Treatment of Urinary Stones

The initial treatment is directed at the complications i.e. pain and infection control. Pain is usually successfully relieved by injectables painkillers and suppository Voltaren in the first instance, and maintained by oral painkillers. Any suspected infection will have to be controlled by antibiotics, and in severe cases, with the insertion of a tube into the affected kidney to drain the infected urine.

Not all urinary stones need to be treated. Upto 90% of stones less than 4mm; and 50% to 60% of stones 4-6mm can pass out on their own (with rates increasing to 80% with a-blockers) provided the pain is adequately controlled and there is no significant obstruction and infection. However, surgical treatment is recommended for stones greater than 7mm; and is advisable for any stones in pilots, drivers and workers who need to climb scaffoldings.

There are various types of surgical treatment. They include extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL) ureteroscopic lithotripsy (URS lithotripsy) and open surgery. The choice of treatment would depend on the site and size of the stone, urgency of clearance of the stone, degree of kidney damage and type of stone. The choice is best discussed with your urologist.

ESWL – shockwaves generated outside the body, passes through the body and focused onto the stone. The stone breaks up and the fragments are passed out with the urine. No anaesthesia is required and only painkillers are given. After treatment, urine may be blood-stained for 24-48 hours. The patient is usually able to go home 2 hours after the treatment. Depending on the composition, size and position of the stone, and the type of machine used, the success rate varies from 70 to 90%. More than 1 treatment may be needed in 10 to 30% of stones. This procedure is usually recommended for kidney stones <2cm and upper ureteric stones.

PCNL is preferred for kidney stones more than 2 cm in diameter and residing in the lower part of the kidney,. This procedure requires anaesthesia. A small skin puncture is made and enlarged to insert a scope into the kidney. The stone is then located and fragmented under direct vision. The fragments are then removed.

URS lithotripsy is usually recommended for lower ureteric stones. In this procedure, a scope is inserted into the ureter via the urethra and bladder (hence no incision required) to reach the stone. The stone is then fragmented using laser, ultrasound or pneumatic shockwaves. The fragments are then removed. The success rate of this procedure for
 lower ureteric stones is in excess of 90%. It is also indicated for ureteric stones in the upper ureter causing severe obstruction where immediate clearance is important.

Open surgery is rarely required except in cases where the kidney is severely damaged or infected and hence best removed. Somelarge kidney stones may still be best treated by this method especially if it is important to eompletely remove the stone in one setting.

 Chemical dissolution (with oral medication) can be effective for uncomplicated uric acid stones. By alkalinising the urine with baking soda or potassium citrate, uric acid stones can be dissolved because it is 40 times more soluble in alkaline than in acidic urine. However, this treatment may take a long time; up to months. Hence it is not suitable for large uric acid stones.