A network meta-analysis of antibiotics for treatment of hospitalised patients with suspected or proven meticillin-resistant Staphylococcus aureus infection

Comparative Efficacy and Safety of Vancomycin, Linezolid, Tedizolid, and Daptomycin in Treating Patients with Suspected or Proven Complicated Skin and Soft Tissue Infections: An Updated Network Meta-Analysis

Introduction

Skin and soft structure infections (SSTIs) caused by methicillin-resistant Staphylococcus aureus (MRSA) pose serious health risks and cause significant cost burdens, and a conclusive recommendation about antibiotics has not yet been generated. Therefore, we performed this updated network meta-analysis to determine the preferred drug for the treatment of MRSA-caused SSTIs.

Methods

We searched PubMed, Embase, and Cochrane Library to identify any potentially eligible randomized controlled trials (RCTs) investigating the comparative efficacy and safety of any two of vancomycin, linezolid, tedizolid, and daptomycin in MRSA-caused SSTIs. All statistical analyses were conducted with RevMan, ADDIS, and STATA software.

Results

Twenty eligible RCTs involving 7804 patients were included for the final analysis. Direct meta-analysis suggested that linezolid was superior to vancomycin in improving clinical (odds ratio [OR], 1.46; 95% confidence interval [CI], 1.07–1.99; P = 0.02) and microbiological (OR, 1.89; 95% CI, 1.24–2.86; P = 0.003) success, which were all confirmed by network meta-analyses. No statistical differences were identified regarding other comparisons. Meanwhile, there were no significant differences between any two antibiotics related to safety. Moreover, ranking probabilities indicated that linezolid had the highest probability of being ranked best in terms of clinical and microbiological success.

Conclusion

Based on the limited evidence, linezolid may be a preferred antibiotic for the treatment of MRSA-caused SSTIs because it showed superiority in clinical and microbiological success without difference regarding safety.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00456-0.

Is there still a role for vancomycin in skin and soft-tissue infections?

PURPOSE OF REVIEW

Skin and soft-tissue infections (SSIs) are among the commonest infections encountered in clinical practice. Spread of methicillin-resistant Staphylococcus aureus SSIs continues to increase in both health care and community settings and presents a challenge for the best treatment choice. Vancomycin has been the mainstay of SSIs treatment, but recently its use has been questioned because of concerns about its efficacy, tolerability, and unfavorable pharmacokinetic/pharmacodynamic profile. The purpose of this review is to establish the current role for vancomycin in light of the literature published from January 2007 to September 2017 on comparison with both old and new alternatives.

RECENT FINDINGS

Meta-analyses show better clinical and microbiological outcomes for drugs approved for the treatment of SSI, including those sustained by methicillin-resistant S. aureus, in the last 10 years than for vancomycin. The newer glycopeptides and linezolid decrease the total treatment costs compared with vancomycin, by reducing the length of stay or avoiding the hospitalization.

SUMMARY

Vancomycin is noninferior in efficacy and safety to all comparator drugs, including the newest on the market. However, the SSI treatment evidence base presents several shortcomings limiting the clinical applicability of the results. High-level clinical trials should be performed to obtain results that can be generalized and applied effectively in clinical practice.

Network meta-analysis and pharmacoeconomic evaluation of antibiotics for the treatment of patients infected with complicated skin and soft structure infection and hospital-acquired or ventilator-associated penumonia

Background

Infections due to methicillin-resistant Staphylococcus aureus (MRSA) cause serious health risks and significant economic burdens and the preferred drugs are still controversial.

Methods

We performed a network meta-analysis (NMA) to compare the efficacy and safety of antibiotics used to treat inpatients with complicated skin and soft structure infections (cSSSI) or hospital-acquired or ventilator-associated pneumonia (HAP/VAP). We also developed a decision tree model to assess the cost-effectiveness of antibiotics.

