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Chand S, Rrapi R, Gabel CK, Song S, Shah R, El Saleeby C, Kroshinsky D. Groin and buttocks involvement and methicillin-resistant Staphylococcus aureus nasal swab independently predict cutaneous abscess and methicillin-resistant Staphylococcus aureus infection in inpatient pediatric cellulitis: A retrospective cohort study. J Am Acad Dermatol 2022; 87:1205-1207. [PMID: 35288201 DOI: 10.1016/j.jaad.2022.02.065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 01/27/2022] [Accepted: 02/22/2022] [Indexed: 11/27/2022]
Affiliation(s)
- Sidharth Chand
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts
| | - Renajd Rrapi
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts
| | - Colleen K Gabel
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts
| | - Sarah Song
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts
| | - Radhika Shah
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts
| | - Chadi El Saleeby
- Department of Pediatrics, Divisions of Hospital Medicine and Infectious Disease, Massachusetts General Hospital for Children, Boston, Massachusetts
| | - Daniela Kroshinsky
- Department of Dermatology, Massachusetts General Hospital, Boston, Massachusetts.
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2
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Copin R, Sause WE, Fulmer Y, Balasubramanian D, Dyzenhaus S, Ahmed JM, Kumar K, Lees J, Stachel A, Fisher JC, Drlica K, Phillips M, Weiser JN, Planet PJ, Uhlemann AC, Altman DR, Sebra R, van Bakel H, Lighter J, Torres VJ, Shopsin B. Sequential evolution of virulence and resistance during clonal spread of community-acquired methicillin-resistant Staphylococcus aureus. Proc Natl Acad Sci U S A 2019; 116:1745-1754. [PMID: 30635416 PMCID: PMC6358666 DOI: 10.1073/pnas.1814265116] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The past two decades have witnessed an alarming expansion of staphylococcal disease caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). The factors underlying the epidemic expansion of CA-MRSA lineages such as USA300, the predominant CA-MRSA clone in the United States, are largely unknown. Previously described virulence and antimicrobial resistance genes that promote the dissemination of CA-MRSA are carried by mobile genetic elements, including phages and plasmids. Here, we used high-resolution genomics and experimental infections to characterize the evolution of a USA300 variant plaguing a patient population at increased risk of infection to understand the mechanisms underlying the emergence of genetic elements that facilitate clonal spread of the pathogen. Genetic analyses provided conclusive evidence that fitness (manifest as emergence of a dominant clone) changed coincidently with the stepwise emergence of (i) a unique prophage and mutation of the regulator of the pyrimidine nucleotide biosynthetic operon that promoted abscess formation and colonization, respectively, thereby priming the clone for success; and (ii) a unique plasmid that conferred resistance to two topical microbiocides, mupirocin and chlorhexidine, frequently used for decolonization and infection prevention. The resistance plasmid evolved through successive incorporation of DNA elements from non-S. aureus spp. into an indigenous cryptic plasmid, suggesting a mechanism for interspecies genetic exchange that promotes antimicrobial resistance. Collectively, the data suggest that clonal spread in a vulnerable population resulted from extensive clinical intervention and intense selection pressure toward a pathogen lifestyle that involved the evolution of consequential mutations and mobile genetic elements.
