Sequential intravenous/oral moxifloxacin versus intravenous piperacillin-tazobactam followed by oral amoxicillin-clavulanate for the treatment of complicated skin and skin structure infection

Treatment of clinically uninfected diabetic foot ulcers, with and without antibiotics

OBJECTIVE

Current guidelines do not recommend the use of antibiotics to treat clinically uninfected ulcers. However, physicians continue to prescribe antibiotics for clinically uninfected ulcers with the rationale 'better to be safe than sorry'. Yet, antibiotic resistance is increasing, side-effects are common and treatment costs are rising. Evidence is needed to identify whether antibiotic treatment for clinically uninfected ulcers can be justified or we should stop prescribing them. The aim of this study was to evaluate whether antibiotic treatment in cases of clinically uninfected ulcers improved ulcer healing compared to treatment without antibiotics.

METHOD

Consecutive patients treated in the outpatient clinic for clinically uninfected diabetic foot ulcer both in 2015 and in 2017 were retrospectively analysed. Primary outcome was ulcer healing at one year. Secondary outcomes were limb salvage, freedom from any amputation, amputation-free survival (AFS) and survival.

RESULTS

A total of 102 ulcers of 91 patients were included for final analyses. The non-antibiotics and antibiotics groups both consisted of 51 ulcers. Ulcer healing at one year was 77.3% in the non-antibiotics group and 74.7% in the antibiotics group (p=0.158). No difference was found for limb salvage (93.8% versus 95.9%, respectively; p=0.661), freedom from any amputation (85.6% versus 85.6%, respectively; p=1.000), AFS (85.4% versus 79.1%, respectively; p=0.460) or survival (89.6% versus 83.7%, respectively; p=0.426).

CONCLUSION

In this study, no benefits of antibiotic treatment over non-antibiotic treatment for clinically uninfected ulcers were identified. The findings of this study emphasise the recommendation of current guidelines to not treat clinically uninfected ulcer with antibiotics.

Systemic Antimicrobial Therapy for Diabetic Foot Infections: An Overview of Systematic Reviews

Diabetic foot infections (DFIs) are a common complication of diabetes; however, there is clinical uncertainty regarding the optimal antimicrobial selection. The aim of this review was to critically evaluate the recent systematic reviews on the efficacy and safety of systemic (parenteral or oral) antimicrobials for DFI. Medline, Embase, CENTRAL, and CINAHL databases and the PROSPERO register were searched from January 2015 to January 2023. Systematic reviews with or without meta-analyses on systemic antimicrobials for DFI, with outcomes of clinical infection resolution or complications, were included. Of the 413 records identified, 6 systematic reviews of 29 individual studies were included. Heterogeneity of individual studies precluded meta-analysis, except for ertapenem versus piperacillin-tazobactam (RR 1.07, 95% CI [0.96-1.19]) and fluoroquinolones versus piperacillin-tazobactam (RR 1.03, 95% CI [0.89-1.20]) in one review. The application of the AMSTAR-2 tool determined two reviews to be of high quality. There was no statistical difference in the clinical resolution of infections for 24 different antimicrobial regimens (penicillins, cephalosporins, carbapenems, fluoroquinolones, vancomycin, metronidazole, clindamycin, linezolid, daptomycin, and tigecycline). However, tigecycline did not meet non-inferiority against ertapenem ± vancomycin (absolute difference -5.5%, 95% CI [-11.0-0.1]) and was associated with a higher incidence of adverse drug events. There is minimal systematic review evidence to suggest one regimen is superior to another for DFI.

The Epidemiology of Antibiotic-Related Adverse Events in the Treatment of Diabetic Foot Infections: A Narrative Review of the Literature

The use of antibiotics for the treatment of diabetic foot infections (DFIs) over an extended period of time has been shown to be associated with adverse events (AEs), whereas interactions with concomitant patient medications must also be considered. The objective of this narrative review was to summarize the most frequent and most severe AEs reported in prospective trials and observational studies at the global level in DFI. Gastrointestinal intolerances were the most frequent AEs, from 5% to 22% among all therapies; this was more common when prolonged antibiotic administration was combined with oral beta-lactam or clindamycin or a higher dose of tetracyclines. The proportion of symptomatic colitis due to Clostridium difficile was variable depending on the antibiotic used (0.5% to 8%). Noteworthy serious AEs included hepatotoxicity due to beta-lactams (5% to 17%) or quinolones (3%); cytopenia's related to linezolid (5%) and beta-lactams (6%); nausea under rifampicin, and renal failure under cotrimoxazole. Skin rash was found to rarely occur and was commonly associated with the use of penicillins or cotrimoxazole. AEs from prolonged antibiotic use in patients with DFI are costly in terms of longer hospitalization or additional monitoring care and can trigger additional investigations. The best way to prevent AEs is to keep the duration of antibiotic treatment short and with the lowest dose clinically necessary.