Results

Forty-nine randomized controlled trials met the inclusion criteria (34 for cSSSI, 15 for HAP/VAP) and compared the efficacy and safety of 16 antibiotics. For cSSSI, NMA indicated that for clinical cure, linezolid was superior than vancomycin (odds ratio (OR) 1.55, 95% confidence interval (CI) 1.19–2.02), while tedizolid (OR 1.39, CI 0.70–2.76) was similar to vancomycin. In terms of safety, there were no significant differences between any two interventions on total adverse events. Based on drug and hospital costs in America, the incremental cost-effectiveness ratios (ICERs) per life-year saved for linezolid and tedizolid compared with vancomycin were US$2833 and US$5523. For HAP/VAP, there were no significant effects either for clinical cure or for safety endpoints between linezolid and vancomycin in NMA. ICERs per life-year saved for linezolid compared with vancomycin were US$2185.

Conclusion

In these clinical trials, considering efficacy, safety, and cost-effectivenes, linezolid and tedizolid showed their superiority in MRSA cSSSI; while linezolid might be recommended to treat MRSA pneumonia. Although vancomycin was not cost-effective in pharmacoeconomic evaluation, it is still the first-line treatment for MRSA infection in the clinical practice. This study might provide new insights of therapeutic choices for patients with MRSA infections whilst awaiting the arrival of higher quality evidence.

Electronic supplementary material

The online version of this article (10.1186/s13756-019-0518-2) contains supplementary material, which is available to authorized users.

Antibiotic therapy for skin and soft tissue infections: a protocol for a systematic review and network meta-analysis

BACKGROUND

Skin and soft tissue infections (SSTIs) in hospital and community settings impose a substantial socio-economic burden. Therapeutic uncertainty due to the availability of a wide range of antibiotics and the need for empirical treatment decisions complicate SSTI clinical management. Completion of numerous pairwise meta-analyses to account for this variability in antibiotics is impractical, and many head-to-head comparisons of potential interest are likely not available. In comparing multiple antibiotics simultaneously, this network meta-analysis aims to identify the antibiotic(s) with the greatest value in the treatment of SSTIs, in terms of patient-important outcomes such as efficacy and safety.

METHODS

We will conduct a systematic review to identify randomized controlled trials of persons with suspected or confirmed SSTI assigned to orally or parenterally administered antibiotic therapy that report results on at least one outcome of interest. We will search MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL), along with trial registries. Our primary outcome of interest is clinical success at the test-of-cure visit. Secondary outcomes may include (1) early clinical success (2-3 days after the therapy starts), (2) mortality, (3) adverse events, (4) treatment duration, and (5) length of hospital stay. Independent reviewers will complete screening of titles, abstracts, and full texts, data extraction, risk of bias assessment (using the Cochrane Risk of Bias tool), and evaluation of the certainty of evidence (using the GRADE approach) in duplicate. We will complete pairwise and network meta-analyses within the Bayesian framework when possible using a random effects model. We will stratify SSTIs by severity into uncomplicated and complicated SSTIs when possible. Subgroup analyses by age, infection type, comorbidity, and suspected or confirmed methicillin-resistant Staphylococcus aureus (MRSA)-associated infection are planned.

DISCUSSION

This study has several strengths compared to previous reviews: inclusion of a wider range of infection types, antibiotics, and outcomes; a comprehensive search strategy; a priori subgroup analyses; application of GRADE; and improved interpretability of findings through visual presentation of results. We hope our findings will inform future research, health care professionals, and policy makers resulting in improved evidence-based clinical management of SSTIs.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018085607.

Clinical outcomes after initial treatment of methicillin-resistant Staphylococcus aureus infections

Objective

To evaluate the clinical outcomes associated with anti-methicillin-resistant Staphylococcus aureus (MRSA) antimicrobials.

Methods

We reviewed a prospective database of 247 consecutive patients with clinically and microbiologically confirmed MRSA infections, hospitalized in 7 Japanese hospitals between April 2014 and March 2015, and treated with anti-MRSA pharmaceuticals. Survival was measured at 30 days. We examined the relationships between initial antimicrobial administered and survival and organ toxicity. HR and 95% CIs were calculated.

Results

Overall 30-day mortality was 12%. The lungs were infected in 105 (41%), skin and soft tissue in 73 (30%), and bones and joints in 21 (9%) patients. Bacteremia complicated the illness in 69 patients (28%). Among 5 pharmaceuticals, vancomycin was prescribed to 174 (71%), linezolid to 38 (16%), teicoplanin to 22 (9%), and daptomycin to 11 (5%) patients. Vancomycin tended to be associated with the lowest survival (HR=2.47; 95% CI=0.93-6.51; P=0.067), particularly in the lung-infected subgroup (HR=4.85; 95% CI=1.12-20.94; P=0.034) after adjustments for baseline illness severity. The incidence of renal dysfunction tended to be higher in patients with trough serum concentrations of vancomycin >15 mg/dL.

