Browsing by Subject "Methicillin-Resistant Staphylococcus aureus"
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Item Open Access A randomized Phase 2 trial of telavancin versus standard therapy in patients with uncomplicated Staphylococcus aureus bacteremia: the ASSURE study.(BMC Infect Dis, 2014-05-23) Stryjewski, Martin E; Lentnek, Arnold; O'Riordan, William; Pullman, John; Tambyah, Paul Anantharajah; Miró, Jose M; Fowler, Vance G; Barriere, Steven L; Kitt, Michael M; Corey, G RalphBACKGROUND: Staphylococcus aureus bacteremia is a common infection associated with significant morbidity and mortality. Telavancin is a bactericidal lipoglycopeptide active against Gram-positive pathogens, including methicillin-resistant S. aureus (MRSA). We conducted a randomized, double-blind, Phase 2 trial in patients with uncomplicated S. aureus bacteremia. METHODS: Patients were randomized to either telavancin or standard therapy (vancomycin or anti-staphylococcal penicillin) for 14 days. Continuation criteria were set to avoid complicated S. aureus bacteremia. The primary end point was clinical cure at 84 days. RESULTS: In total, 60 patients were randomized and 58 received ≥1 study medication dose (all-treated), 31 patients fulfilled inclusion/exclusion and continuation criteria (all-treated target [ATT]) (telavancin 15, standard therapy 16), and 17 patients were clinically evaluable (CE) (telavancin 8, standard therapy 9). Mean age (ATT) was 60 years. Intravenous catheters were the most common source of S. aureus bacteremia and ~50% of patients had MRSA. A similar proportion of CE patients were cured in the telavancin (88%) and standard therapy (89%) groups. All patients with MRSA bacteremia were cured and one patient with MSSA bacteremia failed study treatment in each group. Although adverse events (AEs) were more common in the telavancin ATT group (90% vs. 72%), AEs leading to drug discontinuation were similar (7%) in both treatment arms. Potentially clinically significant increases in serum creatinine (≥1.5 mg/dl and at least 50% greater than baseline) were more common in the telavancin group (20% vs. 7%). CONCLUSIONS: This study suggests that telavancin may have utility for treatment of uncomplicated S. aureus bacteremia; additional studies are warranted. (Telavancin for Treatment of Uncomplicated Staphylococcus Aureus Bacteremia (ASSURE); NCT00062647).Item Open Access CAMERA2 - combination antibiotic therapy for methicillin-resistant Staphylococcus aureus infection: study protocol for a randomised controlled trial.(Trials, 2016-03-31) Tong, Steven YC; Nelson, Jane; Paterson, David L; Fowler, Vance G; Howden, Benjamin P; Cheng, Allen C; Chatfield, Mark; Lipman, Jeffrey; Van Hal, Sebastian; O'Sullivan, Matthew; Robinson, James O; Yahav, Dafna; Lye, David; Davis, Joshua S; CAMERA2 study group and the Australasian Society for Infectious Diseases Clinical Research NetworkBACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia is a serious infection resulting in 20-50 % 90-day mortality. The limitations of vancomycin, the current standard therapy for MRSA, make treatment difficult. The only other approved drug for treatment of MRSA bacteraemia, daptomycin, has not been shown to be superior to vancomycin. Surprisingly, there has been consistent in-vitro and in-vivo laboratory data demonstrating synergy between vancomycin or daptomycin and an anti-staphylococcal β-lactam antibiotic. There is also growing clinical data to support such combinations, including a recent pilot randomised controlled trial (RCT) that demonstrated a trend towards a reduction in the duration of bacteraemia in patients treated with vancomycin plus flucloxacillin compared to vancomycin alone. Our aim is to determine whether the addition of an anti-staphylococcal penicillin to standard therapy results in improved clinical outcomes in MRSA bacteraemia. METHODS/DESIGN: We will perform an open-label, parallel-group, randomised (1:1) controlled trial at 29 sites in Australia, New Zealand, Singapore, and Israel. Adults (aged 18 years or older) with MRSA grown from at least one blood culture and able to be randomised within 72 hours of the index blood culture collection will be eligible for inclusion. Participants will be randomised to vancomycin or daptomycin (standard therapy) given intravenously or to standard therapy plus 7 days of an anti-staphylococcal β-lactam (flucloxacillin, cloxacillin, or cefazolin). The primary endpoint will be a composite outcome at 90 days of (1) all-cause mortality, (2) persistent bacteraemia at day 5 or beyond, (3) microbiological relapse, or (4) microbiological treatment failure. The recruitment target of 440 patients is based on an expected failure rate for the primary outcome of 30 % in the control arm and the ability to detect a clinically meaningful absolute decrease of 12.5 %, with a two-sided alpha of 0.05, a power of 80 %, and assuming 10 % of patients will not be evaluable for the primary endpoint. DISCUSSION: Key potential advantages of adding anti-staphylococcal β-lactams to standard therapy for MRSA bacteraemia include their safety profile, low cost, and wide availability. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02365493 . Registered 24 February 2015.Item Open Access Dalbavancin as an option for treatment of S. aureus bacteremia (DOTS): study protocol for a phase 2b, multicenter, randomized, open-label clinical trial.(Trials, 2022-05) Turner, Nicholas A; Zaharoff, Smitha; King, Heather; Evans, Scott; Hamasaki, Toshimitsu; Lodise, Thomas; Ghazaryan, Varduhi; Beresnev, Tatiana; Riccobene, Todd; Patel, Rinal; Doernberg, Sarah B; Rappo, Urania; Fowler, Vance G; Holland, Thomas L; Antibacterial Resistance Leadership Group (ARLG)Background
Staphylococcus aureus bacteremia is a life-threatening infection and leading cause of infective endocarditis, with mortality rates of 15-50%. Treatment typically requires prolonged administration of parenteral therapy, itself associated with high costs and potential catheter-associated complications. Dalbavancin is a lipoglycopeptide with potent activity against Staphylococcus and a long half-life, making it an appealing potential therapy for S. aureus bacteremia without the need for durable central venous access.Methods
DOTS is a phase 2b, multicenter, randomized, assessor-blinded, superiority, active-controlled, parallel-group trial. The trial will enroll 200 adults diagnosed with complicated S. aureus bacteremia, including definite or possible right-sided infective endocarditis, who have been treated with effective antibiotic therapy for at least 72 h (maximum 10 days) and with subsequent clearance of bacteremia prior to randomization to study treatment. Subjects will be randomized 1:1 to complete their antibiotic treatment course with either two doses of dalbavancin on days 1 and 8, or with a total of 4-8 weeks of standard intravenous antibiotic therapy. The primary objective is to compare the Desirability of Outcome Ranking (DOOR) at day 70 for patients randomized to dalbavancin versus standard of care. Key secondary endpoints include quality of life outcomes and pharmacokinetic analyses of dalbavancin.Discussion
The DOTS trial will establish whether dalbavancin is superior to standard parenteral antibiotic therapy for the completion of treatment of complicated S. aureus bacteremia.Trial registration
US National Institutes of Health ClinicalTrials.gov NCT04775953 . Registered on 1 March 2021.Item Open Access Global initiative for meticillin-resistant Staphylococcus aureus pneumonia (GLIMP): an international, observational cohort study.(The Lancet. Infectious diseases, 2016-12) Aliberti, Stefano; Reyes, Luis F; Faverio, Paola; Sotgiu, Giovanni; Dore, Simone; Dore, Simone; Rodriguez, Alejandro H; Soni, Nilam J; Restrepo, Marcos I; GLIMP investigatorsBackground
Antibiotic resistance is a major global health problem and pathogens such as meticillin-resistant Staphylococcus aureus (MRSA) have become of particular concern in the management of lower respiratory tract infections. However, few data are available on the worldwide prevalence and risk factors for MRSA pneumonia. We aimed to determine the point prevalence of MRSA pneumonia and identify specific MRSA risk factors in community-dwelling patients hospitalised with pneumonia.Methods
We did an international, multicentre study of community-dwelling, adult patients admitted to hospital with pneumonia who had microbiological tests taken within 24 h of presentation. We recruited investigators from 222 hospitals in 54 countries to gather point-prevalence data for all patients admitted with these characteristics during 4 days randomly selected during the months of March, April, May, and June in 2015. We assessed prevalence of MRSA pneumonia and associated risk factors through logistic regression analysis.Findings
3702 patients hospitalised with pneumonia were enrolled, with 3193 patients receiving microbiological tests within 24 h of admission, forming the patient population. 1173 (37%) had at least one pathogen isolated (culture-positive population). The overall prevalence of confirmed MRSA pneumonia was 3·0% (n=95), with differing prevalence between continents and countries. Three risk factors were independently associated with MRSA pneumonia: previous MRSA infection or colonisation (odds ratio 6·21, 95% CI 3·25-11·85), recurrent skin infections (2·87, 1·10-7·45), and severe pneumonia disease (2·39, 1·55-3·68).Interpretation
