All chronic wounds will be contaminated with microorganisms. In colonised wounds there is bacterial reproduction, but this does not necessarily create a host reaction or infection in the wound bed. Therefore there is no rationale to start treatment with antibiotics unless indicated by other clinical factors.
If the wound becomes critically colonised or infected, treatment should be started. In an infected wound, the bacteria in the wound multiply and cause a host reaction with symptoms such as pyrexia, pain, swelling and exudates.
Additionally, there will be an elevated c-reactive protein (CRP), malaise, redness to the wound edges, localised erythema and pain. There may also be a strong odour to the wound and restricted function in the affected part of the body.