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Destrem AL, Maillard A, Simonet M, Simeon S, Contejean A, Vignau C, Pires L, Isnard M, Vitrat V, Delory T, Maillet M. Effectiveness and safety of cefazolin versus cloxacillin in endocarditis due to methicillin-susceptible Staphylococcus spp.: a multicenter propensity weighted cohort study. Eur J Clin Microbiol Infect Dis 2024; 43:1569-1577. [PMID: 38806841 DOI: 10.1007/s10096-024-04851-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 05/09/2024] [Indexed: 05/30/2024]
Abstract
PURPOSE To compare the effectiveness and safety of cefazolin versus cloxacillin for the treatment of infective endocarditis (IE) due to methicillin-sensitive Staphylococci (MSS). METHODS Data were retrospectively collected on patients treated for a definite MSS endocarditis who received cefazolin or cloxacillin for at least 10 consecutive days in six French hospitals between January-1 2014 and December-31 2020. The primary endpoint was treatment failure defined as a composite of death within 90 days of starting antibiotherapy, or embolic event during antibiotherapy, or relapse of IE within 90 days of stopping antibiotherapy. We used Cox regression adjusted for the inverse probability of treatment weighting of receiving cefazolin. RESULTS 192 patients were included (median age 67.8 years). IE was caused by S.aureus in 175 (91.1%) and by coagulase-negative staphylococci in 17 (8.9%). Ninety-four patients (48.9%) received cefazolin, and 98 (51%) received cloxacillin. 34 patients (34.7%) with cefazolin and 26 (27.7%) with cloxacillin met the composite primary endpoint, with no significant differences between groups (adjusted HR = 1.13, 95% CI 0.63 to 2.03). There were no significant differences in secondary efficacy endpoints or biological safety events. CONCLUSION The effectiveness of cefazolin did not significantly differ from cloxacillin for the treatment of MSS endocarditis.
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Affiliation(s)
- Anne-Laure Destrem
- Infectious Diseases Department, Centre Hospitalier Métropole Savoie, Chambéry, France
| | - Alexis Maillard
- Infectious Diseases Department, Pitié-Salpêtrière University Hospital, Paris, France
| | - Mathieu Simonet
- Infectious Diseases Department, Centre Hospitalier Annecy Genevois, Annecy, France
| | - Soline Simeon
- Infectious Diseases Department, Henri Mondor University Hospital, Paris, France
| | - Adrien Contejean
- Infectious Diseases Department, Cochin University Hospital, Paris, France
- Hematology Department, Centre Hospitalier Annecy Genevois, Annecy, France
| | - Clémentin Vignau
- Infectious Diseases Department, Grenoble University Hospital, Grenoble, France
| | - Lucas Pires
- Clinical Research Unit, Centre Hospitalier Annecy Genevois, Annecy, France
| | - Margaux Isnard
- Infectious Diseases Department, Centre Hospitalier Métropole Savoie, Chambéry, France
| | - Virginie Vitrat
- Infectious Diseases Department, Centre Hospitalier Annecy Genevois, Annecy, France
| | - Tristan Delory
- Clinical Research Unit, Centre Hospitalier Annecy Genevois, Annecy, France
| | - Mylène Maillet
- Infectious Diseases Department, Centre Hospitalier Annecy Genevois, Annecy, France.
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Carvajal LP, Rincon S, Gomez-Villegas SI, Matiz-González JM, Ordoñez K, Santamaria A, Ospina-Navarro L, Beltran J, Guevara F, Mendez YR, Salcedo S, Porras A, Valencia-Moreno A, Grennia H, Deyanov A, Baptista R, Tam VH, Panesso D, Tran TT, Miller WR, Arias CA, Reyes J. Prevalence of the Cefazolin Inoculum Effect (CzIE) in Nasal Colonizing Methicillin-Susceptible Staphylococcus aureus in Patients from Intensive Care Units in Colombia and Use of a Modified Rapid Nitrocefin Test for Detection. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.07.11.24309236. [PMID: 39040169 PMCID: PMC11261917 DOI: 10.1101/2024.07.11.24309236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
The cefazolin inoculum effect (CzIE) has been associated with poor clinical outcomes in patients with MSSA infections. We aimed to investigate the point prevalence of the CzIE among nasal colonizing MSSA isolates from ICU patients in a multicenter study in Colombia (2019-2023). Patients underwent nasal swabs to assess for S. aureus colonization on admission to the ICU and some individuals had follow-up swabs. We performed cefazolin MIC by broth-microdilution using standard and high-inoculum and developed a modified nitrocefin-based rapid test to detect the CzIE. Whole genome sequencing was carried out to characterize BlaZ types and allotypes, phylogenomics and Agr-typing. All swabs were subjected to 16S-rRNA metabarcoding sequencing to evaluate microbiome characteristics associated with the CzIE. A total of 352 patients were included; 46/352 (13%) patients were colonized with S. aureus; 22% (10/46) and 78% (36/46) with MRSA and MSSA, respectively. Among 36 patients that contributed with 43 MSSA colonizing isolates, 21/36 (58%) had MSSA exhibiting the CzIE. BlaZ type A and BlaZ-2 were the predominant type and allotype in 56% and 52%, respectively. MSSA belonging to CC30 were highly associated with the CzIE and SNP analyses supported transmission of MSSA exhibiting the CzIE among some patients of the same unit. The modified nitrocefin rapid test had 100%, 94.4% and 97.7% sensitivity, specificity and accuracy, respectively. We found a high prevalence point prevalence of the CzIE in MSSA colonizing the nares of critically-ill patients in Colombia. A modified rapid test was highly accurate in detecting the CzIE in this patient population.
