UROLITHIASIS

Question 1

what is the incidence of kidney stones?

Answer 1

Prevalance in general population 2-3%
Lifetime risk in males 1:8
M:F ratio 3:1
Peak age in men is 30 years
Women bimodal peak – 35 and 55 years
Chance of stone recurrence is 50% within 10 years (with 10% within a year)
‘Colic’ is the commonest cause of urological emergency admission

Question 2

what are the different compositions for kidney stones?

Answer 2

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

Question 3

what are symptoms and signs of kidney stones?

Answer 3

Renal pain (fixed in loin)
Ureteric colic (radiating
to groin)
Dysuria / haematuria /
testicular or vulval pain
Urinary infection
Loin tenderness
Pyrexia

Question 4

what investigations are done for kidney stones?

Answer 4

Blood tests - FBC, U&E, Creatinine
Calcium, Albumin, Urate
Parathormone
Urine analysis and culture
24hr urine collections

Question 5

what radiological investigations are done for kidney stones?

Answer 5

KUB
(KIDNEY/URETER/BLADDER)

Ultrasound

IVU
(intravenous urogram)

CT KUB

CT KUB/Urogram – 3D

Question 6

what are indications for surgical treatment of kidney stones?

Answer 6

Obstruction.
Recurrent gross haematuria.
Recurrent pain and infection.
Progressive loss of kidney function.
Patient occupation.

Question 7

what techniques are there for surgical treatment?

Answer 7

Open Surgery (now very rare)
Endoscopic Surgery
ESWL

Renal stones
Ureteric stones
Bladder stones

Question 8

what is the advantage of open surgery for renal stone treatment?

Answer 8

Single procedure with the least recurrence rate.

Question 9

what is the diasadvantage of open surgery for renal stone treatment?

Answer 9

Large scar, long hospital stay, general wound complications, longer recovery.

Question 10

what are indications for open surgical stone treatment?

Answer 10

Non functioning infected kidney with large stones necessitating nephrectomy.

Cases which for technical reasons cannot be managed by PCNL or ESWL.

Question 11

what is a simple pyelolithotomy?

Answer 11

Simple pyelolithotomy permits the facile removal of stones from the renal pelvis, and extended pyelolithotomy and pyelonephrolithotomy have allowed the re- moval of branched calculi that extend into the caliceal system without disrupting the renal parenchyma

Question 12

what is a simple radial nephrotomy?

Answer 12

radial nephrotomy incision during unclamped PN is less likely to transect a major intrarenal vessel, and may therefore result in less bleeding

Question 13

when is a Simple partial or total nephrectomy done?

Answer 13

Non functioning kidney with large staghorn stones or elderly frail patients with complex stones and normal contralateral kidney.

Contralateral stone formation in up to 30% after total nephrectomy has been reported.

Question 14

what are specific indications for a PCNL?

Answer 14

Large stone burden (risk of Steinstrasse)
Associated PUJ stenosis.
Infundibular stricture.
Calyceal diverticulum.
Morbid obesity or skeletal deformity.
ESWL resistant stones e.g. Cystine.
Lack of availability of ESWL.

Question 15

what are the stage before guidance of ultrasound or xray for a PCNL?

Answer 15

Question 16

what are contraindications for a PCNL?

Answer 16

Uncorrected coagulopathy.
Active Urinary Tract Infection.
Obesity or unusual body habitus unsuitable for X-ray tables.
Relative contraindications include small kidneys and severe perirenal fibrosis.

Question 17

what are complications of PCNL?

Answer 17

Serious complications - in the 3-8% range.

Local complications includes:
Pseudoaneurysm or AV fistula 0.5-1%
UT injury: Pelvic tear 8-15%
Ureteral tear 5%
Stricture of PUJ 0.1-0.8%

Injury to adjacent organs:
Bowel injury 0.1%
Pneumothorax 0.1-0.3%
Liver, spleen Very rare

Systemic complications:

Fever, sepsis 0.2-0.6%
Myocardial infarction 0.1-0.4%

Question 18

what is ESWL?

Answer 18

Now commonly used for renal and ureteric calculi as first line treatment
Newer generation lithotriptors cause less pain
Treatments are usually done on a on a day-case basis with simple analgesia
Can be repeated as often as required

Not used as first line treatment for stones > 2cms and less effective for lower pole stones
If not effective after two treatments then further treatments not justified
Often ineffective for treating cystine stones

Question 19

Indications for open ureterolithotomy:

Answer 19

Not suitable for laparoscopic approach.
Failed ESWL or ureteroscopy.

Question 20

Indications for ureteroscopy:

Answer 20

Severe obstruction, uncontrollable pain, persistent haematuria, lack of progression, failed ESWL and patient occupation.

The rigid ureteroscope is the standard instrument for treating lower ureteric stones with a 90-100% success rate.

The success rate for proximal stones is lower at 60-70%.

Question 21

what instruments are available for use in uteroscopy?

Answer 21

Flexible ureteroscopes
Flexible lithoclast
Holmium laser

Question 22

what are minor complications of uteroscopy?

Answer 22

Haematuria, fever, small ureteric perforation, minor vesico-ureteric reflux.

Question 23

what are major complications of a uteroscopy?

Answer 23

Major ureteric perforation, ureteric avulsion, ureteral necrosis and stricture formation.

Question 24

what are bladder stones?

Answer 24

Suprapubic / groin / penile pain
Dysuria, frequency, haematuria
Urinary infection (persistent)
Sudden interruption of urinary stream
Usually secondary to outflow obstruction
Most treated endoscopically
Larger stones can be treated
by open excision