A multicentre, open-label, randomized comparative study of tigecycline versus ceftriaxone sodium plus metronidazole for the treatment of hospitalized subjects with complicated intra-abdominal infections

Effectiveness of Five Antibiotic Regimens for the Treatment of Intra-Abdominal Infection in Bogotá

Background: Intra-abdominal infection (IAI) results in prolonged in-hospital length-of-stay, critical care unit requirements, and multiple surgical procedures. Several antimicrobial agents are available for treatment of IAI. In Colombia, there are no data on the comparative effectiveness of the different regimens used. Patients and Methods: A multicenter retrospective cohort study was completed in four third-level hospitals by comparing treatment effectiveness of five different antibiotic protocols (ampicillin-sulbactam, clindamycin-amikacin, piperacillin-tazobactam, amikacin-metronidazole, and cefuroxime-metronidazole) in patients with a diagnosis of IAI. Analysis was based on a composed outcome of therapeutic failure (change of antibiotic because of no clinical improvement, requirement of surgical re-intervention, post-operative infection, change of antibiotic because of antimicrobial resistance, and in-hospital mortality). Association of each antibiotic protocol to therapeutic failure was assessed through logistic regression analysis. Results: Five hundred ninety-three individuals were included. Two hundred twenty-nine were prescribed ampicillin-sulbactam; 170, clindamycin-amikacin; 77, amikacin-metronidazole; 83, piperacillin-tazobactam; and 34, cefuroxime-metronidazole. Therapeutic failure rate was 22%. Multivariable analysis showed none of the evaluated antibiotic protocols had an association with the primary outcome. Variables having an association for higher risk were age >70 years old (odds ratio [OR], 2.08; 95% confidence interval [CI], 1.04-4.18); complicated IAI (OR, 3.36; 95% CI, 1.4-8.07); and World Society of Emergency Surgery (WSES) Sepsis Severity Score (OR, 1.31; 95% CI, 1.18-1.45). Adequate source control (OR, 0.16; 95% CI, 0.05-0.45) and hospitalization at Health Center 2 (OR, 0.30; 95% CI, 0.14-0.63) were identified as protective factors. Conclusions: There are no differences between the rate of therapeutic failure among the different antibiotic protocols evaluated. This outcome depends heavily on risk factors related to disease severity when surgical intervention occurs.

The efficacy and safety of eravacycline compared with current clinically common antibiotics in the treatment of adults with complicated intra-abdominal infections: A Bayesian network meta-analysis

Background

Eravacycline is a novel, fully synthetic fluorocycline antibiotic for the treatment of adults with complicated intra-abdominal infections (cIAIs). However, the efficacy and safety of eravacycline compared with current clinically common antibiotics remain unknown.

Objective

This study aims to compare the efficacy and safety of eravacycline and other clinically common antibiotics in China, including tigecycline, meropenem, ertapenem, ceftazidime/avibactam+metronidazole, piperacillin/tazobactam, imipenem/cilastatin, and ceftriaxone+metronidazole, for the treatment of adults with cIAIs and to provide a reference for clinical choice.

Methods

The PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were electronically searched to collect clinical randomized controlled studies (RCTs) comparing different antibiotics in the treatment of patients with cIAIs from inception to June 1, 2021. Two reviewers independently screened the literature, extracted data, and evaluated the risk of bias in the included studies.

Results

A total of 4050 articles were initially retrieved, and 25 RCTs were included after screening, involving eight treatment therapies and 9372 patients. The results of network meta-analysis showed that in the intention-to-treat (ITT) population, the clinically evaluable (CE) population, and the microbiologically evaluable (ME) population, the clinical response rate of eravacycline was not significantly different from that of the other 7 therapies (P > 0.05). In terms of microbiological response rate, eravacycline was significantly better than tigecycline [tigecycline vs. eravacycline: RR = 0.82, 95%CI (0.65,0.99)], and there was no significant difference between the other 6 regimens and eravacycline (P > 0.05). In terms of safety, the incidence of serious adverse events, discontinuation rate, and all-cause mortality of eravacycline were not significantly different from those of the other 7 treatment therapies (P > 0.05).

Conclusion

Based on the evidence generated by the current noninferiority clinical trial design, the efficacy and safety of eravacycline for the treatment of adults with cIAIs are not significantly different from those of the other 7 commonly used clinical antibiotics in China. In terms of microbiological response rate, eravacycline was significantly better than tigecycline. In view of the severe multidrug-resistant situation in China, existing drugs have difficulty meeting the needs of clinical treatment, and the new antibacterial drug eravacycline may be one of the preferred options for the treatment of cIAIs in adults.

Infectious Diseases Society of America Guidance on the Treatment of AmpC β-lactamase-Producing Enterobacterales, Carbapenem-Resistant Acinetobacter baumannii, and Stenotrophomonas maltophilia Infections

BACKGROUND

The Infectious Diseases Society of America (IDSA) is committed to providing up-to-date guidance on the treatment of antimicrobial-resistant infections. A previous guidance document focused on infections caused by extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E), carbapenem-resistant Enterobacterales (CRE), and Pseudomonas aeruginosa with difficult-to-treat resistance (DTR-P. aeruginosa). Here, guidance is provided for treating AmpC β-lactamase-producing Enterobacterales (AmpC-E), carbapenem-resistant Acinetobacter baumannii (CRAB), and Stenotrophomonas maltophilia infections.

METHODS

A panel of six infectious diseases specialists with expertise in managing antimicrobial-resistant infections formulated questions about the treatment of AmpC-E, CRAB, and S. maltophilia infections. Answers are presented as suggestions and corresponding rationales. In contrast to guidance in the previous document, published data on optimal treatment of AmpC-E, CRAB, and S. maltophilia infections are limited. As such, guidance in this document is provided as "suggested approaches" based on clinical experience, expert opinion, and a review of the available literature. Because of differences in the epidemiology of resistance and availability of specific anti-infectives internationally, this document focuses on the treatment of infections in the United States.

RESULTS

Preferred and alternative treatment suggestions are provided, assuming the causative organism has been identified and antibiotic susceptibility results are known. Approaches to empiric treatment, duration of therapy, and other management considerations are also discussed briefly. Suggestions apply for both adult and pediatric populations.

CONCLUSIONS

The field of antimicrobial resistance is highly dynamic. Consultation with an infectious diseases specialist is recommended for the treatment of antimicrobial-resistant infections. This document is current as of September 17, 2021 and will be updated annually. The most current versions of IDSA documents, including dates of publication, are available at www.idsociety.org/practice-guideline/amr-guidance-2.0/.

