Pus

One characteristic of the activated neutrophil is it's adherent capacity. This characteristic is essential for the migration of the cell. Because of this, neutrophils can easily aggregate. In some cases, it is important not to confuse cell aggregation and pus. Pus is formed of degenerated neutrophils (pyocytes) and cellular debris compacted into a mass where cell identity is lost. This discrimination is not commonly used with the urinary sediment, so that many aggregates are reported as pus. The term pus should be restrained to real pus.