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Flashcards in Urolithiasis Deck (30):
1

What is the epidaemiology of stones?

Prevalence in general population = 2-3%

Lifetime risk in males 1:8

M:F = 3:1

Peaks:
-Men = 30
-Women = Bimodal at 35 and 50

Chance of stone recurrence is 50% within 10 years (with 10% within a year)

2

Give the different stone types

Calcium oxalate = 45%

Calcium oxalate + phosphate = 25%

"Triple phosphate" infective = 20%

Calcium phosphate = 3%

Uric acid = 5%

Cystine = 3%

3

What are the symptoms and signs of stones?

Renal pain (fixed in loin)

Ureteric colic (radiating to groin)

Dysuria / haematuria / testicular or vulval pain

Urinary infection

Loin tenderness

Pyrexia

4

What are the investigations for stones?

Not imaging

Blood tests - FBC, U+E, Creatinine

Calcium, Albumin, Urate
-Hypercalcaemia should be excluded

Parathormone

Urine analysis and culture

24 hr urine collections

5

What radiological investigations can you use in stones?

X-ray KUB
-Can show up to 90% of stones

Ultrasound
-May show hydronephrosis

IVU (intravenous urogram)

CT-KUB
-GOLD STANDARD
-Very sensitive

6

What are the indications for surgical treatment?

Obstruction

Recurrent gross haematuria

Recurrent pain and infection

Progressive loss of kidney function

Patient occupation

7

What are the techniques for surgical treatment of stones?

Open surgery (now rare)

Endoscopic surgery

ESWL

8

Open surgery has become far less common with the advent of PCNL and ESWL

What are the advantages and disadvantages of open stone surgery?

Advantage
-Single procedure with least recurrence rate

Disadvantages
-Large scar
-Long hospital stay
-General wound complications

9

What are the indications for open surgery?

Non functioning infected kidney with large stones necessitating nephrectomy

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

10

What is a simple pyelolithotomy?

What is a simple radial nephrotomy?

Small incision made to renal pelvis to remove stone

Having to cut into actual kidney tissue to get to calyx stone

11

What are the indications for simple partial and total nephrectomy?

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

12

How common is contralateral stone formation after a total nephrectomy?

Up to 30%

13

What does PCNL stand for?

Percutaneous Nephrolithotomy

14

What type of stone gives the characteristic staghorn stone appearance?

Triple phosphate

Staghorn calculi are the result of recurrent infection and are thus more commonly encountered in women

15

What are the specific indications for PCNL?

Large stone burden (risk of Steinstrasse)

Associated PUJ stenosis

Infundibular stricture

Calyceal diverticulum

Morbid obestity or skeletal deformity

ESWL resistant stones
e.g. Cystine

Lack of availability of ESWL

16

What is steinstrasse?

"Stone street"

Break up large stone but all the smaller stones black the ureter

17

Why is infundibular stricture and calyceal diverticuluman indication for PCNL?

Can be treated in the same operation

May remove stone with other options but your not dealing with the underlying problem

18

How does PCNL work?

Cystoscopy

Guide wire passed up ureter

Retrograde catheter or balloon catheter

Contrast

Guided by ultrasound or X-ray

19

What are the contraindications for PCNL?

Uncorrected coagulopathy

Active Urinary Tract infection

Obesity or unusual body habitus unsuitable for X-ray tables
-e.g. spinal abnormalities

Relative contraindications include small kidneys and severe perirenal fibrosis

20

What are the complications of PCNL?

Serious complications in the 3-8% range

Local complications:
-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%
-MI 0.1-0.4%

21

What is ESWL?

Extracorporeal Shock Wave Lithotripsy

Shock waves crush stones and smaller pieces pass out of body in urine

Newer generation lithotriptors cause less pain

Treatments are usually done on a day-care basis with simple analgesia

Can be repeated as often as required

22

ESWL is now commonly used for renal and ureteric calculi as first line treatment.

When is it not such a good idea?

Not used as first line treatment for stones >2cms and less effective for lower pole stones

If not effective after 2 treatments then further treatments not justified

Often ineffective for treating cystine stones

23

What are the indications for open ureterolithotomy?

Not suitable for laparoscopic approach

Failed ESWL or ureteroscopy

24

What are the indications for ureteroscopy?

Sever obstruction,

Uncontrollable pain

Persistent haematuria

Lack of progression

Failed ESWL and patient occupation

25

What is the standard instument for treating lower ureteric stones?

Rigid ureteroscope
-90-100% success rate

For proximal stones the success rate is lower at 60-70%

26

Apart from rigid ureteroscope what other options do you have for endoscopic ureteric stone surgery?

Flexible ureteroscope

Flexible lithoclast

Holmium laser

27

What are the complications of ureteroscopy?

Minor:
-Haematuria, fever, small ureteric perforation, minor-ureteric reflux

Major:
-Major ureteric perforation, ureteric avulsion, ureteral necrosis and stricture formation

28

What are the signs and symptoms of bladder stones?

Suprapubic/ groin/ penile pain

Dysuria, frequency, haematuria

Urinary inefction (persistent)

Sudden interuption of urinary stream

Usually secondary to outflow obstruction

29

How are bladder stones treated?

Most treated endoscopically

Larger stones can be treated by open excision

30

What percentage of gallstones are radio-opaque (i.e. visible on non-contrast X-ray)?

About 10 %