This multicountry study shows low prevalence of MRSA pneumonia and specific MRSA risk factors among community-dwelling patients hospitalised with pneumonia.Funding
None.Item Open Access Hand hygiene noncompliance and the cost of hospital-acquired methicillin-resistant Staphylococcus aureus infection.(Infect Control Hosp Epidemiol, 2010-04) Cummings, Keith L; Anderson, Deverick J; Kaye, Keith SBACKGROUND: Hand hygiene noncompliance is a major cause of nosocomial infection. Nosocomial infection cost data exist, but the effect of hand hygiene noncompliance is unknown. OBJECTIVE: To estimate methicillin-resistant Staphylococcus aureus (MRSA)-related cost of an incident of hand hygiene noncompliance by a healthcare worker during patient care. DESIGN: Two models were created to simulate sequential patient contacts by a hand hygiene-noncompliant healthcare worker. Model 1 involved encounters with patients of unknown MRSA status. Model 2 involved an encounter with an MRSA-colonized patient followed by an encounter with a patient of unknown MRSA status. The probability of new MRSA infection for the second patient was calculated using published data. A simulation of 1 million noncompliant events was performed. Total costs of resulting infections were aggregated and amortized over all events. SETTING: Duke University Medical Center, a 750-bed tertiary medical center in Durham, North Carolina. RESULTS: Model 1 was associated with 42 MRSA infections (infection rate, 0.0042%). Mean infection cost was $47,092 (95% confidence interval [CI], $26,040-$68,146); mean cost per noncompliant event was $1.98 (95% CI, $0.91-$3.04). Model 2 was associated with 980 MRSA infections (0.098%). Mean infection cost was $53,598 (95% CI, $50,098-$57,097); mean cost per noncompliant event was $52.53 (95% CI, $47.73-$57.32). A 200-bed hospital incurs $1,779,283 in annual MRSA infection-related expenses attributable to hand hygiene noncompliance. A 1.0% increase in hand hygiene compliance resulted in annual savings of $39,650 to a 200-bed hospital. CONCLUSIONS: Hand hygiene noncompliance is associated with significant attributable hospital costs. Minimal improvements in compliance lead to substantial savings.Item Open Access Host gene expression profiling and in vivo cytokine studies to characterize the role of linezolid and vancomycin in methicillin-resistant Staphylococcus aureus (MRSA) murine sepsis model.(PLoS One, 2013) Sharma-Kuinkel, Batu K; Zhang, Yurong; Yan, Qin; Ahn, Sun Hee; Fowler, Vance GLinezolid (L), a potent antibiotic for Methicillin Resistant Staphylococcus aureus (MRSA), inhibits bacterial protein synthesis. By contrast, vancomycin (V) is a cell wall active agent. Here, we used a murine sepsis model to test the hypothesis that L treatment is associated with differences in bacterial and host characteristics as compared to V. Mice were injected with S. aureus USA300, and then intravenously treated with 25 mg/kg of either L or V at 2 hours post infection (hpi). In vivo alpha-hemolysin production was reduced in both L and V-treated mice compared to untreated mice but the reduction did not reach the statistical significance [P = 0.12 for L; P = 0.70 for V). PVL was significantly reduced in L-treated mice compared to untreated mice (P = 0.02). However the reduction of in vivo PVL did not reach the statistical significance in V- treated mice compared to untreated mice (P = 0.27). Both antibiotics significantly reduced IL-1β production [P = 0.001 for L; P = 0.006 for V]. IL-6 was significantly reduced with L but not V antibiotic treatment [P<0.001 for L; P = 0.11 for V]. Neither treatment significantly reduced production of TNF-α. Whole-blood gene expression profiling showed no significant effect of L and V on uninfected mice. In S. aureus-infected mice, L altered the expression of a greater number of genes than V (95 vs. 42; P = 0.001). Pathway analysis for the differentially expressed genes identified toll-like receptor signaling pathway to be common to each S. aureus-infected comparison. Expression of immunomodulatory genes like Cxcl9, Cxcl10, Il1r2, Cd14 and Nfkbia was different among the treatment groups. Glycerolipid metabolism pathway was uniquely associated with L treatment in S. aureus infection. This study demonstrates that, as compared to V, treatment with L is associated with reduced levels of toxin production, differences in host inflammatory response, and distinct host gene expression characteristics in MRSA sepsis.Item Open Access Panton-Valentine leukocidin is not the primary determinant of outcome for Staphylococcus aureus skin infections: evaluation from the CANVAS studies.