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Affiliation(s)
- Lina P. Carvajal
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogota, Colombia
| | - Sandra Rincon
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogota, Colombia
| | | | - Juan M. Matiz-González
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogota, Colombia
| | - Karen Ordoñez
- Department of Infectious Diseases, ESE Hospital Universitario, San Jorge de Pereira, Pereira, Colombia
| | - Alejandra Santamaria
- Department of Infectious Diseases, ESE Hospital Universitario, San Jorge de Pereira, Pereira, Colombia
| | | | | | - Fredy Guevara
- Servicio de Infectología, Fundación Santafe de Bogota, Bogota, Colombia
- Clinica Reina Sofia, Colsanitas, Bogota, Colombia
| | - Yardany R. Mendez
- Grupo de Investigacion en Epidemiologia Clinica de Colombia (GRECO), Universidad Pedagogica y Tecnologica de Colombia, Tunja, Colombia
- Hospital Regional de Duitama, Duitama, Colombia
| | - Soraya Salcedo
- Organizacion Clinica General del Norte, Barranquilla, Colombia
| | | | | | - Haley Grennia
- Center for Infectious Disease, Houston Methodist Research Institute, Houston, TX USA
| | - Alexander Deyanov
- Center for Infectious Disease, Houston Methodist Research Institute, Houston, TX USA
| | - Rodrigo Baptista
- Center for Infectious Disease, Houston Methodist Research Institute, Houston, TX USA
- Division of Infectious Diseases and Department of Medicine, Houston Methodist Hospital, Houston, TX USA 77030
- Department of Medicine, Weill Cornell Medical College, New York, NY
| | - Vincent H. Tam
- Departament of Pharmacy Practice and Translational Research, University of Houston, Houston, Texas, United States
| | - Diana Panesso
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogota, Colombia
- Center for Infectious Disease, Houston Methodist Research Institute, Houston, TX USA
- Division of Infectious Diseases and Department of Medicine, Houston Methodist Hospital, Houston, TX USA 77030
- Department of Medicine, Weill Cornell Medical College, New York, NY
| | - Truc T. Tran
- Center for Infectious Disease, Houston Methodist Research Institute, Houston, TX USA
- Division of Infectious Diseases and Department of Medicine, Houston Methodist Hospital, Houston, TX USA 77030
- Department of Medicine, Weill Cornell Medical College, New York, NY
| | - William R. Miller
- Center for Infectious Disease, Houston Methodist Research Institute, Houston, TX USA
- Division of Infectious Diseases and Department of Medicine, Houston Methodist Hospital, Houston, TX USA 77030
- Department of Medicine, Weill Cornell Medical College, New York, NY
| | - Cesar A. Arias
- Center for Infectious Disease, Houston Methodist Research Institute, Houston, TX USA
- Division of Infectious Diseases and Department of Medicine, Houston Methodist Hospital, Houston, TX USA 77030
- Department of Medicine, Weill Cornell Medical College, New York, NY
| | - Jinnethe Reyes
- Molecular Genetics and Antimicrobial Resistance Unit, Universidad El Bosque, Bogota, Colombia
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3
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Lo CKF, Sritharan A, Zhang J, Li N, Zhang C, Wang F, Loeb M, Bai AD. Clinical significance of cefazolin inoculum effect in serious MSSA infections: a systematic review. JAC Antimicrob Resist 2024; 6:dlae069. [PMID: 38716403 PMCID: PMC11073751 DOI: 10.1093/jacamr/dlae069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 04/10/2024] [Indexed: 06/29/2024] Open
Abstract
Background The cefazolin inoculum effect (CzIE) is a phenomenon whereby some MSSA isolates demonstrate resistance to cefazolin when a high bacterial inoculum is used for susceptibility testing. The clinical significance of this phenotypic phenomenon remains unclear. We conducted a systematic review to answer the following question: In patients with serious MSSA infection treated with cefazolin, does infection due to CzIE-positive MSSA isolates result in worse clinical outcomes than infection due to CzIE-negative MSSA isolates? Methods Ovid MEDLINE, Embase, Cochrane CENTRAL, medRxiv and bioRxiv were searched from inception until 12 April 2023. Studies were included if they tested for CzIE in clinical isolates from MSSA infections in humans. Two independent reviewers extracted data and conducted risk-of-bias assessment. Main outcomes were treatment failure and mortality. Pooling of study estimates was not performed given the heterogeneity of patient populations and outcome definitions. Results Twenty-three observational studies were included. CzIE presence amidst MSSA isolates ranged from 0% to 55%. There was no statistically significant mortality difference in two studies that compared MSSA infections with and without CzIE, with ORs ranging from 0.72 to 19.78. Of four studies comparing treatment failure, ORs ranged from 0.26 to 13.00. One study showed a significantly higher treatment failure for the CzIE group, but it did not adjust for potential confounders. Conclusions The evidence on CzIE is limited by small observational studies. In these studies, CzIE did not predict higher mortality in MSSA infections treated with cefazolin. Our findings do not support CzIE testing in clinical practice currently.
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Affiliation(s)
- Calvin Ka-Fung Lo
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Ashwin Sritharan
- Michael G. DeGroote Undergraduate School of Medicine, McMaster University, Hamilton, ON, Canada
| | - Jiesi Zhang
- Faculty of Health Sciences, Queen’s University, Kingston, ON, Canada
| | - Nicole Li
- Faculty of Arts and Sciences, Queen's University, Kingston, ON, Canada
| | - Cindy Zhang
- Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
| | - Frank Wang
- Michael G. DeGroote Undergraduate School of Medicine, McMaster University, Hamilton, ON, Canada
| | - Mark Loeb
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada
| | - Anthony D Bai
- Division of Infectious Diseases, Department of Medicine, Queen’s University, Kingston, ON, Canada
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Ghany SSHAE, Ibrahem RA, El-Gendy AO, El-Baky RMA, Mustafa A, Azmy AF. Novel synergistic interactions between monolaurin, a mono-acyl glycerol and β lactam antibiotics against Staphylococcus aureus: an in vitro study. BMC Infect Dis 2024; 24:379. [PMID: 38584271 PMCID: PMC11000382 DOI: 10.1186/s12879-024-09261-9] [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: 09/05/2023] [Accepted: 03/26/2024] [Indexed: 04/09/2024] Open
Abstract
BACKGROUND A major worldwide health issue is the rising frequency of resistance of bacteria.Drug combinations are a winning strategy in fighting resistant bacteria and might help in protecting the existing drugs.Monolaurin is natural compound extracted from coconut oil and has a promising antimicrobial activity against Staphylococcus.aureus. This study aims to examine the efficacy of monolaurin both individually and in combination with β-lactam antibiotics against Staphylococcus aureus isolates. METHODS Agar dilution method was used for determination of minimum inhibitory concentration (MIC) of monolaurin against S.aureus isolates. Scanning electron microscope (SEM) was used to detect morphological changes in S.aureus after treatment with monolaurin. Conventional and Real-time Polymerase chain reaction (RT-PCR) were performed to detect of beta-lactamase (blaZ) gene and its expressional levels after monolaurin treatment. Combination therapy of monolaurin and antibiotics was assessed through fractional inhibitory concentration and time-kill method. RESULTS The antibacterial activity of monolaurin was assessed on 115 S.aureus isolates, the MIC of monolaurin were 250 to 2000 µg/ml. SEM showed cell elongation and swelling in the outer membrane of S.aureus in the prescence of 1xMIC of monolaurin. blaZ gene was found in 73.9% of S.aureus isolates. RT-PCR shows a significant decrease in of blaZ gene expression at 250 and 500 µg/ml of monolaurin. Synergistic effects were detected through FIC method and time killing curve. Combination therapy established a significant reduction on the MIC value. The collective findings from the antibiotic combinations with monolaurin indicated synergism rates ranging from 83.3% to 100%.In time-kill studies, combination of monolaurin and β-lactam antibiotics produced a synergistic effect. CONCLUSION This study showed that monolaurin may be a natural antibacterial agent against S. aureus, and may be an outstanding modulator of β-lactam drugs. The concurrent application of monolaurin and β-lactam antibiotics, exhibiting synergistic effects against S. aureus in vitro, holds promise as potential candidates for the development of combination therapies that target particularly, patients with bacterial infections that are nearly incurable.
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Affiliation(s)
- Shimaa Salah Hassan Abd El Ghany
- Department of Microbiology and Immunology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, 62514, Egypt
- Department of Microbiology and Immunology, Faculty of Pharmacy, Deraya University, Minia, 11566, Egypt
| | - Reham A Ibrahem
- Department of Microbiology and Immunology, Faculty of Pharmacy, Minia University, Minia, 61519, Egypt.
