Urinary tract stones Flashcards
Common location of renal stones in the renal pelvis
Vesicle-ureteric junction
Examples of stones complications
- AKI
- pyelonephritis
Underlying principles of stones
- solute
- — urinary stone inhibitors
- — solvent
Main causes of hypercalcaemia
- Ca supplements
- hyperPTHism
- cancer
Colour of Ca-oxalate stones
Red/dark brown
Colour of uric acid stones
Red/brown
Colour of cystine stones
Yellow/pink
AR disease associated with cystine stones
Cystouria
Colour of Ca-phosphate stones
Dirty white
Struvite stones are associated with
Bacterial infection
Colour of struvite stones
Dirty white staghorn
Acidic renal stones
- calcium oxalate
- uric acid
Normal pH renal stones
Cystine
Alkaline renal stones
- calcium phosphate
- struvite
Radiopaque renal stones
- calcium oxalate
- calcium phosphate
- struvite
Radiolucent renal stones
- cystine
- uric acid
Bacterial pathogenesis of staghorn calculus (stones in pelvis & calyces)
Urine breakdown —> ammonia
General renal symptoms of renal stones (just to be aware of)
- haematuria
- N/V
- reduced urine output
- sepsis
Renal colic pain in renal stones
- unilateral
- loin to groin
- colicky
1st line Ix of renal stones that needs to be done within 24hrs
Non-contrast CT KUB
Haematuria in urine dipsticks can exclude … but cannot exclude …
- infection
- kidney stones
Limitation of USS KUB as compared to CT
Less effective
USS KUB can be helpful in
- children
- pregnancy
Most effective painkiller in renal stones that is also given IM
NSAIDs
An alternative to NSAIDs
Paracetamol
Other meds given whilst relieving stones
- antiemetics
- Abx
50-80% of stones pass spontaneously. Watchful waiting for those stones that are size of
<5mm
An example of alpha-blocker
Tamsulosin
Purpose of alpha-blocker
Aid stone passage
Surgical intervention is used when the stone is
> 10mm
1st line surgical intervention that directs shockwaves
Extracorporeal shock wave lithotripsy (ESWL)
2nd line surgical intervention that uses camera & targeted laser
Ureteroscopy and laser lithotripsy
3rd line surgical intervention that requires GA and nephrotoxic bag
Percutaneous nephrolithoromy (PCNL)
Open surgery is not preferred because
- rare
- too invasive
Most common renal stones composition
Calcium based