Diagnosis and Management of Intraabdominal Infection: Guidelines by the Chinese Society of Surgical Infection and Intensive Care and the Chinese College of Gastrointestinal Fistula Surgeons

The Chinese guidelines for IAI presented here were developed by a panel that included experts from the fields of surgery, critical care, microbiology, infection control, pharmacology, and evidence-based medicine. All questions were structured in population, intervention, comparison, and outcomes format, and evidence profiles were generated. Recommendations were generated following the principles of the Grading of Recommendations Assessment, Development, and Evaluation system or Best Practice Statement (BPS), when applicable. The final guidelines include 45 graded recommendations and 17 BPSs, including the classification of disease severity, diagnosis, source control, antimicrobial therapy, microbiologic evaluation, nutritional therapy, other supportive therapies, diagnosis and management of specific IAIs, and recognition and management of source control failure. Recommendations on fluid resuscitation and organ support therapy could not be formulated and thus were not included. Accordingly, additional high-quality clinical studies should be performed in the future to address the clinicians' concerns.

IGNITE4: Results of a Phase 3, Randomized, Multicenter, Prospective Trial of Eravacycline vs Meropenem in the Treatment of Complicated Intraabdominal Infections

Background

Increasing antimicrobial resistance among pathogens that cause complicated intraabdominal infections (cIAIs) supports the development of new antimicrobials. Eravacycline, a novel member of the fluorocycline family, is active against multidrug-resistant bacteria including extended-spectrum β-lactamase (ESBL) and carbapenem-resistant Enterobacteriaceae.

Methods

IGNITE4 was a prospective, randomized, double-blind trial. Hospitalized patients with cIAI received either eravacycline 1 mg/kg every 12 hours or meropenem 1 g every 8 hours intravenously for 4–14 days. The primary objective was to demonstrate statistical noninferiority (NI) in clinical cure rates at the test-of-cure visit (25–31 days from start of therapy) in the microbiological intent-to-treat population using a NI margin of 12.5%. Microbiological outcomes and safety were also evaluated.

Results

Eravacycline was noninferior to meropenem in the primary endpoint (177/195 [90.8%] vs 187/205 [91.2%]; difference, –0.5%; 95% confidence interval [CI], –6.3 to 5.3), exceeding the prespecified margin. Secondary endpoints included clinical cure rates in the modified ITT population (231/250 [92.4%] vs 228/249 [91.6%]; difference, 0.8; 95% CI, –4.1, 5.8) and the clinically evaluable population (218/225 [96.9%] vs 222/231 [96.1%]; (difference, 0.8; 95% CI –2.9, 4.5). In patients with ESBL-producing Enterobacteriaceae, clinical cure rates were 87.5% (14/16) and 84.6% (11/13) in the eravacycline and meropenem groups, respectively. Eravacycline had relatively low rates of adverse events for a drug of this class, with less than 5%, 4%, and 3% of patients experiencing nausea, vomiting, and diarrhea, respectively.

Conclusions

Treatment with eravacycline was noninferior to meropenem in adult patients with cIAI, including infections caused by resistant pathogens.

Clinical Trials Registration

NCT01844856.

Article Commentary: The Continued Challenge of Staphylococcus aureus in the Surgical Patient

Staphylococcus aureus continues to be a common pathogen from community-acquired infections and for infections after surgical procedures. A review of the history of this pathogen indicates that it will likely continue to develop new virulence characteristics and that it will continue to develop new patterns of resistance. This presentation addresses the three major areas for surgeons in the future. First, vancomycin is losing its effectiveness against methicillin-resistant S. aureus (MRSA). The future antibiotic choices for treating this pathogen are discussed. Second, vancomycin is losing its effectiveness for prevention of MRSA infections at the surgical site, and another antibiotic choice needs to be developed for prevention of both methicillin-sensitive and methicillin-resistant staphylococci. Third, decolonization of staphylococci from the nasopharynx is discussed commonly in the literature, but valid evidence for this practice is limited. Controlled clinical trials to prevent surgical site infection by decolonization with mupirocin or other agents are needed. In summary, S. aureus will continue to challenge surgeons as an adaptable pathogen that can defy all of our treatment efforts.

Systematic Review and Meta-Analysis of the Efficacy of Appropriate Empiric Anti-Enterococcal Therapy for Intra-Abdominal Infection

Background: Delayed treatment of seriously infected patients results in increased mortality. However, antimicrobial therapy for the initial 24 to 48 hours is mostly empirically provided, without evidence regarding the causative pathogen. Whether empiric anti-enterococcal therapy should be administered to treat intra-abdominal infection (IAI) before obtaining culture results remains unknown. We performed a meta-analysis to explore the effects of empiric enterococci covered antibiotic therapy in IAI and the risk factors for enterococcal infection in IAI. Methods: We searched multiple databases systematically and included 23 randomized controlled trials (RCTs) and 13 observational studies. The quality of included studies was assessed, and the reporting bias was evaluated. Meta-analysis was performed using random effects or fixed effects models according to the heterogeneity. The risk ratio (RR), odds ratio (OR), and 95% confidence interval (CI) were calculated. Results: Enterococci-covered antibiotic regimens provided no improvement in treatment success compared with control regimens (RR, 0.99; 95% CI, 0.97-1.00; p = 0.15), with similar mortality and adverse effects in both arms. Basic characteristic analysis revealed that most of the enrolled patients with IAI in RCTs were young, lower risk community-acquired intra-abdominal infection (CA-IAI) patients with a relatively low APACHE II score. Interestingly, risk factor screening revealed that malignancy, corticosteroid use, operation, any antibiotic treatment, admission to intensive care unit (ICU), and indwelling urinary catheter could predispose the patients with IAI to a substantially higher risk of enterococcal infection. "Hospital acquired" itself was a risk factor (OR, 2.81; 95% CI, 2.34-3.39; p < 0.001). Conclusion: It is unnecessary to use additional agents empirically to specifically provide anti-enterococcal coverage for the management of CA-IAI in lower risk patients without evidence of causative pathogen, and risk factors can increase the risk of enterococcal infection. Thus, there is a rationale for providing empiric anti-enterococcal coverage for severely ill patients with CA-IAI with high risk factors and patients with hospital-acquired intra-abdominal infection (HA-IAI).

Cost-effectiveness analysis comparing ceftazidime/avibactam (CAZ-AVI) as empirical treatment comparing to ceftolozane/tazobactam and to meropenem for complicated intra-abdominal infection (cIAI)

Background

The rising incidence of resistance to currently available antibiotics among pathogens, particularly Gram-negative pathogens, in complicated intra-abdominal infections (cIAIs) has become a challenge for clinicians. Ceftazidime/avibactam (CAZ-AVI) is a fixed-dose antibiotic approved in Europe and the United States for treating (in combination with metronidazole) cIAI in adult hospitalised patients who have limited or no alternative treatment options. The approval was based on the results of RECLAIM, a Phase III, parallel-group, comparative study (RECLAIM 1 [NCT01499290] and RECLAIM 2 [NCT01500239]). The objective of our study was to assess the cost-effectiveness of CAZ-AVI plus metronidazole compared with 1) ceftolozane/tazobactam plus metronidazole and 2) meropenem, as an empiric treatment for the management of cIAI in Italy.

