Kidney stones Flashcards
(31 cards)
other names for renal stones
- renal calculi
- urolithiasis
- nephrolithiasis
What is urolithiasis?
Urinary stone
Presentation of renal stones
- renal colic - loin to join pain
- haematuria
- N+V
- reduced urine output
Intial investigations of renal stones before imaging
- urine dipstick + cultures
- pregnancy test
- U&Es
- FBC, CRP
- calcium/urate levels
- clotting
- blood cultures if pyrexia or signs of sepsis
Complications of renal stones
- obstructions > AKI
- infection > obstructive pyelonephritis
Diagnosis of urinary stones
- CT scan of kidneys, ureters + bladder non contrast
- USS KUB (pregnant women + children*
What type of renal stones will show up on abdominal X ray?
calcium based stones
(not uric acid stones)
What are the types of urinary stones?
- calcium oxalate stone (most common)
- mixed calcium phosphate + calcium oxalate stone
- magnesium ammonium phosphate stones
- uric acid stone
- cystine stone
Risk factors for calcium collecting into stones
hypercalcaemia
low urine output
Types of urinary stones + what is associated with each type
- calcium oxalate: hypercalcaemia, hyperparathyroidism, hyperoxaluria
- mixed calcium phosphate + calcium oxalate: alkaline urine
- magnesium ammonium phosphate: urea splitting bacteria
- uric acid: gout + myoproliferative disorders
- cystine: inherited cystinuria
Clinical presentation of urinary stones (renal, ureteric + bladder)
- renal stones: continuous dull ache in lions
- ureteric stones: renal colic (radiates from loin to groin), sweaty, restless with N+V
- bladder stones: strangury
- recurrent UTI, haematuria or rental failure
What is strangury?
Urge to pass something that will not pass
(Feeling like they need to pee all the time)
Management of ureteric stones
- analgesia - NSAIDs e.g. IM diclofenac or IV paracetamol
- high fluid intake
- urine sieved for analysis
- antiemetics e.g. metoclopramide, cyclizine
- watchful waiting if <5mm
- surgery for larger stones
- tamsulosin to help pass distal ureteric stone <10mm
- thiazidens
What drug can be used to decrease urinary stones?
Thiazide
Increases distal tubular calcium resorption
Interventional treatment of urinary stones
- extracorporeal shock wave lithotripsy
- ureteroscopy
- percutaneous nephrolithotomy
- open surgery
What is extracorporeal shock wave lithotripsy?
- non-invasive procedure
- shock waves break down stones into smaller fragments > easier to pass
- suitable for smaller stones <2cm
What is ureteroscopy?
- for stones in ureter + smaller stone in kidney
- use of thin, flexible camera to visualise + access stones
- can remove or fragment stones
What is percutaneous nephrolithotomy?
- for larger stones in kidney >2cm
- invasive
- small incision to access + insert neprhoscope > remove or breakdown stones
- neprhostomy tube left in place after to drain the kidneys
- done under GA
What is the most common composition of ureteric stones?
Calcium oxalate stone
What factors predispose the development of ureteric stones?
Low urine volume
Hypercalcaemia
Hyperoxaluria
(Calcium oxalate is most common)
Features of hypercalcaemia
‘Bones, stones, thrones, moans, groans’
- bone pain + increased fracture risk
- renal sones
- polyuria
- constipation
- confusion + mood disturbance
- abdominal pain
What is a staghorn calculus?
Renal stone in the renal collecting system
What are the most common locations of stones in the urinary tract?
Pelviureteric junction
Pelvic brim
Vesicoureteric junction
management of recurrent stones
- increase oral fluid intake
- add fresh lemon juice to water
- avoid carbonated drinks
- reduce dietary salt intake
- maintain a normal clacium intake
