All information on leukocytes

At a glance

Leukocytes (white blood cells) are an important component of the body’s immune system as immune cells.

For more information

The so-called granulocytes are usually the largest subgroup of white blood cells in terms of numbers. They are especially important for the prevention of infections caused by bacteria, viruses, fungi or parasites.

They can recognize and destroy non-body structures. In case of infection or inflammation, the body produces more white blood cells and transports them with the blood to the place where they are required.

If one finds a high number of leukocytes (white blood cells) in the urine sample, one also speaks of a leukocyturia. This is usually caused by a bacterial infection of the kidneys and / or urinary tract.

But other inflammatory processes can also increase the number of leukocyts in the urine.

Leukocytes are constantly required and survive only for a limited time. Dead or damaged leukocytes are excreted from the body through the kidneys and finally through the urine. This happens on an ongoing basis. A small amount of white blood cells (up to 10 leukocytes per microliter) in the urine is therefore normal.


Among the most common causes of increased values are bacterial infections

  • of the urinary tract (bladder, ureter, urethra) or kidneys, as well as
  • in men of the prostate or epididyly testicles (rather less often).

In the case of a positive finding, the urine is often also examined in the laboratory and the number of leukocytes is determined.


  • Nagel, G. & Gehring, F. (2019): Leukozyten im Urin: Was erhöhte Werte bedeuten, URL: https://www.onmeda.de/laborwerte/leukozyten-im-urin.html, Retrieved 18.06.2019
  • Roche Diagnostics Deutschland GmbH (2014): Compendium of Urinalysis. Urine Test Strips and Microscopy, 1-196
  • Lahnsteiner, E. et al. (2004): Harnanalyse – praktisch zusammengefasst, 2. Auflage
  • Reiter, A. & Feichter, M. (2017): Leukozyten im Urin, URL: https://www.netdoktor.de/laborwerte/leukozyten/im-urin/, Retrieved 18.06.2019
Status of information: Autumn 2019