Kidney stones: Symptoms, treatment and prevention
What are kidney stones?
Kidney stones are a build-up of crystals in the kidneys that form hard lumps, which in turn can cause pain and problems in the urinary system.
Kidney stones are fairly common and affect around 15% of men and 10% of women during their lives.
Small stones can be as tiny as a grain of sand and may remain in the kidneys without causing any symptoms. Pain can occur as stones get bigger.
Some stones may be as big as a golf ball. If the stone moves around or gets stuck in the kidney or ureter, this can cause pain.
Kidney stones can also cause infections.
Problems with kidney stones are most common between the ages of 30 and 60.
Types of kidney stones
Kidney stones are classified by the substance that forms them. The main types of kidney stones are:
- Calcium stones
- Struvite stones
- Uric acid stones
- Cystine stones
Depending on the type, stones may be harder or softer, bigger or smaller, and more or less likely to cause pain or infections, and the treatment may differ.
Although the stone is in the kidney or ureter, pain from the stone or any infection is usually felt elsewhere.
The symptoms of kidney stones include:
Seek urgent medical attention if there's fever, quickly worsening pain with or without chills or shaking.
What causes kidney stones?
A diagnosis of kidney stones will be based on the symptoms, medical history and tests, including:
- Urine tests
- Testing for stone type of any stones or fragments passed in urine, this can be collected in an old pair of tights or in a piece of gauze
- Blood tests for kidney problems
- CT scan
- Ultrasound scan
- Intravenous urogram (IVU), intravenous pyelogram (IVP), enhanced X-rays taken after special dye is injected into the arm
Treatment may not be needed, especially if stones are small enough to pass in the urine.
Home care for kidney stones involves drinking plenty of water to keep urine clear rather than being darker.
Medical treatments for kidney stones may require admission to hospital.
Treatments will depend on individual circumstances and the results of tests, and include:
- Pain relief, often injected
- Anti-nausea medication
- Extracorporeal shock wave lithotripsy (ESWL) to break up stones by blasting them with high frequency sound waves
- Ureteroscopy, using an instrument that's passed through the urethra, then into the bladder and on into the ureter, to remove lodged stones
- Percutaneous nephrolithotomy (PCNL), using an instrument passed through an incision to break up stones
- Open surgical operation to reach the kidneys and ureter to remove stones.
Complications of procedures to remove stones include infections ( sepsis), ureter blockage from fragments of stone, ureter damage, further pain and bleeding.