Lecture 18: Urolithiasis Flashcards
urolithiasis definition
- urinary tract stones are solid concretions or crystal aggregations formed in the urinary system from substances that are present in urine.
what is renal colic?
a condition characterised by severe pain caused by the presence of a stone in the urinary tract
what are modifiable risk factors for urolithiasis?
- obesity
- dehydration
- diet rich in oxalate-rich foods like fruits, nuts, and cocoa
what are non-modifiable risk factors for urolithiasis?
- previous stone disease
- anatomical abnormalities of the collecting system
- family histology
- underlying medical condition, such as:
Hyperparathyroidism
Renal tubular acidosis
Myeloproliferative disorders
All chronic diarrhoeal conditiona
urolithiasis signs and symptoms
- severe, intermittent loin pain that can radiate to the groin (‘loin to groin pain’)
- restlessness (patients often unable to get comfy and pace around/hunch over in pain)
- dysuria and haematuria: either macroscopic or microscopic
- nausea and vomiting
- secondary infection may cause fever or signs of sepsis
urolithiasis epidemiology
- common condition, affecting approx 2-3% of western population
- more frequenct in males and individuals less than 65 y/o
what is the relative incidence of calcium oxalate stones?
- calcium oxalate: 45%
urolithiasis investigations
Bedside:
- urinalysis
- urine MC+S: check for infection
- observations to look for any signs of sepsis
Blood tests:
- FBC
- U+Es
- calcium and uric acid to identify underlying metabolic conditions predisposing to stone formation
Radiological investigations:
- non-contrast helical CT KUB is the gold standard for identifying renal calculi
- an x-ray for managing renal colic if confirmed stone on CT KUB
urolithiasis indications for surgical treatment
- obstruction
- recurrent gross haematuria
- recurrent pain and infection
- progressive loss of kidney function
- patient occupation
what are the indications for an open surgical stone treatment?
- non-functioning infected kidney with large stones necessitating nephrectomy
- cases which for technical reasons cannot be managed by PCNL or ESWL.
what are the indications for percutaneous nephrolithotomy (PCNL)?
- large stone burden
- associates PUJ stenosis
- infundibular stricture
- calyceal diverticulum
- morbid obesity or skeletal deformity
- ESWL resistant stones e.g. cystine
- lack of availability of ESWL
what are the contraindications for PCNL?
- uncorrected coagulopathy
- active urinary tract infection
- obesity or unusual body habitus unsuitable for X-ray tables
- relatve contraindications include small kindeys and severe perirenal fibrosis
complications of PCNL
serious complications: 3-8% risk
local complications:
- pseudoaneurysm or AV fistula
- UT injury: pelvic tear, ureteral tear, stricture of PUJ
injury to adjacent organs:
- bowel injury
- pneumothorax
- liver, spleen (very rare)
systemic:
- fever, sepsis
- myocardial infarction
what does ESWL stand for?
how does it work?
extracorporeal shock wave lithotripsy
- shock waves cruch stones into smaller fragments so they can pass out of body in urine
what is commonly used as a first-line treatment for renal and ureteric calculi <2cm ?
ESWL
