Pyelonephritis (also known as a kidney infection) occurs when a urinary tract infection has travelled to the upper urinary tract (which includes the ureters and the kidneys).
It is a more serious condition than ordinary urinary tract infections, which typically only affect the urethra and bladder.
The primary job of the kidneys is to filter waste from the bloodstream, producing urine that travels down the ureters and into the bladder. The bladder voids the urine out of the body through the urethra.
Women are more likely than men to get urinary tract infections and pyelonephritis. This is because a woman’s urethra is shorter than a man’s, so it is comparatively easier for bacteria to travel to the urinary tract organs.
Most kidney infections begin as lower urinary tract infections, which worsen as they progress up the urinary tract. The symptoms of a UTI include:
- Painful, stinging or burning sensation with urination (dysuria)
- Frequent urination
- Persistent urge to urinate, even after the bladder has just been emptied
The symptoms of a urinary tract infection, plus these additional symptoms, may indicate a case of pyelonephritis:
- Fever, chills, nausea, and/or vomiting
- Back pain or pain in the sides
- Disorientation or confusion (especially in seniors)
- Changes in the urine (bloody, cloudy, or smelly)
Pyelonephritis is usually caused by the same bacteria that cause a typical urinary tract infection: the bacteria found in the colon. These bacteria can live on the skin surrounding the anus, and can sometimes get into the urinary tract. Better hygienic habits can help prevent the spread of these bacteria.
Additionally, if the immune system is suppressed, the body is less likely to be able to fight off a kidney infection. Some conditions that suppress the immune system include:
- Immunosuppressant medication, such as those after an organ transplant
- Immune disorders
Kidney infections can also occur when the urine is unable to flow freely and flush out harmful bacteria. Some reasons why women’s urine flow could be reduced include:
- Kidney, bladder, or ureter stones
- Tumors in the abdomen or pelvis
- Birth defects that affect the shape of the urinary tract
If you’re experiencing symptoms of pyelonephritis, make an appointment with your doctor right away. Your doctor will conduct a physical exam, and may perform one or more tests to confirm your diagnosis.
You will be asked to provide a urine sample, which the lab technicians will examine under a microscope. If your urine contains too many white blood cells or bacteria, you may have a UTI or pyelonephritis.
Your doctor can grow a culture using the bacteria found in your urine. This can help identify the type of bacteria living in your urinary tract.
If an infection is found in the blood, this may be an indication of severe pyelonephritis.
An ultrasound can be used to detect stones or other masses in your pelvis.
Computed tomography (CT) scan
CTs scans use X-rays to create a 3-D image of your internal organs, which can be helpful in diagnosing pyelonephritis.
Treating for Pyelonephritis
Because pyelonephritis is a potentially serious medical condition, doctors recommend medical intervention right away. Fortunately, pyelonephritis can be treated very effectively with a seven-day regimen of antibiotics. Most patients can take the antibiotics orally at home.
However, patients who are vomiting will not be able to keep the oral medications down. In addition, people who are disabled or confined to a bed may have a hard time taking care of themselves without extra help. In these cases, it’s recommended that the patient is hospitalized and receives intravenous antibiotics.
Abscesses are small “pockets” of infected tissue that can sometimes form in serious cases of pyelonephritis. They must be drained through a tube inserted through the skin and into the kidney, with the help of a healthcare provider.
Chronic Kidney Infections
Although most cases of pyelonephritis occur on a singular basis and do not persist after successful treatment, some patients may suffer from chronic pyelonephritis.
Chronic pyelonephritis usually results from a congenital defect in the kidneys characterized by extensive scarring and degeneration. The condition is usually found in children. If you or your child is diagnosed with chronic pyelonephritis, your doctor will refer you to a specialist in renal care.