Kidney stones are solid deposits composed of minerals and salts that develop in the kidneys. This condition is also referred to as renal calculi, urolithiasis ornephrolithiasis.
Factors like diet, obesity, certain medical problems, and some supplements and medicines can lead to the formation of kidney stones. These kidney stones can form anywhere in the urinary tract, from the kidneys to the bladder. Concentrated urine allows crystallization and clumping together of minerals, resulting in the development of stones.
Although passing kidney stones can be extremely painful, they normally don’t lead to permanent damage if detected earlier. Based on the condition, you may only be required to take pain relievers and drink plenty of water in order to pass the stone. However, in situations where the stones are stuck in the urinary tract, linked with a urinary infection, or trigger complications, a surgical procedure may be necessary.
To minimize the possibility of recurring kidney stones, your healthcare provider may suggest preventive measures if you are susceptible to developing them.
By Able Health I Medically reviewed by Dr. Alireza Estedlal
Page last reviewed: February 2024 I Next review due: February 2026
Symptoms
Typically, a kidney stone doesn’t cause any symptoms till it travels within the kidney or enters one of the ureters, the tubes connecting the kidneys and bladder.
If a stone is stuck in the ureters, it could obstruct urine flow. This causes kidney swelling and ureter spasms, which might be painful. Some of the symptoms one may experience at this include:
Intense, sharp pain in the back or side beneath the ribs
Pain radiating to the groin and lower abdomen
Pain that strikes in waves and varies in intensity
A sense of pain or burning when urinating
Other possible symptoms are:
Urine that appears pink, red, or brown
Foul-smelling or cloudy urine
A persistent urge to urinate, unusually frequent urination, or peeing in small amounts
Nausea and vomiting
Fever and chills caused by infection
The pain associated with kidney stones can shift to another location or increase in intensity as the stone goes through the urinary tract.
Causes
Usually, kidney stones don’t have a single, definitive cause, though a number of factors can raise a person’s risk.
The stones develop when the urine has excess crystal-forming substances than it can dilute, including calcium, uric acid, and oxalate. Simultaneously, the urine might not containthe elements that stop these crystals from clumping together. This creates a perfect surrounding for kidney stone formation.
Types of kidney stones
Understanding the kinds of kidney stones makes it easy to identify the causes and can even provide clues on ways of reducing the risk of developing more stones. You should try saving a kidney stone, if possible when passing it to your doctor for analysis.
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Calcium stones: These are the most common type and are often in calcium oxalate form. Oxalate is produced by the liver or absorbed from the diet. High levels of this substance are usually present in certain fruits, vegetables, nuts, and chocolate. Factors like dietary habits, high vitamin D doses, intestinal bypass surgery, and some metabolic conditions can contribute to calcium or oxalate concentration in the urine. Calcium stones can also develop in calcium phosphate form. They are mostly associated with metabolic conditions like renal tubular acidosis or medicines prescribed to address migraines or seizures.
Struvite stones: These develop in response to urinary tract infection and can grow rapidly and enlarge. Struvite stones are sometimes accompanied by a few symptoms or warning signs.
Uric acid stones: These can develop in individuals who lose a lot of fluid due to chronic diarrhea or malabsorption, consume a high-protein diet, are diabetic, or have metabolic syndrome. Some inherited factors can also contribute to uric acid stones.
Cystine stones: These affect those with a genetic condition known as cystinuria, which prompts the kidneys to expel excessive amounts of a particular amino acid.
Risk factors
These risk factors are likely to contribute to kidney stone formation:
Family or personal history: If kidney stones run in your family, then you are at a high risk of developing them as well. Having had one or more kidney stones also increases the likelihood of more stones.
Dehydration: Insufficient intake of water can raise thepossibility of kidney stones. Individuals living in warm, dry environments or who sweat excessively are at greater risk.
Specific diets: Diets rich in protein, sodium (or salt), and sugar can increase the likelihood of certain kinds of kidney stones. A high-sodium diet is particularly risky since it raises the level of calcium the kidneys have to filter. As a result, it significantly elevates the possibility of stone formation.
