Chem Path: Clinical Chem CPC

Question 1

What electrolyte imbalance usually presents with depression?

Answer 1

Hypercalcaemia

Question 2

What cardiac affect does hyperkalaemia have?

Answer 2

Asystole

Question 3

What cardiac affect does hypokalaemia have?

Answer 3

VF

Question 4

What does hypocalcaemia cause?

Answer 4

Nerve irritability which causes seizures

Question 5

What is colle’s fracture?

Answer 5

Radial head displaced backwards (away from palm)

Question 6

What is Smith’s fracture?

Answer 6

Caused by falling on flexed wrist - Radial head will be displaced forwards, towards the palm

Question 7

What is Pott’s fracture?

Answer 7

Ankle fracture involving tibia and fibula

Question 8

How does subacute bacterial endocarditis present?

Answer 8

Get lots of microemboli, splinter haemorrhages, splenomegaly and microscopic haematuria

Question 9

How would acute rheumatic fever present?

Answer 9

Sore throat in childhood and then mount autoimmune antibodies

Question 10

What is the first investigation you will do in someone with depression and renal stones?

Answer 10

Test calcium. If calcium is normal then no need to measure PTH

Question 11

What are the 3 common causes of hyperCa

Answer 11

Malignancy
Primary hyperparathyroidism
Sarcoidosis

Question 12

What investigation can distinguish between these?

Answer 12

PTH

Question 13

How does hypercalcaemia present?

Answer 13

Moans, bones, groans, stones

Band keratopathy

Osteitis fibrosa et cystica

Pepper pot skull

Nephrocalcinosis

Pancreatitis

Question 14

What kind of renal stones are the most common?

Answer 14

Calcium oxalate

Question 15

Which stones cause gout and can they be seen on Xray?

Answer 15

Uric acid stones and they cannot be seen on x ray

Question 16

How do you treat patients with hypercalciuria but without hypercalcaemia?

Answer 16

Thiazide diuretic

Question 17

What organism grows with renal stones

Answer 17

Proteus mirabilis

Question 18

Is all Vit D converted to 25 hydroxy vitamin D?

Answer 18

Yes, as all of them undergo first pass hepatic metabolism

Question 19

How do you urgently manage hypercalcaemia

Answer 19

IV 0.9% saline, 1L over 1 hour

Question 20

When would you give bisphosphonates for hypercalcaemia

Answer 20

Due to malignancy

Question 21

What is the problem with bisphosphonates

Answer 21

They bind to calcium in the bone, and after operation, calcium falls really low.

Question 22

What indicates urgent treatment for hypercalcaemia

Answer 22

Calcium of more than 3mmol/L

Question 23

Why is hypercalcaemia above 3mmol/L dangerous?

Answer 23

Calcium is an osmotic diuretic and will cause polyurea leading to dehydration. Creatinine rises, and you have renal failure, leading to more dehydration. Then calcium rises even more giving rise to arrythmias

Question 24

How do you manage hypercalcaemia beyond 3mmol/L

Answer 24

0.9% saline (dextrose if liver failure)

Furosemide if cannot give saline

IV pamidronate if its malignancy - prevent spread to bone and will cause Ca to fall after 4 days

Question 25

How would you treat hyperparathyroidism?

Answer 25

fluid
avoid thiazide as they will increase plasma calcium concentration
Take out parathyroids

Question 26

What can you see in the bone histology of PTH patients

Answer 26

Brown tumours - multinucleate giant cells

Question 27

What would the hand x ray of a patient with long standing PTH show

Answer 27

Radial aspect cystic changes

Question 28

Who would you expect to have looser’s zones

Answer 28

People with vit D deficiency

Question 29

What is the hallmark of sarcoidosis

Answer 29

Non caseating granulomas

Question 30

How does sarcoidosis lead to hypercalcaemia

Answer 30

Macrophages secrete 1 alpha hydroxylase which activates vit D and leads to hypercalcaemia