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Pham E, Reynolds-Reber L, Navarro S, Hamood A, Jones-Donaldson LM, Smith AC. Determination of the Course of Cyan Fluorescence of Pseudomonas aeruginosa with a Handheld Bacterial Imaging Device. Diagnostics (Basel) 2024; 14:1474. [PMID: 39061611 PMCID: PMC11276341 DOI: 10.3390/diagnostics14141474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 06/11/2024] [Accepted: 06/23/2024] [Indexed: 07/28/2024] Open
Abstract
Chronic wound infections are of clinical concern as they often lead to high rates of mortality and morbidity. A point-of-care handheld bacterial fluorescence imaging has been designed to detect the auto-fluorescent characteristics of most clinically relevant species of bacteria. This device causes most species of bacteria to exhibit red fluorescence due to the production of exoproduct porphyrins. One of the most significant contributors to the pathogenicity of chronic wounds is the pathogen Pseudomonas aeruginosa, and interestingly, this organism exhibits an additional unique cyan fluorescence signature. There is an over 90% positive predictive value that, when a chronic wound exhibits cyan fluorescence with the bacterial fluorescence imaging device, the wound will harbor P. aeruginosa. This project seeks to understand what genetic factor(s) contribute to the cyan phenotype observed.
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Affiliation(s)
- Emily Pham
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409, USA;
| | | | - Stephany Navarro
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.N.); (A.H.)
| | - Abdul Hamood
- Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; (S.N.); (A.H.)
| | | | - Allie Clinton Smith
- Department of Honors Studies, Texas Tech University, Lubbpock, TX 79409, USA
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2
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Chmykh Y, Nadeau JL. The use of fluorescence lifetime imaging (FLIM) for in situ microbial detection in complex mineral substrates. J Microsc 2024; 294:36-51. [PMID: 38230460 DOI: 10.1111/jmi.13264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 12/16/2023] [Accepted: 01/09/2024] [Indexed: 01/18/2024]
Abstract
The utility of fluorescence lifetime imaging microscopy (FLIM) for identifying bacteria in complex mineral matrices was investigated. Baseline signals from unlabelled Bacillus subtilis and Euglena gracilis, and Bacillus subtilis labelled with SYTO 9 were obtained using two-photon excitation at 730, 750 and 800 nm, identifying characteristic lifetimes of photosynthetic pigments, unpigmented cellular autofluorescence, and SYTO 9. Labelled and unlabelled B. subtilis were seeded onto marble and gypsum samples containing endolithic photosynthetic cyanobacteria and the ability to distinguish cells from mineral autofluorescence and nonspecific dye staining was examined in parallel with ordinary multichannel confocal imaging. It was found that FLIM enabled discrimination of SYTO 9 labelled cells from background, but that the lifetime of SYTO 9 was shorter in cells on minerals than in pure culture under our conditions. Photosynthetic microorganisms were easily observed using both FLIM and confocal. Unlabelled, nonpigmented bacteria showed weak signals that were difficult to distinguish from background when minerals were present, though cellular autofluorescence consistent with NAD(P)H could be seen in pure cultures, and phasor analysis permitted detection on rocks. Gypsum and marble samples showed similar autofluorescence profiles, with little autofluorescence in the yellow-to-red range. Lifetime or time-gated imaging may prove a useful tool for environmental microbiology. LAY DESCRIPTION: The standard method of bacterial enumeration is to label the cells with a fluorescent dye and count them under high-power fluorescence microscopy. However, this can be difficult when the cells are embedded in soil and rock due to fluorescence from the surrounding minerals and dye binding to ambiguous features of the substrate. The use of fluorescence lifetime imaging (FLIM) can disambiguate these signals and allow for improved detection of bacteria in environmental samples.