Is coverage of S. aureus necessary in cellulitis/erysipelas? A literature review

BACKGROUND

Empirical treatment of patients with cellulitis/erysipelas usually targets both streptococci and methicillin-sensitive S. aureus (MSSA). However, the recommendation to empirically cover MSSA is weak and based on low-quality evidence.

METHODS AND OBJECTIVE

A systematic review was conducted in PubMed and clinical trial registries to assess the role of S. aureus in cellulitis/erysipelas and the need for empirical MSSA coverage.

RESULTS

Combined microbiological and serological data, and response to penicillin monotherapy suggest that streptococci are responsible for the vast majority of cases of cellulitis/erysipelas. However, most cases are non-culturable and the specificity of microbiological and serological studies is questionable based on recent studies using molecular techniques. According to epidemiological data and three randomized controlled trials, empirical coverage of methicillin-resistant S. aureus (MRSA) is not recommended for most patients, despite the high prevalence of MRSA in many areas. If MRSA is indeed not an important cause of uncomplicated cellulitis/erysipelas, then the same may apply to MSSA. Based on indirect comparison of data from clinical studies, cure rates with penicillin monotherapy (to which most MSSA are resistant) are comparable to the cure rates reported in many studies using wider-spectrum antibiotics.

CONCLUSION

Considering the limitations of microbiological studies in identifying the pathogens responsible for cellulitis/erysipelas, treatment needs to be guided by clinical trials. Trials comparing penicillin or amoxicillin monotherapy to MSSA-covering regimens are needed to definitively answer whether empirical coverage of MSSA is needed and to identify the subset of patients that can be safely treated with penicillin or amoxicillin monotherapy.

Assessment of Antibiotic Treatment of Cellulitis and Erysipelas: A Systematic Review and Meta-analysis

Importance

The optimum antibiotic treatment for cellulitis and erysipelas lacks consensus. The available trial data do not demonstrate the superiority of any agent, and data are limited on the most appropriate route of administration or duration of therapy.

Objective

To assess the efficacy and safety of antibiotic therapy for non-surgically acquired cellulitis.

Data Sources

The following databases were searched to June 28, 2016: Cochrane Central Register of Controlled Trials (2016, issue 5), Medline (from 1946), Embase (from 1974), and Latin American and Caribbean Health Sciences Information System (LILACS) (from 1982). In addition, 5 trials databases and the reference lists of included studies were searched. Further searches of PubMed and Google Scholar were undertaken from June 28, 2016, to December 31, 2018.

Study Selection

Randomized clinical trials comparing different antibiotics, routes of administration, and treatment durations were included.

Data Extraction and Synthesis

For data collection and analysis, the standard methodological procedures of the Cochrane Collaboration were used. For dichotomous outcomes, the risk ratio and its 95% CI were calculated. A summary of findings table was created for the primary end points, adopting the GRADE approach to assess the quality of the evidence.

Main Outcomes and Measures

The primary outcome was the proportion of patients cured, improved, recovered, or symptom-free or symptom-reduced at the end of treatment, as reported by the trial. The secondary outcome was any adverse event.

Results

A total of 43 studies with a total of 5999 evaluable participants, whose age ranged from 1 month to 96 years, were included. Cellulitis was the primary diagnosis in only 15 studies (35%), and in other studies the median (interquartile range) proportion of patients with cellulitis was 29.7% (22.9%-50.3%). Overall, no evidence was found to support the superiority of any 1 antibiotic over another, and antibiotics with activity against methicillin-resistant Staphylococcus aureus did not add an advantage. Use of intravenous antibiotics over oral antibiotics and treatment duration of longer than 5 days were not supported by evidence.

