Renal Stones Flashcards
Where do renal stones form?
Collecting ducts
Where are renal stones classically deposited?
Pelviureteric junction, pelvic brim, vesicoureteric junction
What is the most common renal stone?
Calcium oxalate
What are some less common renal stones?
Uric acid, struvite, cystine
How do renal stones present?
Renal colic, restlessness, nausea and vomiting, haematuria, dysuria
Where is renal colic due to obstruction of the kidney?
Loin
Where is renal colic due to obstruction of the mid-ureter?
Pain similar to appendicitis or diverticulitis
Where is renal colic due to obstruction of the lower ureter?
Scrotum/penile tip/labia majora
What is a urine dipstick usually positive for?
Blood, leucocytes, nitrites
What blood tests would you do?
FBC, CRP, U&E
What is the gold standard investigation?
Non-contrast CT KUB
What imaging would you do in pregnancy?
USS KUB
What are some differential diagnoses?
Appendicitis, diverticulitis, ruptured AAA
What symptomatic relief would you start?
Hydration, NSAIDs/opioids
What stone size pass spontaneously?
<5mm
What should you start if the stone is over 5 mm or pain is not resolving?
Medical expulsive therapy
What drugs help stones pass and reduce analgesia requirements?
Nifedipine, alpha blockers
What other options are there if stones aren’t passing?
Extracorporeal shockwave lithotripsy, ureteroscopy, percutaneous nephrolithotomy
What are indications urgent intervention is needed?
Intolerable pain/vomiting, signs of obstruction/infection, AKI
What general prevention can you recommend?
Decrease sodium and protein intake, increased citrus fruit, adequate fluid intake
What are risk factors for renal stones?
Chronic dehydration, obesity, high protein/salt diet, recurrent UTIs, hyperparathyroidism, congenital abnormalities
