Kidney Stones: A Common, Often Painful Complaint
The following is part 1 in a 2-part series. Part 2 will focus on advanced treatments used to break up or remove kidney stones.
Some kidney stone sufferers, especially if they’re female, describe the pain they experience as worse than childbirth.
Before a stone leaves the kidney, you may not even know you have one. But once it starts its journey through the urinary tract, the pain it causes can be severe and debilitating.
Kidney stones are fairly common, says Dr. Luay Alshara, an endourologist and robotic surgeon who serves as an associate professor of urology and an associate attending urologist at Weill Cornell Medicine. In the United States, he says, about 1 in 10 people will experience a stone at some point in their lifetime.
Keep reading for answers to your FAQs about kidney stones, including:
- what they’re made of
- who is at greatest risk for developing them
- how they’re diagnosed
- their symptoms
- managing the pain they cause
- prevention
What are kidney stones?
Kidney stones are hard deposits that form in the kidneys from minerals and salts in the urine. They can vary in size, from as small as a grain of sand to as large as a golf ball.
What are they made of?
Their composition varies, Dr. Alshara says. Here are the most common types:
Calcium stones are the most common type of kidney stone, accounting for roughly 80 percent of cases. Calcium oxalate stones are the most common subtype. These may form when calcium combines with oxalate, a compound found in certain foods such as spinach, nuts and chocolate.
Uric acid stones develop when a person’s urine is too acidic, often due to:
- a diet that includes large amounts of red meat and shellfish
- dehydration
- gout—an inflammatory condition in which uric acid accumulates in the joints
Struvite stones are composed of magnesium ammonium phosphate. They’re usually caused by urinary tract infections (UTIs) that produce ammonia. Struvite stones can grow quite large, and they’re more common in women than in men.
Who is at risk for developing stones?
A combination of lifestyle, medical and genetic factors may heighten a person’s risk of developing kidney stones. Higher-risk individuals include the following:
People with a family or personal history of kidney stones
About half of those who have had one kidney stone will develop another one within 5 to 10 years.
Dehydration
People who don’t drink enough water, live in a hot, dry climate or sweat excessively are at higher risk for developing a stone.
People with certain dietary habits
- high salt intake
- high levels of animal protein
- high oxalate foods
- low calcium intake
People with obesity or metabolic syndrome
- Obesity, diabetes and high blood pressure are linked to an increased risk of stones.
- Insulin resistance, common in type 2 diabetes, can increase calcium in the urine.
Those with certain medical conditions
- UTIs
- Gout
- Hyperparathyroidism (overactive parathyroid glands)
- Inflammatory bowel disease (IBD) or chronic diarrhea
- Cystinuria (a rare genetic disorder)
Sedentary individuals
People who have had gastric bypass surgery
- Weight-loss surgery can alter digestion and increase the absorption of oxalate, raising the risk of calcium oxalate stones.
How do you diagnose kidney stones?
“Kidney stones are often discovered during imaging tests conducted for other reasons,” says Dr. Alshara. “On the other hand, when a patient comes to us with the symptoms we associate with stones, we take a thorough history, perform a physical exam and order blood tests and imaging studies.
“Imaging is the most reliable way to confirm the presence, size and location of a kidney stone,” he continues. “In people with recurrent stones, a full metabolic evaluation is often part of the process as well,” including a 24-hour urine analysis, blood tests and stone analysis.
What are the symptoms of a kidney stone?
Kidney stones can cause a variety of symptoms, depending on their size and location, and whether they’re obstructing your urinary tract. Symptoms can range from mild discomfort to severe, debilitating pain on your side, in the back below your ribs or in your lower abdomen. The pain may radiate to your groin as the stone moves through your urinary tract.
Additional symptoms may include:
- blood in the urine
- urinary symptoms, from pain to frequency, urgency or difficulty urinating
- nausea and vomiting
- cloudy or foul-smelling urine
- fever and chills
- small stones or sand-like particles in the urine
Seek medical attention if:
- medication doesn’t relieve your pain
- you have a fever and chills
- you can’t urinate
- you have persistent nausea and vomiting
How do you manage the pain caused by a stone?
Over-the-counter medications such as ibuprofen (Motrin, Advil), naproxen (Aleve) and acetaminophen (Tylenol) are the first line of defense against pain, Dr. Alshara says. “However, your pain may require stronger, prescribed medications and muscle relaxants to help relax the ureter and ease the passage of a stone.
“We also encourage patients to drink plenty of water to help flush out the urinary system,” he adds. “That may help the stone to pass more quickly. A heating pad can also be applied to the affected side to relax the muscles and relieve pain.”
If your pain is unbearable, you may need to seek emergency care.
Prevention
Preventing kidney stones may involve a combination of dietary changes, lifestyle modifications and, in some cases, medication—especially for people who have had prior episodes.
“The goal is to reduce the risk factors that contribute to stone formation,” Dr. Alshara says.”
Here are his best recommendations:
- Stay hydrated. Aim for at least 10 to 12 cups of water a day to keep your urine diluted.
- Make dietary changes.
- Reduce salt intake.
- Limit foods high in oxalate, such as spinach, rhubarb, nuts, nut butters, chocolate and tea.
- Get enough calcium from food sources, such as dairy products and leafy greens, rather than from supplements.
- Limit animal protein.
- Increase citrate-rich foods. Citrate prevents stone formation by binding to calcium in the urine. Choose citrus fruits or drink lemon water.
- Maintain a healthy weight.
- Exercise regularly.
- Take your medications as prescribed by your doctor.
- Undergo periodic metabolic evaluation—especially if you’ve had prior episodes. Based on the results, your doctor can tailor a prevention plan to address your particular risk factors.
Stay tuned for part 2 of this series, which will provide information about ways to break up or remove “garden variety” as well as complex kidney stones.
Take control of your kidney health. Make an appointment with a specialist by calling 646-962-9600.