Wound Infection Vs Colonization

A wound can contain microorganisms without being infected. Colonization means that organisms are present and multiplying to a limited degree without invading tissue, producing a meaningful host response, or causing a clinically evident delay in healing. Many open wounds are colonized; a positive swab therefore describes what grew from the specimen, not necessarily what is harming the patient. Infection occurs when microbial invasion or proliferation triggers a host response and may injure tissue. The most useful question is not, “What organism grew?” but, “Is the wound behaving as infected tissue?” Increasing pain, erythema, warmth, swelling, purulent drainage, or malodor may indicate overt local infection. Infection can also be covert: healing stalls, granulation tissue becomes friable or hypergranulated, exudate increases, the wound breaks down, or new pain develops. The distinction affects treatment. Colonization generally calls for appropriate wound care and observation rather than antibiotics. Clinically infected tissue requires evaluation for source control, treatment of contributing problems, and antimicrobial therapy when indicated.