Kidney Stones: Causes, Symptoms and Treatments
Kidney stones usually comprised of a compound called calcium oxalate, are the result of an accumulation of dissolved minerals on the inner lining of the kidneys. These deposits can grow to the size of a golf ball while maintaining a sharp, crystalline structure.
The kidney stones may be small and pass unnoticed out of the urinary tract, but they may also cause extreme pain upon exiting.
Kidney stones that remain inside the body can lead to many conditions, including severe pain and ureter (the tube connecting the kidney and bladder) blockage that obstructs the path urine uses to leave the body.
Scientists at the Mayo Clinic, Rochester, USA, say that people with kidney stones are at a significantly higher risk of developing chronic kidney disease.
Causes of kidney stones
Kidney stones can vary in size. Some have been known to become as big as golf balls.
The leading cause of kidney stones is a lack of water. Stones commonly have been found in those that drink less than the recommended eight to ten glasses of water a day. When there is not enough water to dilute the uric acid (component of urine), the pH level within the kidneys drops and becomes more acidic. An excessively acidic environment in the kidneys is conducive to the formation of kidney stones.
Medical conditions such as Crohn's disease, urinary tract infections, renal tubular acidosis, hyperparathyroidism, medullary sponge kidney, and Dent's disease have been known to lead to kidney stones. It also has been suggested that water fluoridation - the addition of fluoride to drinking water - is responsible for some cases of kidney stones.
Vitamin D and Calcium supplements linked to kidney stone risk
A study carried out by scientists at Creighton University Medical Center suggested that calcium and vitamin D supplements could increase the risk of developing kidney stones because they raise levels of calcium in the blood and urine.
Head researcher, J. Christopher Gallagher, M.D., explained that perhaps using vitamin D and calcium supplements is not as benign as people had thought. He advised people not to exceed the guidelines for these supplements of 800 international units of vitamin D, and 800-1,200 milligrams of calcium per day (according to the Institute of Medicine).
When asked which of the two supplements might be raising kidney stone risk, Dr. Gallagher said:
"It is not clear whether it is the extra calcium, the vitamin D or both together that cause these problems.However, it is possible that long-term use of supplements causes hypercalciuria and hypercalcemia, and this can contribute to kidney stones. For these reasons, it is important to monitor blood and urine calcium levels in people who take these supplements on a long-term basis. This is rarely done in clinical practice."
Who gets kidney stones?
Kidney stones are twice as common among males as females. Most people who experience kidney stones do so between the ages of 30 and 50. A family history of kidney stones also increases one's chances of developing them at some point in life. Similarly, a previous kidney stone occurrence increases the risk that a person will develop subsequent stones in the future if preventative action is not taken.
Certain medications can increase the risks of developing kidney stones. Scientists found that opiramate (Topamax), a drug commonly prescribed to treat seizures and migraine headaches, can increase the propensity of calcium phosphate kidney stone.
The more overweight a person is the more at risk he or she is for forming uric acid kidney stones, a study found.
Additional risk factors for kidney stones include diets that are high in protein and sodium but low in calcium, a sedentary lifestyle,obesity, high blood pressure, and conditions that affect how calcium is absorbed in the body such as gastric bypass surgery, inflammatory bowel disease, and chronic diarrhea.
A study indicated that kidney stones among children are on the rise.
Symptoms of kidney stones
A kidney stone usually remains symptomless until it moves into the ureter. When symptoms of kidney stones become apparent, they commonly include:
- Severe pain in the groin and/or side
- Blood in urine
- Vomiting and nausea
- White blood cells or pus in the urine
- Reduced amount of excreted urine excreted
- Burning sensation during urination
- Persistent urge to urinate
- Fever and chills if there is an infection
Diagnosis of kidney stones
Several different tests can verify the existence of a kidney stone. A physical examination may reveal colicky pain (in the groin) and pain in the lower back by the kidneys - often warning signs of the condition. An analysis of the urine will indicate whether or not there is blood in the urine and if there is a subsequent infection. Blood tests can be done to identify complications that may accompany a kidney stone and check the validity of the diagnosis.A CT scan of the abdomen is the most thorough way to test for kidney stones. A CT scan will ascertain the state of the ureter, bladder, and kidneys, whether or not a stone exists, the kidney stone's exact size and location, whether or not a blockage exists, and the state of the other adjacent organs such as the appendix, aorta, and pancreas. Pregnant women may receive an ultrasound rather than a CT scan in order to avoid unnecessary radiation.Once a patient is diagnosed with a kidney stone, simple x-rays will be used to track the stone's progress through the excretory system.Treatments for kidney stones
Treating kidney stones primarily is focused on symptom management; passing a stone can be very painful. If a person has a history of kidney stones, home treatment may be suitable. A person who has never passed a kidney stone should seek the help of a medical professional.If hospital treatment is sought, personnel will hydrate the patient via an intravenous tube and administer anti-inflammatory medication. Narcotics are often used as medication in an attempt to make the pain of passing the stone tolerable. Anti-emetic medication can treat a patient suffering from nausea and vomiting.
Lithotripsy involves sending a shockwave into the kidney stone to break it into smaller pieces.In some cases, a urologist can perform a shock wave therapy called lithotripsy - a treatment that will break the kidney stone into smaller pieces and allow it to pass. A study indicated that shock wave therapy for kidney stones may be linked to an increased risk of diabetes.Patients with large stones located in regions that do not allow for lithotripsy may receive surgical procedures such as percutaneous nephrolithotomy (removal of the stone through an incision in the back) or ureteroscopic stone removal (removal of the stone through a thin tube into the urethra).Prevention of kidney stones
For individuals in good health, preventing kidney stones can be as easy as staying hydrated. Diluting the urine with water keeps the minerals from concentrating and forming stones. When one's urine is clear, rather than yellow colored, the chance of stone formation is reduced. Doctors may also prescribe medicines to prevent certain types of stones for individuals who are at higher risk.If you’ve had a kidney stone, your doctor will probably advise you to increase the amount of water you drink, to reduce your risk of getting another one. You should be drinking enough fluid to make your urine colourless rather than yellow or brown.If you’ve had a calcium stone, your doctor may also advise you to do the following.- Cut down on salt to less than 3g of salt a day – don’t add it to your food and don’t eat processed foods.
- Cut down on foods that have high levels of oxalate – such as chocolate, tea, rhubarb, spinach, nuts and strawberries.
- Eat less meat, fish and poultry. Liver, kidneys, herrings with skin, sardines, anchovies and poultry skin increase the amount of uric acid in your urine.
- Don’t take vitamin C supplements of more than 500 to 1000mg per day because vitamin C forms oxalate in the body. You should also steer clear of vitamin D preparations, including fish oils and multivitamins. These can increase how much calcium you absorb.
Depending on the types of kidney stone you get, your GP may prescribe various medicines to help prevent further stones
A study published in 2006 suggests that a daily glass of orange juice can help prevent the recurrence of kidney stones better than other citrus fruit juices such as lemonade.A different study published in 2004 suggests that if you are prone to kidney stones you should watch your caffeine intake.