Methods

A sequential, patient-level simulation model, with a 5-year time horizon and 3% annual discount rate (applied to both costs and health benefits), was developed using Microsoft Excel® to demonstrate the clinical course of the disease. The impact of resistant pathogens was included as an additional factor.

Results

In the base-case analysis, the CAZ-AVI sequence (CAZ-AVI plus metronidazole followed by a colistin + tigecycline + high-dose meropenem combination after treatment failure), when compared to sequences for ceftolozane/tazobactam (ceftolozane/tazobactam plus metronidazole followed by colistin + tigecycline + high-dose meropenem after treatment failure) and meropenem (meropenem followed by colistin + tigecycline + high-dose meropenem after treatment failure), had better clinical outcomes with higher cure rates (93.04% vs. 91.52%; 92.98% vs. 90.24%, respectively), shorter hospital stays (∆ = − 0.38 and ∆ = − 1.24 days per patient, respectively), and higher quality-adjusted life years (QALYs) gained per patient (4.021 vs. 3.982; 4.019 vs. 3.960, respectively). The incremental cost effectiveness ratio in the CAZ-AVI sequence was €4099 and €15,574 per QALY gained versus each comparator sequence, respectively, well below the willingness-to-pay threshold of €30,000 per QALY accepted in Italy.

Conclusions

The model results demonstrated that CAZ-AVI plus metronidazole could be a cost-effective alternative when compared with other antibiotic treatment options, as it is expected to provide better clinical benefits in hospitalised patients with cIAI in Italy.

Busting the Myth of "Static vs Cidal": A Systemic Literature Review

We sought to determine if clinical data validate the dogma that bactericidal antibiotics are more clinically effective than bacteriostatic agents. We performed a systematic literature review of published, randomized, controlled trials (RCTs) that compared a bacteriostatic agent to a bactericidal agent in the treatment of clinical, bacterial infections. Of 56 identified trials published since 1985, 49 found no significant difference in efficacy between bacteriostatic and bactericidal agents. In 6 trials it was found that the bacteriostatic agent was superior to the bactericidal agent in efficacy. Only 1 trial found that the bactericidal agent was superior; in that case, the inferiority of the static agent was explainable by underdosing of the drug based on pharmacokinetic-pharmacodynamic analysis. Thus, virtually all available data from high-quality, RCTs demonstrate no intrinsic superiority of bactericidal compared to bacteriostatic agents. Other drug characteristics such as optimal dosing, pharmacokinetics, and tissue penetration may be more important efficacy drivers.

Eravacycline: a new treatment option for complicated intra-abdominal infections in the age of multidrug resistance

Aim: Recently approved for use in complicated intra-abdominal infection, eravacycline is a novel fluorocycline with broad spectrum of activity against resistant Gram-negative pathogens. This manuscript is a pooled analysis of two Phase III trials. Clinical efficacy: Clinical cure rates were 86.8% for eravacycline versus 87.6% for ertapenem, and 90.8% for eravacycline versus 91.2% for meropenem in the Intent to Treat (micro-ITT) populations, and 87.0% for eravacycline versus 88.8% ertapenem, and 92.4 versus 91.6% for meropenem in the Modified Intent to Treat (MITT) populations. Safety: Eravacycline is well tolerated, with lower rates of nausea, vomiting and diarrhea than other tetracyclines. Conclusion: Eravacycline is an effective new option for use in complicated intra-abdominal infections, and in particular, for the treatment of extended-spectrum β-lactamase- and carbapenem-resistant Enterobacteriaceae-expressing organisms.

A Retrospective Analysis of the Effect of Tigecycline on Coagulation Function

A number of clinical trials demonstrated that tigecycline was effective and well tolerated in the treatment of patients with various bacterial infections, but few literatures had shown the coagulopathy induced by tigecycline. To address this concern, we performed a retrospective analysis to assess the impact of tigecycline treatment on coagulation parameters in 50 patients with bacterial infections in our hospital (Shandong Provincial Hospital, China). These patients were treated with tigecycline at Shandong Provincial Hospital in 2015-2016 at either a recommended (50 mg q12h) or a higher dose (100 mg q12h). Coagulation parameters, including Fibrinogen (FIB) levels, prothrombin time (PT), activated partial thromboplastin time (aPTT), platelet count (PLT) and D-dimer, were evaluated in order to assess the impact of tigecycline treatment in these severely infected patients. What we found was that the plasma fibrinogen (FIB) level was 4.63 ± 1.56 g/L before tigecycline treatment, and decreased to 2.92 ± 1.23 g/L during treatment, which was statistically significant (p < 0.001). The mean values of aPTT and PT were significantly increased from 39.58 ± 8.72 to 44.05 ± 10.45 s (p = 0.002), and from 15.37 ± 1.53 to 16.37 ± 2.64 s (p = 0.004), respectively. This study demonstrates that treatment of tigecycline could reduce FIB, prolong aPTT and PT. In conclusion, we advise that it is necessary for practitioners routinely monitor coagulation level in at-rick patient populations treated with tigecycline.

A multicenter, double-blind, randomized, comparison study of the efficacy and safety of tigecycline to imipenem/cilastatin to treat complicated intra-abdominal infections in hospitalized subjects in China

Purpose

To assess the efficacy and safety of tigecycline in treating complicated intra-abdominal infections (cIAIs) in hospitalized patients in China.

Patients and methods

A Phase IV, multicenter, randomized, double-blinded, active-controlled, non-inferiority study was conducted. Hospitalized cIAI patients ≥18 years of age were randomized (1:1) to receive intravenous tigecycline (initial dose 100 mg, then 50 mg q12h) or imipenem/cilastatin (500 mg/500 mg or adjusted for renal dysfunction, q6h) for 5–14 days. The primary end point was clinical response for clinically evaluable (CE) subjects at test-of-cure (TOC) assessment.