| | - Ahmed Osama El-Gendy
- Department of Microbiology and Immunology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, 62514, Egypt
| | - Rehab Mahmoud Abd El-Baky
- Department of Microbiology and Immunology, Faculty of Pharmacy, Deraya University, Minia, 11566, Egypt
- Department of Microbiology and Immunology, Faculty of Pharmacy, Minia University, Minia, 61519, Egypt
| | - Ahmad Mustafa
- Faculty of Engineering, October University for Modern Science and Arts (MSA), Giza, Egypt
| | - Ahmed Farag Azmy
- Department of Microbiology and Immunology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, 62514, Egypt
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Svishchuk J, Ebbert K, Waddell B, Izydorczyk C, Acosta N, Somayaji R, Rabin HR, Bjornson CL, Lisboa L, Gregson DB, Conly JM, Surette MG, Parkins MD. Epidemiology and impact of methicillin-sensitive Staphylococcus aureus with β-lactam antibiotic inoculum effects in adults with cystic fibrosis. Antimicrob Agents Chemother 2023; 67:e0013623. [PMID: 37966229 PMCID: PMC10720481 DOI: 10.1128/aac.00136-23] [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: 01/31/2023] [Accepted: 08/22/2023] [Indexed: 11/16/2023] Open
Abstract
Staphylococcus aureus is the most prevalent cystic fibrosis (CF) pathogen. Several phenotypes are associated with worsened CF clinical outcomes including methicillin-resistance and small-colony-variants. The inoculum effect (IE) is characterized by reduced β-lactam susceptibility when assessed at high inoculum. The IE associates with worse outcomes in bacteremia and other high-density infections, and may therefore be relevant to CF. The prevalence of IE amongst a CF cohort (age ≥18 years), followed from 2013 to 2016, was investigated. Yearly methicillin-sensitive S. aureus (MSSA) isolates were screened at standard (5 × 105 CFU/mL) and high (5 × 107 CFU/mL) inoculum against narrow-spectrum anti-Staphylococcal β-lactams and those with anti-pseudomonal activity common to CF. A ≥ 4-fold increase in minimum inhibitory concentration between standard and high inoculum defined IE. Isolates underwent blaZ sequencing and genotyping and were compared against published genomes. Fifty-six percent (99/177) of individuals had MSSA infection. MSSA was observed at ≥105 CFU/mL in 44.8% of entry sputum samples. The prevalence of the IE was 25.0%-cefazolin; 13.5%-cloxacillin; 0%-meropenem; 1.0%-cefepime; 5.2%-ceftazidime; and 34.4%-piperacillin-tazobactam amongst baseline MSSA isolates assessed. blaZ A associated with cefazolin IE (P = 0.0011), whereas blaZ C associated with piperacillin-tazobactam IE (P < 0.0001). Baseline demographics did not reveal specific risk factors for IE-associated infections, nor were long-term outcomes different. Herein, we observed the IE in CF-derived MSSA disproportionally for cefazolin and piperacillin-tazobactam and this phenotype strongly associated with underlying blaZ genotype. The confirmation of CF being a high density infection, and the identification of high prevalence of MSSA with IE in CF supports the need for prospective pulmonary exacerbation treatment studies to understand the impact of this phenotype.
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Affiliation(s)
- J. Svishchuk
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - K. Ebbert
- Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada
| | - B. Waddell
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - C. Izydorczyk
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - N. Acosta
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - R. Somayaji
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
- Department of Medicine, University of Calgary and Alberta Health Services, Calgary, Alberta, Canada
| | - H. R. Rabin
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
| | - C. L. Bjornson
- Department of Pediatrics, University of Calgary, Calgary, Alberta, Canada
| | - L. Lisboa
- Department of Pathology and Laboratory Medicine, University of Calgary and Alberta Health Services, Calgary, Alberta, Canada
| | - D. B. Gregson
- Department of Medicine, University of Calgary and Alberta Health Services, Calgary, Alberta, Canada
- Department of Pathology and Laboratory Medicine, University of Calgary and Alberta Health Services, Calgary, Alberta, Canada
| | - J. M. Conly
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
- Department of Medicine, University of Calgary and Alberta Health Services, Calgary, Alberta, Canada
- Department of Pathology and Laboratory Medicine, University of Calgary and Alberta Health Services, Calgary, Alberta, Canada
| | - M. G. Surette
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - M. D. Parkins
- Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary, Alberta, Canada
- Department of Medicine, University of Calgary and Alberta Health Services, Calgary, Alberta, Canada
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6
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Chastain DB, Covert KL, Tu PJ, McDougal S, White BP, Cluck D. Therapeutic Options for Adult Patients With Persistent Methicillin-Susceptible Staphylococcus aureus Bacteremia: A Narrative Review. Ann Pharmacother 2023; 57:1312-1327. [PMID: 36946576 DOI: 10.1177/10600280231158809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023] Open
Abstract
OBJECTIVE To compare the efficacy of antimicrobial therapies used in the management of persistent methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia. DATA SOURCES A literature search using the PubMed database (inception to December 2022) was conducted using the search terms "Staphylococcus aureus bacteremia," "methicillin-susceptible Staphylococcus aureus bacteremia," "persistent methicillin-susceptible Staphylococcus aureus bacteremia," and "refractory methicillin-susceptible Staphylococcus aureus bacteremia ." In addition, therapeutic agents which could be used as treatment for MSSA including "nafcillin," "oxacillin," "cefazolin," "ceftaroline," "gentamicin," "rifampin," and "daptomycin" were also combined with the aforementioned search terms to capture data using these agents. STUDY SELECTION/DATA EXTRACTION Clinical data were limited to those published in the English language. Articles and abstracts were considered for inclusion in addition to ongoing trials identified through ClinicalTrials.gov. DATA SYNTHESIS A total of 78 articles were reviewed including 17 in vitro or animal model studies and 39 studies including patient data. The remaining 22 articles included guidelines, review articles, and editorials. Recent data evaluating use of dual β-lactam regimens for persistent MSSA bacteremia were limited to 8 case reports or case series. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE At present, there is little guidance on how to best manage patients with persistent MSSA bacteremia. This narrative review collates the available data to assist clinicians in selecting the best possible antimicrobial regimen when facing this clinical conundrum. CONCLUSIONS Modification of antimicrobial therapy, in conjunction with source control and infectious diseases consultation, may all be necessary to sterilize blood cultures in patients with persistent MSSA bacteremia.
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Affiliation(s)
- Daniel B Chastain
- Department of Clinical & Administrative Pharmacy, University of Georgia College of Pharmacy, Albany, GA, USA
| | - Kelly L Covert
- Department of Pharmacy Practice, Bill Gatton College of Pharmacy, East Tennessee State University, Johnson City, TN, USA
| | - Patrick J Tu
- Charlie Norwood VA Medical Center, Augusta, GA, USA
| | - Steven McDougal
- Department of Pharmacy Services, University of Utah Hospital, Salt Lake City, UT, USA
| | | | - David Cluck
- Department of Pharmacy Practice, Bill Gatton College of Pharmacy, East Tennessee State University, Johnson City, TN, USA
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7
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Bourreau A, Le Mabecque V, Broquet A, Caillon J. Prevalence of a cefazolin inoculum effect associated with blaZ gene types, and clinical outcomes among methicillin-susceptible Staphylococcus aureus blood isolates of patients with infective endocarditis. Infect Dis Now 2023; 53:104626. [PMID: 36184048 DOI: 10.1016/j.idnow.2022.09.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 04/21/2022] [Accepted: 09/23/2022] [Indexed: 11/28/2022]
Abstract
OBJECTIVES A proportion of blaZ gene-positive methicillin-susceptible Staphylococcus aureus (MSSA) strains exhibits the cefazolin inoculum effect (CInE). Its clinical impact remains uncertain but could compromise the use of cefazolin in high-burden infections. To date, no study has been conducted in France or in Europe. We aimed to assess the prevalence of CInE and its association with blaZ beta-lactamase and S. aureus protein A (spa) types, and to assess the clinical outcomes in cefazolin-treated patients for infective endocarditis whose strain exhibited a CInE. METHODS This was a French single-center retrospective study of 51 MSSA strains from patients of the Nantes endocarditis prospective cohort, conducted between 2013 and 2018. RESULTS Cefazolin MIC50 at high inoculum was 2 mg/L (IQR 1-2). CInE was found in 17.6 % of tested strains. Among blaZ-positive strains (n = 44), type A beta-lactamase was predominant (n = 25, 57 %). Thirty-seven S. aureus protein A (spa) types were found. No statistical association was shown between blaZ or spa types and CInE. CInE was neither associated with a higher rate of persistent bacteremia (25 % vs 56.3 %, p = 0.58) nor with clinical failure in patients treated with cefazolin, in comparison to patients with no CInE strain (25 % vs 56.3 %, p = 0.58). CONCLUSION The cefazolin inoculum effect was found in a substantial number of Staphylococcus aureus strains; however, minimum inhibitory concentrations remained globally low. CInE was not associated with a higher proportion of clinical failure on treatment.
