What Are Kidney Stones?
Kidney stones are solid masses made of crystals. They originate in the kidneys and can develop anywhere along the urinary tract. The urinary tract includes the kidneys, ureters, bladder, and urethra. Kidney stones can be very painful.
Causes of Kidney Stones
Kidney stones often have no single or definite cause; several factors may increase the risk of formation of kidney stones.
Kidney stones formation happens when more crystal-forming substances — such as calcium, oxalate and uric acid are present in the urine— than the fluid in the urine can dilute. At the same time, the urine may lack substances that prevent crystals from sticking together, which creates an environment for kidney stones to form.
Types of Kidney Stones
The different types of kidney stones include:
Calcium stones are the most common types of stones. They can be made of calcium oxalate (most common), phosphate, or maleate. Oxalate is a naturally occurring substance found in food. The liver also produces oxalate. Eating less oxalate-rich foods can help in reduction of the risk of developing calcium kidney stones. High-oxalate foods include potato chips, peanuts, chocolate, beets, and spinach.
Men are more prone to this type of kidney stone than women. These stones can occur to those who are going through chemotherapy. This type of stone is developed when urine is too acidic. Purine rich diet can increase urine’s acidic level. Purine is a colorless substance found in animal proteins, such as fish, shellfish, and meats.
Women are more prone to this type of kidney stones than men and are formed in response to an infection in the kidney. These stones can grow quickly and become quite large and can cause urinary obstruction. Treating an already existing infection can prevent the development of these stones.
Cystine stones rarely occur. Genetic disorder cystinuria in men and women are the main cause of these stones. This causes the kidneys to excrete too much of certain amino acids (cystinuria).
A kidney stone may not cause symptoms until it moves around within the kidney or passes into the urethra — the tube connecting the kidney and bladder. At that point, people may experience these signs and symptoms:
- Severe pain in the side and back, below the ribs
- Pain that spreads to the lower abdomen and groin
- Pain while urinating
- Cloudy urine
- Urine smelling differently than normal
- An urge to urinate more often than usual
- Pain that becomes so severe you can’t sit, stand, or lie down comfortably
- Blood in your urine
- Difficulty urinating
Factors that increase the risk of developing kidney stones include:
- Family or personal history. If someone in your family has kidney stones, you're more likely to develop stones, too. And if you've already had one or more kidney stones, you're at increased risk of developing another.
- Dehydration. Not drinking enough water each day can increase your risk of kidney stones. People who live in warm climates and those who sweat a lot may be at higher risk than others.
- Certain diets. Eating a diet that's high in protein, sodium and sugar may increase your risk of some types of kidney stones. This is especially true with a high-sodium diet. Too much sodium in your diet increases the amount of calcium your kidneys must filter and significantly increases your risk of kidney stones.
- Being obese. High body mass index (BMI), large waist size and weight gain have been linked to an increased risk of kidney stones.
- Digestive diseases and surgery. Gastric bypass surgery, inflammatory bowel disease or chronic diarrhoea can cause changes in the digestive process that affect your absorption of calcium and water, increasing the levels of stone-forming substances in your urine.
- Other medical conditions. Diseases and conditions that may increase your risk of kidney stones include renal tubular acidosis, cystinuria, hyperparathyroidism, certain medications and some urinary tract infections.
If stone size is less than 5-6 mm, it can pass spontaneously. Meanwhile if symptomatic, the analgesic or sometime antibiotics are required.
There is no role of intravenous fluid (flush therapy) unless patient is unable to take fluid orally because of vomiting.
If stone size is less than 1.5 cm in kidney or upper ureter, Lithotripsy can be done. Shock waves are used to fragment the stone which passes by natural method through urinary tract.
This is the non-invasive method for the treatment of urinary stone.
It is endoscopic method to remove stones from the ureter. It is done under regional/ general anesthesia and requires one to two days of hospitalization.
Percutaneous Nephrolithotomy (PCNL)
If kidney stone is bigger than 2 cm of size, usually it requires removal by PCNL. Here, an endoscope is used after making a tract from the back of the patient for stone removal. Usually, it requires fragmentation by means of Laser/ Pneumatic Lithotripter.
Retrograde Intrarenal Surgery (RIRS)
A small flexible uretero-renoscope passed through urethra up-to kidney and stones are fragmented with the help of Laser and removed. Usually up-to 2 cm size stones can be removed by this technique. Main advantage of this procedure is that it does not require kidney puncture and therefore chances if bleeding is less, patients hospital stay is reduced and is relatively more safe.