Kidney stones are small, crystalline deposits that are formed inside the kidneys. They are formed from waste minerals and acid salts that usually pass out in the urine. Commonly, kidney stones are formed when the urine becomes concentrated, allowing minerals to crystallise and stick together, or when there is a shortage of chemicals that prevent this crystallisation. Stones lodged in the kidney can lead to urinary infections. The smaller stones usually get dislodged from the kidney and travel through the urinary tract and pass out, and this may cause severe pain.
Causes of kidney stones
When the intake of water is inadequate, urine gets concentrated with waste minerals and salts, leading to the formation of stones. The kidney tends to conserves water when fluid intake is less or when much of it is lost through perspiration, especially in hot climes. There are many types of stones, but the most common one is formed when calcium salts get concentrated and crystallise. This may happen when a person consumes a diet rich in calcium or when the body produces an excess of the hormone called parathyroid. People suffering from gout are more likely to suffer from kidney stones. Some drugs that are used to treat HIV infections may also prove to be responsible for the condition.
There may be no symptoms indicating the presence of some stones, especially the small ones, and they may just pass out in the urine without causing any pain. But in case the stones are bigger in size, and especially when they get into the ureter, the person may experience sudden and acute pain in the lower back, groin or abdomen. The pain can be so severe that it may cause nausea, vomiting, or even bleeding. The person may also experience severe pain while passing urine. The pain is relieved when the stone passes out in the urine, but if it gets lodged on the walls of the ureter, it may impede the passage of urine and lead to a swelling of the kidney.
How are stones diagnosed?
A sample of the urine is tested for any traces of blood, crystals or any other evidence of the condition. The urine may also contain particles from the stones that have passed out into the urine. These particles can help the doctors determine the exact composition of the stone i.e. they can determine the minerals or acids of which it is formed. Ordinary or specialised x-rays may also be used to detect the presence of stones in the kidney or the urinary tract. Then there are also blood tests which can determine the density of calcium or uric acid present in the blood. These tests help the doctor decide the mode of treatment.
Preventing the formation of stone
Certain dietary precautions can help in prevention and recurrence of the condition. These include: Drink enough (2-3 litres) of water every day, drink enough water before you sleep to ensure that production of urine continues unhindered at night and the urine does not become concentrated, drink extra fluids in hot weather to compensate adequately for fluids lost in perspiration; depending on the composition of stone you have had, the doctor can suggest appropriate changes in diet.
Treatment of stones
The small stones which remain in the kidney usually do not require any treatment; the doctor may just advise the patient to consume a lot of fluids to help in flushing the stone out in the urine. If the pain is severe, simple painkillers may be prescribed. But if the stone is large, specialised treatment may be necessary. The usual treatment is called lithotripsy in which shock waves are used to pulverise the stone so that it can easily pass through the urine. Lithotomy is another procedure in which an endoscopy is performed to remove the stone. If it is too big, surgery may be required. After treatment, it has been seen that people develop another stone within about seven years, therefore, post-treatment preventive measures become all the more important.