(PLoS One, 2012) Tong, Amy; Tong, Steven YC; Zhang, Yurong; Lamlertthon, Supaporn; Sharma-Kuinkel, Batu K; Rude, Thomas; Ahn, Sun Hee; Ruffin, Felicia; Llorens, Lily; Tamarana, Ganesh; Biek, Donald; Critchley, Ian; Fowler, Vance GThe impact of Panton-Valentine leukocidin (PVL) on the severity of complicated skin and skin structure infections (cSSSI) caused by Staphylococcus aureus is controversial. We evaluated potential associations between clinical outcome and PVL presence in both methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) isolates from patients enrolled in two large, multinational phase three clinical trials assessing ceftaroline fosamil for the treatment of cSSSI (the CANVAS 1 and 2 programs). Isolates from all microbiologically evaluable patients with monomicrobial MRSA or MSSA infections (n = 473) were genotyped by PCR for pvl and underwent pulsed-field gel electrophoresis (PFGE). Genes encoding pvl were present in 266/473 (56.2%) isolates. Infections caused by pvl-positive S. aureus were associated with younger patient age, North American acquisition, and presence of major abscesses (P<0.001 for each). Cure rates of patients infected with pvl-positive and pvl-negative S. aureus were similar overall (93.6% versus 92.8%; P = 0.72), and within MRSA-infected (94.5% vs. 93.1%; P = 0.67) and MSSA-infected patients (92.2% vs. 92.7%; P = 1.00). This finding persisted after adjustment for multiple patient characteristics. Outcomes were also similar when USA300 PVL+ and non-USA300 PVL+ infections were compared. The results of this contemporary, international study suggest that pvl presence was not the primary determinant of outcome in patients with cSSSI due to either MRSA or MSSA.Item Open Access Persistent Methicilin-Resistant Staphylococcus aureus Bacteremia: Resetting the Clock for Optimal Management.(Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2022-10) Holland, Thomas L; Bayer, Arnold S; Fowler, Vance GA positive follow-up blood culture for methicillin-resistant Staphylococcus aureus (MRSA) while on seemingly appropriate therapy is a common and ominous development. However, the definition and management of persistent MRSA bacteremia is unstandardized. In this Opinion Paper, we identify the presence of bacteremia for > 1 calendar day as a "worry point" that should trigger an intensive diagnostic evaluation to identify metastatic infection sites. Next, we define the duration of MRSA bacteremia that likely constitutes antibiotic failure and outline a potential management algorithm for such patients. Finally, we propose pragmatic clinical trial designs to test treatment strategies for persistent MRSA bacteremia.Item Open Access Potential associations between severity of infection and the presence of virulence-associated genes in clinical strains of Staphylococcus aureus.(PLoS One, 2011-04-26) Gill, Steven R; McIntyre, Lauren M; Nelson, Charlotte L; Remortel, Brian; Rude, Tom; Reller, L Barth; Fowler, Vance GBACKGROUND: The clinical spectrum of Staphylococcus aureus infection ranges from asymptomatic nasal carriage to osteomyelitis, infective endocarditis (IE) and death. In this study, we evaluate potential association between the presence of specific genes in a collection of prospectively characterized S. aureus clinical isolates and clinical outcome. METHODOLOGY/PRINCIPAL FINDINGS: Two hundred thirty-nine S. aureus isolates (121 methicillin-resistant S. aureus [MRSA] and 118 methicillin-susceptible S. aureus [MSSA]) were screened by array comparative genomic hybridization (aCGH) to identify genes implicated in complicated infections. After adjustment for multiple tests, 226 genes were significantly associated with severity of infection. Of these 226 genes, 185 were not in the SCCmec element. Within the 185 non-SCCmec genes, 171 were less common and 14 more common in the complicated infection group. Among the 41 genes in the SCCmec element, 37 were more common and 4 were less common in the complicated group. A total of 51 of the 2014 sequences evaluated, 14 non-SCCmec and 37 SCCmec, were identified as genes of interest. CONCLUSIONS/SIGNIFICANCE: Of the 171 genes less common in complicated infections, 152 are of unknown function and may contribute to attenuation of virulence. The 14 non-SCCmec genes more common in complicated infections include bacteriophage-encoded genes such as regulatory factors and autolysins with potential roles in tissue adhesion or biofilm formation.Item Open Access Transmission of MRSA between companion animals and infected human patients presenting to outpatient medical care facilities.