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Affiliation(s)
- A Bourreau
- Department of Infectious Diseases, Nantes, France; Centre d'Investigation Clinique, Unité d'Investigation Clinique 1413 INSERM, CHU Nantes, Nantes, France.
| | - V Le Mabecque
- Institut de RechercheenSanté de l'Université de Nantes, EA 3826-Thérapeutiques cliniques et expérimentales des infections, France
| | - A Broquet
- Institut de RechercheenSanté de l'Université de Nantes, EA 3826-Thérapeutiques cliniques et expérimentales des infections, France
| | - J Caillon
- Department of Bacteriology, CHU Hôtel-Dieu, Nantes, France
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8
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Tuon FF, Suss PH, Telles JP, Dantas LR, Borges NH, Ribeiro VST. Antimicrobial Treatment of Staphylococcus aureus Biofilms. Antibiotics (Basel) 2023; 12:antibiotics12010087. [PMID: 36671287 PMCID: PMC9854895 DOI: 10.3390/antibiotics12010087] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/01/2023] [Accepted: 01/03/2023] [Indexed: 01/06/2023] Open
Abstract
Staphylococcus aureus is a microorganism frequently associated with implant-related infections, owing to its ability to produce biofilms. These infections are difficult to treat because antimicrobials must cross the biofilm to effectively inhibit bacterial growth. Although some antibiotics can penetrate the biofilm and reduce the bacterial load, it is important to understand that the results of routine sensitivity tests are not always valid for interpreting the activity of different drugs. In this review, a broad discussion on the genes involved in biofilm formation, quorum sensing, and antimicrobial activity in monotherapy and combination therapy is presented that should benefit researchers engaged in optimizing the treatment of infections associated with S. aureus biofilms.
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Affiliation(s)
- Felipe Francisco Tuon
- Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba 80215-901, Paraná, Brazil
- Correspondence: ; Tel.: +55-41-98852-1893
| | - Paula Hansen Suss
- Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba 80215-901, Paraná, Brazil
| | - Joao Paulo Telles
- AC Camargo Cancer Center, Infectious Diseases Department, São Paulo 01525-001, São Paulo, Brazil
| | - Leticia Ramos Dantas
- Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba 80215-901, Paraná, Brazil
| | - Nícolas Henrique Borges
- Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba 80215-901, Paraná, Brazil
| | - Victoria Stadler Tasca Ribeiro
- Laboratory of Emerging Infectious Diseases, School of Medicine, Pontifícia Universidade Católica do Paraná, Curitiba 80215-901, Paraná, Brazil
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9
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Antosz K, Battle S, Chang J, Scheetz MH, Al-Hasan M, Bookstaver PB. Cefazolin in the treatment of central nervous system infections: A narrative review and recommendation. Pharmacotherapy 2023; 43:85-95. [PMID: 36521869 DOI: 10.1002/phar.2750] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 12/23/2022]
Abstract
Infections of the central nervous system (CNS) are complex to treat and associated with significant morbidity and mortality. Historically, antistaphylococcal penicillins such as nafcillin were recommended for the treatment of methicillin-susceptible staphylococcal CNS infections. However, the use of antistaphylococcal penicillins presents challenges, such as frequent dosing administration and adverse events with protracted use. This narrative reviews available clinical and pharmacokinetic/pharmacodynamic (PK/PD) data for cefazolin in CNS infections and produces a recommendation for use. Based on the limited available evidence analyzed, dose optimized cefazolin is likely a safe and effective alternative to antistaphylococcal penicillins for a variety of CNS infections due to methicillin-susceptible Staphylococcus aureus. Given the site of infection and wide therapeutic index of cefazolin, practitioners may consider dosing cefazolin regimens of 2 g IV every 6 h or a continuous infusion of 8-10 g daily instead of 2 g IV every 8 h to optimize PK/PD properties.
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Affiliation(s)
- Kayla Antosz
- Department of Clinical Pharmacy and Outcomes Sciences, University of South Carolina College of Pharmacy, Columbia, South Carolina, USA
- Prisma Health-Midlands, Columbia, South Carolina, USA
| | - Sarah Battle
- Prisma Health-Midlands, Columbia, South Carolina, USA
- Department of Medicine, Division of Infectious Diseases, University of South Carolina School of Medicine, Columbia, South Carolina, USA
| | - Jack Chang
- Pharmacometrics Center of Excellence, Department of Pharmacy Practice, Midwestern University College of Pharmacy, Downers Grove, Illinois, USA
- Department of Pharmacy, Northwestern Memorial Hospital, Chicago, Illinois, USA
| | - Marc H Scheetz
- Pharmacometrics Center of Excellence, Department of Pharmacy Practice, Midwestern University College of Pharmacy, Downers Grove, Illinois, USA
- Department of Pharmacy, Northwestern Memorial Hospital, Chicago, Illinois, USA
| | - Majdi Al-Hasan
- Prisma Health-Midlands, Columbia, South Carolina, USA
- Department of Medicine, Division of Infectious Diseases, University of South Carolina School of Medicine, Columbia, South Carolina, USA
| | - P Brandon Bookstaver
- Department of Clinical Pharmacy and Outcomes Sciences, University of South Carolina College of Pharmacy, Columbia, South Carolina, USA
- Prisma Health-Midlands, Columbia, South Carolina, USA
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10
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Prevalence and Characterization of the Cefazolin Inoculum Effect in North American Methicillin-Susceptible Staphylococcus aureus Isolates. J Clin Microbiol 2022; 60:e0249521. [PMID: 35578988 PMCID: PMC9297818 DOI: 10.1128/jcm.02495-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Antistaphylococcal penicillins and cefazolin remain the primary treatments for infections with methicillin-susceptible Staphylococcus aureus (MSSA). The cefazolin inoculum effect (CzIE) causes the cefazolin MIC to be elevated in proportion to the number of bacteria in the inoculum. The objective of this multicenter study was to evaluate the prevalence of the CzIE in North American MSSA isolates. Clinical MSSA isolates from six microbiology laboratories in the United States and one microbiology laboratory in Canada were screened for the CzIE by broth microdilution at a standard inoculum (~5 × 105 CFU/mL) and a high inoculum (~5 × 107 CFU/mL). Genome sequencing was performed to further characterize the MSSA isolates. The CzIE was present in 57/305 (18.6%) MSSA isolates, ranging from 0% to 27.9% across study sites. More of the CzIE-positive isolates (29.8%) had standard inoculum cefazolin MICs of 1.0 μg/mL than the CzIE-negative isolates did (3.2%) (P < 0.0001). Conversely, more CzIE-negative isolates (39.5%) had standard inoculum MICs of 0.25 μg/mL than the CzIE positive isolates did (5.3%) (P < 0.0001). The most common BlaZ β-lactamase types found in the CzIE-positive strains were type C (53.7%) and type A (44.4%). ST8 and ST30 were the most common sequence types among CzIE-positive isolates and correlated with BlaZ type C and A, respectively. The CzIE was present in up to a quarter of clinical MSSA isolates from North American clinical laboratories. Further studies to determine the impact of the presence of the CzIE on clinical outcomes are needed.
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11
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Bloomer AK, Coe KM, Brandt AM, Roomian T, Brighton B, Scannell BP. Hold the Antibiotics: Are Preoperative Antibiotics Unnecessary in the Treatment of Pediatric Supracondylar Humerus Fractures? J Pediatr Orthop 2022; 42:e474-e479. [PMID: 35200212 DOI: 10.1097/bpo.0000000000002118] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Supracondylar humerus (SCH) fracture is the most common elbow injury in children and often treated with closed reduction and percutaneous pinning (CRPP). There is little published evidence supporting or refuting the use of perioperative prophylactic antibiotics for SCH CRPP in the pediatric population. The purpose of this study is to evaluate the rate of surgical site infection for patients with and without preoperative antibiotics. METHODS A retrospective chart review was conducted of patients less than or equal to 16 years from 2012 to 2018 who underwent primary CRPP. Open fractures, multilimbed polytraumas, and immunodeficient patients were excluded. Infection rates were compared using a noninferiority test assuming a 3% infection rate and a predefined noninferiority margin of 4%. A total of 255 patients were needed to adequately power the study. RESULTS Of the 1253 cases identified, 845 met eligibility criteria. A total of 337 received antibiotics, and 508 did not. Preoperative nerve injury (P=0.0244) and sterilization technique (P<0.0001) were associated with antibiotic use: 4 patients developed an infection; there were successfully treated superficial infections, and 1 was a deep infection requiring a formal debridement. There were 8 patients that had a recorded mal-union, and 6 patients required additional procedures; 1 patient had a postoperative compartment syndrome on postoperation day 1. The infection rates among patients treated with and without antibiotics were 0.60% and 0.40%, respectively. The absence of antibiotics was not clinically inferior to using antibiotics (P=0.003). CONCLUSIONS Infection remains a rare complication following CRPP of SCH fractures. According to our current data, not giving perioperative antibiotics was not inferior to using perioperative antibiotics for preventing superficial or deep infection in patients undergoing CRPP of SCH fractures. With the increase in attention to antibiotic stewardship, it is important to eliminate unnecessary antibiotic use while continuing to maintain a low rate of surgical site infection. LEVEL OF EVIDENCE Level IV-case series. This is a therapeutic study that investigates the results from a case series.
