Microbiota is a primary cause of pathogenesis of chronic wounds.

OBJECTIVE: Diverse microorganisms present on the surface of chronic wounds have been established to constitute wound microbiota. The aims of this study were to quantify the viability of wound microbiota, classify dispersal of viable microbes from the wound, and determine if human wound microbiota can produce a chronic wound in an animal model.
METHOD: Wound microbiotas as units (multiple microbial species acting as one infectious agent) were obtained from well-defined human chronic wounds and seeded onto mouse surgical excision wounds to produce chronically infected wounds that closely resembled the chronic wounds observed in the original hosts.
RESULTS: We found the wound microbiota harvested from 35 out of 43 (81%) patients could produce similar chronic wounds (producing slough and exudate) in a murine chronic wound model. The top 30 species present in patient wounds were identified in the mouse wounds by molecular sequencing. Koch's postulates could therefore be applied to establish wound microbiota as the cause of the original human chronic wound infections. Evidence-based medicine criteria such as Hill's criteria for causation can all be satisfied by what is currently known about wound microbiota.
CONCLUSION: This study demonstrates that wound microbiota actively disseminates from the chronic wound by forces and mechanisms intrinsic to the wound. Koch's postulates and Hill's criteria for causation together suggest chronic wound microbiota to be the main cause underlying the pathogenesis of chronic wounds. DECLARATION OF INTEREST: RW has an equity interest in PathoGenius Labs. No funding was received for this study.