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bioRxiv · 10.1101/614917

Evaluation of Bacteria Detected in Both Urine and Open Wounds in Nursing Facility Residents

Abstract

Nursing home residents are at a greater risk of developing pressure injuries that develop into an open wound. Open wounds can be colonized with bacteria from multiple sources. Emerging evidence suggests the specific composition of the open wound microbial community can result in delayed wound healing and increased infection risk. Understanding the factors that influence microbial colonization of open wounds, can lead to the prevention of infections. The relationship between bacteria found in urine and that of open wounds, is currently unknown. Recent studies have shown that nursing home residents can harbor a urinary microbiota independent of symptoms and frequently experience urinary incontinence. To determine if the colonization of open wounds mirrors urinary colonization, we conducted a pilot study with nursing home residents, comparing bacteria present in open pressure injuries below the umbilicus and urine. To identify microbial species that were present in both urine and open wound at one timepoint, standard bacteriologic culture techniques followed by MALDI-TOF was used as well as16S rRNA-encoding gene amplicon sequencing. In this study we found that some bacteria detected in urine were also detected in open wounds in one individual at one timepoint, using both culture dependent and independent techniques. Bacterial species that were more often detected at both sites included Enterococcus faecalis, Proteus mirabilis, Escherichia coli, and Providencia stuartii. This pilot study provides evidence that urinary colonization can mirror open wound colonization. Further studies are needed to investigate if parallel colonization of these anatomical sites affect infection outcomes.

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Libertucci, J., Bassis, C., Cassone, M., Gibson, K. E., Lansing, B., Mody, L., Young, V. B., Meddings, J.. 2019-04-22. Evaluation of Bacteria Detected in Both Urine and Open Wounds in Nursing Facility Residents. https://doi.org/10.1101/614917

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