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Affiliation(s)
- Yekaterina Chmykh
- Department of Physics, Portland State University, Portland, Oregon, USA
| | - Jay L Nadeau
- Department of Physics, Portland State University, Portland, Oregon, USA
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Case N, Johnston N, Nadeau J. Fluorescence Microscopy with Deep UV, Near UV, and Visible Excitation for In Situ Detection of Microorganisms. ASTROBIOLOGY 2024; 24:300-317. [PMID: 38507693 PMCID: PMC10979697 DOI: 10.1089/ast.2023.0020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 01/02/2024] [Indexed: 03/22/2024]
Abstract
We report a simple, inexpensive design of a fluorescence microscope with light-emitting diode (LED) excitation for detection of labeled and unlabeled microorganisms in mineral substrates. The use of deep UV (DUV) excitation with visible emission requires no specialized optics or slides and can be implemented easily and inexpensively using an oblique illumination geometry. DUV excitation (<280 nm) is preferable to near UV (365 nm) for avoidance of mineral autofluorescence. When excited with DUV, unpigmented bacteria show two emission peaks: one in the near UV ∼320 nm, corresponding to proteins, and another peak in the blue to green range, corresponding to flavins and/or reduced nicotinamide adenine dinucleotide (NADH). Many commonly used dyes also show secondary excitation peaks in the DUV, with identical emission spectra and quantum yields as their primary peak. However, DUV fails to excite key biosignature molecules, especially chlorophyll in cyanobacteria. Visible excitation (violet to blue) also results in less mineral autofluorescence than near UV, and most autofluorescence in the minerals seen here is green, so that red dyes and red autofluorescence of chlorophyll and porphyrins are readily distinguished. The pairing of DUV and near UV or visible excitation, with emission across the visible, represents the most thorough approach to detection of labeled and unlabeled bacteria in soil and rock.
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Affiliation(s)
- Noel Case
- Department of Physics, Portland State University, Portland, Oregon, USA
| | - Nikki Johnston
- Department of Physics, Portland State University, Portland, Oregon, USA
| | - Jay Nadeau
- Department of Physics, Portland State University, Portland, Oregon, USA
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Huang SW, Wu YF, Ahmed T, Pan SC, Cheng CM. Point-of-care detection devices for wound care and monitoring. Trends Biotechnol 2024; 42:74-90. [PMID: 37563037 DOI: 10.1016/j.tibtech.2023.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/01/2023] [Accepted: 07/05/2023] [Indexed: 08/12/2023]
Abstract
Healthcare resources are heavily burdened by infections that impede the wound-healing process. A wide range of advanced technologies have been developed for detecting and quantifying infection biomarkers. Finding a timely, accurate, non-invasive diagnostic alternative that does not require a high level of training is a critical step toward arresting common clinical patterns of wound health decline. There is growing interest in the development of innovative diagnostics utilizing a variety of emerging technologies, and new biomarkers have been investigated as potential indicators of wound infection. In this review, we summarize diagnostics available for wound infection, including those used in clinics and still under development.
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Affiliation(s)
- Shu-Wei Huang
- Department of Orthopedic Surgery, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Yu-Feng Wu
- Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu, Taiwan; Division of Plastic Surgery, Department of Surgery, National Taiwan University Hospital, Hsin-Chu Branch, Hsinchu, Taiwan; International Intercollegiate PhD Program, National Tsing Hua University, Hsinchu, Taiwan
| | - Tanvir Ahmed
- Department of Food Engineering and Tea Technology, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Shin-Chen Pan
- Department of Surgery, Section of Plastic and Reconstructive Surgery, National Cheng Kung University Hospital, College of Medicine, International Center for Wound Repair and Regeneration, National Cheng Kung University, Tainan, Taiwan.
| | - Chao-Min Cheng
- Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu, Taiwan.
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5
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Okebiorun M, Oberbeck C, Waite C, Clark S, Miller D, Barney Smith EH, Cornell KA, Browning J. Selective Optical Imaging for Detection of Bacterial Biofilms in Tissues. J Imaging 2023; 9:160. [PMID: 37623692 PMCID: PMC10455256 DOI: 10.3390/jimaging9080160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/28/2023] [Accepted: 08/10/2023] [Indexed: 08/26/2023] Open
Abstract
SIGNIFICANCE The development of an imaging technique to accurately identify biofilm regions on tissues and in wounds is crucial for the implementation of precise surface-based treatments, leading to better patient outcomes and reduced chances of infection. AIM The goal of this study was to develop an imaging technique that relies on selective trypan blue (TB) staining of dead cells, necrotic tissues, and bacterial biofilms, to identify biofilm regions on tissues and wounds. APPROACH The study explored combinations of ambient multi-colored LED lights to obtain maximum differentiation between stained biofilm regions and the underlying chicken tissue or glass substrate during image acquisition. The TB imaging results were then visually and statistically compared to fluorescence images using a shape similarity measure. RESULTS The comparisons between the proposed TB staining method and the fluorescence standard used to detect biofilms on tissues and glass substrates showed up to 97 percent similarity, suggesting that the TB staining method is a promising technique for identifying biofilm regions. CONCLUSIONS The TB staining method demonstrates significant potential as an effective imaging technique for the identification of fluorescing and non-fluorescing biofilms on tissues and in wounds. This approach could lead to improved precision in surface-based treatments and better patient outcomes.