Conclusion

In this observational study reflecting real-world conditions, vancomycin was associated with higher 30-day mortality and incidence of kidney dysfunction than other anti-MRSA agents. The significance of the differences observed among antimicrobials other than vancomycin is uncertain.

Comparative efficacy and safety of antibiotics used to treat acute bacterial skin and skin structure infections: Results of a network meta-analysis

OBJECTIVE

This NMA compared the efficacy and safety between IV antibiotics that are used in the current standard of care for managing adult patients (≥18 years of age) with ABSSSI.

METHODS

Comparators were chosen on the basis that both direct and indirect comparisons between the interventions of interest could be performed. Outcomes of the analysis were selected on the basis that they are frequently measured and reported in trials involving ABSSSI patients, and only published randomised control trials of any size and duration and with any blinding status were eligible for inclusion in the analysis. The NMA was performed using both a fixed-effect and random-effect model. Efficacy-related endpoints were (1) clinical treatment success and (2) microbiological success at TOC visit. Safety-related endpoints were (1) number of discontinuations due to AEs/SAEs, (2) patients experiencing AEs, (3) patients experiencing SAEs and (4) all-cause mortality.

RESULTS

Study interventions included daptomycin, dalbavancin, linezolid and tigecycline. Vancomycin was the comparator in all studies, except in two where it was linezolid and teicoplanin. The NMA showed that irrespective of patient subgroup, the likelihood of clinical and microbiological success with dalbavancin was statistically similar to the comparators studied. No statistically significant differences were observed between dalbavancin and any of the comparators in the discontinuation rate due to AEs/SAEs. In contrast, dalbavancin was associated with a significantly lower likelihood of experiencing an AE than linezolid, a significantly lower likelihood of experiencing a SAE than vancomycin and daptomycin, and a significantly lower risk of all-cause mortality than vancomycin, linezolid and tigecycline.

CONCLUSION

Dalbavancin affords a promising, new alternative IV antimicrobial agent which is as effective as traditional therapies, but with the added benefit of enabling clinicians to treat patients with ABSSSI in different organisational settings. Notwithstanding, any introduction of an effective treatment with a differential mode of administration into healthcare systems must be followed by a change in clinical practice and patient management in order to fully achieve desirable economic outcomes.

The Surgical Infection Society Revised Guidelines on the Management of Intra-Abdominal Infection

BACKGROUND

Previous evidence-based guidelines on the management of intra-abdominal infection (IAI) were published by the Surgical Infection Society (SIS) in 1992, 2002, and 2010. At the time the most recent guideline was released, the plan was to update the guideline every five years to ensure the timeliness and appropriateness of the recommendations.

METHODS

Based on the previous guidelines, the task force outlined a number of topics related to the treatment of patients with IAI and then developed key questions on these various topics. All questions were approached using general and specific literature searches, focusing on articles and other information published since 2008. These publications and additional materials published before 2008 were reviewed by the task force as a whole or by individual subgroups as to relevance to individual questions. Recommendations were developed by a process of iterative consensus, with all task force members voting to accept or reject each recommendation. Grading was based on the GRADE (Grades of Recommendation Assessment, Development, and Evaluation) system; the quality of the evidence was graded as high, moderate, or weak, and the strength of the recommendation was graded as strong or weak. Review of the document was performed by members of the SIS who were not on the task force. After responses were made to all critiques, the document was approved as an official guideline of the SIS by the Executive Council.

RESULTS

This guideline summarizes the current recommendations developed by the task force on the treatment of patients who have IAI. Evidence-based recommendations have been made regarding risk assessment in individual patients; source control; the timing, selection, and duration of antimicrobial therapy; and suggested approaches to patients who fail initial therapy. Additional recommendations related to the treatment of pediatric patients with IAI have been included.