(PLoS One, 2011) Ferreira, Jorge Pinto; Anderson, Kevin L; Correa, Maria T; Lyman, Roberta; Ruffin, Felicia; Reller, L Barth; Fowler, Vance GMethicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen in both human and veterinary medicine. The importance of companion animals as reservoirs of human infections is currently unknown. The companion animals of 49 MRSA-infected outpatients (cases) were screened for MRSA carriage, and their bacterial isolates were compared with those of the infected patients using Pulsed-Field Gel Electrophoresis (PFGE). Rates of MRSA among the companion animals of MRSA-infected patients were compared to rates of MRSA among companion animals of pet guardians attending a "veterinary wellness clinic" (controls). MRSA was isolated from at least one companion animal in 4/49 (8.2%) households of MRSA-infected outpatients vs. none of the pets of the 50 uninfected human controls. Using PFGE, patient-pets MRSA isolates were identical for three pairs and discordant for one pair (suggested MRSA inter-specie transmission p-value = 0.1175). These results suggest that companion animals of MRSA-infected patients can be culture-positive for MRSA, representing a potential source of infection or re-infection for humans. Further studies are required to better understand the epidemiology of MRSA human-animal inter-specie transmission.Item Open Access Variation in the type and frequency of postoperative invasive Staphylococcus aureus infections according to type of surgical procedure.(Infect Control Hosp Epidemiol, 2010-07) Anderson, Deverick J; Arduino, Jean Marie; Reed, Shelby D; Sexton, Daniel J; Kaye, Keith S; Grussemeyer, Chelsea A; Peter, Senaka A; Hardy, Chantelle; Choi, Yong Il; Friedman, Joelle Y; Fowler, Vance GOBJECTIVE: To determine the epidemiological characteristics of postoperative invasive Staphylococcus aureus infection following 4 types of major surgical procedures.design. Retrospective cohort study. SETTING: Eleven hospitals (9 community hospitals and 2 tertiary care hospitals) in North Carolina and Virginia. PATIENTS: Adults undergoing orthopedic, neurosurgical, cardiothoracic, and plastic surgical procedures. METHODS: We used previously validated, prospectively collected surgical surveillance data for surgical site infection and microbiological data for bloodstream infection. The study period was 2003 through 2006. We defined invasive S. aureus infection as either nonsuperficial incisional surgical site infection or bloodstream infection. Nonparametric bootstrapping was used to generate 95% confidence intervals (CIs). P values were generated using the Pearson chi2 test, Student t test, or Wilcoxon rank-sum test, as appropriate. RESULTS: In total, 81,267 patients underwent 96,455 procedures during the study period. The overall incidence of invasive S. aureus infection was 0.47 infections per 100 procedures (95% CI, 0.43-0.52); 227 (51%) of 446 infections were due to methicillin-resistant S.aureus. Invasive S. aureus infection was more common after cardiothoracic procedures (incidence, 0.79 infections per 100 procedures [95%CI, 0.62-0.97]) than after orthopedic procedures (0.37 infections per 100 procedures [95% CI, 0.32-0.42]), neurosurgical procedures (0.62 infections per 100 procedures [95% CI, 0.53-0.72]), or plastic surgical procedures (0.32 infections per 100 procedures [95% CI, 0.17-0.47]) (P < .001). Similarly, S. aureus bloodstream infection was most common after cardiothoracic procedures (incidence, 0.57 infections per 100 procedures [95% CI, 0.43-0.72]; P < .001, compared with other procedure types), comprising almost three-quarters of the invasive S. aureus infections after these procedures. The highest rate of surgical site infection was observed after neurosurgical procedures (incidence, 0.50 infections per 100 procedures [95% CI, 0.42-0.59]; P < .001, compared with other procedure types), comprising 80% of invasive S.aureus infections after these procedures. CONCLUSION: The frequency and type of postoperative invasive S. aureus infection varied significantly across procedure types. The highest risk procedures, such as cardiothoracic procedures, should be targeted for ongoing preventative interventions.