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Affiliation(s)
- Richard Copin
- Division of Infectious Diseases and Immunology, Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - William E Sause
- Department of Microbiology, New York University School of Medicine, New York, NY 10016
| | - Yi Fulmer
- Division of Infectious Diseases and Immunology, Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - Divya Balasubramanian
- Department of Microbiology, New York University School of Medicine, New York, NY 10016
| | - Sophie Dyzenhaus
- Department of Microbiology, New York University School of Medicine, New York, NY 10016
| | - Jamil M Ahmed
- Division of Infectious Diseases and Immunology, Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - Krishan Kumar
- Division of Infectious Diseases and Immunology, Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - John Lees
- Department of Microbiology, New York University School of Medicine, New York, NY 10016
| | - Anna Stachel
- Division of Infectious Diseases and Immunology, Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - Jason C Fisher
- Division of Pediatric Surgery, Department of Surgery, New York University School of Medicine, New York, NY 10016
| | - Karl Drlica
- Public Health Research Institute, New Jersey Medical School, Rutgers Biomedical and Health Sciences, Rutgers University, Newark, NJ 07103
- Department of Microbiology, Biochemistry, and Molecular Genetics, New Jersey Medical School, Rutgers Biomedical and Health Sciences, Rutgers University, Newark, NJ 07103
| | - Michael Phillips
- Division of Infectious Diseases and Immunology, Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - Jeffrey N Weiser
- Department of Microbiology, New York University School of Medicine, New York, NY 10016
| | - Paul J Planet
- Department of Pediatric Infectious Disease, Children's Hospital of Philadelphia, Philadelphia, PA 19104
| | - Anne-Catrin Uhlemann
- Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, NY 10032
| | - Deena R Altman
- Division of Infectious Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York City, NY 10029
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Robert Sebra
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Harm van Bakel
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029
| | - Jennifer Lighter
- Division of Pediatric Infectious Diseases, Department of Pediatrics, New York University School of Medicine, New York, NY 10016
| | - Victor J Torres
- Department of Microbiology, New York University School of Medicine, New York, NY 10016;
| | - Bo Shopsin
- Division of Infectious Diseases and Immunology, Department of Medicine, New York University School of Medicine, New York, NY 10016;
- Department of Microbiology, New York University School of Medicine, New York, NY 10016
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3
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Platelets Enhance Dendritic Cell Responses against Staphylococcus aureus through CD40-CD40L. Infect Immun 2018; 86:IAI.00186-18. [PMID: 29914928 DOI: 10.1128/iai.00186-18] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 06/12/2018] [Indexed: 12/24/2022] Open
Abstract
Staphylococcus aureus is a major human pathogen that can cause mild to severe life-threatening infections in many tissues and organs. Platelets are known to participate in protection against S. aureus by direct killing and by enhancing the activities of neutrophils and macrophages in clearing S. aureus infection. Platelets have also been shown to induce monocyte differentiation into dendritic cells and to enhance activation of dendritic cells. Therefore, in the present study, we explored the role of platelets in enhancing bone marrow-derived dendritic cell (BMDC) function against S. aureus We observed a significant increase in dendritic cell phagocytosis and intracellular killing of a methicillin-resistant Staphylococcus aureus (MRSA) strain (USA300) by thrombin-activated platelets or their releasates. Enhancement of bacterial uptake and killing by DCs is mediated by platelet-derived CD40L. Coculture of USA300 and BMDCs in the presence of thrombin-activated platelet releasates invokes upregulation of the maturation marker CD80 on DCs and enhanced production of the proinflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin 12 (IL-12), and IL-6. Overall, these observations support our hypothesis that platelets play a critical role in the host defense against S. aureus infection. Platelets stimulate DCs, leading to direct killing of S. aureus and enhanced DC maturation, potentially leading to adaptive immune responses against S. aureus.
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Gagnaire J, Verhoeven PO, Grattard F, Rigaill J, Lucht F, Pozzetto B, Berthelot P, Botelho-Nevers E. Epidemiology and clinical relevance of Staphylococcus aureus intestinal carriage: a systematic review and meta-analysis. Expert Rev Anti Infect Ther 2017; 15:767-785. [PMID: 28726558 DOI: 10.1080/14787210.2017.1358611] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Recent data highlight the importance of screening more than one site for improving the detection of S. aureus colonization. Intestinal carriage is frequently under-investigated and its clinical impact ought to be defined a better way. Areas covered: This review and meta-analysis provide an updated overview of prevalence, characteristics and clinical significance of S. aureus intestinal carriage in different populations, both for methicillin-susceptible and -resistant S. aureus strains. Expert commentary: Intestinal S. aureus carriage is documented with higher prevalence in children and in patients with S. aureus skin and soft tissue infections. This site of colonization was shown to be associated with a high risk of dissemination in the environment and with S. aureus infection. Intestinal carriage is frequently retrieved in nasal carriers, reflecting probably an association with a high bacterial load. Exclusive intestinal carriage present in one third of intestinal carriers can be associated with infection. Comparative genotyping analysis of different strains from nasal and extra-nasal sites of carriage, including the intestinal ones, in the same individuals, would allow a better comprehension of the pathophysiology of S. aureus endogenous infection. It could also permit to improve the prevention of these infections by decolonization of sites implicated in infection genesis.