SUMMARY

The current recommendations of the SIS regarding the treatment of patients with IAI are provided in this guideline.

Systematic review and network meta-analysis of tedizolid for the treatment of acute bacterial skin and skin structure infections caused by MRSA

BACKGROUND

Tedizolid, the active moiety of tedizolid phosphate, is approved in the United States, the European Union, Canada and a number of other countries for the treatment of acute bacterial skin and skin structure infections (ABSSSI) caused by certain susceptible bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). This network meta-analysis (NMA) evaluates the comparative effectiveness of tedizolid and other antibacterials indicated for the treatment of ABSSSI caused by MRSA.

METHODS

Systematic review of 10 databases was undertaken to inform an NMA to estimate the relative effectiveness of tedizolid and established monotherapy comparators (ceftaroline, daptomycin, linezolid, teicoplanin, tigecycline, vancomycin) for treating MRSA-associated ABSSSI. Randomized controlled trials enrolling adults with ABSSSI or complicated skin and skin structure infections caused by suspected/documented MRSA were eligible for inclusion. Networks were developed based on similarity of study design, patient characteristics, outcome measures and available data. Outcomes of interest included clinical response at end of therapy (EOT), post-therapy evaluation (PTE) or test-of-cure assessment and treatment discontinuations resulting from adverse events (AEs). Bayesian NMA was conducted for each outcome using fixed-effects and random effects models.

RESULTS

Literature searches identified 3,618 records; 15 trials met the inclusion criteria and were considered suitable for NMA comparison. In fixed-effects models, tedizolid had higher odds of clinical response at EOT (odds ratio [OR], 1.7; credible interval, 1.0, 3.0) and PTE than vancomycin (OR, 1.6; credible interval, 1.1, 2.5). No differences in odds of clinical response at EOT or PTE were observed between tedizolid and other comparators. There was no evidence of a difference among treatments for discontinuation due to AEs. Results from random effects and fixed-effects models were generally consistent.

CONCLUSIONS

Tedizolid was superior to vancomycin for clinical response at EOT and PTE. There was no evidence of a difference between tedizolid and other comparators and no evidence of a difference between tedizolid and all comparators when evaluating discontinuation due to AEs. These findings suggest that tedizolid provides an alternative option for the management of serious skin infections caused by suspected or documented MRSA. This study is subject to the limitations inherent in all NMAs, and the results should be interpreted accordingly.

Methicillin-resistant Staphylococcus aureus nosocomial pneumonia: role of linezolid in the People's Republic of China

The burden of methicillin-resistant Staphylococcus aureus (MRSA) nosocomial pneumonia in the People’s Republic of China is high, with methicillin-resistance rates greater than 80% reported for patients with S. aureus pneumonia treated in intensive care units. Historically, vancomycin was the treatment of choice for patients with hospital-acquired MRSA infections. Recent evidence suggests that the minimum inhibitory concentration for vancomycin is increasing. Additionally, patients treated with vancomycin require monitoring of vancomycin trough concentrations and can develop nephrotoxicity. Linezolid is a treatment option for patients with hospital-acquired MRSA infections that can be administered either intravenously or orally. Analysis of data from a worldwide linezolid surveillance program initiated in the year 2004 shows no evidence of increasing linezolid minimum inhibitory concentrations. The clinical efficacy of linezolid for patients with gram-positive, including MRSA, nosocomial pneumonia, was evaluated in numerous studies. In general, results from these studies show higher or similar clinical success with no mortality difference for linezolid compared to vancomycin treated patients. Results from a Phase IV study enrolling patients with MRSA-confirmed nosocomial pneumonia suggest higher clinical cure rates for linezolid compared to vancomycin treated patients. Although acquisition costs are higher for linezolid compared to vancomycin therapy, evidence suggests similar overall medical costs. Cost-analysis results from a Chinese perspective show that linezolid dominated vancomycin therapy for MRSA nosocomial pneumonia in ∼35% of bootstrap simulations whereas vancomycin dominated linezolid in less than 2% of bootstrap simulations. In summary, results from both clinical and economic studies, including studies conducted from a Chinese perspective, support the use of linezolid for the treatment of patients with MRSA nosocomial pneumonia.