Obesity: A higher body mass index (BMI), big waist size, and adding weight are all associated with a greater risk of developing kidney stones.
Digestive diseases and surgery: Conditions such as inflammatory bowel disease and chronic diarrhea, as well as gastric bypass surgery, can alter digestion and affect calcium and water absorption. This increases the concentration of stone-forming substances in the urine.
Some health conditions: Disorders like renal tubular acidosis, hyperparathyroidism, cystinuria, and recurrent urinary tract infections can contribute to the formation of kidney stones.
Certain supplements and medications: Excessive use of vitamin C, laxatives, dietary supplements, calcium-based antacids, and specific drugs for treating migraines or depression may increase the likelihood of developing kidney stones.
Diagnosis
If a kidney stone is suspected, the medical provider will conduct the following tests and procedures:
Blood tests: These can show high levels of calcium or uric acid in the bloodstream. The test outcomes also help keep track of kidney health and identify other potential medical disorders.
Urine tests: A 24-hour urine collection test can reveal if you are expelling excessive stone-forming minerals or insufficient stone-preventing elements. The doctor might order two urine collections for consecutive days for this test.
Imaging: Imaging tests, such as high-speed or dual-energy computerized tomography (CT), can reveal kidney stones in your urinary tract, including very small ones. Doctors do not frequently use abdominal X-rays since they may not detect the tiny stones. On the other hand, an ultrasound, which is a non-invasive, fast, and easy test, is another option for diagnosing kidney stones.
Analysis of passed stones: The doctor can ask you to pee through a filter so as to catch any stones passed. Lab analysis of these stones helps determine their composition. This helps determine the underlying cause of the condition and develop an effective plan to prevent future recurrence.
Treatment
Kidney stones treatment often depends on the type of stone and its underlying cause.
Small stones with minimal symptoms
Most cases of small kidney stones do not need invasive treatment. This is because with these remedies, you can easily pass a tiny stone:
Drinking water:8 to 3.6 litres of water daily helps keep the urine diluted, which can lower the chances of stone formation. Unless advised otherwise by your doctor, drink plenty of fluids, preferably water, to have clear or almost clear urine.
Pain relievers: It might be uncomfortable to pass a small stone. Therefore, to alleviate mild discomfort, the doctor may suggest painkillers like ibuprofen or naproxen sodium.
Medical therapy: The provider may prescribe medication to assist in passing the kidney stone. These drugs, called alpha blockers, help relax the muscles in the ureter, allowing the stone to pass faster and with minimal discomfort. Types of alpha blockers are tamsulosin and a combination of dutasteride and tamsulosin medicines.
Large stones and those that cause symptoms
For kidney stones that are overly big to pass naturally or those causing kidney damage, bleeding, or persistent urinary tract infections, more extensive therapies may be necessary. The procedures that can be recommended are:
Using sound waves to break up stones: Based on the location and size of some kidney stones, the doctor can suggest extracorporeal shock wave lithotripsy (ESWL). This procedure utilizes sound waves to generate robust vibrations (or shock waves), breaking the stones into small pieces that could pass into the urine. ESWL lasts between 45 to 60 minutes and can be accompanied by moderate pain; hence, sedation or light anaesthesia is often used to ensure comfort during the treatment. The procedure can result in blood in the urine, bleeding near the kidney and surrounding organs, bruising on the back or abdomen, and pain as the stone pieces pass over the urinary tract.
Surgery to remove very large stones in the kidney: Percutaneous nephrolithotomy is a surgical procedure done to remove a kidney stone with small telescopes and tools placed through a tiny incision in the back. General anaesthesia is administered during the treatment, and a hospital stay of 1 to 2 days is usually required as you recover. Doctors often suggest this surgery when ESWL isn’t effective.