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Affiliation(s)
- Ainsley K Bloomer
- Department of Orthopaedic Surgery, Atrium Health Musculoskeletal Institute
| | - Kelsie M Coe
- Department of Orthopaedic Surgery, Atrium Health Musculoskeletal Institute
| | - Aaron M Brandt
- Department of Orthopaedic Surgery, Atrium Health Musculoskeletal Institute
| | - Tamar Roomian
- Department of Orthopaedic Surgery, Atrium Health Musculoskeletal Institute
| | - Brian Brighton
- Department of Orthopaedic Surgery, Atrium Health Musculoskeletal Institute
- OrthoCarolina, Charlotte, NC
| | - Brian P Scannell
- Department of Orthopaedic Surgery, Atrium Health Musculoskeletal Institute
- OrthoCarolina, Charlotte, NC
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12
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Staphylococcus aureus in Non-Cystic Fibrosis Bronchiectasis: Prevalence and Genomic Basis of High Inoculum Beta-Lactam Resistance. Ann Am Thorac Soc 2022; 19:1285-1293. [PMID: 35213810 DOI: 10.1513/annalsats.202108-965oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rationale The pathobiology of Staphylococcus aureus in non-cystic fibrosis bronchiectasis (nCFB) is poorly defined. When present at high density or "inoculum", some methicillin-sensitive S. aureus (MSSA) can inefficiently degrade anti-Staphylococcal beta-lactam antibiotics via BlaZ penicillinases (termed, the inoculum effect). Given the high burden of organisms in bronchiectatic airways, this is particularly relevant. Objectives Drawing from a prospectively-collected biobank, we sought to understand the prevalence, natural history, potential for transmission, and antibiotic resistance profiles amongst nCFB-derived MSSA isolates. Methods All individuals attending a regional consultancy nCFB clinic with sputum collected between 1981-2017 were considered, and those with ≥1 S. aureus-positive culture comprised the cohort. Each individual's most recent biobank isolate was subjected to whole genome sequencing (including the blaZ gene), antibacterial susceptibility testing, and comparative beta-lactam testing at standard (5 x 105CFU/mL) and high (5 x 107CFU/mL) inoculum to assess for the inoculum, and pronounced inoculum effect (IE and pIE, respectively). Results Seventy-four of 209 (35.4%) individuals had ≥1 sputum sample(s) with S. aureus (68 MSSA, 6 MRSA). Those with S. aureus infection were more likely to be female. Amongst 60/74 MSSA isolates subjected to WGS, no evidence of transmission was identified, although specific MLST types were prevalent including ST-1, ST-15, ST-30, and ST-45. Antibiotic resistance was uncommon except for macrolides (~20%). Amongst the 60 MSSA, prevalence of IE and pIE, respectively, were observed to be drug specific; meropenem (0%, 0%), cefepime (3%, 5%), ceftazidime (8%, 0%), cloxacillin (12%, 0%), cefazolin (23%, 0%) and piperacillin-tazobactam (37%, 17%). The cefazolin IE associated with blaZ type A (p<0.01) and ST-30 (p<0.01), whereas the piperacillin-tazobactam IE associated with type C blaZ (p<0.001) and ST-15 (p<0.05). Conclusions S. aureus infection was common, although no evidence of transmission was apparent in our nCFB cohort. While routine susceptibility testing did not identify significant resistance, inoculum-related resistance was found to be relevant for commonly used nCFB antibiotics including cefazolin and piperacillin-tazobactam. Given previous associations between IEs and negative patient outcomes, further work is warranted to understand how this phenotype impacts nCFB disease progression.
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13
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Yetmar ZA, Razi S, Nayfeh T, Gerberi DJ, Mahmood M, Abu Saleh OM. Ceftriaxone versus antistaphylococcal antibiotics for definitive treatment of methicillin-susceptible Staphylococcus aureus infections: a systematic review and meta-analysis. Int J Antimicrob Agents 2021; 59:106486. [PMID: 34839007 DOI: 10.1016/j.ijantimicag.2021.106486] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 11/10/2021] [Accepted: 11/19/2021] [Indexed: 12/26/2022]
Abstract
Optimal therapy for methicillin-susceptible Staphylococcus aureus (MSSA) infections is unclear. Current standard of care consists of antistaphylococcal antibiotics (ASAs) such as nafcillin, oxacillin and cefazolin. Ceftriaxone has been evaluated due to its advantage as a once-daily outpatient regimen. However, questions remain regarding its efficacy compared with ASAs. We aimed to conduct a review and synthesis of available literature for outcomes of patients treated with ceftriaxone or ASAs for MSSA infections. We searched Cochrane Central Register of Controlled Trials, Embase Ovid, MEDLINE Ovid, Scopus and Web of Science (1990 to June 2021). Risk of bias for cohort studies was assessed by the Newcastle-Ottawa scale. We pooled risk ratios (RRs) using the DerSimonian-Laird random-effects model for outcomes of those receiving ceftriaxone versus ASAs. Heterogeneity was assessed by the I2 index. From 459 identified studies, 7 were included in the quantitative synthesis totalling 1640 patients. Definitive therapy with ceftriaxone was associated with a lower risk of toxicity requiring therapy alteration (RR 0.49, 95% CI 0.27-0.88; I2 = 0%). There was no difference in terms of 90-day all-cause mortality (RR 0.93, 95% CI 0.46-1.88; I2 = 9%), hospital readmission (RR 0.96, 95% CI 0.57-1.64; I2 = 0%) or infection recurrence (RR 1.04, 95% CI 0.63-1.72; I2 =0%). Current evidence suggests there is no difference in efficacy between ceftriaxone and ASAs for MSSA infection, with a lower risk of toxicity with ceftriaxone. Within the limitations of available retrospective studies, ceftriaxone is a consideration for definitive therapy of MSSA infection. [Trial registration: PROSPERO ID: CRD42021259086].
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Affiliation(s)
- Zachary A Yetmar
- Division of Infectious Diseases, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
| | - Samrah Razi
- Division of Infectious Diseases, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Tarek Nayfeh
- Evidence-Based Practice Research Program, Mayo Clinic, Rochester, Minnesota, USA; Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Mayo Clinic, Rochester, Minnesota, USA
| | - Dana J Gerberi
- Mayo Clinic Libraries, Mayo Clinic, Rochester, Minnesota, USA
| | - Maryam Mahmood
- Division of Infectious Diseases, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Omar M Abu Saleh
- Division of Infectious Diseases, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
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14
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Fisher JF, Mobashery S. β-Lactams against the Fortress of the Gram-Positive Staphylococcus aureus Bacterium. Chem Rev 2021; 121:3412-3463. [PMID: 33373523 PMCID: PMC8653850 DOI: 10.1021/acs.chemrev.0c01010] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The biological diversity of the unicellular bacteria-whether assessed by shape, food, metabolism, or ecological niche-surely rivals (if not exceeds) that of the multicellular eukaryotes. The relationship between bacteria whose ecological niche is the eukaryote, and the eukaryote, is often symbiosis or stasis. Some bacteria, however, seek advantage in this relationship. One of the most successful-to the disadvantage of the eukaryote-is the small (less than 1 μm diameter) and nearly spherical Staphylococcus aureus bacterium. For decades, successful clinical control of its infection has been accomplished using β-lactam antibiotics such as the penicillins and the cephalosporins. Over these same decades S. aureus has perfected resistance mechanisms against these antibiotics, which are then countered by new generations of β-lactam structure. This review addresses the current breadth of biochemical and microbiological efforts to preserve the future of the β-lactam antibiotics through a better understanding of how S. aureus protects the enzyme targets of the β-lactams, the penicillin-binding proteins. The penicillin-binding proteins are essential enzyme catalysts for the biosynthesis of the cell wall, and understanding how this cell wall is integrated into the protective cell envelope of the bacterium may identify new antibacterials and new adjuvants that preserve the efficacy of the β-lactams.
