Pus
Composed of two phases
- Solid:
- live/dead polymorphs, macrophages
- Bacteria/causative agent (eg irritant chemicals)
- Dead human cells
- Fluid: contains exudate
- Immunoglobulins (for opsonisation - 1IgG, 2IgM)
- Complement - chemotaxis, anaphylaxis, opsonisation
- Clotting factors
- Inflammatory mediators
Abscess
- Localised collection of pus
- If loculated = pus, if free = empyema
- Wall composed of granulation tissue "pyogenic membrane"
- Natural history is to dischage through line of least resistance
- enzymes released from polymorphs/macrophagtes break down long chain molecules
- increases osmotic pressure (as more molecules)
- Swells pus collection
- Discharges