Very painful but usually pass by themselves
Kidney stones form when the urine has a high concentration of waste products such as calcium, ammonia, uric acid and cysteine. The stones form in the kidneys and whilst they may remain there, they often travel down the tube (ureter) that drains urine from the kidney to the bladder. If a stone passes into the ureter it can get stuck and be extremely painful (renal or ureteric colic).
Who gets them?
Kidney stones are quite common, especially amongst people between 30 and 60 years of age. One in ten women and three in twenty men get kidney stones at some point in their life.
Some medical conditions cause unusually high blood concentrations of the substances that form stones. People with high blood pressure and gout and those who suffer from repeated urine infections are also more likely to develop stones, as well as those with pre-existing kidney disease such as cysts or scarring from previous infections. Dehydration is a key factor and people who live in hot climates tend to get kidney stones more often.
Certain medicines also predispose to stone formation including aspirin, antacids, diuretics, some antibiotics and some medicines used for treating epilepsy & HIV infection.
Very small kidney stones often cause no symptoms and the stone passes through the bladder and out in the urine without the patient noticing.
However, larger stones usually cause pain as the muscular wall of the ureter tries to squeeze it down towards the bladder. The pain is usually severe, starts very suddenly, comes and goes in waves and can be felt at the back under the ribs spreading down and round into the groin.
Sometimes stones can cause bleeding and the urine may contain frank blood or just have a pink tinge. Other symptoms include feeling or being sick, pain when passing urine, feeling the need to urinate more often, and feeling shaky and feverish, especially if a kidney infection develops.
If you get renal or ureteric colic, a sample of urine will be taken and tested for the presence of blood and infection, together with blood tests to look at how the kidneys are working and for signs of infection and inflammation.
A CT scan or ultrasound will also be done to look for the stone. These tests also show whether the stone has got stuck and whether or not urine is draining freely – if not, the kidney can swell up behind it.
Prevention and treatment
Most stones under 4mm pass eventually and any pain is treated with pain relief. You may also need medicines to reduce nausea or vomiting. You’ll need to drink plenty of fluids to keep the kidneys working normally and to flush out the stone(s).
If a kidney stone doesn’t pass on its own, it needs to be broken up into smaller pieces (which are small enough to pass naturally) or you’ll need a procedure to remove them. This can be done with shock waves or inserting a very fine tube up to the kidney.
The most effective way of preventing stones forming is to drink plenty of fluids. If you have certain conditions, or have had particular types of stone before, you may be advised to restrict certain types of food but you should get advice about this from a doctor to ensure your diet is appropriate. Some people also need long term treatment for specific conditions that predispose to stones such as people with gout or recurrent urine infections.
Contact Bluezone if:
- You have pain in your back spreading down and around to your groin.
- You notice blood in your urine
- It’s painful to pass urine or you’re going more frequently than normal.