Conclusions and Relevance

In this systematic review and meta-analysis, only low-quality evidence was found for the most appropriate agent, route of administration, and duration of treatment for patients with cellulitis; future trials need to use a standardized set of outcomes, including severity scoring, dosing, and duration of therapy.

Clinical efficacy of piperacillin/tazobactam in the treatment of complicated skin and soft tissue infections

INTRODUCTION

Complicated skin and soft tissue infections (cSSTIs) are skin and soft tissue infections (SSTIs) that involve deep soft tissue. cSSTIs often require surgical intervention and/or hospitalization. cSSTIs are associated with significant mortality and morbidity, and carry a significant burden on health care systems. Piperacillin/tazobactam has been regarded as a standard treatment for cSSTIs because of its antibiotic spectrum, safety and clinical efficacy. Several antibiotics, as compared to piperacillin/tazobactam, have been evaluated in the treatment of cSSTIs. Areas covered: This review summarizes randomized controlled trials (RCTs) evaluating the clinical efficacy of piperacillin/tazobactam for the treatment of cSSTIs. Expert opinion: Piperacillin/tazobactam, which covers most causative organisms in cSSTIs, is the drug of choice for the treatment of cSSTIs. Other options such as ertapenem and moxifloxacin may be reasonable where multiple daily dosing or intravenous administration is inappropriate. But in general, they should be avoided as an empirical treatment because of their highly association with resistant bacteria, which are becoming a global threat. Therefore, piperacilin/tazobactam is appropriate as an empirical therapy for the treatment of SSTIs and should be de-escalated as soon as causative organisms are identified, their drug-sensitivity results are available, and clinical condition becomes stable.

Failure of antibiotics in cellulitis trials: a systematic review and meta-analysis

OBJECTIVES

The objectives of the study are to quantify trial-to-trial variability in antibiotic failure rates, in randomized clinical trials of cellulitis treatment and to provide a point estimate for the treatment failure rate across trials.

METHODS

We conducted a structured search for clinical trials evaluating antibiotic treatment of cellulitis, indexed in PubMed by August 2015. We included studies published in English and excluded studies conducted wholly outside of developed countries because the pathophysiology of cellulitis is likely to be different in such settings. Two authors reviewed all abstracts identified for possible inclusion. Of studies identified initially, 5% met the selection criteria. Two reviewers extracted data independently, and data were pooled using the Freeman-Tukey transformation under a random-effects model. Our primary outcome was the summary estimate of treatment failure across intent-to-treat and clinically evaluable participants.

RESULTS

We included 19 articles reporting data from 20 studies, for a total of 3935 patients. Treatment failure was reported in 6% to 37% of participants in the 9 trials reporting intent-to-treat results, with a summary point estimate of 18% failing treatment (95% confidence interval, 15%-21%). In the 15 articles evaluating clinically evaluable participants, treatment failure rates ranged from 3% to 42%, and overall, 12% (95% confidence interval, 10%-14%) were designated treatment failures.

CONCLUSIONS

Treatment failure rates vary widely across cellulitis trials, from 6% to 37%. This may be due to confusion of cellulitis with its mimics and perhaps problems with construct validity of the diagnosis of cellulitis. Such factors bias trials toward equivalence and, in routine clinical care, impair quality and antibiotic stewardship. Objective diagnostic tools are needed.

Clostridium difficile infection following systemic antibiotic administration in randomised controlled trials: a systematic review and meta-analysis

Antibiotics have been the most important risk factor for Clostridium difficile infection (CDI). However, only data from non-randomised studies have been reviewed. We sought to evaluate the risk for development of CDI associated with the major antibiotic classes by analysing data from randomised controlled trials (RCTs). The PubMed, Cochrane and Scopus databases were searched and the references of selected RCTs were also hand-searched. Eligible studies should have compared only one antibiotic versus another administered systemically. Inclusion of studies comparing combinations of antibiotics was allowed only if the second antibiotic was the same or from the same class or if it was administered in a subset of the enrolled patients who were equally distributed in the two arms. Only a minority of the selected RCTs (79/1332; 5.9%) reported CDI episodes. Carbapenems were associated with more CDI episodes than fluoroquinolones [risk ratio (RR) = 2.44, 95% confidence interval (CI) 1.32-4.49] and cephalosporins (RR = 2.24, 95% CI 1.46-3.42), but not penicillins (RR = 2.53, 95% CI 0.87-7.41). Cephalosporins were associated with more CDIs than penicillins (RR = 2.36, 95% CI 1.32-4.23) and fluoroquinolones (RR = 2.84, 95% CI 1.60-5.06). There was no difference in CDI frequency between fluoroquinolones and penicillins (RR = 1.34, 95% CI 0.55-3.25). Finally, clindamycin was associated with more CDI episodes than cephalosporins and penicillins (RR = 3.92, 95% CI 1.15-13.43). In conclusion, data from RCTs showed that clindamycin and carbapenems were associated with more CDIs than other antibiotics.

