Kidney Stone: Causes, Symptoms, Prevention and Treatment
Normally, urine contains many dissolved substances. At times, some materials may become concentrated in the urine and form solid crystals. These crystals can lead to the development of stones when materials continue to build up around them, much as a pearl is formed in an oyster.
Stones formed in the kidney are called kidney stones. Ureteral stone is a kidney stone that has left the kidney and moved down into the ureter. Urinary bladder stones are either migratory stone from kidney or formed inside the bladder due to stagnation of urine.
The majority of stones contain calcium, with most of it being comprised of a material called calcium oxalate. Other types of stones include substances such as calcium phosphate, uric acid, cystine and struvite.
Although stones occur more frequently in men but the number of women who get them has been increasing over the past 10 years, causing the ratio to change. If a person forms a stone, there is a 50 percent chance that he/she will develop another stone.
Causes of stone formation:
Scientists do not always know what makes stones form. While certain foods may promote stones in susceptible people, researchers do not believe that eating specific items will cause stones in people who are not vulnerable. Yet common risk factors are:
- Less intake of liquids.
- Hot climate.
- Family history of stones, especially in a first-degree relative.
- Diet with high salt content, high animal protein content or oxalate-rich diet such as leafy green vegetables, potato chips, nuts, nut butters or chocolate.
- Medications- Certain diuretics, calcium pills, calcium based antacids
Certain medical conditions – Hyperparathyroidism, chronic diarrhoea, crohn’s disease, post gastric bypass surgery, obesity, Obstruction to urinary passage like in prostate enlargement or stricture disease, Hypercalciuria, Hyperuricosuria, rare hereditary disorders such as cystinuria, primary hyperoxaluria etc.
What are the symptoms of a kidney stone?
The following may be symptoms of kidney stones that need a doctor’s help:
- Extreme pain in your back or side.
- Blood in your urine.
- Fever and chills.
- Urine that smells bad or looks cloudy
- A burning while passing urine.
How are kidney stones diagnosed?
The following mentioned imaging modalities give your doctor information about the size, location and number of stones to determine appropriate treatments.
Ultrasound, X-ray KUB and CT scan
How can kidney stones be prevented?
Unfortunately, kidney stones are a recurrent disease, meaning that if you have one stone you are at risk for another stone event. In general, the lifetime recurrence risk for a stone former is thought to be around 50%. Stone prevention, therefore, is essential.
A good first step for prevention is to drink more liquids and water so as to produce at least two litres of urine in every 24-hour period.
People who form calcium stones used to be told to avoid dairy products and other foods with high calcium content. However, recent studies have shown that restricting calcium may increase stone risk. So, calcium intake should be reduced but not to stop.
High doses of calcium, Vitamin D, or Vitamin C may increase the risk of developing stones, especially in people with a family history of stones. These people need to be careful and should calcium supplementation be needed; calcium citrate is best.
Other general recommendations for stone formers is that they should consume a low sodium and low animal protein diet.
How are kidney stones treated?
Stone size, the number of stones and their location are perhaps the most important factors in deciding the appropriate treatment for a patient with kidney stones. Treatment options are:
- Medical Expulsive Therapy (MET)
- Shock Wave Lithotripsy (ESWL)
- Ureteroscopic stone removal (URS)
- Retrograde Intrarenal Surgery (RIRS)
- Percutaneous Nephrolithotomy (PCNL)
- Laparoscopic Pyelolithotomy/ Nephrolithotomy
- Open Conventional Surgery