The Most Common Causes and Treatments of Kidney Infection

Kidney infection is a serious condition that usually takes place when bacteria travels up the tube between the bladder and the kidneys.  

The medical name for this condition is pyelonephritis. Unlike cystitis which is a common infection of the bladder that makes urinating painful, it is more severe and unpleasant, therefore, requires immediate medical attention.

If not treated properly, it may lead to life-threatening complications, causing permanent damage to your kidneys.


Often, the symptoms of a kidney infection develop quickly over a few hours or days. Some of the most common symptoms include:

  • High temperature
  • Shivering
  • Chills
  • Loss of appetite
  • Feeling sick
  • Pain in your lower back and around your genitals
  • Feeling very weak and tired
  • Diarrhoea

Those who have cystitis or urethritis may also experience other symptoms including:

  • Burning sensation during urination
  • A frequent urge for urination
  • Blood in your urine
  • Cloud and foul-smelling urine
  • Pain in your lower abdomen

Symptoms in Children:

Children with kidney infection may usually develop the following signs and symptoms:

  • A lack of energy
  • Irritability
  • Inadequate feeding
  • Abdominal pain
  • Jaundice
  • Blood in the urine
  • Foul-smelling urine
  • Bedwetting

Causes of Kidney Infection:

Most kidney infections occur due to a bladder infection. Bacteria that travel up the tube between the bladder and kidney can multiply and enter your kidneys. These bacteria usually live in the bowel – e.g., E.coli. Often, people with cystitis don’t get a kidney infection.

Some kidney infections can develop from the problems in the kidney. For example, people may develop kidney infections if they have a kidney stone or an abnormality in the kidneys.

It is usually only one kidney that gets affected. A kidney infection can develop at any age. Both women and children are more at risk of developing a bladder infection. In women, the urethra is closer to the anus, which makes it easier for bacteria to reach the urethra. The urethra is also shorter in women than in men so that bacteria can travel up to the bladder more easily. However, they are uncommon in men.

In rare cases, a kidney infection can develop if bacteria or fungi infect the skin and the infection spreads through your bloodstream to your kidneys. However, this type of infection can also develop in people with weakened immune systems.

Other Factors Responsible for Kidney Infection:

  • Having a condition that blocks or obstructs your urinary tract, such as kidney stones or an enlarged prostate.
  • Having a weak immune system – for example, due to type 2 diabetes.
  • Having an infection of the prostate gland called prostatitis.
  • Having a urinary catheter.
  • Being female and sexually active – sexual intercourse allows bacteria to travel through the urethra and reach the bladder.
  • Being a man who has anal sex- bacteria can enter through the urethra and travel into the bladder.
  • Being pregnant – this condition triggers physical changes that affect the flow of urine out of the body while allowing bacteria to spread to the kidneys.


Antibiotics for Kidney Infections:

Most cases of kidney infections can be treated with the course of antibiotics. You will usually be recommended a course of antibiotic tablets or capsules that lasts between seven and 14 days.

For most people – apart from pregnant women – antibiotics called ciprofloxacin or Co-amoxiclav are most commonly prescribed. Some patients complain of feeling sick and diarrhoea after taking ciprofloxacin.

A 14-day course of an antibiotic called cefalexin is also prescribed for pregnant women.


Taking a sedative such as paracetamol should help relieve symptoms of pain and high fever.

In both cases, it is essential to seek medical attention. Depending on the severity of the condition, the course will be determined.

Hospital Treatment for Severe Kidney Infections:

In some instances, you may require hospital treatment, and it is needed when:

  • You are extremely dehydrated
  • You are unable to swallow or keep down any fluids and losing consciousness
  • You are pregnant, and you have a high fever
  • You have a weakened immune system
  • You have diabetes
  • Your general health condition is poor
  • Your symptoms show no sign of improvement 24 hours after treatment starts
  • You have additional problems such as rapid heartbeat and losing consciousness

Surgical Treatment for repeated kidney infections:

If you have recurrent kidney infections, you may need to see a kidney specialist or urinary surgeon for an evaluation. Surgery might be recommended to repair a structural abnormality.