Jeffrey W. Hull, MD, FAAP, practicing pediatrician, provided the following definition of pus in his online resource "Parents' Common Sense Encyclopedia," posted on his website (accessed Dec. 19, 2007):

“Pus is formed by the collection of large numbers of white cells [leukocytes] called polymorphonuclear cells in a localized area of the body in response to the presence of bacterial infection.

These cells break down and release chemicals that kill the bacteria as well as cause enlargement of the blood vessels (inflammation) and attract more white cells to the ‘fight.’…

Polymorphonuclear cells are of three types: neutrophils, eosinophils, and basophils. Neutrophils fight bacterial infection. They form pus and are the chief ingredient of an abscess.”

Chart of the Different Types of White Blood Cells (Leukocytes)
Types of White Blood Cells:

Pus is primarily dead neutrophils cells


Dec. 19, 2007