Urolithiasis - Kidney stones Flashcards
What is urolithiasis?
Urinary tract stones
Relative incidence of stones
M:F ratio 3:1
Peak age in men is 30
What is the most common cause of urological emergency admission?
Intermittent pain (renal colic) when a stone gets lodged in your urinary tract
Severe
Types of kidney stones
Calcium oxalate - 45%
Calcium oxalate + phosphate
Triple phosphate (infective)
Uric acid
Calcium phosphate - 3%
Cystine
Symptoms and signs of kidney stones (6)
Renal pain (fixed in loin)
Ureteric colic (radiating to groin)
Dysuria / haematuria /
testicular or vulval pain
Urinary infection
Loin tenderness
Pyrexia
Investigations carried out for stones
Blood tests - FBC, U&E,
Creatinine
Calcium, Albumin, Urate
Parathormone (parathyroid hormone)
Urine analysis and culture
24hr urine collections
Which radiological techniques are used to look at stones? (5)
KUB Radiograph - x ray (Kidney/Ureter/Bladder)
USS
IVU (IV urogram)
CT KUB
CT KUB/Urogram - 3D reconstruction
Indications for surgical treatment of stones (5)
Obstruction
Recurrent gross haematuria
Recurrent pain and infection
Progressive loss of kidney function
Patient occupation
Within urology, what types of stones can you get?
Renal stones
Ureteric stones
Bladder stones
What are some surgical techniques? (4)
Open surgery - now very rare
Endoscopic surgery
ESWL - Extracorporeal shock wave lithotripsy - shocks the stones into smaller pieces - common
Percutaneous nephrolithotomy - PCNL - keyhole surgery
Indications for open surgery for stone treatment?
Non-functioning infected kidney with large stones necessitating nephrectomy
Cases which cannot be managed by PCNL or ESWL
Indications for Percutaneous nephrolithotomy
Large stone burden (risk of Steinstrasse)
Associated PUJ stenosis.
Infundibular stricture.
Calyceal diverticulum - a urine containing outpouching of a calyx into the renal parenchyma
Morbid obesity or skeletal deformity.
ESWL resistant stones e.g. Cystine or lack of availability of ESWL.
How is PCNL carried out?
Guide wire inserted into urinary tract
Retrograde catheter or balloon catheter inserted into the kidney through the ureter
Contrast given
Contraindications for PCNL
Uncorrected coagulopathy.
Active UTI.
Obesity or unusual body habitus unsuitable for X-ray tables.
Relative contraindications include small kidneys and severe perirenal fibrosis.
Local Complications of PCNL
Pseudoaneurysm or AV fistula
UT injury - pelvic tear, ureteral tear, stricture of PUJ
Injury to adjacent organs - bowel injury, pneumothorax
Systemic - fever, sepsis, MI (rare)
What is first line treatment for renal and ureteric calculi?
Extracorporeal Shock Wave Lithotripsy = ESWL - simple analgesia and can be repeated as often required
When is ESWL not used?
If stone is >2cm
It is also less effective for stones in the lower pole (bottom end of the kidney)
Often ineffective for treating cystine stones
Indications for Open surgery for ureteric stones
If not suitable for laparoscopic approach.
Failed ESWL or ureteroscopy.
Indications for ureteroscopy (endoscopic surgery)
Severe obstruction
Uncontrollable pain
Persistent haematuria
Lack of progression
Failed ESWL
Patient occupation.
How successful is ureteroscopy?
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%.
Surgical options for ureteric or renal stones?
Flexible ureteroscopes
Flexible lithoclast - combination of ultrasound and pneumatic lithotripsy
Holmium laser
Complications of Ureteroscopy: Minor and Major
Minor (0-30%) - haematuria, fever, small ureteric perforation, minor vesico-ureteric reflux
Major - major ureteric perforation, ureteric avulsion, ureteral necrosis and stricture formation
What is ureteric avulsion?
Damage to the ureter almost always related to the use of an ureteroscope too large to be readily accommodated by the ureter
Presentation of Bladder stones
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
