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Md A Nahid,1 Jaclyn M Griffin,2 Michael B Lustik,3 Jordan J Hayes,3 Keith SK Fong,3 Timothy S Horseman,3 Massimo Menguito,4 Erik C Snesrud5 ,† Jason C Barnhill,4,6 Michael A Washington4 1Department of Dental and Craniomaxillofacial Trauma Research, United States Army Institute of Surgical Research, JBSA Fort Sam, Houston, TX 78234, USA; 2Department of Vascular Surgery, Tripler Army Medical Center, Honolulu, HI, 96859, USA; 3Department of Clinical Investigation, Tripler Army Medical Center, Honolulu, HI 96859, USA; 4Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA; 5Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA; 6Department of Radiology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA†Dr Erik C Snesrud passed away on February 10, 2020Correspondence: Md A NahidUnited States Army Institute of Surgical Research, JBSA Fort Sam, Houston, TX 78234, USATel +1 210-539-6419Fax +1 210-539-3877Email md.a.nahid.mil@mail.milPurpose: The biology of chronic wounds is complex and many factors act concurrently to impede healing progress. In this study, the dynamics of microflora changes and their antibiotic susceptibility patterns were evaluated longitudinally over 30 days using data from 28 patients with a total of 47 chronic lower extremity wounds.Materials and Methods: In this study, colonized wound isolates were characterized using cultural, biochemical, and VITEK 2 methods. Antibiotic susceptibility patterns of the wound isolates were analyzed using various phenotypic assays. Furthermore, antimicrobial resistance patterns and the presence of mutations were evaluated by a genotypic assay, whole-genome sequencing (WGS).Results: Staphylococcus aureus and Pseudomonas aeruginosa were found to be the most common strains at early time points, while members of Enterobacteriaceae were prevalent at later stages of infection. Antimicrobial resistance testing and whole-genome sequencing revealed that the molecular and phenotypic characteristics of the identified wound pathogens remained relatively stable throughout the study period. It was also noted that Enterobacter and Klebsiella species may serve as reservoirs for quinolone resistance in the Pacific region.Conclusion: Our observations showed that wounds were colonized with diverse bacteria and interestingly their numbers and/or types were changed over the course of infection. The rapid genetic changes that accompanied the first 4 weeks after presentation did not directly contribute to the development of antibiotic resistance. In addition, standard wound care procedures did not appear to select for resistant bacterial strains. Future efforts should focus on defining those genetic changes associated with the wound colonizing microorganisms that occur beyond 4 weeks.Keywords: anti-microbial resistance, antimicrobial susceptibility profiling, non-healing wound, wound microflora, wound healing

Background: Female Servicemembers are increasingly being incorporated into the combat arms and Special Operations communities. Female urinary diversion devices (FUDDs) have been used to facilitate urination in the austere environments that are encountered by Servicemembers. Importantly, the potential for the bacterial contamination of these devices has not been evaluated. The goals of this study were to determine whether microorganisms adhere to the surfaces of FUDDs in the field environment and to demonstrate the presence of potential pathogens on the used devices., Materials and Methods: A total of 15 devices that were used in a comprehensive 18-24-hour military field exercise were tested for the presence of microorganisms. Briefly, each device was swabbed, and the swabs were used to inoculate blood agar plates to encourage bacterial growth. The resulting bacterial colonies were identified, and the surface topography of the devices was investigated with electron microscopy., Results: Although microscopy revealed few surface features capable of facilitating bacterial attachment, several species were recovered. Significantly, a biofilm-forming strain of Proteus mirabilis (P. mirabilis) was detected on two of the devices. P. mirabilis is a mobile urinary pathogen that can potentially migrate from the surface of the device into the urinary tract of the user., Conclusion: Commercial FUDDs can support bacterial growth and harbor potential pathogens. Care should be taken to ensure that Servicemembers are aware of the importance of the proper care and cleaning of these devices in the field environment. To this end, standard operating procedures should be developed and distributed., (2021.)