Results

Four hundred and seventy subjects were randomized; 232 in the tigecycline and 231 in the imipenem/cilastatin group were treated. Tigecycline was non-inferior to imipenem/cilastatin with respect to clinical response at TOC for all CE subjects, ie, the lower bound of the two-sided 95% CI (−12.0%, −1.4%) for the treatment difference in cure rate, tigecycline (89.9%) minus imipenem/cilastatin (96.6%), was >−15%. As non-inferiority was concluded in the CE population, superiority of tigecycline over imipenem/cilastatin and superiority of imipenem/cilastatin over tigecycline were tested on the CE and the modified intent-to-treat (mITT) populations according to pre-specified statistical criteria, and neither could be demonstrated (the cure rate was 82.8% vs 88.7%, difference −6.0% [−12.8%, 0.8%], for the mITT population). The subject-level microbiological response rate at TOC for the microbiologically evaluable population was 88.0% (110/125) vs 95.3% (102/107, difference −7.3% [−15.2%, 0.5%]). Nausea, drug ineffectiveness, postoperative wound infection, vomiting, and pyrexia were the most common adverse events in tigecycline-treated subjects; pyrexia, nausea, vomiting, and increased alanine aminotransferase and aspartate aminotransferase levels were most common in imipenem/cilastatin-treated subjects; none were unanticipated.

Conclusion

Tigecycline was non-inferior to imipenem/cilastatin in treating hospitalized adult patients with cIAI. Superiority of tigecycline over imipenem/cilastatin or imipenem/cilastatin over tigecycline could not be demonstrated. Safety was consistent with the known profile for tigecycline.

ClinicalTrials.gov identifier

NCT01721408.

Efficacy of intravenous tigecycline in patients with Acinetobacter complex infections: results from 14 Phase III and Phase IV clinical trials

Background

Acinetobacter infections, especially multidrug-resistant (MDR) Acinetobacter infections, are a global health problem. This study aimed to describe clinical outcomes in patients with confirmed Acinetobacter spp. isolates who were treated with tigecycline in randomized clinical trials.

Materials and methods

Data from 14 multinational, randomized (open-label or double-blind), and active-controlled (except one) Phase III and IV studies were analyzed using descriptive statistics.

Results

A total of 174 microbiologically evaluable patients with Acinetobacter spp. infections (including MDR infections) were identified, and 95 received tigecycline to treat community-acquired pneumonia (CAP), diabetic foot infections (DFIs), hospital-acquired pneumonia (HAP), complicated intra-abdominal infections (cIAIs), infections with resistant pathogens (RPs), or complicated skin and skin-structure infections. The rate of cure of tigecycline for most indications was 70%–80%, with the highest (88.2%) in cIAIs. The rate of cure of the comparators was generally higher than tigecycline, but within each indication the 95% CIs for clinical cure for each treatment group overlapped. For most Acinetobacter isolates, the minimum inhibitory concentration of tigecycline was 0.12–2 μg/mL, with seven at 4 μg/mL and one at 8 μg/mL. The cure rate by tigecycline was 50% (95% CI 12.5%–87.5% in CAP) to 88.2% (95% CI 66.2%–97.1% in cIAIs) for all Acinetobacter, and 72.7% (95% CI 54.5%–93.2% in HAP) to 100% (95% CI 25%–100.0% in cIAIs) for MDR Acinetobacter. For the comparators, it was 83.8% (95% CI 62.8%–95.9% in HAP) to 100% (95% CI 75%–100% in cIAIs and 25%–100.0% in RPs) and 88% (95% CI 66%–97% in HAP) to 100% (95% CI 25%–100% in cIAIs and 75%–100% in DFIs), respectively.

Conclusion

These findings suggest that with appropriate monitoring, tigecycline may be a useful consideration for Acinetobacter infections alone or in combination with other anti-infective agents when other therapies are not suitable.

The efficacy of combined therapy with metronidazole and broad-spectrum antibiotics on postoperative outcomes for pediatric patients with perforated appendicitis

The aim of this study was to evaluate the efficacy of combined therapy with metronidazole and broad-spectrum antibiotics for patients with perforated appendicitis who underwent surgical intervention.Broad-spectrum antibiotic therapy is warranted in the treatment of perforated appendicitis. Metronidazole has been used as anaerobic antimicrobial therapy. However, few studies about the use of metronidazole in perforated appendicitis have been reported.The medical records of 249 patients treated with metronidazole combined with broad-spectrum antibiotics following perforated appendicitis surgery were reviewed retrospectively and compared with the medical records of 149 patients treated only with broad-spectrum antibiotics. Propensity score matching was performed to adjust for selected baseline variables. Clinical outcomes, including postoperative complications and length of hospital stay, were compared between the 2 groups.No differences were found between the use of combined therapy with metronidazole and the use of solely broad-spectrum antibiotic agents with regard to postoperative duration of intravenous antibiotic treatment (6.8 ± 1.3 vs 7.9 ± 2.1 days, respectively, P = .18), inflammation variables at POD 5 (white blood cell [WBC] [risk ratio [RR], 1.06; 95% confidence interval [CI], 0.67-1.93, P = .15] and C-reactive protein [CRP] [RR, 1.18; 95% CI, 0.73-2.25, P = .36]) (Table 2), and the mean postoperative length of hospital stay (LOS) (RR, 0.68, 95% CI, 0.41-0.94, P = .41). There were also no differences in the incidence of postoperative complications, including the intra-abdominal or pelvic abscess rate (7[7.1%] vs 9[9.2%], respectively, P = .40), the incidence of wound infection (14[14.3%] vs 15[15.3%], respectively, P = .50), and the 30-day readmission rate (9[9.2%] vs 12[12.2%], respectively, P = .32).Regarding overall postoperative outcomes and complications, our study demonstrated no beneficial clinical effects of metronidazole administration in patients with perforated appendicitis who underwent surgical intervention. Therefore, metronidazole is not indicated when broad-spectrum antibiotics such as aminopenicillins with β-lactam inhibitors or carbapenems and select cephalosporins are used.

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.

Retrospective analysis of tigecycline shows that it may be an option for children with severe infections

AIM

This study assessed the efficacy and safety of tigecycline in children with life-threatening infections.

METHODS

We retrospectively reviewed the clinical records of patients treated with tigecycline from June 2012 to May 2014 in a Chinese tertiary centre.

RESULTS

The study comprised 24 patients (14 male) with a median age of four years (range, 50 days-12 years). The most frequently isolated microorganism, most common isolation site and type of infection were Acinetobacter baumannii, tracheal aspirate fluid and ventilator-associated pneumonia, respectively. Tigecycline was administered at a loading dose of 1.5 or 2.0 mg/kg and 1.0 mg/kg every 12 hours after that. The average duration of treatment was 11.6 ± 5.8 days. The clinical response and microbiological eradication rate were 37.5% and 29.2%, respectively. Six of the patients we studied (25.0%) died, and three of these deaths were considered to be infection related. Adverse drug reactions were identified in four patients (16.7%) during the treatment, including abnormal liver function, prolonged prothrombin time and diarrhoea.

