Kidney stones are relatively common, affecting 1 in 10 Americans over the course of their lifetime. This number has increased significantly over the past 5 decades, likely due to sodium-rich diets being on the rise. 

While kidney stones are largely treatable, the pain of a kidney stone is frequently compared to the pain of given birth – it can be quite severe. In this article, we’ll talk about what kidney stones feel like, how to know if you have kidney stones, and when to head to the doctor. 

Kidney stones

If someone you know has had a kidney stone, you’ve likely heard about how painful a kidney stone is to pass. While kidneys lack the types of nerves that transmit pain signals to your brain, they are surrounded by tissue that does have those nerves. If a stone blocks the urinary tract, backed-up urine can cause the kidney to swell, pushing on the surrounding tissue and causing intense pain. 

However, kidney stones don’t just cause pain in the kidneys. As they move out of the kidneys, through the ureters (passageways that connect each kidney to the bladder), into the bladder, and out the urethra, they can push against each organ, causing pain and discomfort as they go. 

Types of kidney stones

There are several causes of stones in the kidneys. Some stones form due to poor diet, some because of infection, and others due to genetic factors. There are four primary types of kidney stones: 

• Calcium stones — About 80% of kidney stones are calcium stones, made primarily of calcium oxalate. Nuts and chocolate contain high levels of oxalate, but it is also produced naturally in the liver. Calcium kidney stones can also take the form of calcium phosphate, which is often associated with metabolic conditions or certain prescription medications. 
• Struvite stones — These stones form in alkaline urine, and make up about 10% of all kidney stones. Urine can become more alkaline during urinary tract infections, when large quantities of bacteria release ammonia as a waste product. Though uncommon, these stones can grow very quickly.
• Uric acid stones — Accounting for only 5-10% of all kidney stones, these stones often form due to malabsorption disorders, or a poor diet. People who eat diets high in protein and low in fruits and vegetables are more likely to develop uric acid kidney stones. 
• Cystine stones — Occurring in only 1% of kidney stone patients, cystine stones are caused by a hereditary condition called cystinuria. People who have this rare metabolic disorder often begin developing kidney stones in childhood. 

What are the symptoms of kidney stones?

The first signs of a kidney stone are felt when the stone begins to move around inside your kidney, or when it tries to pass into one of your ureters. Symptoms of a kidney stone include: 

• Pain or burning during urination
• Severe pain in the lower back and side
• Waves and fluctuations of pain, usually every 10-30 minutes. 
• Pain that moves into your lower abdomen and groin
• Intense need to urinate
• Red (bloody) or cloudy and foul-smelling urine
• Nausea, fever, and chills 

Kidney stone symptoms in women are generally the same as kidney stone symptoms in men. However, men may also feel extreme pain moving down to the tip of their penis as the stone enters the urethra. 

What causes kidney stones?

There is no single cause of kidney stones, though there are several factors that may contribute to their formation. Healthy urine contains uric acid, calcium, and oxalate, but they are diluted to manageable levels by the amount of fluid in your urine. Kidney stones are crystals that are formed when these substances no longer get diluted, and start sticking together to form solid masses. 

Dehydration is a major factor when considering kidney stone risk. Low volumes of urine contribute heavily to whether or not kidney stones develop into structures large enough to block your bladder or be felt as they move along your urinary tract. Adults who have had kidney stones before may be advised by their physician to drink at least 3 liters of water a day, to minimize the risk of new stones forming. 

Foods that can cause kidney stones

Diet is also a factor, especially for calcium kidney stones. Calcium stones form when there is a high concentration of calcium in the urine. However, this typically isn’t due to ingesting too much calcium, but rather, is due to a problem with how your body processes calcium. If you develop calcium stones, your provider will likely not recommend that you limit your calcium intake, as that could lead to other issues. Instead, they will probably ask you to cut back on sodium, as too much sodium in the urine prevents calcium from being diluted and reabsorbed. 

Salt-heavy dishes should be avoided if you are prone to forming kidney stones. All meats – beef, pork, chicken, and even fish – contain significant amounts of acid, which makes it easier for uric acid stones to form. Obesity, no matter what specific foods you are eating, can contribute to troubles with kidney stones, as well as myriad other health problems. 

Treatment for kidney stones

The type of recommended treatment for stones in your kidney depends on the type of stone you have, how long you’ve been experiencing problems with kidney stones, and the severity of the pain. Most often, the first course of action is to wait for the stone to pass on its own. This, of course, is only possible for smaller stones. If the stone is not small enough to pass on its own, or if the pain becomes unbearable, your provider may recommend taking medication to speed the process along. 

If medication does not work, there are a few surgical options available, especially if the stone is impairing kidney function: 

• Ureteroscopy (URS)
  This procedure is used for stones in the ureter and kidney. A URS is a tiny telescope that goes up the urethra that allows the doctor to see the stone without having to make an incision. Once the stones are found, a small device collects and removes them. The urologist will administer general anesthesia for the patient to minimize discomfort. 

• Shock wave lithotripsy (SWL)
  X-rays are used to find the stones, then shock waves are administered to break the stones up into smaller pieces that can pass through the urethra. Stones usually pass within a couple weeks. 

• Percutaneous nephrolithotomy (PCNL)
  For very large stones, your doctor may recommend PCNL. This procedure involves making a small incision, through which a nephroscope can pass and break large stones into smaller pieces. This is generally an inpatient procedure, and you may be asked to stay overnight at the hospital so the surgeon can monitor your vital signs. 

How to check for kidney stones

Once you experience symptoms in your kidney that indicate you may have a kidney stone, your doctor will likely order lab tests or diagnostic imaging to confirm. A urinalysis may be used to check for infection, or certain tests could be ordered to measure the amounts of minerals in your blood. 

Next, your provider might order an abdominal X-ray or CT scan to get a closer look at the stones. The size and location of the stones determines the path of treatment, so it’s important to get an understanding of where and how large they are. 

When do I need to see a doctor? 

It is possible for kidney stones to pass on their own. However, they can also cause major complications and severe pain if not treated. Seek medical attention as soon as possible if you experience the following symptoms: 

• Bloody urine 
• Difficulty passing urine
• Severe pain that does not get better when you shift position
• Fever and chills

Passing a kidney stone 

Even small kidney stones can cause severe pain. Where kidney stone pain is located will depend on how far along your urinary tract the stone has moved. Small stones generally take a couple weeks to pass from the kidneys into the bladder. However, how long it takes for a kidney stone to pass depends on the size of the stone. If a stone has not passed within 4 weeks, it is advised to seek medical attention. 

How to prevent kidney stones

A diet low in sodium and meat, and high in leafy greens and fiber can help prevent kidney stones. Regular exercise and a healthy body weight can also contribute to keeping stones at bay. There are so many factors, including inherited traits, that go into the formation of kidney stones that it is impossible to guarantee you will be able to avoid them through a healthy lifestyle alone. 

If you need to consult a physician regarding kidney pain, or how to check kidney function, schedule a consultation with a Tripment Health provider who can talk to you about your pain, and help you order the appropriate lab tests or diagnostic imaging.