Systemic antibiotics for treating diabetic foot infections

BACKGROUND

Foot infection is the most common cause of non-traumatic amputation in people with diabetes. Most diabetic foot infections (DFIs) require systemic antibiotic therapy and the initial choice is usually empirical. Although there are many antibiotics available, uncertainty exists about which is the best for treating DFIs.

OBJECTIVES

To determine the effects and safety of systemic antibiotics in the treatment of DFIs compared with other systemic antibiotics, topical foot care or placebo.

SEARCH METHODS

In April 2015 we searched the Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library); Ovid MEDLINE, Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE, and EBSCO CINAHL. We also searched in the Database of Abstracts of Reviews of Effects (DARE; The Cochrane Library), the Health Technology Assessment database (HTA; The Cochrane Library), the National Health Service Economic Evaluation Database (NHS-EED; The Cochrane Library), unpublished literature in OpenSIGLE and ProQuest Dissertations and on-going trials registers.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating the effects of systemic antibiotics (oral or parenteral) in people with a DFI. Primary outcomes were clinical resolution of the infection, time to its resolution, complications and adverse effects.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed the risk of bias, and extracted data. Risk ratios (RR) were estimated for dichotomous data and, when sufficient numbers of comparable trials were available, trials were pooled in a meta-analysis.

MAIN RESULTS

We included 20 trials with 3791 participants. Studies were heterogenous in study design, population, antibiotic regimens, and outcomes. We grouped the sixteen different antibiotic agents studied into six categories: 1) anti-pseudomonal penicillins (three trials); 2) broad-spectrum penicillins (one trial); 3) cephalosporins (two trials); 4) carbapenems (four trials); 5) fluoroquinolones (six trials); 6) other antibiotics (four trials).Only 9 of the 20 trials protected against detection bias with blinded outcome assessment. Only one-third of the trials provided enough information to enable a judgement about whether the randomisation sequence was adequately concealed. Eighteen out of 20 trials received funding from pharmaceutical industry-sponsors.The included studies reported the following findings for clinical resolution of infection: there is evidence from one large trial at low risk of bias that patients receiving ertapenem with or without vancomycin are more likely to have resolution of their foot infection than those receiving tigecycline (RR 0.92, 95% confidence interval (CI) 0.85 to 0.99; 955 participants). It is unclear if there is a difference in rates of clinical resolution of infection between: 1) two alternative anti-pseudomonal penicillins (one trial); 2) an anti-pseudomonal penicillin and a broad-spectrum penicillin (one trial) or a carbapenem (one trial); 3) a broad-spectrum penicillin and a second-generation cephalosporin (one trial); 4) cephalosporins and other beta-lactam antibiotics (two trials); 5) carbapenems and anti-pseudomonal penicillins or broad-spectrum penicillins (four trials); 6) fluoroquinolones and anti-pseudomonal penicillins (four trials) or broad-spectrum penicillins (two trials); 7) daptomycin and vancomycin (one trial); 8) linezolid and a combination of aminopenicillins and beta-lactamase inhibitors (one trial); and 9) clindamycin and cephalexin (one trial).Carbapenems combined with anti-pseudomonal agents produced fewer adverse effects than anti-pseudomonal penicillins (RR 0.27, 95% CI 0.09 to 0.84; 1 trial). An additional trial did not find significant differences in the rate of adverse events between a carbapenem alone and an anti-pseudomonal penicillin, but the rate of diarrhoea was lower for participants treated with a carbapenem (RR 0.58, 95% CI 0.36 to 0.93; 1 trial). Daptomycin produced fewer adverse effects than vancomycin or other semi-synthetic penicillins (RR 0.61, 95%CI 0.39 to 0.94; 1 trial). Linezolid produced more adverse effects than ampicillin-sulbactam (RR 2.66; 95% CI 1.49 to 4.73; 1 trial), as did tigecycline compared to ertapenem with or without vancomycin (RR 1.47, 95% CI 1.34 to 1.60; 1 trial). There was no evidence of a difference in safety for the other comparisons.

