Urinary stone disease

Question 1

Urolithiasis risk factors

Answer 1

dehydration
cystinuria
hypercalciuria, hypercalcaemia, hyperparathyroidism
high dietary oxalate
renal tubular acidosis
gout (for uric acid stones)
polycystic kidney disease

Question 2

Drug causes of urolithiasis

Answer 2

drugs that promote calcium stones: loop diuretics, steroids, acetazolamide, theophylline

Question 3

Composition of urinary stones

Answer 3

calcium oxalate
uric acid
struvite
cystine
calcium phosphate

Question 4

What is a specific risk factor for development of a struvite urinary stone?

Answer 4

infection (due to bugs in urine)
(often large –> staghorn stones)

Question 5

What causes cystine urinary stones?

Answer 5

genetic predisposition
cystinuria

Question 6

Presentation of urolithiasis

Answer 6

loin pain - intermittent, sharp, loin to groin
recurrent UTI
non visible/visible haematuria
sepsis

Question 7

If a kidney stone completely blocks a ureter - what could happen?

Answer 7

infected obstructed kidney

Question 8

If a patient presents with renal colic and fever, what should be suspected?

Answer 8

infected obstructed kidney

Question 9

How should an infected obstructed kidney be managed?

Answer 9

stent ureter/nephrostomy to drain kidney
antibiotics
fluid resuscitation

Question 10

How many urinary stones can be seen on xray?

Answer 10

80-90%

Question 11

How many urinary stones can be seen on non-contrast CT?

Answer 11

100%

Question 12

What type of scan is not good for visualising the ureters?

Answer 12

ultrasound
ureters deep and neer vertebra transverse processes

Question 13

When should you intervene in urolithiasis?

Answer 13

pain
increasing size
obstruction

Question 14

How can urolithiasis be treated?

Answer 14

lithotripsy
ureteroscopy + laser
percutaneous nephrolithotomy (for v large)
open surgery (rarely used now)

Question 15

Contraindications to lithotripsy

Answer 15

pregnancy
anti-coagulants

Question 16

What is the composition of a staghorn normally?

Answer 16

struvite (infection) stones

Question 17

When can dissolution therapy be used for urolithiasis?

Answer 17

uric acid stones - urinary alkalinisation - sodium bicarbonate/potassium citrate

cystine stones - D penicillamine, alkalinisation, high fluid load

Question 18

How can urolithiasis be prevented?

Answer 18

fluids
occupational adjustment - not sedentary for long periods, not as hot working environment
reduction in consumption of animal proteins, salt, oxalate rich foods and calcium

Question 19

Other than an infected obstructed kidney, when might a ureteric stent need to be placed for urolithiasis?

Answer 19

AKI

Question 20

If a patient is young and frequently has kidney stones - what should you be suspicious of?

Answer 20

cystinuria