Conditions and diseases

Kidney infection

Symptoms and causes

Symptoms and causes

What is a kidney infection?

A kidney infection or pyelonephritis is an infection of the upper urinary tract (ureter and kidney). Kidney inflammation usually starts as a bladder infection that spreads 'upwards'.

Unlike a bladder infection, a kidney infection is a serious medical problem that requires immediate medical attention. After all, if not treated adequately, a kidney infection can cause permanent damage to the kidney or can spread to the bloodstream, thus becoming life-threatening.

Diagnosis and treatment

Diagnosis and treatment

How is the diagnosis determined?

The kidney function is examined through a urine test, an ultrasound scan and a CT scan of the abdomen.


Kidney infections are treated with antibiotics. The choice of type of antibiotics and the duration of the antibiotic treatment depends on the general condition of the patient and on the type of bacteria found in the urine or blood tests. Recovery typically takes place after a few days of antibiotic treatment.

If the kidney infection is serious, hospitalisation may be appropriate, since IV antibiotic treatment is necessary for serious forms of kidney inflammation.

In the case of repeated kidney inflammation, check for structural abnormalities of the kidney, ureter or bladder that may give rise to kidney inflammation. These structural abnormalities are detected through X-rays. These tests should preferably take place after the inflammation has subsided, that is, preferably not during the acute phase.

Latest publication date: 15/05/2024