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Affiliation(s)
- Julie Gagnaire
- a GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes) , University of Lyon , Saint-Etienne , France.,b Infectious Diseases Department , University Hospital of Saint-Etienne , Saint-Etienne , France
| | - Paul O Verhoeven
- a GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes) , University of Lyon , Saint-Etienne , France.,c Laboratory of Infectious Agents and Hygiene , University Hospital of Saint-Etienne , Saint-Etienne , France
| | - Florence Grattard
- a GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes) , University of Lyon , Saint-Etienne , France.,c Laboratory of Infectious Agents and Hygiene , University Hospital of Saint-Etienne , Saint-Etienne , France
| | - Josselin Rigaill
- a GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes) , University of Lyon , Saint-Etienne , France.,c Laboratory of Infectious Agents and Hygiene , University Hospital of Saint-Etienne , Saint-Etienne , France
| | - Frédéric Lucht
- a GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes) , University of Lyon , Saint-Etienne , France.,b Infectious Diseases Department , University Hospital of Saint-Etienne , Saint-Etienne , France
| | - Bruno Pozzetto
- a GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes) , University of Lyon , Saint-Etienne , France.,c Laboratory of Infectious Agents and Hygiene , University Hospital of Saint-Etienne , Saint-Etienne , France
| | - Philippe Berthelot
- a GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes) , University of Lyon , Saint-Etienne , France.,b Infectious Diseases Department , University Hospital of Saint-Etienne , Saint-Etienne , France.,c Laboratory of Infectious Agents and Hygiene , University Hospital of Saint-Etienne , Saint-Etienne , France
| | - Elisabeth Botelho-Nevers
- a GIMAP EA 3064 (Groupe Immunité des Muqueuses et Agents Pathogènes) , University of Lyon , Saint-Etienne , France.,b Infectious Diseases Department , University Hospital of Saint-Etienne , Saint-Etienne , France
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5
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Ali RA, Wuescher LM, Dona KR, Worth RG. Platelets Mediate Host Defense against Staphylococcus aureus through Direct Bactericidal Activity and by Enhancing Macrophage Activities. THE JOURNAL OF IMMUNOLOGY 2016; 198:344-351. [PMID: 27895175 DOI: 10.4049/jimmunol.1601178] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 10/27/2016] [Indexed: 12/19/2022]
Abstract
Platelets are the chief effector cells in hemostasis. However, recent evidence suggests they have multiple roles in host defense against infection. Reports by us and others showed that platelets functionally contribute to protection against Staphylococcus aureus infection. In the current study, the capacity of mouse platelets to participate in host defense against S. aureus infection was determined by assessing two possibilities. First, we determined the ability of platelets to kill S. aureus directly; and, second, we tested the possibility that platelets enhance macrophage phagocytosis and intracellular killing of S. aureus In this study we report evidence in support of both mechanisms. Platelets effectively killed two different strains of S. aureus. A clinical isolate of methicillin-resistant S. aureus was killed by platelets (>40% killing in 2 h) in a thrombin-dependent manner whereas a methicillin-sensitive strain was killed to equal extent but did not require thrombin. Interestingly, thrombin-stimulated platelets also significantly enhanced peritoneal macrophage phagocytosis of both methicillin-resistant S. aureus and methicillin-sensitive S. aureus by >70%, and restricted intracellular growth by >40%. Enhancement of macrophage anti-S. aureus activities is independent of contact with platelets but is mediated through releasable products, namely IL-1β. These data confirm our hypothesis that platelets participate in host defense against S. aureus both through direct killing of S. aureus and enhancing the antimicrobial function of macrophages in protection against S. aureus infection.