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Affiliation(s)
- Michael Okebiorun
- Biomedical Engineering Program, Boise State University, Boise, ID 83725, USA;
| | - Cody Oberbeck
- Department of Electrical and Computer Engineering, Boise State University, Boise, ID 83725, USA or (E.H.B.S.)
| | - Cameron Waite
- Department of Mechanical and Biomedical Engineering, Boise State University, Boise, ID 83725, USA
| | - Samuel Clark
- Department of Mathematics, Boise State University, Boise, ID 83725, USA
| | - Dalton Miller
- Department of Chemistry and Biochemistry, Boise State University, Boise, ID 83725, USA (K.A.C.)
| | - Elisa H. Barney Smith
- Department of Electrical and Computer Engineering, Boise State University, Boise, ID 83725, USA or (E.H.B.S.)
- Autonomous Systems and Software Program, Luleå Tekniska Universitet, 97187 Luleå, Sweden
| | - Kenneth A. Cornell
- Department of Chemistry and Biochemistry, Boise State University, Boise, ID 83725, USA (K.A.C.)
| | - Jim Browning
- Department of Electrical and Computer Engineering, Boise State University, Boise, ID 83725, USA or (E.H.B.S.)
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Weigelt MA, Lev-Tov HA, Tomic-Canic M, Lee WD, Williams R, Strasfeld D, Kirsner RS, Herman IM. Advanced Wound Diagnostics: Toward Transforming Wound Care into Precision Medicine. Adv Wound Care (New Rochelle) 2022; 11:330-359. [PMID: 34128387 PMCID: PMC8982127 DOI: 10.1089/wound.2020.1319] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 05/29/2021] [Indexed: 11/01/2022] Open
Abstract
Significance: Nonhealing wounds are an ever-growing global pandemic, with mortality rates and management costs exceeding many common cancers. Although our understanding of the molecular and cellular factors driving wound healing continues to grow, standards for diagnosing and evaluating wounds remain largely subjective and experiential, whereas therapeutic strategies fail to consistently achieve closure and clinicians are challenged to deliver individualized care protocols. There is a need to apply precision medicine practices to wound care by developing evidence-based approaches, which are predictive, prescriptive, and personalized. Recent Advances: Recent developments in "advanced" wound diagnostics, namely biomarkers (proteases, acute phase reactants, volatile emissions, and more) and imaging systems (ultrasound, autofluorescence, spectral imaging, and optical coherence tomography), have begun to revolutionize our understanding of the molecular wound landscape and usher in a modern age of therapeutic strategies. Herein, biomarkers and imaging systems with the greatest evidence to support their potential clinical utility are reviewed. Critical Issues: Although many potential biomarkers have been identified and several imaging systems have been or are being developed, more high-quality randomized controlled trials are necessary to elucidate the currently questionable role that these tools are playing in altering healing dynamics or predicting wound closure within the clinical setting. Future Directions: The literature supports the need for the development of effective point-of-care wound assessment tools, such as a platform diagnostic array that is capable of measuring multiple biomarkers at once. These, along with advances in telemedicine, synthetic biology, and "smart" wearables, will pave the way for the transformation of wound care into a precision medicine. Clinical Trial Registration number: NCT03148977.
