstick test for blood
(c) You can reliably exclude bacteriuria if the urine dipstick is negative for nitrites
(d) The urine dipstick detects Bence Jones proteins
(e) Glycosuria detected by the dipstick means the patient has diabetes.

Answer 58

The correct answer is (a) If the dipstick is negative for blood it reliably excludes haematuria

Question 59

Casts detected by urine microscopy are characteristic of which condition?

(a) IgA Nephropathy
(b) Goodpastures syndrome
(c) Wegener’s granulomatosis
(d) Glomerulonephritis
(e) Chronic kidney disease

Answer 59

The answer is (d) Glomerulonephritis

Question 60

Which class of drugs may predispose patients to developing pre-renal AKI?

(a) NSAIDs
(b) Calcineurin inhibitors
(c) ACEi or ARBs
(d) Diuretics
(e) All of the above

Answer 60

The correct answer is (e) all of the above.

NSAIDs(a) reduce afferent arteriole dilatation as do calcineurin inhibitors(b).

ACEi and ARBs(c) increase efferent arteriole constriction

Diuretics(d) cause reduction in sodium and water reabsorption causing hypovolaemia.

Question 61

A 40 year old female presents with a petechial rash over her body and legs and an AKI is diagnosed. What is the most likely cause of her renal failure?

(a) NSAIDs
(b) Systemic vasculitis
(c) Amyloidosis
(d) Tumour lysis syndrome following chemotherapy for lymphoma
(e) Myeloma

Answer 61

The correct answer is (b) Systemic vasculitis.

One of the common mechanisms of renal injury is immune dysfunction causing renal inflammation.

Question 62

A 50 year old male with CKD has been started on Darbepoetin, but does not respond to it. What could be the reason for this?

(a) Iron Deficiency
(b) Malignancy
(c) B12 and folate deficiency
(d) Hyperparathyroidism
(e) All of the above

Answer 62

The correct answer is (e) All of the above.

Darbepoetin is a erythropoiesis stimulating agent which is adminstered in CKD to improve their haemoglobin.

A lack of response is either due to non-compliance or one of the options listed here. TB can also prevent good action of ESAs.

Question 63

Give an example of a cause for hypovolaemic, euvolaemic and hypervolaemic hyponatraemia.

Answer 63

Three causes of each are listed below.

Hypovolaemic - Diarrhoea and vomiting, diuretics, salt-losing nephropathy.

Euvolaemic- SIADH, hypothyroidism, adrenal insufficiency.

Hypervolaemic - Cardiac failure, cirrhosis, nephrotic syndrome.

Question 64

Which of the following statements is true?

(a) Addison’s disease creates a hypovolaemic hyponatraemia where urinary sodium is low (<20 mmol/L) so it classed as a non-renal cause.
(b) The formula for calculating osmalarity is 2(Na+ + K+) +glucose.
(c) Correction of hyponatraemia can cause central pontine myelinolysis if done too quickly, so it’s protocol to correct Na+ by no more than 10mmol/L per hour.
(d) Acute renal failure is a renal cause of hypovolaemic hyponatraemia.
(e) Causes of SIADH include drugs such as opiates, SSRIs and carbamazepine.

Answer 64

The correct answer is (e) Causes of SIADH include drugs such as opiates, SSRIs and carbamazepine.

Addison’s disease (a) is classed as a renal cause, not non-renal, of hypovolaemic hyponatraemia, urinary sodium would be >20mmol/L.

The formula for calculating osmalarity (b) is 2(Na+ + K+) +glucose + UREA which was left out in this option.

The rate of correction of hyponatraemia to aim for is 1mmol/L per hour. A rate of 10mmol/L per hour as in (c) would cause central pontine myelinolysis. On top of the rate, it’s good practice to not increase Na+ by 10 per 24 hours.

Acute renal failure is a cause of hypervolaemia hyponatraemia, not hypovolaemic as in (d).