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Affiliation(s)
- Ramadan A Ali
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614
| | - Leah M Wuescher
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614
| | - Keith R Dona
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614
| | - Randall G Worth
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614
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6
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Sutter DE, Milburn E, Chukwuma U, Dzialowy N, Maranich AM, Hospenthal DR. Changing Susceptibility of Staphylococcus aureus in a US Pediatric Population. Pediatrics 2016; 137:peds.2015-3099. [PMID: 26933211 DOI: 10.1542/peds.2015-3099] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/18/2015] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Staphylococcus aureus is a major cause of infection in both adult and pediatric populations. After several decades of increasing prevalence, the proportion of S aureus infections due to methicillin-resistant S aureus has been reported to be in decline in adults. Data for similar changes in pediatric populations are limited. METHODS Evaluation of S aureus susceptibility data for pediatric patients receiving care in the US Military Health System was performed. Microbiology and demographic data were collected for years 2005 through 2014. Trends in antibiotic susceptibility results were evaluated. Clinical and demographic characteristics were explored to assess for association with antibiotic susceptibilities. RESULTS In this study, 41 745 S aureus isolates from 39 207 pediatric patients were included. An overall increase in susceptibility of isolates to oxacillin was noted over this 10-year period; with over 60% of isolates oxacillin-susceptible in 2014. S aureus susceptibility to clindamycin declined over the study period; notably methicillin-susceptible S aureus susceptibility to clindamycin declined from 90% to 83% (P < .0001). Differences in oxacillin susceptibility between US regions decreased over time. CONCLUSIONS Similar to recent trends seen in adults, the proportion of pediatric S aureus infections secondary to methicillin-resistant S aureus appear to be decreasing, as is variability in US geographical resistance rates. Increasing clindamycin resistance among methicillin-susceptible S aureus should raise caution in the use of empirical clindamycin in presumed S aureus infection. Clinicians should be aware of regional susceptibility patterns when choosing empirical regimens.
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Affiliation(s)
- Deena E Sutter
- Department of Pediatrics, San Antonio Military Medical Center, Fort Sam Houston, Texas;
| | - Emma Milburn
- EpiData Center Department Navy and Marine Corps Public Health Center, Portsmouth, Virginia
| | - Uzo Chukwuma
- EpiData Center Department Navy and Marine Corps Public Health Center, Portsmouth, Virginia
| | - Nicole Dzialowy
- Communicable Disease Branch North Carolina, Department of Health and Human Services, Raleigh, North Carolina; and
| | - Ashley M Maranich
- EpiData Center Department Navy and Marine Corps Public Health Center, Portsmouth, Virginia
| | - Duane R Hospenthal
- Department of Medicine, University of Texas Health Sciences Center, San Antonio, Texas
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7
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Meyer Sauteur PM, Leimer N, Chan PK, Relly C, Seidl K, Zinkernagel AS, Berger C. Methicillin-resistant Staphylococcus aureus eradication in young infants should include the diaper area and treat housing contacts. Acta Paediatr 2015; 104:e581-4. [PMID: 26341723 DOI: 10.1111/apa.13179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/27/2015] [Accepted: 09/01/2015] [Indexed: 12/01/2022]
Affiliation(s)
- Patrick M. Meyer Sauteur
- Division of Infectious Diseases and Hospital Epidemiology, and Children's Research Center (CRC); University Children's Hospital of Zurich; University of Zurich; Zurich Switzerland
| | - Nadja Leimer
- Division of Infectious Diseases and Hospital Epidemiology; University Hospital and University of Zurich; University of Zurich; Zurich Switzerland
| | - Pik Ki Chan
- Division of Infectious Diseases and Hospital Epidemiology, and Children's Research Center (CRC); University Children's Hospital of Zurich; University of Zurich; Zurich Switzerland
| | - Christa Relly
- Division of Infectious Diseases and Hospital Epidemiology, and Children's Research Center (CRC); University Children's Hospital of Zurich; University of Zurich; Zurich Switzerland
| | - Kati Seidl
- Division of Infectious Diseases and Hospital Epidemiology; University Hospital and University of Zurich; University of Zurich; Zurich Switzerland
| | - Annelies S. Zinkernagel
- Division of Infectious Diseases and Hospital Epidemiology; University Hospital and University of Zurich; University of Zurich; Zurich Switzerland
| | - Christoph Berger
- Division of Infectious Diseases and Hospital Epidemiology, and Children's Research Center (CRC); University Children's Hospital of Zurich; University of Zurich; Zurich Switzerland
