Could My Lower Back Pain Be Related To My Kidneys?

Lower back pain is rarely caused by a kidney problem, but it’s common to mistake lower back pain for kidney pain. Kidney problems are easier to identify through other symptoms, like pain when you urinate. Rather than being kidney-related, your lower back pain is more likely caused by a musculoskeletal problem such as a strain¹ or slipped disk.

Mistaking kidney pain for back pain is common, but you should talk to your doctor if in doubt. They can determine what is causing your pain, reassure you, and help you get better.

Could your lower back pain be kidney-related?

Understanding what kidney pain usually feels like will help you figure out if your pain is caused by a kidney problem or a musculoskeletal problem.

Common features of kidney pain include:

1. You feel pain higher and deeper in your back. Your kidneys are on either side of your spine below your rib cage.

2. Kidney pain is usually felt on one side as most conditions that cause kidney pain only affect one kidney. Central pain or pain on both sides is more likely to be muscular.

3. Pain will increase when you apply pressure to the area. (This can also happen with muscular pain.)

4. Pain may spread into your groin on the same side.

5. You might feel a cramping sensation that comes and goes (unlike musculoskeletal pain which is usually constant).

The kind of pain you feel depends on the condition causing it.

What kidney-related conditions cause lower back pain?

Kidney pain is caused by many different conditions, including:

Kidney stones

Kidney stones² are very painful. They are caused when deposits of minerals and salt form inside your kidneys and crystallize and stick together. Kidney stones don’t generally cause damage, but they are painful when you pass them.

You can treat kidney stones by taking pain medication and drinking lots of water to encourage the stones to pass. You might need surgery to remove a stone if it has become lodged in your urinary tract. Shockwave lithotripsy is sometimes used to break up the stone, making it easier to pass.

Kidney stones can cause pain in your side and back just under the ribs. Other kidney stone symptoms include:

• Pain or a burning feeling when urinating

• Urine which is pink, red, or brown

• Urine which is cloudy or foul-smelling

• A persistent need to urinate, but you can only pass a small amount

• Nausea

Kidney stones are typically caused by³ dehydration, too much or too little exercise, consuming excess salt or sugar (especially fructose), a high-animal protein diet⁴, infection, obesity, medications, or genetics.

Kidney stones often reoccur at a rate of 10–30% within five years, so if you are diagnosed with a kidney stone, speak to your doctor about the cause. You may be able to stop kidney stones from returning by drinking more water or changing your diet⁵.

Urinary tract infection (UTI)

A urinary tract infection can affect the urethra or bladder and cause lower back pain. UTIs can go away on their own, but you might need to take painkillers or antibiotics to relieve your symptoms and get rid of the infection. Without treatment, the infection can travel to the kidney resulting in a kidney infection that usually causes more severe symptoms.

Common UTI symptoms include:

• Frequent urination

• A persistent urge to urinate, even if your bladder is empty

• Burning or pain when urinating

• Pus or blood in urine

• Cloudy urine

• Foul-smelling urine

• Pain in your lower tummy or back

• Fevers, nausea, and vomiting

The symptoms above don’t always mean you have an infection in your kidneys.

Kidney infection

A kidney infection will always cause UTI symptoms, but it may also cause more severe symptoms, including:

• Feeling weak or tired

• High temperature

• Shivering

• Loss of appetite

• Nausea

• Diarrhea⁶

• Pain in the back or groin

Kidney infections can be very serious, so speak to your doctor right away if you have any of the symptoms above. Left untreated, kidney infections can cause scarring which leads to chronic kidney disease and high blood pressure. Septicemia, a life-threatening condition, may occur when the infection enters your bloodstream.

Kidney infections are more common in women because they have a shorter urethra, so bacteria can travel from the bladder to the kidney more easily. They are also more common in people with weakened immune systems and those who have had a urinary catheter inserted. Kidney stones and cysts can be a risk factor for infection as well.

Kidney infections are usually treated with a short course of antibiotics, while more severe infections can lead to hospitalization.

Polycystic kidney disease (PKD)

According to the National Kidney Foundation, polycystic kidney disease is the fourth-leading cause of kidney failure, affecting 600,000 people in the US. PKD is a genetic disorder⁷ that causes fluid-filled cysts to grow in the kidneys. Besides kidney failure, it can cause high blood pressure.

There are two kinds of PKD:

1. Autosomal dominant polycystic kidney disease (ADPKD) — typically occurs in adulthood

2. Autosomal recessive polycystic kidney disease (ARPKD) — much rarer than ADPKD, often diagnosed at or before birth

Common PKD symptoms include:

• High blood pressure

• Pain in the back or side

• Abnormally large abdomen

• Blood in urine

• Frequent UTIs

Unfortunately, there is no cure for PKD and it should be closely monitored by a doctor. The cysts will continue to develop and eventually cause kidney failure, but how quickly this happens depends on different factors.

