Kidney Pain: 8 Causes, How to Treat & What it Feels Like

Kidney pain can be caused by kidney stones, infections like pyelonephritis, hydronephrosis, kidney cysts, tumors, and injuries or blows to the kidney region.

Depending on the underlying cause, kidney pain may be accompanied by symptoms like fever, chills, abnormal urine color, blood in the urine, pain and burning when urinating, or strong-smelling urine.

Regardless of the cause of kidney pain, you should always consult a nephrologist or family doctor to identify the cause and initiate the most appropriate treatment. If the pain is very intense, you should proceed to the nearest emergency room.

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What causes kidney pain?

The main causes of kidney pain include:

1. Kidney stones

The presence of kidney stones can cause intense pain that can radiate to the stomach or genitals, pain with urination, and urine that is pink, red or brown, due to the presence of blood. 

Also recommended: Top 10 Kidney Stone Symptoms (with Online Symptom Checker)

How to treat: Treatment depends on the type of kidney stone present. It can include the use analgesics, diet changes, or laser treatment to reduce the stone to smaller pieces, allowing it to be easier eliminated through the urine.

Check-out some home remedies for kidney stones that you can use to complement your prescribed medical treatment.

2. Infection

Symptoms of a kidney infection include strong pain in the lower back, frequent urination, or urine with a strong odor. In some cases, you may also experience fever, chills, nausea and vomiting. 

How to treat: You should increase your fluid intake greatly to help eliminate the microorganisms causing the pain. Bacterial infections can be treated with antibiotics, as prescribed by a doctor. 

3. Single cyst or polycystic kidney 

Symptoms of a kidney cyst appear when the cyst is already large. It can cause pain, urine with blood, high blood pressure and frequent UTIs.

How to treat: Treatment should be guided by your doctor, and can be completed with medication when the cyst is small. Surgery may be indicated for the removal of larger cysts. 

4. Hydronephrosis 

Hydronephrosis is a swelling of the kidney due to the accumulation of urine that is not able to flower into the bladder. It causes pain in the lower back, blood with urine, fever and chills. 

How to treat: You should see your doctor to remove the accumulated urine from the kidney and identify the underlying cause, which may be kidney stones, a severe UTI or a kidney tumor. 

5. Renal vein thrombosis or ischemia

Renal vein thrombosis is an obstruction of the vein that carries blood to the kidney, caused by a blot. It leads to reduced blood flow and ischemia, which can cause cell death and the onset of acute renal failure.

This is a very rare and difficult situation to detect, as is usually not associated with symptoms. The symptoms it may cause are often confused with other conditions. In addition to pain in the kidneys, there may be blood in the urine and decreased urine output.

How to treat: it is important to see a doctor so that imaging tests can be carried out to identify the underlying cause of kidney pain. This condition is treated with the use of anticoagulant medication and/or surgery, depending on the severity of the problem.

6. Injury and trauma

Injuries or blows to the back, especially at waist-height, can cause inflammation and pain in the kidneys. 

How to treat: You can apply a hot water compress on your back and rest. Analgesics may also be taken to help with pain. If pain persists, however, you should seek medical attention. 

7. Back problems

Some back problems, such as poor posture, repetitive strain, a herniated disc or an inflamed sciatic nerve, can cause pain at the bottom of the back, which is where the kidneys are located.

How to treat: In these cases, it is important to consult a general practitioner for assessment. The doctor may order diagnostic tests, such as an X-ray of the spine, if necessary, in order to identify the underlying cause and indicate the most appropriate treatment.

8. Cancer

Pain caused by kidney cancer normally appears in its advanced stages. It is characterized by pain on sides of abdomen and in the back, as well as blood in the urine. 

How to treat: Treatment is completed with a medical oncologist and will depend on the tumor stage. It may include surgery, cryotherapy, the use of ultrasound and the use of medication to relieve symptoms. Renal tumors normally do not respond well to chemotherapy or radiation. 

Signs and symptoms of a renal problem 

Report your symptoms below to assess your risk for a kidney issue: 

  1. 1. Frequent urge to urinate
  2. 2. Urinating small volumes at a time
  3. 3. Constant pain in the lower back
  4. 4. Swelling of the legs, feet, arms, or face
  5. 5. Itching all over the body
  6. 6. Excessive tiredness for no apparent reason
  7. 7. Changes to urine color or smell
  8. 8. Presence of foam in the urine
  9. 9. Difficulty sleeping or poor sleep
  10. 10. Loss of appetite and metallic taste in the mouth
  11. 11. Feeling of pressure in the belly when urinating

Kidney pain during pregnancy 

Kidney pain during pregnancy is generally caused by spinal changes from weight changes in the abdomen. Rarely is pain related to renal issues, but if there is one present, symptoms like pain with urination will occur. You should see your OB if you have any additional symptoms to identify the underlying problem and prevent complications. 

To relieve pain, you can place a hot water compress in the affected region and rest in a comfortable position with your feet elevated. This position can relieve back pain and reduce swelling in the feet. 

What kidney pain feels like

Kidney pain is felt in the lower back or side of the body (either one side or both).

Generally, this type of pain is sharp, intense, and cramp-like, and can radiate to the groin or abdomen. It can also cause constant pain in the upper abdomen and back, and does not improve even with position changes.

Kidney pain may also be associated with other symptoms, such as pain or burning when urinating, the need to urinate frequently, decreased or absent urine, blood in the urine, cloudy or foul-smelling urine, fever above 38º C (or 100.4ºF), nausea or vomiting.

It is important to seek urgent medical attention if you feel kidney pain so that the cause can be diagnosed and treated. Prompt treatment can help to prevent complications, like a serious kidney infection, kidney abscess or kidney failure.