Kidney - Stones

Question 1

Risk factors for stone formation

Answer 1

Dehydration
High Ca, PTH
High dietary cystinuria
Gout
Loops, CS, acetazolamide

Thiazides protective for stones

Question 2

Presentation
Investigations

Answer 2

Loin to groin, colicky pain
Acute, sudden severe
May have urinary symptoms, septic if infected

Urinedip, MCS
U&E - assess renal function
FBC, CRP - associated infection
Ca/urate - underlying causes

NON CONTRAST KUB

Renal stones
-U5mm, asymptomatic => watch and wait
-5-10mm => lithotripsy + tamsulosin
-10-20mm => litho/ureterscopy
-20mm+ => percut nephrolithotomy

Ureteric stones
-lithotripsy, +- ablockers

Infected stone => renal system decompression
-nephrostomy tube/ureteric catheter/ureteric stent

Pain
1st line - NSAID
2nd line - IV paracetamol

Question 3

What is lithotripsy

Answer 3

Shockwave => break stones

But can injure solid organs
Fragments may obstruct ureters
Uncomfortable - needs analgesia during and after

Question 4

Prevention of renal stones

Answer 4

High fluid intake
Avoid carbinated drinks
Limit salt
Potassium citrate
Thiazides