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Affiliation(s)
- Jed F Fisher
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame Indiana 46556, United States
| | - Shahriar Mobashery
- Department of Chemistry and Biochemistry, McCourtney Hall, University of Notre Dame, Notre Dame Indiana 46556, United States
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15
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A Test for the Rapid Detection of the Cefazolin Inoculum Effect in Methicillin-Susceptible Staphylococcus aureus. J Clin Microbiol 2021; 59:JCM.01938-20. [PMID: 33536292 DOI: 10.1128/jcm.01938-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Accepted: 01/23/2021] [Indexed: 11/20/2022] Open
Abstract
The cefazolin inoculum effect (CzIE) has been associated with therapeutic failures and mortality in invasive methicillin-susceptible Staphylococcus aureus (MSSA) infections. A diagnostic test to detect the CzIE is not currently available. We developed a rapid (∼3 h) CzIE colorimetric test to detect staphylococcal-β-lactamase (BlaZ) activity in supernatants after ampicillin induction. The test was validated using 689 bloodstream MSSA isolates recovered from Latin America and the United States. The cefazolin MIC determination at a high inoculum (107 CFU/ml) was used as a reference standard (cutoff ≥16 μg/ml). All isolates underwent genome sequencing. A total of 257 (37.3%) of MSSA isolates exhibited the CzIE by the reference standard method. The overall sensitivity and specificity of the colorimetric test was 82.5% and 88.9%, respectively. Sensitivity in MSSA isolates harboring type A BlaZ (the most efficient enzyme against cefazolin) was 92.7% with a specificity of 87.8%. The performance of the test was lower against type B and C enzymes (sensitivities of 53.3% and 72.3%, respectively). When the reference value was set to ≥32 μg/ml, the sensitivity for isolates carrying type A enzymes was 98.2%. Specificity was 100% for MSSA lacking blaZ The overall negative predictive value ranged from 81.4% to 95.6% in Latin American countries using published prevalence rates of the CzIE. MSSA isolates from the United States were genetically diverse, with no distinguishing genomic differences from Latin American MSSA, distributed among 18 sequence types. A novel test can readily identify most MSSA isolates exhibiting the CzIE, particularly those carrying type A BlaZ. In contrast to the MIC determination using high inoculum, the rapid test is inexpensive, feasible, and easy to perform. After minor validation steps, it could be incorporated into the routine clinical laboratory workflow.
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16
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Buis DTP. Re: 'Comparative outcomes of cefazolin versus anti-staphylococcal penicillins in methicillin-susceptible Staphylococcus aureus infective endocarditis: a post-hoc analysis multicentre French cohort study' by Lecomte et al. Clin Microbiol Infect 2021; 27:1179. [PMID: 33581355 DOI: 10.1016/j.cmi.2021.01.027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 12/15/2022]
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17
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Comparative outcomes of cefazolin versus antistaphylococcal penicillins in methicillin-susceptible Staphylococcus aureus infective endocarditis: a post hoc analysis of a prospective multicentre French cohort study. Clin Microbiol Infect 2020; 27:1015-1021. [PMID: 32950711 DOI: 10.1016/j.cmi.2020.08.044] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/25/2020] [Accepted: 08/30/2020] [Indexed: 12/13/2022]
Abstract
OBJECTIVES Current guidelines recommend cefazolin as an alternative to antistaphylococcal penicillins (ASPs) in methicillin-susceptible Staphylococcus aureus (MSSA) infective endocarditis despite the lack of comparative study. The objective of this study was to evaluate the comparative outcomes of cefazolin vs. ASPs in MSSA infective endocarditis. METHODS This was a retrospective analysis of an observational multicentre cohort study using prospectively collected data from patients with MSSA endocarditis confirmed by endocarditis team and treated either with cefazolin or ASPs between July 2013 and December 2018. Patients were excluded if they received both treatments. The primary outcome was 90-day all-cause mortality. RESULTS Of 210 patients included, 53 patients (25.2%) received cefazolin and 157 (74.8%) received ASPs. The overall 90-day mortality rate was 27.6% (58/210 patients), 24.5% (13/53) in the cefazolin group vs. 28.7% (45/157) in the ASP group (p 0.561). Premature antimicrobial discontinuation due to adverse events occurred less frequently with cefazolin than with ASPs (0/53 vs. 13/157 patients; p 0.042). In multivariate analysis, there was no difference in 90-day mortality between cefazolin and ASPs (adjusted odds ratio (aOR), 1.2; 95% confidence interval (CI), 0.49-2.91; p 0.681), while age (aOR, 1.06; 95% CI, 1.03-1.09; p < 0.001), Charlson comorbidity index (aOR, 1.18; 95% CI, 1.02-1.36 p 0.023), cerebral embolism (aOR, 2.83; 95% CI, 1.33-6.14; p 0.007) and intensive care unit admission (aOR, 4.16; 95% CI, 1.89-9.59; p 0.001) were factors significantly associated with higher mortality. CONCLUSIONS Cefazolin seems to be a possible alternative to ASPs in MSSA endocarditis. More studies are needed to confirm these results and determine which treatment should be recommended as first-line therapy.
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18
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Ulloa ER, Singh KV, Geriak M, Haddad F, Murray BE, Nizet V, Sakoulas G. Cefazolin and Ertapenem Salvage Therapy Rapidly Clears Persistent Methicillin-Susceptible Staphylococcus aureus Bacteremia. Clin Infect Dis 2020; 71:1413-1418. [PMID: 31773134 PMCID: PMC7486850 DOI: 10.1093/cid/ciz995] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 10/20/2019] [Indexed: 11/12/2022] Open
Abstract
Cefazolin and ertapenem combination therapy was used successfully to salvage 11 cases (6 endocarditis) of persistent methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia, including immediate clearance (≤24 hours) in 8 cases. While in vitro synergy was modest, cefazolin plus ertapenem exhibited synergistic action in a rat model of MSSA endocarditis. The combination of cefazolin and ertapenem provides potent in vivo activity against MSSA beyond what is predicted in vitro and warrants further clinical study in the treatment of refractory MSSA bacteremia and endocarditis.