In Vitro Activity of Ceftaroline against Staphylococcus aureus Isolated in 2012 from Asia-Pacific Countries as Part of the AWARE Surveillance Program

Ceftaroline, the active metabolite of the prodrug ceftaroline-fosamil, is an advanced-generation cephalosporin with activity against methicillin-resistant Staphylococcus aureus (MRSA). This investigation provides in vitro susceptibility data for ceftaroline against 1,971 S. aureus isolates collected in 2012 from seven countries (26 centers) in the Asia-Pacific region as part of the Assessing Worldwide Antimicrobial Resistance and Evaluation (AWARE) program. Broth microdilution as recommended by the CLSI was used to determine susceptibility. In all, 62% of the isolates studied were MRSA, and the ceftaroline MIC90 for all S. aureus isolates was 2 μg/ml (interpretive criteria: susceptible, ≤1 μg/ml). The overall ceftaroline susceptibility rate for S. aureus was 86.9%, with 100% of methicillin-sensitive S. aureus isolates and 78.8% of MRSA isolates susceptible to this agent. The highest percentages of ceftaroline-nonsusceptible MRSA isolates came from China (47.6%), all of which showed intermediate susceptibility, and Thailand (37.1%), where over half (52.8%) of isolates were resistant to ceftaroline (MIC, 4 μg/ml). Thirty-eight ceftaroline-nonsusceptible isolates (MIC values of 2 to 4 μg/ml) were selected for molecular characterization. Among the isolates analyzed, sequence type 5 (ST-5) was the most common sequence type encountered; however, all isolates analyzed from Thailand were ST-228. Penicillin-binding protein 2a (PBP2a) substitution patterns varied by country, but all isolates from Thailand had the Glu239Lys substitution, and 12 of these also carried an additional Glu447Lys substitution. Ceftaroline-fosamil is a useful addition to the antimicrobial agents that can be used to treat S. aureus infections. However, with the capability of this species to develop resistance to new agents, it is important to recognize and monitor regional differences in trends as they emerge.

In Vitro Activity of Ceftaroline against Staphylococcus aureus Isolates Collected in 2012 from Latin American Countries as Part of the AWARE Surveillance Program

The in vitro activities of ceftaroline and comparators, using broth microdilution, were determined against 1,066 Staphylococcus aureus isolates from hospitalized patients. Seventeen medical centers from Latin American countries contributed isolates. Methicillin-resistant S. aureus (MRSA) percentages ranged from 46% (Brazil) to 62% (Argentina). All methicillin-susceptible S. aureus (MSSA) isolates were susceptible to ceftaroline. Ceftaroline activity against MRSA varied with MIC90s of 0.5 (Venezuela) to 2 (Brazil, Chile, and Colombia) μg/ml, which was the highest MIC value. ST-5 was the most common sequence type.

Comparative efficacy of antibiotics for the treatment of acute bacterial skin and skin structure infections (ABSSSI): a systematic review and network meta-analysis

OBJECTIVE

The objective was to conduct a systematic review and network meta-analysis (NMA) of existing treatments for ABSSSI focusing on the novel lipoglycopeptide oritavancin.

METHODS

EMBASE, MEDLINE, MEDLINE in Process, CENTRAL (Cochrane), and select conferences were searched for randomized controlled trials investigating antimicrobial agents for the treatment of ABSSSI. NMA was used to estimate the odds ratios of the Test-Of-Cure (TOC) and Early Clinical Response (ECR) outcomes for treatments relative to vancomycin in the ITT populations. Sub-group analyses in MRSA and MSSA populations were conducted for TOC; sensitivity analyses investigated the use of the clinically evaluable (CE) populations and the restriction to trials following the recent FDA guidelines for clinical trials.

RESULTS

The systematic review identified 52 trials. The most commonly investigated treatments were vancomycin and linezolid; most trials reported TOC, but not ECR. The posterior mean and 95% credible intervals for odds ratios of TOC for antimicrobial agents relative to vancomycin were: linezolid (1.55; 0.91-2.57), daptomycin (2.18; 0.90-5.42), and oritavancin 1200 mg (1.06; 0.80-1.43). The odds ratio of ECR for oritavancin 1200 mg was 1.02 (0.23-4.33). In the MRSA sub-group the odds ratios relative to vancomycin for TOC were: linezolid (1.55; 0.96-2.46), daptomycin (0.74; 0.13-3.66), and oritavancin 1200 mg (0.94; 0.44-2.02). In the MSSA sub-group they were linezolid (1.36; 0.15-13.34) and oritavancin 1200 mg (0.82; 0.08-7.83). These results were robust to the sensitivity analyses.

