Macro-Scale Spatial Variation in Chronic Wound Microbiota: A Cross-Sectional Study

摘要

Controlling for sample site is considered to be an important aspect of chronic wound microbiological investigations; yet, macro-scale spatial variation in wound microbiota has not been well characterized. A total of 31 curette samples were collected at the leading edge, opposing leading edge and/or center of 13 chronic wounds. Bacterial community composition was characterized using a combination of 16S rRNA gene based pyrosequencing; heat map display; hierarchical clustering; non-metric multidimensional scaling; and permutation multivariate analysis of variance. A total of 58 bacterial families and 91 bacterial genera were characterized among the 13 wounds. While substantial macro-scale spatial variation was observed among the wounds, bacterial communities at different sites within individual wounds were significantly more similar than those in different wounds (p = 0.001). Our results support the prevalent opinion that controlling for sample site may improve the quality of wound microbiota studies; however, the significant similarity in bacterial communities from different sites within individual wounds indicates that studies failing to control for sampling site should not be disregarded based solely on this criterion. A composite sample from multiple sites across the surface of individual wounds may provide the most robust characterization of wound microbiota.