Nephro-urolithiasis Flashcards
Which gender is more commonly affected by stones?
Males
M:F ratio of 3:1
Peak age in men is 30
Chance of stone recurrence is 50% within 10 years, 10% within a year
What are the types of stones and their incidence?
¨Calcium oxalate 45%
¨Calcium oxalate + phosphate 25%
¨‘Triple phosphate’ (infective) 20%
¨Calcium phosphate 3%
¨Uric acid 5%
¨Cystine 3%
What are the symptoms and signs?
Renal pain (fixed in loin)
Ureteric colic (radiating to groin)
Dysuria / haematuria /testicular or vulval pain
Urinary infection
Loin tenderness
Pyrexia
What are initial investigations for kidney stones?
Blood tests - FBC, U&E, Creatinine
Calcium, Albumin, Urate
Parathormone
Urine analysis and culture
24hr urine collections
MIght show low citrate - citrate can help prevent crystal formation
What are the readiological investigations for stones?
KUB - kidney, ureter, bladder (shows up the calcium containing stones - over 90% of stones)
U/Sound
IVU - intravenous urogram
CT KUB
What are indications for surgial treatment?
Obstruction.
Recurrent gross haematuria.
Recurrent pain and infection.
Progressive loss of kidney function.
Patient occupation.
What are the techniques for surgical treatment?
Open Surgery (now rare)
Endoscopic Surgery
ESWL - extra corporeal shockwave therapy
Renal stones
Ureteric stones
Bladder stones
What are the advantages and disadvantages of open stone surgery?
The advantage of open surgery is:
Single procedure with the least recurrence rate.
The disadvantages of open surgery are:
arge scar, long hospital stay, general wound complications, longer recovery.
What are indications for open surgical stone treatment?
Non-functioning infected kidney with large stones necessitating nehrectomy
Cases which for technical reasons cannot be managed by PCNL or ESWL.
PCNL - Percutaneous Nephrolithotomy
When is there a need for simple partial and total nephrectomy?
Non functioning kidney with large staghorn stones or elderly frail patients with complex stones and normal contralateral kidney.
Note: ¨Contralateral stone formation in up to 30% after total nephrectomy has been reported.
What are indications for PCNL?
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.
What are contraindications for PCNL?
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.
What are the local complications of PCNL?
Pseudoaneurysm or AV fistula 0.5-1%
UT injury: Pelvic tear 8-15%
Ureteral tear 5%
Stricture of PUJ 0.1-0.8%
What injury to adjacent organs can occur as a result of PCNL?
Adjacent organs:
Bowel injury 0.1%
Pneumothorax 0.1 - 0.3%
Liver, Spleen (very rare)
What are the systemic complications of PCNL?
Fever, sepsis - 0.2-0.6%
Myocardial infarction - 0.1-0.4%
Mechanism of ESWL
What is often the first line treatment for renal and ureteric calculi?
ESWL
¨Treatments are usually done on a on a day-case basis with simple analgesia
Can be repeated as often as required
When is ESWL not effective?
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
What are the common places for a stone to get lodged?
What is IVU?
The IVU is a special diagnostic test that follows the time course of excretion of a radiopaque contrast dye through the kidneys, ureters (the tubes that carry urine from the kidneys to the bladder) and bladder after it is injected into a vein in your arm.
The discovery of X-rays and the use of contrast material in 1906 allowed accurate diagnosis and localisation of ureteric stones.
The introduction of the IVU revolutionised the diagnosis of ureteric stones.
Indications for open ureterolithotomy - open surgery for ureteric stones
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 and patient occupation.
Lower ureteric stones have a higher success rate when compared with proximal stones
What are the minor and major complications of ureteroscpy?
Minor complications: 0-30%
Haematuria, fever, small ureteric perforation, minor vesico-ureteric reflux.
Major complications:
Major ureteric perforation, ureteric avulsion, ureteral necrosis and stricture formation.
What are the presenting features of bladder stones?
Suprapubic / groin / penile pain
Dysuria, frequency, haematuria
Urinary infection (persistent)
Sudden interruption of urinary stream
Usually secondary to outflow obstruction
How are bladder stones usually treated?
Most treated endoscopically
Larger stones can be treated
by open excision