A healthy lifestyle can help to slow PKD’s progress by preventing causes of kidney failure, including high blood pressure. If you have been diagnosed with PKD, you should take steps to:

• Maintain a healthy weight

• Stay hydrated (try to drink at least three liters of fluid a day⁸ as this has been shown to reduce the risk of stones and cyst growth in ADPKD)

• Restrict your salt intake⁹ (about one teaspoon of salt per day) as salt drives cyst growth and high blood pressure in ADPKD

• Exercise for at least 150 minutes¹⁰ per week (try to avoid contact sports to reduce the risk of cysts bursting)

• Get enough high-quality sleep

• Quit smoking

If you have PKD symptoms, speak to your doctor. They can prescribe medications to control high blood pressure and ACE inhibitors or ARBs to delay kidney failure. Your doctor may also refer you to a nutritionist who can help you adapt your diet.

There is a risk you will pass PKD on to your children as it’s hereditary, but you can speak to your doctor about screening.

Injury

Although your kidneys are well protected, strong impact or a blunt force blow to the kidney area can cause physical damage¹¹ or disrupt normal blood flow. This can cause sudden kidney failure in extreme cases.

Common symptoms of injury-related kidney damage include:

• Kidney pain that comes after an accident, fall or engaging in contact sports

• Blood in the urine (may not be visible to the naked eye)

• Bruising

The kidneys are well protected and resilient against damage — they often recover from minor damage with little or no intervention. Physical kidney damage is usually treated with rest, but you may be asked to stay in the hospital for monitoring during your recovery.

More serious damage may require surgery, and if a kidney is too damaged, it may be removed. You can live a perfectly healthy life with only one kidney.

Kidney cancer

Lower back pain is rarely a symptom of kidney cancer¹² — it is more likely to be caused by kidney stones as the pain is usually felt in a similar place on one side. However, you should see a doctor if you have lower back pain and any of the following kidney cancer symptoms:

• An obvious lump over the kidney

• Blood in urine

• Fatigue

• Loss of appetite

• Unexplained weight loss

• Anemia

• Persistent fever

Cancer will likely be quite advanced if the pain becomes a symptom. Only people at high risk are screened for kidney cancer¹³, including if they have a family history of the disease.

The five-year survival rate for cancer localized to the kidney is 93%¹⁴, partly because many small kidney cancers are extremely slow growing and some kidney tumors are completely benign.

Cancer that has not spread beyond the kidney is typically treated with surgery or other local treatments such as cryoablation. Chemotherapy usually has poor outcomes for kidney cancer, so doctors and scientists are working to develop targeted drugs to treat advanced kidney cancer, with or without surgery.

Slipping rib syndrome

Slipping rib syndrome¹⁵ is not a kidney condition, but you might easily mistake it for one. It's caused when the lower ribs (sometimes called false ribs) move more than they are supposed to.

Slipping rib syndrome symptoms include:

• Pain on one side of your lower chest or upper abdomen (usually occurs at the front of your body rather than the back)

• Pain when pressure is applied to the area

• Popping or clicking (usually worse when you cough, twist, bend or laugh)

The condition is often caused by a blow to the chest from a fall or contact sports, or by overdoing it with quick twisting or lifting.

A medical professional can carry out a simple physical exam to diagnose slipping rib syndrome, and it usually goes away in a few weeks. Your doctor might recommend taking non-steroidal anti-inflammatory drugs (NSAIDs), applying heat or ice, wearing a chest binder, or avoiding heavy lifting for a while.

The condition can become chronic and require surgery in rare cases.

When to see a doctor about lower back pain

If you have pain in your lower back alongside any other symptoms, speak to your doctor. If your pain is kidney-related, the most likely cause is kidney stones. Your doctor can also rule out more serious causes, such as an infection or cancer. Most kidney conditions that cause pain are easy to treat and quick to resolve.

You should always see a doctor if you have pain in your lower back after an accident, fall, or blow, as this can (rarely) indicate serious kidney damage that needs surgery.

Be aware that back pain and kidney pain are often confused with each other. Don't be surprised if your doctor says your pain has actually been caused by damage to your back or ribs, not your kidneys. Back injuries can also be checked out by a doctor, so always seek professional advice if you’re unsure.

The lowdown

Kidney pain is less common than people think, but it’s easy to mistake kidney pain for back or rib pain caused by a sprain, slipped disk, or slipping rib syndrome.

If the pain in your lower back is kidney pain, it is probably caused by kidney stones which are easy to treat — although your doctor might recommend diet changes to reduce the risk of them coming back.

Lower back pain is rarely a symptom of a serious kidney problem, but ask your doctor for a check-up for any kind of back or side pain. Take note of your other symptoms, such as a high temperature or loss of appetite, as these might suggest you have a kidney infection. If left untreated, kidney infections can cause serious permanent damage.

Note that lower back pain isn’t a sign that your kidneys are failing — kidney failure is painless. If your pain is kidney-related, the cause will most likely be treatable.