Kidney Stones Overview
Kidney stones are small. They can be as tiny as a grain of salt or as big as a corn kernel. You may not feel anything and never realize you even had one.
But other times, you’ll know about it. That’s because flushing one out of your body as you pee can hurt, sometimes enormously.
That pain you feel as you pass a stone is the main sign that you might be taking in too much minerals and not enough fluids. That imbalance is one reason these pebble-like objects might form. The stones can be brown or yellow, and smooth or rough.
What Does a Kidney Stone Feel Like?
When you have a kidney stone, you may not have any symptoms — that is, until the stone starts to stir.
It can move around within your kidney or into your ureter, the tube that connects your kidney to your bladder.
Symptoms can vary and can be mild or severe. The most common one is pain. You may feel it:
- In your side or back, below the ribs — and the pain can be very intense
- In your groin and lower abdomen
- Come and go and get better or worse
- As you pee — and you might have to go more often than usual
The pain can shift around in your body, from your belly or back down to your groin. This means the stone is making its way from your kidney through the ureter and closer to your bladder.
When this happens, you are more likely to feel a burning when you pee or have more urges to go.
Sometimes, you can spot the stones after they exit.
Do Bigger Stones Hurt More?
Surprisingly, the size of your kidney stone doesn’t match the degree of pain.
Sometimes smaller stones can hurt the worst, while big stones might just give you a dull ache.
A kidney stone can be as tiny as a grain of sand, and you can pass it in your pee without ever knowing. But a bigger one can block your urine flow and hurt a lot. Some people say the pain can be worse than childbirth.
These hard nuggets form when minerals in your pee clump together. That can happen from many things, like what you eat and certain medications. If you or someone in your family has had a kidney stone, you’re more likely to have one in the future.
Lack of Water
You need to make enough urine to dilute the things that can turn into stones. If you don’t drink enough or sweat too much, your pee may look dark. It should be pale yellow or clear.
If you’ve had a stone before, you should make about 8 cups of urine a day. So aim to down about 10 cups daily, since you lose some fluids through sweat and breathing. Swap a glass of water for a citrus drink. The citrate in lemonade or orange juice can block stones from forming.
Diet
What you eat can play a big role in whether you get one of these stones.
The most common type of kidney stone happens when calcium and oxalate stick together when your kidneys make urine. Oxalate is a chemical that’s in many healthy foods and vegetables. Your doctor may tell you to limit high-oxalate foods if you’ve had this type of stone before. Examples include:
- Spinach
- Rhubarb
- Grits
- Bran cereal
You may have heard that drinking milk can bring on kidney stones. That’s not true. If you eat or drink calcium-rich foods (like milk and cheese) and foods with oxalate at the same time, it helps your body better handle the oxalate. That’s because the two tend to bind in the gut instead of in the kidneys, where a stone can form.
Sodium
You mainly get this through table salt. It can raise your chances of getting several types of kidney stones. So watch out for salty snacks, canned foods, packaged meats, and other processed foods.
Animal protein
Another kind of kidney stone forms when your pee is too acidic. Red meat and shellfish can make uric acid in your body rise. This can collect in the joints and cause gout or go to your kidneys and make a stone. More importantly, animal protein raises your urine’s calcium level and lowers the amount of citrate, both of which encourage stones.
Gut Problems
Stones are the most common kidney problem in people with inflammatory bowel disease like Crohn’s disease and ulcerative colitis. Bowel problems can give you diarrhea, so you make less pee. Your body may absorb extra oxalate from the intestine, so more gets in your urine.
Obesity
You’re almost twice as likely to get a kidney stone if you’re obese. That’s when your body mass index is 30 or above. If you’re 5 feet 10 inches tall, obesity starts at 210 pounds.
Weight loss surgery can help you shed pounds and improve your health. But the surgery itself can cause stones. Studies suggest that people who have the most common weight loss operation, the Roux-en-Y gastric bypass, are much more likely to get stones.
Other Medical Conditions
Many diseases can encourage one or more types of kidney stones to form.
Certain genetic diseases
One example is medullary sponge kidney, a birth defect that causes cysts to form in the kidneys.
Type 2 diabetes
It can make your urine more acidic, which encourages stones.
Gout
This condition makes uric acid build up in the blood and form crystals in the joints and the kidneys. The kidney stones can become large and very painful.
Parathyroidism
Your parathyroid glands can pump out too much hormones, which raises calcium levels in your blood.
Renal tubular acidosis
This kidney problem causes too much acid to build up in the body.
Medications
Some that can cause stones include:
- Certain antibiotics, including ciprofloxacin and sulfa antibiotics
- Some drugs to treat HIV and AIDS
- Certain diuretics used to treat high blood pressure. But some thiazide-type diuretics actually help prevent stones.
Kidney stones usually pass on their own without causing any long-term problems. If they don’t, or if you’re in a lot of pain, your doctor can break up or remove the crystals.
Your treatment depends on where and how big your stone is and what symptoms you have.
First, You Wait
If your stone doesn’t bother you, your doctor may suggest you wait 2-4 weeks for it to pass on its own. She may tell you to drink extra water to help flush it out of your body.
She may ask you to catch the stone in a strainer when you pee. A lab can test it for minerals to see if medication might prevent more stones.
Medicines
If you’re in discomfort, you can manage your symptoms while you wait for the stone to exit.
Over-the-counter pain relievers such as acetaminophen or ibuprofen can help. You might also need a drug to ease nausea.
Prescription drugs can help hurry the stone along:
Calcium channel blockers and alpha-blockers: These relax your ureter, the tube through which pee passes from your kidney to your bladder. A wider ureter will help the stone move more quickly.