Using a scope to remove stones: The doctor can insert a thin, illuminated tube called a ureteroscope that is attached to a small camera into the ureter via the urethra and bladder. After locating the stone with the help of the camera, specialized equipment is used to trap it or break it down into fragments that will be passed in the urine. A small tube (stent) may be placed in the ureter to alleviate swelling and promote recovery. This procedure might require general or local anaesthesia to ensure comfort.
Parathyroid gland surgery: Overactive parathyroid glands situated on the four thyroid gland corners just under the Adam’s apple cause particular calcium phosphate stones. Production of excess parathyroid hormone (hyperparathyroidism) in these glands results in too high calcium levels, leading to kidney stone formation.
In some cases, hyperparathyroidism may result from a small, noncancerous tumor on one of the parathyroid glands or another disorder causing overproduction of parathyroid hormone. Taking out the tumor from the glands prevents kidney stone formation. Alternatively, medical providers can suggest treating the underlying condition that prompts the parathyroid gland to produce excess hormones.
Prevention
Preventing kidney stones can involve a combination of medicationsand lifestyle adjustments.
Lifestyle changes
By taking these measures, you can effectively lower your risk of developing kidney stones:
Drinking water throughout the day: Taking sufficient fluids to pass at least 2 litres of urine daily is advisable, especially for those who have had kidney stones. Your provider can also recommend measuring your urine output to ensure you are drinking plenty of water. For people living in a hot, dry environment or those who regularly exercise, it’s important to take more fluids so as to produce adequate urine. Having lighter and clearer urine usually indicates sufficient water intake.
Consuming fewer oxalate-rich foods: For those who are prone to calcium oxalate stones, the doctor may suggest limiting foods full of oxalates. Examples are rhubarb, okra, beets, spinach, sweet potatoes, Swiss chard, nuts, chocolate, tea, soy products, and black pepper.
Choosing a diet low in salt and animal protein: Lowering salt intake and opting for nonanimal protein sources, including legumes, is essential. You can also use sodium substitutes like Mrs. Dash.
Keep on consuming calcium-rich foods, but be cautious with calcium supplements: The presence of calcium in food doesn’t influence the likelihood of kidney stone formation. You should, therefore, continue consuming a calcium-rich diet unless advised otherwise by your doctor.
Before using calcium supplements, it is important to consult your doctor since they have been associated with a higher possibility of kidney stones. However, you can lower the risk by taking these supplements with food. For some people, a low-calcium diet can increase the formation of stones.
Find a professional dietician to help you create a meal plan that lowers the likelihood of kidney stone formation by asking your medical provider for referrals.
Living With
Can I lead a normal life with kidney stones?
Yes, kidney stones should not significantly disrupt your daily activities or lower your quality of life. You can pass them when urinating, and with various treatment options available, kidney stones are not a permanent condition.
Do kidney stones cause kidney disease? Having a history of kidney stones increases your risk of developing more stones as well as chronic kidney disease.
Are kidney stones life-threatening? No, kidney stones are not deadly.
When should I visit my doctor? Visit your doctor right away if you experience symptoms of kidney stones. It’s important to know the location and size of the stone, if you have it, in order to receive proper treatment and avoid complications.
When should I go to the ER? You should head to the ER if the discomfort becomes unbearable. The doctor may prescribe some medications to relieve pain, and associated nausea or vomiting.
What questions should I ask my doctor?
Consider asking your provider the following questions during your visit:
Do I have a kidney stone, or could there be another cause for my symptoms?
What kind of kidney stone do I have?
What is the size of my kidney stone?
What is the location of my kidney stone?
How many kidney stones do I have?
Do I require treatment, or will I naturally pass the kidney stone?
Should I undergo a kidney disease test?
What dietary changes should I make?
What procedure is appropriate for me to remove the stones?
Preparing for your appointment
Usually, smaller kidney stones that do not obstruct the kidney or lead to additional problems can be effectively addressed by the family physician. However, for a large stone causing intense pain or kidney problems, the doctor can recommend getting help from a specialist in urinary tract conditions (nephrologist or urologist).
