Kidney Infection / Pyelonephritis

Your kidneys have a range of important functions in your body. These functions include filtering as well as excreting waste products from your blood as it circulates through the capillaries within your kidneys. It also regulates blood pressure, maintains steady levels of electrolytes (calcium, phosphorus, sodium, potassium, and chloride) and contributes to red blood cell production.

Where are the kidneys located?

They are located on either side of your body just beneath your diaphragm near the lower back. The kidneys work to filter blood to produce urine. Two tubes called the ureters transport urine from the kidneys down to the bladder. Each of your kidney is connected to the bladder in the pelvis by ureters that drain urine from the kidneys to the bladder. The urine in the bladder is disposed from the body through the urethra. These structures make up the urinary tract.

Pyelonephritis is a painful and unpleasant kidney infection.

What causes Pyelonephritis?

It is caused by bacteria travelling from your bladder into one or both of your kidneys.

Most urinary tract infections (UTIs) involve the bladder and urethra. Pyelonephritis  is a result of an UTI progressing upwards to involve the kidneys and ureters.

What causes Pyelonephritis?

Most cases of pyelonephritis are complications of common bladder infections. Bacteria enter the body from the skin around the urethra. They then travel up the urethra to the bladder.

Bacteria sometimes escape the bladder and urethra traveling up the ureters and affect one or both kidneys.

Pyelonephritis is potentially a serious kidney infection that may spread to the blood and causing severe illness. Thankfully, Pyelonephritis is almost always curable with antibiotics.


Symptoms of a kidney infection normally develop quite quickly over a few hours or days. Common symptoms Pyelonephritis include:

  • Pain and discomfort experienced on your side, lower back or around your genitals
  • High temperature (may reach 39.5C or 103.1F)
  • Shivering or chills
  • Feeling very weak or tired
  • Loss of appetite
  • Feeling sick or being sick
  • Diarrhea

Other symptoms may also be experienced if you also have cystitis or urethritis (infection of the urethra). These additional symptoms may consist of:

  • Pain or a burning sensation during urination
  • Feeling the need to urinating frequently or urgently
  • Feeling that you’re unable to urinate fully
  • Blood in urine
  • Cloudy or foul smelling urine
  • Pain in the lower abdomen



Treatment with antibiotics is always required to treat pyelonephritis. Home remedies on its own isn’t effective or recommended for the condition.

Generally, antibiotics are prescribed for a total of at least 7 days. Part of the treatment may be administered in the hospital intravenously. The remainder of the treatment may be taken as pills at home.

Pyelonephritis rarely progresses to form a pocket of infection (abscess). When an abscess forms, it is difficult or impossible to cure with antibiotics alone and must be drained. This procedure is known as nephrostomy.

This is often performed with a tube inserted through the skin on the back into the kidney abscess.

Acute and Chronic Pyelonephritis

  • Acute pyelonephritis: In most cases are acute. This means that is sudden and self-limited. After treating with antibiotics, there are rarely any lasting damage to the kidneys. In most cases, people do not develop the illness again.
  • Chronic (long-lasting) pyelonephritis: This condition is rare. It is usually caused by birth defects in the kidney. Repeated UTIs, usually in children can result in progressive damage and scarring in the kidney which may eventually cause kidney failure. Chronic pyelonephritis is  normally discovered in childhood.



  • History: You are required to tell your doctor a history of your illness and list specific symptoms to help your doctor make the diagnosis of pyelonephritis.
  • Physical examination: A doctor will evaluate a person’s general appearance, detect vital signs and press over the kidneys to check for tenderness.
  • Urinalysis: Microscopic analysis of the urine always show signs of infection. This may include an excess of white blood cells and bacteria.
  • Urine culture: Bacteria in urine may grow on a culture dish within days. This allows the best antibiotic to be chosen.
  • Blood cultures: In cases where pyelonephritis has spread to the blood, blood cultures can identify this and guide treatment.
  • Computed tomography (CT scan): A rapid series of X-ray images are taken and a computer creates detailed images of the abdomen and kidneys. This scan is not necessary to diagnose pyelonephritis but it sometimes help.
  • Kidney ultrasound: High-frequency sound waves are directed through the skin to create images of the kidneys and ureters. An ultrasound can help to identify abscesses, stones, and blockages.

On top of diagnosing pyelonephritis, doctors will look for any conditions that make the occurrence of pyelonephritis more likely. For instance, kidney stones or birth defects of the urinary tract can increase the chances of an infection. Both are potentially correctable. This will reduce the chances of future kidney infections.