CONCLUSION

Our findings suggest that tigecycline may be an option for children with severe infections. However, more prospective, controlled trials are required to objectively evaluate the efficacy and safety of tigecycline in children.

Optimal Treatment for Complicated Intra-abdominal Infections in the Era of Antibiotic Resistance: A Systematic Review and Meta-Analysis of the Efficacy and Safety of Combined Therapy With Metronidazole

Background.  Carbapenem-resistant Enterobacteriaceae has increased dramatically in the last decade, resulting in infections that are difficult to treat and associated with high mortality rates. To prevent further antibacterial resistance, it is necessary to use carbapenem selectively. A combination of metronidazole with an antimicrobial agent active against aerobes is an alternative effective treatment for patients with complicated intra-abdominal infections (cIAIs). This study aimed to compare efficacy and safety of metronidazole combination therapies and carbapenem and to provide clinical evidence regarding the optimal treatment of cIAI. Methods.  A systematic review and a meta-analysis of randomized clinical trials in the treatment of cIAI were conducted. The systematic review with PubMed, Embase, and the Cochrane Database of Systematic Reviews followed the Cochrane Handbook's recommended methodology, and the meta-analysis used a Mantel-Haenszel random-effects model with RevMan, version 5.3. Primary endpoints were clinical success and bacteriological eradication, and secondary endpoints were all-cause mortality and drug-related adverse events. Results.  Eight studies comparing metronidazole combination therapies and carbapenem were included in the meta-analysis. No difference was found between combined therapy with metronidazole and carbapenem regarding clinical success (odds ratio [OR] = 1.31; 95% confidence interval [CI], .75-2.31), bacteriological eradication (OR = 1.27; 95% CI, .84-1.91), all-cause mortality (OR = 0.61; 95% CI, .37-1.00), or drug-related adverse events (OR = 0.58; 95% CI, .18-1.88). Sensitivity analyses found similar results. Conclusions.  Combined therapy with metronidazole is as effective and safe as carbapenem in treatment of cIAI. Therefore, combined therapy with metronidazole offers an effective alternative to carbapenem with low risk of drug resistance.

Spectrum adequacy of antibiotic regimens for secondary peritonitis: a retrospective analysis in intermediate and intensive care unit patients

Background

Secondary peritonitis requires surgical source control and adequate antimicrobial treatment. Antimicrobial regimens are usually selected according to local susceptibility data of individual pathogens against single agents, but this neglects both the polymicrobial nature of the infection and the use of combination therapy. We analysed the probability of common regimens to cover all relevant pathogens isolated in one patient (“spectrum adequacy rate”, SAR) in a real-life data set.

Methods

Data from 242 patients with secondary peritonitis (88 community acquired, 154 postoperative cases) treated in our IMCU/ICU were obtained retrospectively. The relative frequency of pathogens, resistance rates and the SAR were analysed using the free software R.

Results

Enterococci were isolated in 47.1 % of all patients, followed by Escherichia coli (42.6 %), other enterobacteriaceae (33.1 %), anaerobes (29.8 %) and Candida spp. (28.9 %). Resistance patterns were consistent with general surveillance data from our hospital. The susceptibility rates and SAR were lower in postoperative than in community acquired cases. The following regimens yielded a SAR > 95 % when enterobacteriaceae only were considered: piperacillin/tazobactam + gentamicin, cefotaxim (only for community acquired cases), cefotaxim + gentamicin, meropenem, tigecycline + gentamicin or tigecycline + ciprofloxaxin. When enterococci were also considered, all betalactam based regimens required combination with vancomycin or linezolid for a SAR > 95 %, whereas TGC based regimens were not compromised. As for Candida spp., the SAR of fluconazole was 81.9–87.5 %.

Conclusions

This study demonstrates a rational approach to assess the adequacy of antimicrobial regimens in secondary peritonitis, which may help to adjust local guidelines or to select candidate regimens for clinical studies.

Efficacy and safety of tigecycline for the treatment of severe infectious diseases: an updated meta-analysis of RCTs

OBJECTIVES

To assess the efficacy and safety of tigecycline in comparison with other antimicrobial treatments for infectious diseases.

DESIGN

Databases of PubMed, Embase and the Cochrane Library were searched through Feb. 2015. The reference lists of the initially identified articles and systemic review articles were manually searched. Randomized controlled trials assessing tigecycline and other antibiotics for infectious diseases in adult patients were included.

RESULTS

Fifteen RCTs including 7689 cases were identified. We found that tigecycline was not as effective as the comparator agents for clinical treatment success (for the clinically evaluable population, odds ratio [OR] = 0.83, 95% confidence interval [CI] = (0.73, 0.96), P=0.01; for the clinically modified intent-to-treat (mITT) population, OR = 0.81, 95% CI = (0.72, 0.92), P=0.001). There was no significant difference in microbiological treatment success with lower eradication rate in tigecycline versus comparators (for the microbiologically evaluable population, OR = 0.94, 95% CI = (0.77, 1.16), P=0.56; for the microbiological mITT populations, OR = 0.91, 95% CI = (0.74, 1.11), P=0.35). Adverse events and all-cause mortality were more common in the tigecycline group.

CONCLUSIONS

Tigecycline is not as effective as other antibiotics with relatively more frequency of adverse events and higher mortality rate.

Clinical response and mortality in tigecycline complicated intra-abdominal infection and complicated skin and soft-tissue infection trials

An imbalance in all-cause mortality was noted in tigecycline phase 3 and 4 comparative clinical trials across all studied indications. We investigated clinical failure and mortality in phase 3 and 4 complicated skin and soft-tissue infection (cSSTI) and complicated intra-abdominal infection (cIAI) tigecycline trials using descriptive analyses of a blinded adjudication of mortality and multivariate regression analyses. Attributable mortality analyses of cSSTI revealed death due to infection in 0.1% of each treatment group (P=1.000). In cIAI, there were no significant differences between tigecycline (1.2%) and comparator (0.7%) subjects who died due to infection (P=0.243). For cIAI clinical failure, treatment interaction with organ dysfunction was observed with no difference observed between clinical cure for tigecycline (85.4%) and comparator (76.7%) treatment groups (odds ratio=0.58, 95% confidence interval 0.28-1.19). Tigecycline-treated subjects had more adverse events of secondary pneumonias (2.1% vs. 1.2%) and more adverse events of secondary pneumonias with an outcome of death (0.5% vs. 0.1%). These analyses do not suggest that tigecycline is a factor either for failure (cSSTI and cIAI studies) or for death (cIAI studies).