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Bumah VV, Masson-Meyers DS, Enwemeka CS. Blue 470 nm light suppresses the growth of Salmonella enterica
and methicillin-resistant Staphylococcus aureus
(MRSA) in vitro. Lasers Surg Med 2015; 47:595-601. [DOI: 10.1002/lsm.22385] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/04/2015] [Indexed: 12/23/2022]
Affiliation(s)
- Violet V. Bumah
- College of Health Sciences; University of Wisconsin-Milwaukee; Milwaukee Wisconsin 53211
| | | | - Chukuka S. Enwemeka
- College of Health Sciences; University of Wisconsin-Milwaukee; Milwaukee Wisconsin 53211
- San Diego State University; San Diego; California 92182
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9
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Bumah VV, Whelan HT, Masson-Meyers DS, Quirk B, Buchmann E, Enwemeka CS. The bactericidal effect of 470-nm light and hyperbaric oxygen on methicillin-resistant Staphylococcus aureus (MRSA). Lasers Med Sci 2015; 30:1153-9. [PMID: 25700768 DOI: 10.1007/s10103-015-1722-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 02/09/2015] [Indexed: 01/07/2023]
Abstract
It has been shown that, in vitro, hyperbaric oxygen (HBO) suppresses 28 % bacterial growth, while 470-nm blue light alone suppresses up to 92 % methicillin-resistant Staphylococcus aureus (MRSA) in one application in vitro. Therefore, we determined if combined 470-nm light (55 J/cm(2)) and HBO will yield 100 % bacterial suppression in experimental simulation of mild, moderate or severe MRSA infection. We cultured MRSA at 3 × 10(6), 5 × 10(6), 7 × 10(6), 8 × 10(6), or 12 × 10(6) CFU/ml and treated each concentration in four groups as follows: (1) control (no treatment) (2) photo-irradiation only, (3) photo-irradiation then HBO, (4) HBO only, and (5) HBO then photo-irradiation. Bacteria colonies were then quantified. The results showed that at each bacterial concentration, HBO alone was significantly less effective in suppressing MRSA than photo-irradiation or combined HBO and photo-irradiation (p < 0.0001). Similarly, at no bacterial concentration did combined HBO and 470-nm light treatment yield a statistically better result than 470-nm light alone (p > 0.05), neither did HBO treatment either before or after irradiation make a difference. Furthermore, at no bacterial concentration was 100 % MRSA suppression achieved. Indeed, the maximum bacterial suppression attained was in the mild infection model (3 × 10(6) CFU/ml), with blue light producing 97.3 ± 0.2 % suppression and HBO + 55 J/cm(2) yielding 97.5 ± 2.5 % suppression. We conclude that (1) HBO and 470-nm light individually suppress MRSA growth; (2) 470-nm blue light is more effective in suppressing MRSA than HBO; and (3) HBO did not act synergistically to heighten the bactericidal effect of 470-nm light.
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Affiliation(s)
- Violet Vakunseh Bumah
- College of Health Sciences, University of Wisconsin-Milwaukee, 2400 East Hartford Avenue, Milwaukee, WI, 53211, USA
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10
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Wuescher LM, Takashima A, Worth RG. A novel conditional platelet depletion mouse model reveals the importance of platelets in protection against Staphylococcus aureus bacteremia. J Thromb Haemost 2015; 13:303-13. [PMID: 25418277 PMCID: PMC4320667 DOI: 10.1111/jth.12795] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 11/16/2014] [Indexed: 12/29/2022]
Abstract
BACKGROUND Platelets are critical cells for maintaining vascular hemostasis, but their activities in other processes are becoming apparent. Specifically, the ability of platelets to recognize and respond to infectious agents is an important area of investigation. To understand the physiologic roles of platelets in vivo, most researchers have used antibody-mediated platelet depletion, which has certain limitations. OBJECTIVE To develop an optimal system with which to study the contribution of platelets to protection against S. aureus blood infection. METHODS Here, we describe a novel experimental model of conditional platelet depletion based on the Cre-recombinase cell ablation system. With this technology, the simian diphtheria toxin receptor was expressed in platelet factor 4-positive cells (megakaryocytes and platelets). RESULTS Systemic administration of diphtheria toxin every 48 h resulted in reduced platelet numbers that became undetectable after 6 days. Although platelets were depleted, no other blood cells were affected. With this newly developed model, the functional contributions of platelets to protection against Staphylococcus aureus bacteremia was examined. Platelet-depleted mice succumbed to infection more rapidly than wild-type mice, and had a significantly higher bacterial burden in kidneys, elevated levels of serum markers of kidney damage, and increased levels of cytokines indicative of septic shock. CONCLUSIONS Here, we illustrate a new mouse model for conditional platelet depletion, and implicate platelets as important participants in the immune response to bacterial blood infections.
