Chemical Pathology - Clinical Chem

Question 1

st johns wort contains what active compound? commonly used in what condition?

Answer 1

(Hypericum perforatum)

depression

Question 2

is hypocalcaemia or hypercalcaemia associated with depression?

Answer 2

Hypercalcaemia (stones, moans, bones, psychiatric overtones)

Question 3

what’s a colle’s fracture?

Answer 3

= anterior displacement of the radius (i.e. radius towards the PALM of the hand)
falling on an extended wrist, hand splayed towards ground

Question 4

what’s smith’s fracture?

Answer 4

= posterior displacement of the radius (i.e. radius towards the BACK of the hand)
falling on a flexed wrist, inwards

Question 5

what’s pott’s fracture?

Answer 5

ankle fracture involving both tibia and fibula

Question 6

do renal stones cause macroscopic or microscopic haematuria?

Answer 6

macroscopic due to tear in urothelium

microscopic = glomerulonephritis, painless

Question 7

what are the PTH levels in malignancy, primary hyperparathyroidism & sarcoidosis?

Answer 7

malignancy = high PTH
sarcoid = low PTH
primary hyperpara. = inappropriately normal or high

Question 8

are calcium & urate stones radio opaque or lucent?

Answer 8

calcium - radio opaque

urate - radio lucent

Question 9

what is an ophthal. consequence of hypercalcaemia?

Answer 9

band keratopathy

Question 10

give 4 other consequences of hypercalcaemia

Answer 10

osteitis fibrosa cystica
peptic ulcer disease
renal stones
pancreatitis

Question 11

what sign is characteristic of OFC?

Answer 11

‘pepper pot skull’ or ‘salt & pepper’ sign due to resorption of bone

Question 12

what are 4 clinical manifestations of multiple myeloma

Answer 12

CRAB
hypercalcaemia 
renal failure
anaemia 
bone disease - raindrop sign, punched out lesions

Question 13

what are 6 risk factors for renal calcium stones?

Answer 13

FH
dehydration 
hypercalciuria 
hypercalcaemia 
HPT 
recurrent UTI - proteus mirabalis

Question 14

what’s the presentation of renal stones (4)?

Answer 14

pain
haematuria
recurrent infections
renal failure

Question 15

what 3 investigations for renal stones?

Answer 15

CT KUB
stone analysis
urine and serum biochemistry

Question 16

what’s the most common renal calcium stone?

Answer 16

calcium oxalate monohydrate

radio opaque & well circumcised

Question 17

what’s the management of calcium renal stones?

Answer 17

Most stones will pass give painkillers:
•	PR diclofenac is very good
Lithotripsy 
Cystoscopy
Lithotomy 
prevent by drinking lots of water and treating hypercalcaemia

Question 18

what’s the management of hypercalcaemia?

Answer 18

urgent treatment required if over 3mmol/L
fluids - IV saline 0.9% 4 hourly 1L bags
IV furosemide
potentially IV pamidronate later on (not initially)

if not urgent then ensure well hydrated and avoid thiazides. consider parathyroidectomy.

Question 19

what tests are required for parathyroidectomy?

Answer 19

Technetium Sesta MIBI and USS performed
if both concordant whole neck doesn’t need to be opened
if not then open neck and remove largest gland

Question 20

what may be seen on hand XR in hyperparathyroidism?

Answer 20

cystic changes in the radial aspect

Question 21

what do histological brown tumours indicate?

Answer 21

long standing, undiagnosed hyperparathyroidism of excess osteoclast activity
may also see multinucleate giant cells

Question 22

what are the clinical pictures of sarcoidosis (4)?

Answer 22

bilateral hilar lymphadenopathy
non-caseating granulomas
low PTH
summer hypercalcaemia

Question 23

which types of MEN are associated with hypercalcaemia?

Answer 23

MEN 1

MEN 2a