Urolithiasis

Question 1

What is the lifetime risk of stones in males?

Answer 1

1 in 8

Question 2

What is the ratio of incidence of stones in males vs females?

Answer 2

M:F - 3:1

Question 3

At what age to men peak in stones incidence?

Answer 3

30s

Question 4

At what age to women peak in stones incidence?

Answer 4

35 and 55

Question 5

What is the likelihood of stone recurrence?

Answer 5

50% in 10 years

Question 6

What are the main types of stones and their relative incidence?

Answer 6

Calcium oxalate 45%
Calcium oxalate + phosphate 25%
‘Triple phosphate’ (infective) 20%
Calcium phosphate 3%
Uric acid	5%
Cystine 3%

Question 7

What is the typical presentation of stones?

Answer 7

Loin --> groin pain 'colic'
Dysuria
Haematuria
Testes/vulval pain
Urinary infection
Loin tenderness
Pyrexia

Question 8

How should stones be investigated?

Answer 8

FBC, U+E, Creatinine
Calcium
Albumin
Urate
Parathormone
Urine analysis/culture
24hr urine
KUB/USS
IVU/CT KUB

Question 9

What are the indications for surgery in renal stones?

Answer 9

Obstruction
Recurrent haematuria 
Recurrent pain/infection
Progressive loss of kidney function
Patient occupation

Question 10

What are the more common types of surgery for stones?

Answer 10

Open surgery (rare)
Endoscopic surgery
ESWL

Question 11

What are the advantages of renal stone open surgery?

Answer 11

Single procedure, lowest risk of recurrence

Question 12

What are the disadvantages of renal stone open surgery?

Answer 12

Large scar
Risk of infection
Risk of complications
Longer recovery

Question 13

What are the indications for open surgical stone treatment?

Answer 13

Non-functioning infected kidney - nephrectomy

PCNL/ESWL not possible

Question 14

What are the indications for partial/total nephrectomy in stones?

Answer 14

Non-functioning kidney with staghorn stones

Elderly/frail patients with complex stones

Question 15

What is the risk associated with total nephrectomy?

Answer 15

Contralateral stone formation (30%)

Question 16

What is PCNL?

Answer 16

Percutaneous Nephrolithotomy

Question 17

What are the indications for PCNL?

Answer 17

Large stone burden
PUJ stenosis
Infundibular stricture
Calyceal diverticulum
Morbid obesity
ESWL resistant stones

Question 18

Which type of stones are resistant to ESWL?

Answer 18

Cystine

Question 19

What are the contraindications for PCNL?

Answer 19

Uncorrected coagulopathy
Active UTI
Obesity/unusual body habitus unsuitable for X-ray table
Small kidneys
Severe perirenal fibrosis

Question 20

What complications are associated with PCNL?

Answer 20

Pseudoaneurysm 
Pelvic/ureteral tear 
Stricture
Bowel injury
Pneumothorax
Fever/sepsis
MI

Question 21

What is ESWL?

Answer 21

Extracorporeal Shock Wave Lithotripsy

Question 22

When is ESWL contraindicated?

Answer 22

Stones >2cm
Lower pole stones
Not effective after 2 treatments
Not for cystine stones

Question 23

What are the indications for open ureterolithotomy?

Answer 23

Not suitable for laparoscopy

Failed ESWL/ureteroscopy

Question 24

What are the indications for ureteroscopy?

Answer 24

Severe obstruction
Uncontrollable pain 
Lack of progression
Persistent haematuria 
Failed ESWL
Occupation

Question 25

What is the success rate of ureteroscopy for stone removal?

Answer 25

90-100% lower

60-70% upper

Question 26

What complications are associated with ureteroscopy?

Answer 26

Minor:
Haematuria, fever, small ureteric perforation, minor vesico-ureteric reflux
Major:
Ureteric perforation, necrosis, avulsion, stricture