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Affiliation(s)
- Leah M. Wuescher
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, 43614, USA
| | - Akira Takashima
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, 43614, USA
| | - Randall G. Worth
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, 43614, USA
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11
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Bumah VV, Masson-Meyers DS, Cashin S, Enwemeka CS. Optimization of the antimicrobial effect of blue light on methicillin-resistant Staphylococcus aureus (MRSA) in vitro. Lasers Surg Med 2015; 47:266-72. [PMID: 25639752 DOI: 10.1002/lsm.22327] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2014] [Indexed: 01/02/2023]
Abstract
BACKGROUND AND OBJECTIVE In previous studies, we showed that irradiation with 405 nm or 470 nm light suppresses up to 92% methicillin-resistant Staphylococcus aureus (MRSA) growth in vitro and that the remaining bacteria re-colonize. In this study, the aim was to develop a protocol that yields 100% MRSA growth suppression. MATERIALS AND METHODS We cultured 3 × 10(6) and 5 × 10(6) CFU/ml USA300 strain of MRSA and then irradiated each plate with varying fluences of 1-60 J/cm2 of 405 nm or 470 nm light, either once or twice at 6 hours intervals. Next, we plated 7 × 10(6) CFU/ml and irradiated it with 45, 50, 55, or 60 J/cm2 fluence, once, twice, or thrice at the same 6 hours intervals. In a third experiment, the same culture density was irradiated with 0, 165, 180, 220, or 240 J/cm(2) , either once, twice, or thrice. RESULTS Irradiation with either wavelength significantly reduced the bacterial colonies regardless of bacterial density (P < 0.05). At 3 × 10(6) CFU/ml density, nearly 40% and 50% growth of MRSA were suppressed with as little as 3 J/cm2 of 405 nm and 470 nm wavelengths, respectively. Moreover, 100% of the colonies were suppressed with a single exposure to 55 or 60 J/cm2 of 470 nm light or double treatment with 50, 55, or 60 J/cm2 of 405 nm wavelength. At 5 × 10(6) CFU/ml density, irradiating twice with 50, 55, or 60 J/cm2 of either wavelength suppressed bacterial growth completely, lower fluences did not. The denser 7 × 10(6) CFU/ml culture required higher doses to achieve 100% suppression, either one shot with 220 J/cm2 of 470 nm light or two shots of the same dose using 405 nm. CONCLUSION The bactericidal effect of blue light can be optimized to yield 100% bacterial growth suppression, but with relatively high fluences for dense bacterial cultures, such as 7 × 10(6) CFU/ml.
