Stones

Low fluid intake, high protein diet, Low calcium diet (Calcium in the diet binds to oxalate and phosphate preventing absorption), Diabetes, Obesity, Rare genetic conditions e.g. Cystinuria

Stones form in the kidney and if they pass out of the kidney into the tube connecting the kidney to the bladder (ureter) pain usually occurs. This is known as “Renal Colic”. The pain is often agonising and comes in waves and patients often cannot get comfortable. Most small stones will pass on their own given some time, but others will not. Many stones may will not cause symptoms if they remain in the kidney but they. Kidney stones may be a cause of blood in the urine and recurrent urine infections.

Most stones are visible on a plain x-ray, known as a KUB. The use of CT scans is becoming more common as it is very good at detecting stones and does not require an injection. We have recently adopted the use of “ultra-low dose” CT scans designed to minimise the dose of radiation received, whilst still being able to visualise stones.

The majority of stones that cause symptoms by passing down the ureter, do not require surgical treatment. 85% of stones less than 4mm will pass spontaneously. Medicines can be given to relieve pain and help with the passage of the stone. Stones within the kidney, can be treated with shockwaves generated by a machine. This is known as Extracorporeal Shock Wave Lithotripsy (ESWL). The patient lies on a couch and the machine is placed against the back. Treatments may last for up to 1 hour, patients may require pain killers during the procedure. The number of treatments required depend on the size, type and number of stones. Some patients require the placement of a ureteric stent before treatment, this is a plastic tube running from the kidney to the bladder placed under a short general anaesthetic.