
If you’ve heard one thing about kidney stone symptoms, it’s probably the excruciating pain part.
The rumors are, unfortunately, true: Of all the signs of kidney stones, the particular kind of agony they can cause is typically the clearest one. So it’s a good idea to familiarize yourself with how exactly that exquisite pain presents, as well as the handful of other symptoms you can experience with a kidney stone. Here’s hoping the following information never comes in handy.
What are kidney stones?
“Kidney stones are small, hard deposits of mineral and acid salts that form on the inner surface of the kidneys,” Roger Sur, M.D., director of the Comprehensive Kidney Stone Center at UC San Diego Health, tells SELF.
True to their name, kidney stones look like little pebbles that can vary in color (usually yellow or brown), texture (smooth or jagged), and size (from a grain of sand to a pea (major ow), according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). In rare nightmare scenarios, they can even reach the size of a golf ball (no words).
Kidney stones are made of minerals normally found in your pee, like calcium, oxalate, and phosphorus, that don’t cause issues at low levels, the NIDDK explains. As these minerals start to accumulate and crystalize, they can begin to stick together—often when the urine becomes more concentrated, the Mayo Clinic explains.
There are four main types of kidney stones, categorized by the stuff they’re made out of and why they form.
What causes kidney stones?
The likely cause of your kidney stone depends on the type you have. In some cases, there is a specific and direct cause, like having a certain medical condition or a urinary tract blockage. But many times, it’s hard to say why certain individuals get kidney stones.
“A lot of times, we don’t know the exact cause,” James Simon, M.D., a nephrologist at Cleveland Clinic, tells SELF. The thought is that it’s commonly a mix of a genetic predisposition or medical issues and dietary factors, Dr. Simon says. For instance, having a family or personal history of kidney stones and not drinking enough water may both be risk factors for getting kidney stones, according to the NIDDK. It could also be a combination of several possible risk factors, like obesity, digestive issues, or taking diuretics.
That said, here are the four types of kidney stones and some of their proximate causes.
1. Calcium stones
These are by far the most common kind, accounting for up to 75 percent of kidney stones, according to the U.S. National Library of Medicine. Normally, extra calcium that doesn’t get used up by your bones and muscles goes to the kidneys to be flushed out with the urine. When the calcium starts to build up and bind with other waste products in the kidney, it can form a small stone, the NIDDK explains.
Sometimes this just happens for reasons we don’t know, and sometimes it happens because of a medical condition that causes excess calcium in the urine (like hypercalciuria and hyperoxaluria) or blood (like hyperparathyroidism), per the NIDDK.
2. Uric acid stones
These can form when your pee contains excess acid. This is sometimes due to eating particular proteins like fish, shellfish, and meat (especially organ meat), per the NIDDK, or being dehydrated, according to the Mayo Clinic. Gout can also increase your risk of uric acid stones, along with certain genetic factors, the Mayo Clinic says.
3. Struvite stones
These tend to develop after someone has a UTI, and can come on quickly, according to the NIDDK.
4. Cystine stones
Cystine stones are due to a genetic disorder called cystinuria that causes the amino acid cystine to leak out of the kidneys and into the urine, the NIDDK explains.
Kidney stone symptoms to be aware of:
Fantastic news, y’all: It’s actually totally possible to have a kidney stone and never even know it. In fact, that’s often the case with tiny kidney stones, which can pass undetected out of the body, Dr. Sur says. “A lot of them out there are never found, or we find them incidentally when we’re looking for other things,” Dr. Simon adds.
Of course, some kidney stones can cause pretty miserable symptoms. If you experience any of these signs of kidney stones, you’ll want to see a doctor ASAP to help you figure out what you’re dealing with and how to help you.
1. Sharp pain in the kidney area
Now, about that infamous pain. It usually begins when the stone dislodges from the kidney and enters the ureter, the little tube between the kidneys and the bladder. If the stone is big enough to plug the ureter up, it can cause the urine to flow back into the kidney, causing swelling and an immense amount of pain at the site of the affected kidney, Dr. Simon says.
“The pain is going to be sharp, severe, and often suddenly onset,” Dr. Simon says. It’s classically felt in the flank area—at the bottom of the rib cage in your side and back. Generally speaking, “The bigger the stone, the harder it is to pass, the more painful it is,” Dr. Simon says. “But even small stones can hurt.”
If the pain is so bad that you can’t sit still or get comfortable, that’s a sign to seek emergency care, Dr. Simon says.
2. Pain that comes and goes
It’s also not unusual for the pain to come in waves or fluctuate in intensity, according to the Mayo Clinic. “It can come and go, getting a little worse and a little better as the muscles in the ureter try to push the stone forward,” Dr. Simon explains.
3. Pain in the stomach or groin
The pain around the kidney may radiate down into the abdominal or groin area, Dr. Simon says. The pain can shift locations as it moves down the urinary tract, per the Mayo Clinic.
4. Nausea and vomiting
“Some people are in such severe pain that they start throwing up,” Dr. Simon says.
5. Fever and chills
This indicates you may also have an infection going on, per the Mayo Clinic.
6. Red, pink, or brown urine
This is a sign of blood in the urine, thanks to a passing stone nicking tiny blood vessels in the tissue along your urinary tract, Dr. Simon explains. (But often the amount of blood is so tiny that it would only be picked up by a urinalysis, Dr. Simon adds.)
7. Urinating frequently or a small amount at a time
These urinary sensations often begin when the stone is blocking the flow of urine or sitting in the bladder and irritating it, Dr. Simon says.
What to expect from kidney stone treatment:
Doctors typically use an exam, imaging tests (like an X-ray or CT scan), and medical history to help diagnose a kidney stone, according to the NIDDK. The diagnosis will help determine the treatment plan, which really depends on the type of stone, the cause, the location, and the symptoms you’re suffering from, Dr. Simon says.
Small stones can often be passed simply with time, water, and over-the-counter pain meds, according to the Mayo Clinic. Your doctor might also prescribe an alpha blocker, which helps relax the ureter to help you pass the stone more easily.
Larger stones that are causing debilitating pain and/or blocking your urinary tract might need more intensive treatment, according to the NIDDK. That can include pain medicine and I.V. fluids to manage pain and dehydration (from vomiting), as well as a procedure to break up or remove the stone. For instance, doctors can use sound waves to break up the stones or a surgical procedure to remove it, the Mayo Clinic explains.
How to prevent kidney stones
What you can do to prevent future kidney stones depends on the type of stone and your medical history, so you’ll want to speak with your doctor about your options, Dr. Simon says. Prevention strategies might involve drinking plenty of water, making dietary adjustments (like reducing salt or animal protein intake), or taking various medications to help moderate the levels of certain minerals in your urine, the Mayo Clinic explains.
Additional reporting by Claire Gillespie.
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