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Affiliation(s)
- Violet V Bumah
- College of Health Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53211
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12
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Jones MB, Montgomery CP, Boyle-Vavra S, Shatzkes K, Maybank R, Frank BC, Peterson SN, Daum RS. Genomic and transcriptomic differences in community acquired methicillin resistant Staphylococcus aureus USA300 and USA400 strains. BMC Genomics 2014; 15:1145. [PMID: 25527145 PMCID: PMC4630920 DOI: 10.1186/1471-2164-15-1145] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 12/08/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Staphylococcus aureus is a human pathogen responsible for substantial morbidity and mortality through its ability to cause a number of human infections including bacteremia, pneumonia and soft tissue infections. Of great concern is the emergence and dissemination of methicillin-resistant Staphylococcus aureus strains (MRSA) that are resistant to nearly all β-lactams. The emergence of the USA300 MRSA genetic background among community associated S. aureus infections (CA-MRSA) in the USA was followed by the disappearance of USA400 CA-MRSA isolates. RESULTS To gain a greater understanding of the potential fitness advantages and virulence capacity of S. aureus USA300 clones, we performed whole genome sequencing of 15 USA300 and 4 USA400 clinical isolates. A comparison of representative genomes of the USA300 and USA400 pulsotypes indicates a number of differences in mobile genome elements. We examined the in vitro gene expression profiles by microarray hybridization and the in vivo transcriptomes during lung infection in mice of a USA300 and a USA400 MRSA strain by performing complete genome qRT-PCR analysis. The unique presence and increased expression of 6 exotoxins in USA300 (12- to 600-fold) compared to USA400 may contribute to the increased virulence of USA300 clones. Importantly, we also observed the up-regulation of prophage genes in USA300 (compared with USA400) during mouse lung infection (including genes encoded by both prophages ΦSa2usa and ΦSa3usa), suggesting that these prophages may play an important role in vivo by contributing to the elevated virulence characteristic of the USA300 clone. CONCLUSIONS We observed differences in the genetic content of USA300 and USA400 strains, as well as significant differences of in vitro and in vivo gene expression of mobile elements in a lung pneumonia model. This is the first study to document the global transcription differences between USA300 and USA400 strains during both in vitro and in vivo growth.
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Affiliation(s)
- Marcus B Jones
- J. Craig Venter Institute, 4120 Capricorn Lane, La Jolla, CA, 92037, USA.
| | - Christopher P Montgomery
- Department of Pediatrics, Section of Critical Care, University of Chicago, Chicago, IL, 60637, USA.
| | - Susan Boyle-Vavra
- Department of Pediatrics, Section of Infectious Diseases, Chicago, IL, 60637, USA.
| | - Kenneth Shatzkes
- Department of Medicine, Center for Emerging and Re-emerging Pathogens, New Jersey Medical School, Rutgers Biomedical and Health Sciences, Rutgers University, Newark, NJ, 07103, USA.
| | - Rosslyn Maybank
- Battelle National Biodefense Institute, National Biodefense Analysis and Countermeasures Center, Frederick, MD, 21702, USA.
| | - Bryan C Frank
- J. Craig Venter Institute, 9704 Medical Center Drive, Rockville, MD, 20850, USA.
| | - Scott N Peterson
- Sanford Burnham Medical Research Institute, 10901 N. Torrey Pines Rd, La Jolla, CA, 92037, USA.
| | - Robert S Daum
- Department of Pediatrics, Section of Critical Care, University of Chicago, Chicago, IL, 60637, USA. .,Department of Pediatrics, Section of Infectious Diseases, Chicago, IL, 60637, USA.
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13
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Enwemeka CS. Antimicrobial blue light: an emerging alternative to antibiotics. Photomed Laser Surg 2013; 31:509-11. [PMID: 24138170 DOI: 10.1089/pho.2013.9871] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Affiliation(s)
- Chukuka S Enwemeka
- College of Health Sciences. University of Wisconsin-Milwaukee , Milwaukee, Wisconsin
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14
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Montagnani C, Cocchi P, Bianchi L, Resti M, de Martino M, Galli L. Severe infections caused by Panton-Valentine leukocidin-positive Staphylococcus aureus in infants: report of three cases and review of literature. Acta Paediatr 2013; 102:e284-7. [PMID: 23551699 DOI: 10.1111/apa.12225] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/25/2013] [Accepted: 02/28/2013] [Indexed: 12/11/2022]
Abstract
UNLABELLED We report three cases of severe infections in infants caused by Panton-Valentine leukocidin positive Staphylococcus aureus and evolved with a positive outcome. The literature of Panton-Valentine leukocidin positive Staphylococcus aureus infections in infants is reviewed. CONCLUSION Our findings suggest that a prompt identification of Panton-Valentine leukocidin positive Staphylococcus aureus and an appropriate therapy can reduce mortality and long-term sequelae. Further research is needed to specify features of Panton-Valentine leukocidin positive Staphylococcus aureus infections in infants.