Clinical characteristics of ceftriaxone plus metronidazole in complicated intra-abdominal infection

Purpose

Empirical antibiotics in complicated intra-abdominal infection (c-IAI), such as secondary peritonitis are a first step of treatment. Empirical antibiotic regimen is very diverse. Ceftriaxone plus metronidazole regimen (CMR) is one of the empirical antibiotic regimens used in treatment of c-IAI. However, although CMR is a widely used empirical antibiotic regimen, study regarding success, failure or efficacy of CMR has been poorly understood. This retrospective study is conducted to compare the clinical efficacy of this regimen in c-IAI according to clinical characteristics.

Methods

The subjects were patients in this hospital who were diagnosed as secondary peritonitis between 2009 and 2013. Retrospective analysis was performed based on the records made after surgery regarding clinical characteristics including albumin level, blood pressure, pulse rate, respiration rate, smoking, age, sex, body mass index, hemoglobin, coexisting disease, leukocytosis, and APACHE (acute physiology and chronic health evaluation) II score.

Results

A total of 114 patients were enrolled. In univariated analysis, the success and failure of CMR showed significant association with preoperative low albumin, old age, and preoperative tachycardia. In multivariated analysis, low albumin and preoperative tachycardia were significant.

Conclusion

It is thought that an additional antibiotic treatment plan is necessary in patients with low albumin and tachycardia when the empirical antibiotic regimen is CMR in c-IAI. Conduct of research through well-designed prospective randomized clinical study is also necessary in order to evaluate the appropriateness of CMR and decide on a proper empirical antibiotic regimen between many regimens in c-IAI based on our country.

Guidelines for management of intra-abdominal infections

Intra-abdominal infections are one of the most common gastrointestinal emergencies and a leading cause of septic shock. A consensus conference on the management of community-acquired peritonitis was published in 2000. A new consensus as well as new guidelines for less common situations such as peritonitis in paediatrics and healthcare-associated infections had become necessary. The objectives of these Clinical Practice Guidelines (CPGs) were therefore to define the medical and surgical management of community-acquired intra-abdominal infections, define the specificities of intra-abdominal infections in children and describe the management of healthcare-associated infections. The literature review was divided into six main themes: diagnostic approach, infection source control, microbiological data, paediatric specificities, medical treatment of peritonitis, and management of complications. The GRADE(®) methodology was applied to determine the level of evidence and the strength of recommendations. After summarising the work of the experts and application of the GRADE(®) method, 62 recommendations were formally defined by the organisation committee. Recommendations were then submitted to and amended by a review committee. After 2 rounds of Delphi scoring and various amendments, a strong agreement was obtained for 44 (100%) recommendations. The CPGs for peritonitis are therefore based on a consensus between the various disciplines involved in the management of these patients concerning a number of themes such as: diagnostic strategy and the place of imaging; time to management; the place of microbiological specimens; targets of empirical anti-infective therapy; duration of anti-infective therapy. The CPGs also specified the value and the place of certain practices such as: the place of laparoscopy; the indications for image-guided percutaneous drainage; indications for the treatment of enterococci and fungi. The CPGs also confirmed the futility of certain practices such as: the use of diagnostic biomarkers; systematic relaparotomies; prolonged anti-infective therapy, especially in children.

Clinical and economic consequences of failure of initial antibiotic therapy for patients with community-onset complicated intra-abdominal infections

Objectives

Complicated intra-abdominal infection (cIAI) is infection that extends beyond the hollow viscus of origin into the peritoneal space, and is associated with either abscess formation or peritonitis. There are few studies that have assessed the actual costs and outcomes associated with failure of initial antibiotic therapy for cIAI. The aims of this study were to evaluate risk factors and impact on costs and outcomes of failure of initial antibiotic therapy for community-onset cIAI.

Methods

A retrospective study was performed at eleven tertiary-care hospitals. Hospitalized adults with community-onset cIAI who underwent an appropriate source control procedure between August 2008 and September 2011 were included. Failure of initial antibiotic therapy was defined as a change of antibiotics due to a lack of improvement of the clinical symptoms and signs associated with cIAI in the first week.

Results

A total of 514 patients hospitalized for community-onset cIAI were included in the analysis. The mean age of the patients was 53.3 ± 17.6 years, 72 patients (14%) had health care-associated infection, and 48 (9%) experienced failure of initial antibiotic therapy. Failure of initial antibiotic therapy was associated with increased costs and morbidity. After adjustment for covariates, patients with unsuccessful initial therapy received an additional 2.9 days of parenteral antibiotic therapy, were hospitalized for an additional 5.3 days, and incurred $3,287 in additional inpatient charges. Independent risk factors for failure of initial antibiotic therapy were health care-associated infection, solid cancer, and APACHE II ≥13.

Conclusions

To improve outcomes and costs in patients with community-onset cIAI, rapid assessment of health care-associated risk factors and severity of disease, selection of an appropriate antibiotic regimen accordingly, and early infection source control should be performed.

Tigecycline use in critically ill patients: a multicentre prospective observational study in the intensive care setting

PURPOSE

This prospective observational study aimed at describing prescription patterns of tigecycline and patient outcomes in 26 French intensive care units (ICU).

METHODS

Data of consecutive cases of adult patients treated with tigecycline were collected from the initiation until 7 days after the end of treatment. Response to treatment was classified as success, failure or undetermined and analyses were presented according to severity (SOFA score <7 or ≥7). Survival was recorded at 28 days.

RESULTS

A total of 156 patients were included (64% male, age 60 ± 15 years). At inclusion, 53% had a SOFA score ≥7; 93% had received prior anti-infective agents. Tigecycline was given as first-line treatment in 47% of patients, mostly in combination (67%), for intra-abdominal (IAI 56%), skin and soft tissue (SSTI 19%) or other infections. A total of 76% of the treated infections were hospital-acquired. Bacteraemia was reported in 12% of patients. Median treatment duration was 9 days. Tigecycline was prematurely stopped in 42% patients. The global success rate was 60% at the end of treatment, and significantly higher with treatment duration more than 9 days (76 vs. 47%, P < 0.001). Success rate was 65% for patients alive at the end of treatment. Success rates tended to decrease with illness severity, immunosuppression, bacteraemia and obesity. Survival rate at day 28 was 85% in the whole cohort and significantly higher in the less severely ill patients (P < 0.001).

CONCLUSIONS

Tigecycline success rates appear comparable to those reported in clinical studies in ICU with severe infections. Tigecycline could be an alternative in ICU patients.

Efficacy of tigecycline for the treatment of complicated intra-abdominal infections in real-life clinical practice from five European observational studies

OBJECTIVES

Tigecycline is a broad-spectrum antibiotic approved for the treatment of complicated intra-abdominal infections (cIAIs). The efficacy of tigecycline when administered as monotherapy or in combination with other antibacterials in the treatment of cIAIs in routine clinical practice is described.

