Stones can occur in any part of the urinary tract and are named after the area in which they are located e.g. renal stones (stones in the kidney). They can also be described by what they are composed of. The most common are calcium stones.
The urinary tract
The ‘urinary tract’ is the name given to all parts of the system that produce and transport urine. This begins with the kidneys, which produce urine, which then passes through tubes called ureters to the bladder. The bladder is where urine is stored. Urine from the bladder is then emptied along a tube called the urethra.
The kidneys are two organs that filter waste and fluid from the blood that passes through them to produce urine. ‘Renal’ refers to the kidney.
The ureters are the tubes that connect the kidneys to the bladder.
What are the symptoms of stones?
- Pain in the loin or side of the abdomen. This may radiate to the groin area.
- Blood in the urine. This may be visible to the eye or picked up on urine dipstick test.
- Urine infections. Symptoms of infection include high temperature, pain in the bladder or kidney area or on passing urine, and a need to pass urine frequently.
What are the risk factors for forming stones?
- Inadequate hydration.
- Previous history of stones.
- A family history of stones.
- Certain drugs or medical conditions that result in altered urine volume or altered urine pH levels.
- Middle age, overweight, male.
What investigations may I need?
Investigations may include blood tests, x-rays, CT or ultrasound scans.
What are the treatments?
Treatment options depend on the location and size of the stone and also whether it is causing any symptoms. Small stones in the kidney that are not causing symptoms do not necessarily need treatment. These can be monitored. Some stones may pass spontaneously without treatment.
- Lithotripsy. Shockwave therapy to break the stone into small fragments that can then be passed. This is an outpatient procedure.
- Ureteroscopy. Under anaesthetic, a small telescope is passed through the urethra and bladder into the ureter or kidney to allow the stone to be fragmented (using laser technology) and removed.
- Percutaneous nephrolithotomy (PCNL). Under anaesthetic, a telescope is passed via the skin into the kidney to allow the stone to be fragmented and removed. This is more commonly used for larger stones.