Kidney stones and infections are among the leading causes of kidney pain. However, injury to the kidneys as well as other types of illnesses may also be the culprits. Kidney pain causes can include kidney infections—these are a type of urinary tract infection (UTI) that travels to one or both kidneys.

A heart-healthy diet and lifestyle will protect your kidneys. However, kidney function can decline with age in some people, although it doesn’t necessarily cause a problem unless other health conditions are present. Smoking, excessive alcohol consumption, high blood pressure, and high blood sugar (diabetes) all harm the kidneys and can lead to chronic kidney disease.

A urinary tract infection usually causes symptoms such as unusually frequent urination, an intense urge to urinate, pain, discomfort, or a burning sensation during urination, and awakening from sleep to pass urine. Pain, pressure, or tenderness in the area of the bladder can also occur.

For instance, a kidney stone that gets lodged in the ureter causes waves of intense pain, rather than the steady ache of typical low back pain. And a person with a kidney infection (pyelonephritis) almost always has a fever along with flank pain.

UTIs can occur anywhere in the urinary tract, with common sites being the bladder and the urethra. Less common, but more serious, is infection of the kidneys. Infections may be triggered by sexual activity, catheters, and other factors.

The infections are usually caused by Escherichia coli, a bacterium that lives in the intestinal system. If E. coli are carried from the rectum to the vagina, they can enter the urethra and infect the bladder. Risk factors for UTI vary with age.

UTIs become more severe kidney infections when the bacteria ascend from the bladder to the kidney. Such infections can cause high fevers, permanent kidney damage, or even sepsis. The rise in cases of antibiotic-resistant bacteria is also concerning.

For more information on kidney pain and potential treatments, visit University of Utah Health.