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Affiliation(s)
- Maximillian A. Weigelt
- Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Hadar A. Lev-Tov
- Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Marjana Tomic-Canic
- Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - W. David Lee
- Precision Healing, Inc., Newton, Massachusetts, USA
| | | | | | - Robert S. Kirsner
- Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Ira M. Herman
- Precision Healing, Inc., Newton, Massachusetts, USA
- Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
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Wu YF, Lin YC, Yang HW, Cheng NC, Cheng CM. Point-of-Care Wound Blotting with Alcian Blue Grading versus Fluorescence Imaging for Biofilm Detection and Predicting 90-Day Healing Outcomes. Biomedicines 2022; 10:biomedicines10051200. [PMID: 35625936 PMCID: PMC9138671 DOI: 10.3390/biomedicines10051200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/16/2022] Open
Abstract
Biofilm infection has been identified as a crucial factor of the pathogenesis of chronic wound, but wound biofilm diagnosis remains as an unmet clinical need. We previously proposed a modified wound blotting technique using Alcian blue staining for biofilm detection that was characterized as being non-invasive, time-saving, non-expansive, and informative for biofilm distribution. In this study, we adapted a novel Alcian blue grading method as the severity of biofilm infection for the wound blotting technique and compared its biofilm detection efficacy with MolecuLight i:X- a point-of-care florescence imaging device to detect bacteria and biofilm in wounds. Moreover, their predictive value of complete wound healing at 90 days was analyzed. When validated with wound culture results in the 53 enrolled subjects with chronic wounds, the modified wound blotting method showed a strong association with wound culture, while MolecuLight i:X only exhibited a weak association. In predicting 90-day wound outcomes, the modified wound blotting method showed a strong association (Kendall’s tau value = 0.563, p < 0.001), and the wound culture showed a moderate association (Spearman’s rho = 0.535, p < 0.001), but MolecuLight i:X exhibited no significant association (p = 0.184). In this study, modified wound blotting with the Alcian blue grading method showed superior value to MolecuLight i:X both in biofilm detection and predictive validity in 90-day wound-healing outcomes.
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Affiliation(s)
- Yu-Feng Wu
- Division of Plastic Surgery, Department of Surgery, National Taiwan University Hospital, Hsin-Chu Branch, Hsinchu 300, Taiwan;
- Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan;
| | - Yu-Chen Lin
- Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan;
| | - Hung-Wei Yang
- Division of Plastic Surgery, Department of Surgery, National Taiwan University Hospital, Biomedical Park Branch, Zhubei City 302, Taiwan;
| | - Nai-Chen Cheng
- Division of Plastic Surgery, Department of Surgery, National Taiwan University Hospital and College of Medicine, Taipei 100, Taiwan
- Correspondence: (N.-C.C.); (C.-M.C.)
| | - Chao-Min Cheng
- Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan;
- Correspondence: (N.-C.C.); (C.-M.C.)
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8
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Li Y, Hu Y, Chen T, Chen Y, Li Y, Zhou H, Yang D. Advanced detection and sensing strategies of Pseudomonas aeruginosa and quorum sensing biomarkers: A review. Talanta 2022; 240:123210. [PMID: 35026633 DOI: 10.1016/j.talanta.2022.123210] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 12/31/2021] [Accepted: 01/04/2022] [Indexed: 11/25/2022]
Abstract
Pseudomonas aeruginosa (P. aeruginosa), a ubiquitous opportunistic pathogen, can frequently cause chronic obstructive pulmonary disease, cystic fibrosis and chronic wounds, and potentially lead to severe morbidity and mortality. Timely and adequate treatment of nosocomial infection in clinic depends on rapid detection and accurate identification of P. aeruginosa and its early-stage antibiotic susceptibility test. Traditional methods like plating culture, polymerase chain reaction, and enzyme-linked immune sorbent assays are time-consuming and require expensive equipment, limiting the rapid diagnostic application. Advanced sensing strategy capable of fast, sensitive and simple detection with low cost has therefore become highly desired in point of care testing (POCT) of nosocomial pathogens. Within this review, advanced detection and sensing strategies for P. aeruginosa cells along with associated quorum sensing (QS) molecules over the last ten years are discussed and summarized. Firstly, the principles of four commonly used sensing strategies including localized surface plasmon resonance (LSPR), surface-enhanced Raman spectroscopy (SERS), electrochemistry, and fluorescence are briefly overviewed. Then, the advancement of the above sensing techniques for P. aeruginosa cells and its QS biomarkers detection are introduced, respectively. In addition, the integration with novel compatible platforms towards clinical application is highlighted in each section. Finally, the current achievements are summarized along with proposed challenges and prospects.