CONCLUSIONS

This NMA provides a unified framework for the comparison of all available antimicrobial agents used in the treatment of ABSSSI and is the first to assess the ECR end-point. The results suggest equivalence of clinical efficacy between vancomycin, daptomycin, linezolid, and novel antimicrobial agents including oritavancin for the treatment of ABSSSI at TOC. The wide uncertainty margins indicate the heterogeneity of the available evidence and the need for further research.

Preventive and therapeutic strategies in critically ill patients with highly resistant bacteria

The antibiotic pipeline continues to diminish and the majority of the public remains unaware of this critical situation. The cause of the decline of antibiotic development is multifactorial and currently most ICUs are confronted with the challenge of multidrug-resistant organisms. Antimicrobial multidrug resistance is expanding all over the world, with extreme and pandrug resistance being increasingly encountered, especially in healthcare-associated infections in large highly specialized hospitals. Antibiotic stewardship for critically ill patients translated into the implementation of specific guidelines, largely promoted by the Surviving Sepsis Campaign, targeted at education to optimize choice, dosage, and duration of antibiotics in order to improve outcomes and reduce the development of resistance. Inappropriate antimicrobial therapy, meaning the selection of an antibiotic to which the causative pathogen is resistant, is a consistent predictor of poor outcomes in septic patients. Therefore, pharmacokinetically/pharmacodynamically optimized dosing regimens should be given to all patients empirically and, once the pathogen and susceptibility are known, local stewardship practices may be employed on the basis of clinical response to redefine an appropriate regimen for the patient. This review will focus on the most severely ill patients, for whom substantial progress in organ support along with diagnostic and therapeutic strategies markedly increased the risk of nosocomial infections.

Antibiotic stewardship in orthopaedic surgery: principles and practice

A thorough knowledge of the principles of antibiotic stewardship is a crucial part of high-quality orthopaedic surgical care. These principles include (1) determining appropriate indications for antibiotic administration, (2) choosing the correct antibiotic based on known or expected pathogens, (3) determining the correct dosage, and (4) determining the appropriate duration of treatment. Antibiotic stewardship programs have a multidisciplinary staff that can help guide antibiotic selection and dosage. These programs also perform active surveillance of antimicrobial use and may reduce Clostridium difficile and other drug-resistant bacterial infections by providing expert guidance on judicious antibiotic usage. The emergence of antibiotic-resistant pathogens, the geographical diversity of these infecting pathogens, and the changing patient population require customization of prophylactic regimens to reduce infectious complications. A multidisciplinary approach to antibiotic stewardship can lead to improved patient outcomes and cost-effective medical care.

CPRMethicillin resistant coagulase-negative staphylococci isolated from South Korean ducks exhibiting tremor

Background

We describe coagulase-negative staphylococci (CoNS) isolates collected from ducklings exhibiting tremor in South Korea over the period of 2010 to 2011. Screening of antimicrobial susceptibility and analysis of SCCmec elements of CoNS were also investigated.

Results

Staphylococcus cohnii was the most frequent staphylococcus (9 isolates) and S. sciuri (4 isolates), S. lentus (3 isolate), S. simulans (1 isolate) and S. epidermidis (1 isolate) were also detected. Among the 15 antimicrobials tested in this study, resistance against oxacillin (15 isolates, 83.3%) was most frequently observed, but only one isolate (SNUDS-1) possessed mecA. This isolate was shown to possess SCCmec type III; the type 3 ccr complex and the class A mec complex.

Conclusions

Based on these results, isolate SNUDS-1 was shown to possess SCCmec type III; the type 3 ccr complex and the class A mec complex. Although the SCCmec type III is not predominant in human, MR-CoNS (Methicillin resistance Coagulase-negative staphylococci) in food animals should be monitored to prevent the dissemination of antimicrobial resistance genes and resistant pathogens to the community.