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Affiliation(s)
- Carlotta Montagnani
- Department of Health Sciences; University of Florence; Anna Meyer Children's University Hospital; Florence Italy
| | - Priscilla Cocchi
- Department of Health Sciences; University of Florence; Anna Meyer Children's University Hospital; Florence Italy
| | - Leila Bianchi
- Department of Health Sciences; University of Florence; Anna Meyer Children's University Hospital; Florence Italy
| | - Massimo Resti
- Department of Health Sciences; University of Florence; Anna Meyer Children's University Hospital; Florence Italy
| | - Maurizio de Martino
- Department of Health Sciences; University of Florence; Anna Meyer Children's University Hospital; Florence Italy
| | - Luisa Galli
- Department of Health Sciences; University of Florence; Anna Meyer Children's University Hospital; Florence Italy
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15
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Bumah VV, Masson-Meyers DS, Cashin SE, Enwemeka CS. Wavelength and bacterial density influence the bactericidal effect of blue light on methicillin-resistant Staphylococcus aureus (MRSA). Photomed Laser Surg 2013; 31:547-53. [PMID: 23621894 DOI: 10.1089/pho.2012.3461] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE The purpose of this study was to investigate the effect of wavelength and methicillin-resistant Staphylococcus aureus (MRSA) density on the bactericidal effect of 405 and 470 nm light. BACKGROUND DATA It is recognized that 405 and 470 nm light-emitting diode (LED) light kill MRSA in standard 5 × 10(6) colony-forming units (CFU)/mL cultures; however, the effect of bacterial density on the bactericidal effect of each wavelength is not known. METHODS In three experiments, we cultured and plated US300 MRSA at four densities. Then, we irradiated each plate once with either wavelength at 0, 1, 3, 45, 50, 55, 60, and 220 J/cm(2). RESULTS Irradiation with either wavelength reduced bacterial colonies at each density (p<0.05). More bacteria were cleared as density increased; however, the proportion of colonies cleared, inversely decreased as density increased--the maximum being 100%, 96%, and 78% for 3 × 10(6), 5 × 10(6), and 7 × 10(6) CFU/mL cultures, respectively. Both wavelengths had similar effects on the sparser 3 × 10(6) and 5 × 10(6) CFU/mL cultures, but in the denser 7 × 10(6) CFU/mL culture, 405 nm light cleared more bacteria at each fluence (p<0.001). To determine the effect of beam penetration, denser 8 × 10(6) and 12 × 10(6) CFU/mL culture plates were irradiated either from the top, the bottom, or both directions. More colonies were eradicated from plates irradiated from top and bottom, than from plates irradiated from top or bottom at the same sum total fluences (p<0.001). CONCLUSIONS The bactericidal effect of LED blue light is limited more by light penetration of bacterial layers than by bacterial density per se.
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Affiliation(s)
- Violet V Bumah
- 1 College of Health Sciences, University of Wisconsin-Milwaukee , Milwaukee, Wisconsin
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16
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Long KL, Gilligan L, Cox KM, Draus JM. Characteristics of Children Referred for Drainage of Sub-cutaneous Soft Tissue Infections. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ijcm.2013.47a2006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Davis MF, Iverson SA, Baron P, Vasse A, Silbergeld EK, Lautenbach E, Morris DO. Household transmission of meticillin-resistant Staphylococcus aureus and other staphylococci. THE LANCET. INFECTIOUS DISEASES 2012; 12:703-16. [PMID: 22917102 DOI: 10.1016/s1473-3099(12)70156-1] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Although the role of pets in household transmission of meticillin-resistant Staphylococcus aureus (MRSA) has been examined previously, only minor attention has been given to the role of the abiotic household environment independent of, or in combination with, colonisation of pets and human beings to maintain transmission cycles of MRSA within the household. This report reviews published work about household transmission of S aureus and other staphylococci and describes contamination of household environmental surfaces and colonisation of pets and people. Household microbial communities might have a role in transfer of antimicrobial resistance genes and could be reservoirs for recolonisation of people, although additional research is needed regarding strategies for decontamination of household environments. Household-based interventions should be developed to control recurrent S aureus infections in the community, and coordination between medical and veterinary providers could be beneficial.
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Affiliation(s)
- Meghan F Davis
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
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