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Affiliation(s)
- Yingying Li
- The Affiliated Hospital of Medical School, Ningbo University, Ningbo, Zhejiang Province, 315211, People's Republic of China; Department of Preventative Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China
| | - Yang Hu
- Department of Preventative Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China
| | - Tao Chen
- Department of Preventative Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China
| | - Yan Chen
- Department of Preventative Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China
| | - Yi Li
- Graduate School of Biomedical Engineering and ARC Centre of Excellence in Nanoscale Biophotonics, University of New South Wales, Sydney, 2052, Australia
| | - Haibo Zhou
- College of Pharmacy, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Danting Yang
- The Affiliated Hospital of Medical School, Ningbo University, Ningbo, Zhejiang Province, 315211, People's Republic of China; Department of Preventative Medicine, Zhejiang Key Laboratory of Pathophysiology, School of Medicine, Ningbo University, 818 Fenghua Road, Ningbo, Zhejiang Province, 315211, People's Republic of China.
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9
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Johnson AC, Buchanan EP, Khechoyan DY. Wound infection: A review of qualitative and quantitative assessment modalities. J Plast Reconstr Aesthet Surg 2021; 75:1287-1296. [PMID: 35216936 DOI: 10.1016/j.bjps.2021.11.060] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 05/26/2021] [Accepted: 11/12/2021] [Indexed: 12/20/2022]
Abstract
Surgical site infections (SSI) and chronic wounds represent a burden to patients and the health care system. One in 24 surgical patients will develop an SSI, making SSI the most common nosocomial infection in the USA. Early detection and monitoring of wound infection are critical for timely healing and return to normal function. However, the mainstay of wound infection diagnostic entails subjective clinical examination and semi-quantitative, invasive microbiological tests. In this review, we present current wound infection assessment modalities in the clinical and translational fields. There is a need for a point-of-care assessment tool that provides fast, accurate, and quantitative information on wound status, with minimal to no contact with the patient. In the next ten years, the evolution of wound diagnostic tools reported here may allow medical providers to optimize patient care while minimizing patient discomfort.
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Affiliation(s)
- Ariel C Johnson
- Division of Plastic and Reconstructive Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Edward P Buchanan
- Division of Plastic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX, USA; Division of Plastic Surgery, Department of Surgery, Texas Children's Hospital, Houston, TX, USA
| | - David Y Khechoyan
- Department of Pediatric Plastic Surgery, Children's Hospital Colorado, Aurora, CO, USA.
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Raizman R, Little W, Smith AC. Rapid Diagnosis of Pseudomonas aeruginosa in Wounds with Point-Of-Care Fluorescence Imaing. Diagnostics (Basel) 2021; 11:diagnostics11020280. [PMID: 33670266 PMCID: PMC7917920 DOI: 10.3390/diagnostics11020280] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/06/2021] [Accepted: 02/09/2021] [Indexed: 01/14/2023] Open
Abstract
Pseudomonas aeruginosa (PA) is a common bacterial pathogen in chronic wounds known for its propensity to form biofilms and evade conventional treatment methods. Early detection of PA in wounds is critical to the mitigation of more severe wound outcomes. Point-of-care bacterial fluorescence imaging illuminates wounds with safe, violet light, triggering the production of cyan fluorescence from PA. A prospective single blind clinical study was conducted to determine the positive predictive value (PPV) of cyan fluorescence for the detection of PA in wounds. Bacterial fluorescence using the MolecuLight i:X imaging device revealed cyan fluorescence signal in 28 chronic wounds, including venous leg ulcers, surgical wounds, diabetic foot ulcers and other wound types. To correlate the cyan signal to the presence of PA, wound regions positive for cyan fluorescence were sampled via curettage. A semi-quantitative culture analysis of curettage samples confirmed the presence of PA in 26/28 wounds, resulting in a PPV of 92.9%. The bacterial load of PA from cyan-positive regions ranged from light to heavy. Less than 20% of wounds that were positive for PA exhibited the classic symptoms of PA infection. These findings suggest that cyan detected on fluorescence images can be used to reliably predict bacteria, specifically PA at the point-of-care.
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Affiliation(s)
- Rose Raizman
- Department of Professional Practice, Scarborough Health Network, Lawrence S. Bloomberg Faculty of Nursing, University of Toronto, Toronto, ON M1E 4B9, Canada
- Correspondence: ; Tel.: +1-416-886-2328
| | - William Little
- Department of Honors Studies, Texas Tech University, Lubbock, TX 79409, USA; (W.L.); (A.C.S.)
| | - Allie Clinton Smith
- Department of Honors Studies, Texas Tech University, Lubbock, TX 79409, USA; (W.L.); (A.C.S.)
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