composition of urinary tract stones

Last reviewed 01/2018

The various types of renal stone are listed below:

  • calcium oxalate stones:
    • 80% of all stones
    • radio-opaque
    • solitary, hard and white
    • require alkaline urine

  • triple phosphate stones:
    • 10% of all stones
    • radio-opaque
    • may fill the calyceal system (Staghorn calculi)
    • require very alkaline urine, often with urea-splitting bacteria

  • uric acid stones:
    • 5-10% of all stones
    • radio-lucent
    • multiple
    • associated with gout and other causes of urate nephropathy e.g. chemotherapy for leukaemia

  • cystine stones:
    • rare
    • radio-opaque
    • usually seen in patients with cystinuria