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Affiliation(s)
- Erlinda R Ulloa
- Collaborative to Halt Antibiotic-Resistant Microbes, Department of Pediatrics, University of California, San Diego School of Medicine, La Jolla, California, USA
- Division of Infectious Disease, Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Kavindra V Singh
- Division of Infectious Diseases, Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | | | - Fadi Haddad
- Sharp Grossmont Hospital, La Mesa, California, USA
| | - Barbara E Murray
- Division of Infectious Diseases, Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Victor Nizet
- Collaborative to Halt Antibiotic-Resistant Microbes, Department of Pediatrics, University of California, San Diego School of Medicine, La Jolla, California, USA
- Skaggs School of Pharmacy, University of California, San Diego, La Jolla, California, USA
| | - George Sakoulas
- Collaborative to Halt Antibiotic-Resistant Microbes, Department of Pediatrics, University of California, San Diego School of Medicine, La Jolla, California, USA
- Sharp Memorial Hospital, San Diego, California, USA
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19
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Cefazolin Inoculum Effect and Methicillin-Susceptible Staphylococcus aureus Osteoarticular Infections in Children. Antimicrob Agents Chemother 2020; 64:AAC.00703-20. [PMID: 32660989 DOI: 10.1128/aac.00703-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 06/28/2020] [Indexed: 12/19/2022] Open
Abstract
Select methicillin-susceptible Staphylococcus aureus (MSSA) strains may produce β-lactamases with affinity for first-generation cephalosporins (1GCs). In the setting of a high inoculum, these β-lactamases may promote the cleavage of 1GCs, a phenomenon known as the cefazolin inoculum effect (CzIE). We evaluated the prevalence and impact of CzIE on clinical outcomes among MSSA acute hematogenous osteomyelitis (AHO) cases. MSSA AHO isolates obtained from two children's hospitals between January 2011 and December 2018 were procured through ongoing surveillance studies. Isolates were tested for CzIE via a broth macrodilution assay using an inoculum of 107 CFU/ml; CzIE was defined as a cefazolin MIC of ≥16 μg/ml. Isolates were characterized by accessory gene regulator group (agr). The progression from acute to chronic osteomyelitis was considered an important outcome. A total of 250 cases with viable isolates were included. Notably, 14.4% of isolates exhibited CzIE with no observed temporal trend; and 4% and 76% of patients received a 1GC as an empirical and definitive therapy, respectively. CzIE isolates were more often resistant to clindamycin, belonged to agrIII, and associated with the development of chronic osteomyelitis. In multivariable analyses, agrIII, multiple surgical debridements, delayed source control, and CzIE were independently associated with progression to chronic osteomyelitis. A higher rate of chronic osteomyelitis was observed with CzIE isolates regardless of definitive antibiotic choice. CzIE is exhibited by 14.4% of MSSA AHO isolates in children. CzIE is independently associated with progression to chronic osteomyelitis in cases of AHO irrespective of final antibiotic choice. These data suggest that negative outcomes reported with CzIE may more accurately reflect strain-dependent virulence factors rather than true antibiotic failure.
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20
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Abstract
The phenomenon of attenuated antibacterial activity at inocula above those utilized for susceptibility testing is referred to as the inoculum effect. Although the inoculum effect has been reported for several decades, it is currently debatable whether the inoculum effect is clinically significant. The aim of the present review was to consolidate currently available evidence to summarize which β-lactam drug classes demonstrate an inoculum effect against specific bacterial pathogens. Review of the literature showed that the majority of studies that evaluated the inoculum effect of β-lactams were in vitro investigations of Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Haemophilus influenzae and Staphylococcus aureus. Across all five pathogens, cephalosporins consistently displayed observable inoculum effects in vitro, whereas carbapenems were less susceptible to an inoculum effect. A handful of animal studies were available that validated that the in vitro inoculum effect translates into attenuated pharmacodynamics of β-lactams in vivo. Only a few clinical investigations were available and suggested that an in vitro inoculum effect of cefazolin against MSSA may correspond to an increased likeliness of adverse clinical outcomes in patients receiving cefazolin for bacteraemia. The presence of β-lactamase enzymes was the primary mechanism responsible for an inoculum effect, but the observation of an inoculum effect in multiple pathogens lacking β-lactamase enzymes indicates that there are likely multiple mechanisms that may result in an inoculum effect. Further clinical studies are needed to better define whether interventions made in the clinic in response to organisms displaying an in vitro inoculum effect will optimize clinical outcomes.
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Affiliation(s)
- Justin R Lenhard
- California Northstate University College of Pharmacy, Elk Grove, CA, USA
| | - Zackery P Bulman
- College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
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21
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Sales MJ, Sakoulas G, Szubin R, Palsson B, Arias C, Singh KV, Murray BE, Monk JM. Genome Sequence Comparison of Staphylococcus aureus TX0117 and a Beta-Lactamase-Cured Derivative Shows Increased Cationic Peptide Resistance Accompanying Mutations in relA and mnaA. Microbiol Resour Announc 2020; 9:e01515-19. [PMID: 32354985 PMCID: PMC7193940 DOI: 10.1128/mra.01515-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 03/26/2020] [Indexed: 11/23/2022] Open
Abstract
Staphylococcus aureus strain TX0117 is a methicillin-susceptible bacterium with type A beta-lactamase exhibiting a high cefazolin inoculum effect. TX0117 was cured of blaZ, yielding TX0117c with increased antimicrobial peptide resistance. The sequencing and genome assembly of TX0117 elucidate six mutations between TX0117 and TX0117c, including relA truncation and mnA_1 substitution.
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Affiliation(s)
- Mia Jade Sales
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
| | - George Sakoulas
- Department of Pediatrics, University of California, San Diego School of Medicine, La Jolla, California, USA
| | - Richard Szubin
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
| | - Bernhard Palsson
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
- Department of Pediatrics, University of California, San Diego School of Medicine, La Jolla, California, USA
| | - Cesar Arias
- Division of Infectious Diseases, Department of Internal Medicine, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA
| | - Kavindra V Singh
- Division of Infectious Diseases, Department of Internal Medicine, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA
| | - Barbara E Murray
- Division of Infectious Diseases, Department of Internal Medicine, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA
- Center for Antimicrobial Resistance and Microbial Genomics, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth), Houston, Texas, USA
| | - Jonathan M Monk
- Bioengineering Department, University of California San Diego, La Jolla, California, USA
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22
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Novel Insights into the Classification of Staphylococcal β-Lactamases in Relation to the Cefazolin Inoculum Effect. Antimicrob Agents Chemother 2020; 64:AAC.02511-19. [PMID: 32071048 DOI: 10.1128/aac.02511-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 02/10/2020] [Indexed: 12/19/2022] Open
Abstract
Cefazolin has become a prominent therapy for methicillin-susceptible Staphylococcus aureus (MSSA) infections. However, an important concern is the cefazolin inoculum effect (CzIE), a phenomenon mediated by staphylococcal β-lactamases. Four variants of staphylococcal β-lactamases have been described based on serological methodologies and limited sequence information. Here, we sought to reassess the classification of staphylococcal β-lactamases and their correlation with the CzIE. We included a large collection of 690 contemporary bloodstream MSSA isolates recovered from Latin America, a region with a high prevalence of the CzIE. We determined cefazolin MICs at standard and high inoculums by broth microdilution. Whole-genome sequencing was performed to classify the β-lactamase in each isolate based on the predicted full sequence of BlaZ. We used the classical schemes for β-lactamase classification and compared it to BlaZ allotypes found in unique sequences using the genomic information. Phylogenetic analyses were performed based on the BlaZ and core-genome sequences. The overall prevalence of the CzIE was 40%. Among 641 genomes, type C was the most predominant β-lactamase (37%), followed by type A (33%). We found 29 allotypes and 43 different substitutions in BlaZ. A single allotype, designated BlaZ-2, showed a robust and statistically significant association with the CzIE. Two other allotypes (BlaZ-3 and BlaZ-5) were associated with a lack of the CzIE. Three amino acid substitutions (A9V, E112A, and G145E) showed statistically significant association with the CzIE (P = <0.01). CC30 was the predominant clone among isolates displaying the CzIE. Thus, we provide a novel approach to the classification of the staphylococcal β-lactamases with the potential to more accurately identify MSSA strains exhibiting the CzIE.