PATIENTS AND METHODS

Individual patient-level data were pooled from five European observational studies (July 2006 to October 2011).

RESULTS

A total of 785 cIAI patients who received tigecycline were included (mean age 63.1 ± 14.0 years). Of these, 56.6% were in intensive care units, 65.6% acquired their infection in hospital, 88.1% had at least one comorbidity and 65.7% had secondary peritonitis. The mean Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores at the beginning of treatment were 16.9 ± 7.6 (n = 614) and 7.0 ± 4.2 (n = 108), respectively, indicating high disease severity. Escherichia coli (41.8%), Enterococcus faecium (40.1%) and Enterococcus faecalis (21.1%) were the most frequently isolated pathogens; 49.1% of infections were polymicrobial and 17.5% were due to resistant pathogens. Overall, 54.8% (n = 430) received tigecycline as monotherapy and 45.2% (n = 355) as combination therapy for a mean duration of 10.6 days. Clinical response rates at the end of treatment were 77.4% for all patients (567/733), 80.6% for patients who received tigecycline as monotherapy (329/408), 75.2% for patients with a nosocomial infection (354/471), 75.8% for patients with an APACHE II score >15 (250/330) and 54.2% (32/59) for patients with a SOFA score ≥ 7.

CONCLUSIONS

In these real-life studies, tigecycline, alone and in combination, achieved favourable clinical response rates in patients with cIAI with a high severity of illness.

Resistance mechanisms and epidemiology of multiresistant pathogens in Europe and efficacy of tigecycline in observational studies

OBJECTIVES

Antimicrobial drug resistance is a growing problem in Europe and, even with differences in epidemiology, it is of great concern. The treatment of complicated skin and soft-tissue infections (cSSTIs) and complicated intra-abdominal infections (cIAIs) is hindered further by pathogens that are resistant to methicillin, carbapenems, third-generation cephalosporins and glycopeptides.

PATIENTS AND METHODS

An analysis of the microbiological results from five European observational studies (July 2006 to October 2011) evaluating the efficacy of tigecycline (prescribed as monotherapy or in combination with other antibacterials) for the treatment of cSSTI and cIAI is presented.

RESULTS

In total, 213 cSSTI and 623 cIAI patients were included; 34.4% and 56.6%, respectively, were critically ill in intensive care units. At baseline, at least one pathogen was isolated in 167 (78.4%) cSSTI and 464 (74.5%) cIAI patients, and 32.9% and 49.1% of infections were polymicrobial. In cSSTI, Staphylococcus aureus and Escherichia coli (52.7% and 18.0%, respectively) were the most frequently isolated pathogens, whereas in cIAI most infections were due to E. coli (41.8%), Enterococcus faecium (40.1%) and Enterococcus faecalis (21.1%). Clinical response was observed in >80% of patients with E. coli in both cIAI and cSSTI. In cSSTI patients, the clinical response rate to S. aureus was 80.8%. For cIAI, 77.4% of E. faecium and 79.5% of E. faecalis patients responded to treatment.

CONCLUSIONS

Tigecycline when given alone or in combination with other antibacterials appeared to be efficacious against multiple pathogens, affirming its role in real-life clinical practice as a broad-spectrum antibacterial for the treatment of patients with cSSTI and cIAI, including the critically ill, across Europe.

Tigecycline treatment of infection caused by KPC-producing Escherichia coli in a pediatric patient

Tigecycline shows great antimicrobial activity against both Gram-positive and Gram-negative bacteria, and has been considered to be an appropriate choice in controlling infection caused by multi-drug resistant (MDR) pathogens, such as carbapenemase-producing Enterobacteriaceae (CPE). Although many clinical trials evaluate the efficacy and safety of tigecycline on adults, rare reports recommend tigecycline to treat pediatric patient. In this study, we presented a clinical case with tigecycline as an anti-infectious agent on a 14-year-old child who was suffering from infection of intraperitoneal abscess caused by Klebsiella pneumoniae carbapenemases (KPC)-producing Escherichia coli with extreme drug resistant profile. By accessing the clinical outcome and efficacy of the patient, and the side effects of tigecycline, our research explored the documented experience of tigecycline on controlling infection caused by CPE isolate in children.

In vitro activity of tigecycline and comparators against organisms associated with intra-abdominal infections collected as part of TEST (2004-2009)

As part of the Tigecycline Evaluation and Surveillance Trial (TEST), bacterial isolates were collected consecutively from centers globally between 2004 and 2009. MICs were determined locally using Clinical and Laboratory Standards Institute broth microdilution methodology. A total of 3114 anaerobic and 99,256 aerobic isolates were included in this study. The most active agents against Gram-negative anaerobes were metronidazole and meropenem (resistance ranges 0.0-0.5% and 0.0-0.9%, respectively); piperacillin-tazobactam was also active (resistance range 0.5-9.4%). Among Gram-positive anaerobes, resistance rates were lowest for meropenem, piperacillin-tazobactam, and metronidazole (ranges 0.0-0.5%, 0.0-1.8%, and 0.0-3.2% respectively). Tigecycline MIC(90) values for anaerobes ranged from 0.12 to 2 μg/mL. The most active antimicrobial agent against Gram-negative aerobes (excluding Pseudomonas aeruginosa) was tigecycline, with resistance ranging from <0.01% to 1.4%. Resistance was also low for imipenem (0.3-9.4%) and meropenem (0.7-15.1%). Extended-spectrum beta-lactamases were produced by 12.2% and 19.7% of E. coli and K. pneumoniae isolates, respectively.

Excess deaths associated with tigecycline after approval based on noninferiority trials

BACKGROUND

On the basis of noninferiority trials, tigecycline received Food and Drug Administration (FDA) approval in 2005. In 2010, the FDA warned in a safety communication that tigecycline was associated with an increased risk of death.

METHODS

PubMed, EMBASE, Scopus, and ClinicalTrials.gov were searched using the terms "tigecycline" and "randomized controlled trial (RCT)" through April 2011. Excess deaths and noncure rates for both approved and nonapproved indications were examined using meta-analysis.

RESULTS

Ten published and 3 unpublished studies met inclusion criteria (N = 7434). No significant heterogeneity was seen for mortality (I(2 )= 0%; P = .99) or noncure rates (I(2 )= 25%; P = .19). Across randomized controlled trials, tigecycline was associated with increased mortality (risk difference [RD], 0.7%; 95% confidence interval [CI], 0.1%-1.2%; P = .01) and noncure rates (RD, 2.9%; 95% CI, 0.6%-5.2%; P = .01). Effects were not isolated to type of infection or comparator antibiotic regimen, and the impact on survival remained significant when limited to trials of approved indications (I(2 )= 0%; RD, 0.6%; P = .04). A pooled analysis of the 5 trials completed by early 2005 before tigecycline was approved would have demonstrated a similar harmful effect of tigecycline on survival (I(2 )= 0%; RD, 0.7%; P = .06).

