Urinary Stones

Question 1

List the common stone types in desc order?

Answer 1

Calcium OXalate  - 45%
Calcium Oxalate & Phosphate - 25%
Triple Phosphate - 20% (infective)
URic Acid - 5%
Cystine - 3%
Calcium Phosphate - 3%

Question 2

What is a staghorn stone?

Answer 2

One that involved the renal pelvis and calyces

Question 3

Describe the gender differences in stones?

Answer 3

Men are 3x more likely.
Men peak in their 30s
Women peak at 35 & 55

Question 4

How do URinary stones present?

Answer 4

Dysuria
~Pyrexia
Recurrent UTIs
Haematuria

Bladder stones can cause frequency and sudden interruption of stream

Pain depends on location of stone:

• Loin Pain
• Ureteric colic radiating to groin
• Testicualar/vulvar pain
• Suprapubic, groin or penile pain (bladder stones)

Question 5

What blood tests would you run for a stone?

Answer 5

• FBC
• U&E
• Creatinine
• Ca
• Urate
• PTH

Question 6

What other tests can you do for stones?

Answer 6

Urinalysis & culture
24 hr urine collection

CT-KUB
US
IV Urogram

Question 7

What are the types of surgery for stones?

Answer 7

Endoscopic:

• Rigid or Flexible Ureteroscopy
• Flexible Lithoclast
• Holmium Laser

ESWL (Extracorporeal Shock Wave Lithotripsy)

PCNL (Percutaneous Nephrolithotomy)

Open (Partial, simple or total nephrectomy)

Question 8

When would you use ESWL?

Answer 8

ESWL is the first line treatment for most upper tract stones.
Except those >2cm.

Question 9

When would you use Endoscopic treatments?

Answer 9

For bladder stones

Or higher if theres uncontrollable pain, severe obstruction, persistant haematuria or failed ESWL

Question 10

When would you use PCNL?

Answer 10

• Large stones
• Associated PUJ stenosis
• Infundibular stenosis
• Calcyceal distribution- outpouching
• Morbid obesity or skeletal deformity
• Stones which are resistant to ESWL such a cystine stones
• Lack of ESWL

Question 11

What are the types of open stone removal?

Answer 11

Partial Nephrectomy - removes part of the kidney

Simple nephrectomy - removes the whole kidney

Total nephrectomy - removes the kidney, suprarenal gland and surrounding tissue

Question 12

When do you do open surgery?

Answer 12

IF a large stone –> Infection and non-function necessitates kidney removal

Or ESWL/PCNL aren’t available

Question 13

How is a percutaneous nephroplithotomy performed?

Answer 13

• Incision into back into kidneys with guidewire with a needle
• The position of the needle is confirmed by fluoroscopy
• Guidewire is then inserted and needle removed
• Inserts neproscope= removes stones
• Catheter may then be inserted to help with healing process

Question 14

What are the contraindications for a PNL

Answer 14

• Active UTI
• Obesity or unusual body habitus
• small kidneys and severe perirenal fibrosis
• coagulopathy

Question 15

What are the complications of PNL

Answer 15

-Urinary tract injury:
- Pelvic tear
- Urethral tear
- Stricture of PUJ
-Injury to adjacent organs:
• Bowel injury
• Pneumothorax
• Liver, spleen
-Systemic complications:
• Sepsis, Fever
• M
-Pseudoaneurysm or AV fistula

Question 16

How does EWSL work?

Answer 16

• Shock wave therapy on kidney
• Makes large stones smaller and able to pass into the ureters and be excreted in urine
• Carried out with simple analgesia

Question 17

Which stones are ESWL ineffective on?

Answer 17

> 2cm

cystine

Question 18

Minor complications of uteroscopy

Answer 18

• Hematuria
• Fever
• Small ureteric perforation
• Minor vescico-ureteric reflex

Question 19

Major complications of uteroscopy

Answer 19

• Major ureteric perforation
• Ureteric avulsion
• Ureteral necrosis and stricture

Question 20

Indications for uteroscopy

Answer 20

• severe obstruction
• uncontrollable pain
• persistant hematuria
• lack of progression
• failed ESWL
• Patient occupation