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Katkowska M, Garbacz K, Kopala W, Schubert J, Bania J. Genetic diversity and antimicrobial resistance of Staphylococcus aureus from recurrent tonsillitis in children. APMIS 2019; 128:211-219. [PMID: 31692060 DOI: 10.1111/apm.13007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 10/30/2019] [Indexed: 12/14/2022]
Abstract
The aim of this study was to analyze the prevalence of Staphylococcus aureus in the tonsils of children subjected tonsillectomy due to recurrent tonsilitis and to determine the spa types of the pathogens, carriage of virulence genes and antimicrobial resistance profiles. The study included 73 tonsillectomized children. Bacteria, including S. aureus were isolated from tonsillar surface prior to tonsillectomy, recovered from tonsillar core at the time of the surgery, and from posterior pharynx 2-4 weeks after the procedure. Staphylococcus aureus isolates were compared by spa typing, tested for antimicrobial susceptibility and for the presence of superantigenic toxin genes (sea-seu, eta, etb, tst, lukS/lukF-PV) by multiplex polymerase chain reaction. Seventy-three patients (mean 7.1 ± 4.1 years, 61.6% male) were assessed. The most commonly isolated bacteria were S. aureus. The largest proportion of staphylococcal isolates originated from tonsillar core (63%), followed by tonsillar surface (45.1%) and posterior pharynx in tonsillectomized children (18.2%, p = 0.007). Five (6.3%) isolates were identified as MRSA (mecA-positive). Up to 67.5% of the isolates synthesized penicillinases (blaZ-positive isolates), and 8.8% displayed MLSB resistance. The superantigenic toxin genes were detected in more than half of examined isolates (56.3%). spa types t091, t084, and t002, and clonal complexes (CCs) CC7, CC45, and CC30 turned out to be most common. Staphylococcus aureus associated with RT in children showed pathogenicity potential and considerable genetic diversity, and no clones were found to be specific for this condition although further studies are needed.
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Affiliation(s)
- Marta Katkowska
- Department of Oral Microbiology, Faculty of Medicine, Medical University of Gdansk, Gdansk, Poland
| | - Katarzyna Garbacz
- Department of Oral Microbiology, Faculty of Medicine, Medical University of Gdansk, Gdansk, Poland
| | - Wacław Kopala
- Voivodeship Specialist Children's Hospital, Olsztyn, Poland
| | - Justyna Schubert
- Department of Food Hygiene and Consumer Health Protection, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
| | - Jacek Bania
- Department of Food Hygiene and Consumer Health Protection, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
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Stańkowska M, Garbacz K, Piechowicz L, Bronk M. Dissemination Of t437-SCC mecIV And Coagulase-Negative t037-SCC mecIII Types Among Borderline Oxacillin-Resistant Staphylococcus aureus Isolated From Skin Infections And Diabetic Foot Ulcers. Infect Drug Resist 2019; 12:3197-3203. [PMID: 31632105 PMCID: PMC6791403 DOI: 10.2147/idr.s219557] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 09/07/2019] [Indexed: 12/02/2022] Open
Abstract
Background In a recent decade, the occurrence of S. aureus isolates with low-level oxacillin resistance, have been reported increasingly. The aim of this study was to estimate the prevalence of S. aureus with low-level of oxacillin resistance and to determine their molecular characteristics, including spa types, SCCmec types and presence of toxin genes. Methods A total of 249 S. aureus strains were analyzed. Antimicrobial susceptibility was preliminarily tested by the disk diffusion method, and further was verified with the E-test and agar dilution methods. All borderline oxacillin-resistant strains (BORSA) were screened for the mecA gene and virulence factors, including Panton-Valentine leukocidin (PVL). Staphylococcal cassette chromosome mec (SCCmec) typing and spa typing were also carried out. Results Twelve (4.8%) borderline oxacillin-resistant strains with MIC ≤4 µg/mL were identified. Almost all strains (11/12) were oxacillin-susceptible methicillin resistant S. aureus carrying mecA gene (OS-MRSA). Among the 12 bordeline strains, five spa types (t437, t037, t015, t216, t267) and two SCCmec types (III, IV) were identified, with the most prevalent being t437-SCCmecIV pvl-positive. The second most frequent spa type, t037-SCCmecIII, was sea-positive and did not produce coagulase. The majority of borderline strains originated from skin infections and diabetic foot ulcers and were multidrug-resistant (macrolides, lincosamides and chloramphenicol). Conclusion This study demonstrated that S. aureus with borderline resistance to oxacillin represented primarily SCCmecIV spa type t437 and coagulase-negative SCCmecIII spa type t037 and were isolated from skin infections and diabetic foot ulcers.
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Affiliation(s)
- Maria Stańkowska
- Department of Oral Microbiology, Faculty of Medicine, Medical University of Gdansk, Gdansk, Poland
| | - Katarzyna Garbacz
- Department of Oral Microbiology, Faculty of Medicine, Medical University of Gdansk, Gdansk, Poland
| | - Lidia Piechowicz
- Department of Medical Microbiology, Faculty of Medicine, Medical University of Gdansk, Gdansk, Poland
| | - Marek Bronk
- Laboratory of Clinical Microbiology, University Clinical Center, Gdansk, Poland
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Burrelli CC, Broadbent EK, Margulis A, Snyder GM, Gold HS, McCoy C, Mahoney MV, Hirsch EB. Does the Beta-Lactam Matter? Nafcillin versus Cefazolin for Methicillin-Susceptible Staphylococcus aureus Bloodstream Infections. Chemotherapy 2019; 63:345-351. [PMID: 30965335 DOI: 10.1159/000499033] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 02/14/2019] [Indexed: 11/19/2022]
Abstract
BACKGROUND Antistaphylococcal penicillins have historically been regarded as the drugs of choice for methicillin-susceptible Staphylococcus aureus (MSSA) bloodstream infections (BSI). However, recent outcomes data compared to cefazolin treatment are conflicting. OBJECTIVE This study compared treatment failure and adverse effects associated with nafcillin and cefazolin for MSSA BSI. METHODS Adult inpatients with MSSA BSI between January 1, 2009 and August 31, 2015 were included in this retrospective cohort study if they received ≥72 h of nafcillin or cefazolin as directed therapy after no more than 72 h of any empiric therapy. The primary composite endpoint was treatment failure defined by clinician documentation, 30-day recurrence of infection, all-cause 30-day in-hospital mortality, or loss to follow-up. Secondary outcomes included antibiotic-related acute kidney injury (AKI), acute interstitial nephritis (AIN), hepatotoxicity, and rash. RESULTS Among 157 patients, 116 (73.9%) received nafcillin and 41 (26.1%) received cefazolin. The baseline characteristics were similar except cefazolin-treated patients had higher APACHE II scores and more frequent renal dysfunction. No difference in the composite treatment failure outcome (28.4 vs. 31.7%; p = 0.69) was detected between the nafcillin and cefazolin groups, respectively. In a sensitivity analysis excluding patients without known follow-up, there was no significant difference of treatment failure. AKI, AIN, hepatotoxicity, and rash were all numerically more frequent among nafcillin-treated patients. CONCLUSIONS Among nafcillin- or cefazolin-treated patients with MSSA BSI, there was no significant difference in treatment failure. Observing more frequent presumptive adverse effects associated with nafcillin receipt, future prospective studies evaluating cefazolin appear warranted.
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Affiliation(s)
- Corey C Burrelli
- Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.,University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA
| | | | | | - Graham M Snyder
- Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.,University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Howard S Gold
- Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | | | - Monica V Mahoney
- Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Elizabeth B Hirsch
- University of Minnesota College of Pharmacy, Minneapolis, Minnesota, USA,
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Adjunctive Clavulanic Acid Abolishes the Cefazolin Inoculum Effect in an Experimental Rat Model of Methicillin-Sensitive Staphylococcus aureus Endocarditis. Antimicrob Agents Chemother 2018; 62:AAC.01158-18. [PMID: 30150459 DOI: 10.1128/aac.01158-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 08/17/2018] [Indexed: 01/04/2023] Open
Abstract
We tested the ability of clavulanic acid to restore the efficacy of cefazolin against Staphylococcus aureus TX0117, which exhibits the cefazolin inoculum effect (CzIE). In the rat infective endocarditis model, the coadministration of cefazolin plus clavulanic acid resulted in a significant reduction of bacterial counts (7.1 ± 0.5 log10 CFU/g) compared to that with cefazolin alone (2 ± 0.6 log10 CFU/g; P < 0.0001). The addition of a β-lactamase inhibitor may be a viable strategy for overcoming the CzIE.
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