Potassium citrate or sodium citrate: If your stone is made from uric acid, the doctor might give you one of these solutions to dissolve it.
Surgery
Sometimes, a stone is too big come out by itself. Your doctor may have to break it up or remove it. She also may do that if you are:
- In a lot of pain
- Have an infection
- Unable to pee because the stone is blocking the flow
Your doctor can choose from several procedures.
Shock wave lithotripsy (SWL). This is the most common treatment in the U.S. It works best for small or medium stones. Your doctor aims high-energy sound waves to break up the kidney stone into little pieces. The shock waves come from outside the body, which is why the procedure sometimes is called extracorporeal SWL.
You will get pain-numbing medicine beforehand, and you usually can go home on the same day.
Ureteroscopy
Your doctor inserts a thin, flexible scope through your ureter and bladder to reach the stone. If the stone is small, she can use a basket to remove it. If the stone is larger, a laser passed through the scope can break it up.
Percutaneous nephrolithotomy or percutaneous nephrolithotripsy. These similar procedures are an option if your stone is large or if other procedures fail to break them down enough. Your doctor uses a thin tube to reach the stone and them removes (nephrolithotomy) or breaks (nephrolithotripsy) it.
You will be given drugs so you won’t be awake or feel pain. You’ll likely have to stay in the hospital for 1-2 days.
Open surgery
This might be an option if your stone is very oversized or your doctor can’t take it out with other treatments. You’ll be sedated and not awake. Your surgeon cuts through your side to reach the kidney, then takes the stone out through the opening.
You may need to stay in the hospital for a few days. It can take 4-6 weeks for you to fully recover.
Your surgeon usually will ask a lab to identify the type of stone, so you might be able to take meds to avoid them in the future.
Ask Your Doctor
You have many options to deal with and to prevent a kidney stone. Be sure you understand the pros and cons of each treatment, including doing nothing.
Ask your doctor:
- How long should I wait for my stone to pass on its own?
- How much water should I drink?
- What foods should I eat?
- For which symptoms should I call you?
- What can I do to prevent another stone from forming after treatment?
You may have heard the old line about kidney stones: These, too, shall pass. Better yet, don’t get them in the first place. They’re easier to avoid than you might think.
With the right foods, plenty of water, and proper medication, you can lower your chances of kidney stones. Maybe you’ll pass them right out of your life.
Who Is More Likely to Get Them?
“Kidney stones” is a term that covers different types of small, solid crystals. They can have different causes and different food culprits. Some are related to kidney infections. Others form because you have too much of certain minerals in your system.
Genes can play a role, too. Forty percent of the people who get kidney stones have relatives who have them, too. Their bodies may get rid of too much calcium or too little citrate (a chemical found in citrus fruits) in their pee, for instance.
Other conditions that make kidney stones more likely include:
Obesity . When you’re overweight, you tend to get them more often. The same is true if you havediabetes.
Gout. This painful condition happens when uric acid builds up in your blood. That makes crystals form in the joints or kidneys.
Intestinal surgery. If you’ve had certain types of gastric bypass surgery or other intestinal surgery, your risk may go up.
Certain kidney diseases. One example is polycystic kidney disease, in which clusters of cysts grow in your kidneys. Another is medullary sponge kidney, a birth defect that causes cysts to form in the organ’s tubes.
Middle-aged men are most likely to get kidney stones, though it can happen to people of any age or gender.
Things to Watch Out For
Even if you’re in good health, your diet may encourage kidney stones to grow. One top reason is you may not be drinking enough water. That means you’ll make too little pee, which gives the stones more chances to form.
Other things to watch:
Colas: These beverages are high in fructose and phosphates, which may lead to kidney stones.
Oxalates: These are organic compounds found in a number of foods, including healthy ones such as spinach and sweet potatoes. But oxalates also bind easily to certain minerals, including calcium, which then help form kidney stones.
Salt (specifically, sodium): Lots of sodium, which you get mainly through salt, means more calcium in your pee. That ups you odds for kidney stones. Eating calcium-rich foods like kale and salmon isn’t a bad thing — just when you also eat too much salt. Too little calcium in your diet may lead to kidney stones in certain people.
Animal protein: Too many steaks, chicken, eggs, and seafood can build up calcium and uric acid in your body. That’s another cause of kidney stones.
Previous kidney stones: If you’ve had them once, you’re likely to get them again, unless you take steps.
What You Can Do
Take charge of your diet and take any meds your doctor prescribed. Also try to:
Drink lots of water: Stay hydrated, especially when you exercise.
Check food labels: Read the ingredients. Avoid or eat less of foods with high amounts of ingredients like sodium chloride, monosodium glutamate (MSG), and sodium nitrate.
Choose foods wisely: Usually it’s good to get more spinach and nuts in your diet. But if you have calcium oxalate stones, which are the most common type, your doctor may tell you to avoid limit foods high in oxalates:
Nuts, including almonds, cashews, pistachios, and peanuts
Soy products, including soy burger, soy milk, and soy cheese
Chocolate
Oat and oat bran
Red kidney beans, navy beans, fava beans
Beets, spinach, kale, tomato
These foods are low in oxalates. Caution: Too much dairy foods and animal protein can up your chances of less common types of kidney stones:
Grapes, melon, bananas
Cucumbers, cauliflower, cabbage, peas
Cheese, milk, butter
Beef, bacon, chicken, ham
Eat citrus fruits. Lemons and limes are high in citrate, which helps prevent kidney stones.
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