CONCLUSIONS

Pooling noninferiority studies to examine survival may help ensure the safety and efficacy of new antibiotics. The association of tigecycline with excess deaths and noncure includes indications for which it is approved and marketed. Tigecycline cannot be relied on in serious infections.

Efficacy and safety of tigecycline for the treatment of infectious diseases: a meta-analysis

BACKGROUND

Multidrug resistance among bacteria increases the need for new antimicrobial drugs with high potency and stability. Tigecycline is one candidate drug, and a previous meta-analysis of only published randomised controlled trials suggested that it might as effective as comparator treatments; we did a meta-analysis to include new and unpublished trials to assess its efficacy for the treatment of adult patients with serious bacterial infection.

METHODS

We searched PubMed, Cochrane Central Register, and Embase up to March 30, 2011, to identify published studies, and we searched clinical trial registries to identify completed unpublished studies, the results of which were obtained through the manufacturer. Eligible studies were randomised trials assessing the clinical efficacy, safety, and eradication efficiency of tigecycline versus other antimicrobial agents for any bacterial infection. The primary outcome was treatment success in patients who received at least one dose of the study drug, had clinical evidence of disease, and had complete follow-up (the clinically assessable population). Meta-analysis was done with random-effects models because of heterogeneity across the trials.

FINDINGS

14 randomised trials, comprising about 7400 patients, were included. Treatment success was lower with tigecycline than with control antibiotic agents, but the difference was not significant (odds ratio 0·87, 95% CI 0·74-1·02). Adverse events were more frequent in the tigecycline group than in the control groups (1·45, 1·11-1·88), with significantly more vomiting and nausea. All-cause mortality was higher in the tigecycline group than in the comparator groups, but the difference was not significant (1·28, 0·97-1·69). Eradication efficiency did not differ between tigecycline and control regimens, but the sample size for these comparisons was small.

INTERPRETATION

Tigecycline is not better than standard antimicrobial agents for the treatment of serious infections. Our findings show that assessment with unpublished studies is needed to make appropriate decisions about new agents.

FUNDING

None.

Efficacy and safety of tigecycline: a systematic review and meta-analysis

BACKGROUND

Tigecycline is a novel glycylcycline that exhibits broad-spectrum antibacterial activity. Recently, the US FDA issued a warning concerning increased mortality with tigecycline in randomized controlled trials (RCTs).

METHODS

We conducted a systematic review and meta-analysis of RCTs that compared tigecycline with any other antibiotic regimen for the treatment of any infection. A comprehensive search, without publication status or other restrictions, was conducted. The primary outcome was overall 30 day mortality. The secondary outcome included clinical and microbiological failure, superinfections and adverse events (AEs). The trials' risks of bias and their effects on results were assessed. Two reviewers independently extracted the data. Individual trials' relative risks (RRs) were pooled using a fixed effect meta-analysis.

RESULTS

Fifteen trials (7654 patients) were included. Overall mortality was higher with tigecycline compared with other regimens [RR 1.29, 95% confidence interval (CI) 1.02-1.64, without heterogeneity]. The type of infection assessed and the trials' reported risks of bias did not affect this result. Clinical failure was significantly higher with tigecycline (RR 1.16, 95% CI 1.06-1.27) and non-statistically significant higher rates of microbiological failure were demonstrated (RR 1.13, 95% CI 0.99-1.30). Development of septic shock was significantly more frequent with tigecycline (RR 7.01, 95% CI 1.27-38.66). Superinfections were significantly more common with tigecycline and so were AEs, including all AEs and AEs requiring discontinuation.

CONCLUSIONS

In the light of the increased mortality, probably explained by decreased clinical and microbiological efficacy, clinicians should avoid tigecycline monotherapy in the treatment of severe infections and reserve it as a last-resort drug.

WSES consensus conference: Guidelines for first-line management of intra-abdominal infections

Intra-abdominal infections are still associated with high rate of morbidity and mortality.A multidisciplinary approach to the management of patients with intra-abdominal infections may be an important factor in the quality of care. The presence of a team of health professionals from various disciplines, working in concert, may improve efficiency, outcome, and the cost of care.A World Society of Emergency Surgery (WSES) Consensus Conference was held in Bologna on July 2010, during the 1st congress of the WSES, involving surgeons, infectious disease specialists, pharmacologists, radiologists and intensivists with the goal of defining recommendations for the early management of intra-abdominal infections.This document represents the executive summary of the final guidelines approved by the consensus conference.

Systematic review and meta-analysis of the effectiveness and safety of tigecycline for treatment of infectious disease

The aim of this study was to compare the efficacy and safety of tigecycline, a newly developed glycylcycline antibiotic, with those of empirical antibiotic regimens which have been reported to possess good efficacy for complicated skin and skin structure infections (cSSSIs), complicated intra-abdominal infections (cIAIs), community-acquired pneumonia (CAP), and other infections caused by methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE). A meta-analysis of randomized controlled trials (RCTs) identified in PubMed, the Cochrane Library, and Embase was performed. Eight RCTs involving 4,651 patients were included in the meta-analysis. Compared with therapy with empirical antibiotic regimens, tigecycline monotherapy was associated with similar clinical treatment success rates (for the clinically evaluable [CE] population, odds ratio [OR] = 0.92, 95% confidence interval [CI] = 0.76 to 1.12, P = 0.42; for the clinical modified intent-to-treat [c-mITT] population, OR = 0.86, 95% CI = 0.74 to 1.01, P = 0.06) and similar microbiological treatment success rates (for the microbiologically evaluable [ME] population, OR = 0.86, 95% CI = 0.69 to 1.07, P = 0.19). The incidence of adverse events in the tigecycline group was significantly higher than that in the other therapy groups with a statistical margin (for the modified intent-to-treat [mITT] population, OR = 1.33, 95% CI = 1.17 to 1.52, P < 0.0001), especially in the digestive system (mITT population, OR = 2.41, 95% CI = 1.67 to 3.46, P < 0.00001). No difference regarding all-cause mortality and drug-related mortality between tigecycline and the other regimens was found, although numerically higher mortality was found in the tigecycline group. This meta-analysis provides evidence that tigecycline monotherapy may be used as effectively as the comparison therapy for cSSSI, cIAIs, CAP, and infections caused by MRSA/VRE. However, because of the high risk of mortality, AEs, and emergence of resistant isolates, prudence with the clinical use of tigecycline monotherapy in infections is required.