AUTHORS' CONCLUSIONS

The evidence for the relative effects of different systemic antibiotics for the treatment of foot infections in diabetes is very heterogeneous and generally at unclear or high risk of bias. Consequently it is not clear if any one systemic antibiotic treatment is better than others in resolving infection or in terms of safety. One non-inferiority trial suggested that ertapenem with or without vancomycin is more effective in achieving clinical resolution of infection than tigecycline. Otherwise the relative effects of different antibiotics are unclear. The quality of the evidence is low due to limitations in the design of the included trials and important differences between them in terms of the diversity of antibiotics assessed, duration of treatments, and time points at which outcomes were assessed. Any further studies in this area should have a blinded assessment of outcomes, use standardised criteria to classify severity of infection, define clear outcome measures, and establish the duration of treatment.

Tigecycline in the Treatment of Patients with Necrotizing Skin and Soft Tissue Infections Due to Multiresistant Bacteria

BACKGROUND

Necrotizing skin and soft tissue infections (NSTI) form a group of aggressive diseases that require radical debridement for infection control. Simultaneously, a high-dose broad spectrum antibiotic regimen needs to be initiated with control of septic complications in the intensive care setting. The aim of this work is to analyze the efficacy and safety of tigecycline in a subpopulation of hospitalized, severely ill surgical NSTI patients who were documented in a large multicenter non-interventional study on tigecycline use in routine clinical practice.

METHODS

A total of 1,025 patients with severe infections including complicated skin and soft-tissue infections (cSSTI, n=163; 15,9%) were enrolled in a prospective multi-center non-interventional study. Patients were to receive an initial intravenous dose of 100 mg tigecycline, followed by 50 mg twice daily. Prospectively documented parameters included clinical findings, APACHE II score, microbiological and standard laboratory assessments, surgical measures, and clinical outcomes including adverse events.

RESULTS

Of 163 patients were treated for cSSTI, with the largest subgroup being NSTI patients (n=50, 30.7% of all cSSTI, mean age 61 y, median APACHE II score 20). Forty-eight NSTI patients (96%) had at least one comorbidity. In 80% of patients, the treatment was started after previous antibiotic treatment had failed and in 34% resistant pathogens were isolated (28% methicillin resistant Staphyloccocus aureus [MRSA], 4% extended-spectrum-beta-lactamase (ESBL)-producing bacteria, and 2% vancomycin-resistant Enterococci (VRE). Tigecycline was administered as a single agent in 32 patients; 17 received combination regimens. Data from one patient were not reported. Rates of clinical cure or improvement with tigecycline treatment were 90.2%. Two patients (4%) had drug related adverse events (one thrombocytopenia and one fever/chills); 10 patients (20%) died.

CONCLUSIONS

Tigecycline alone or in combination therapy was an effective and safe antibiotic treatment in critically ill and antimicrobially pre-treated patients with NSTI frequently caused by resistant pathogens.

Novel antibiotic treatment for skin and soft tissue infection

PURPOSE OF REVIEW

Acute bacterial skin and skin structure infection (ABSSSI) is a common and significant indication for antibiotic treatment. The microbial aetiology is becoming more resistant to available antibiotics and the treatment of patients is additionally challenged by extremes of age, obesity, diabetes and other co-morbidities. This review examines recent antimicrobial developments.

RECENT FINDINGS

In many parts of the world, multidrug-resistant (MDR) staphylococci are the predominant cause of ABSSSI in both the community and in hospital. Increasing resistance in Gram-negative organisms presents problems in the management of surgical-site infections. Most new antibiotics have been developed to treat MDR Gram-positive bacteria and there are few agents to treat infections caused by MDR Gram-negative pathogens.

SUMMARY

A number of novel agents are available clinically, with other agents of related chemical structure under development. There are no entirely new classes of antibiotics. Maintaining the efficacy of antimicrobial treatment require effective antibiotic stewardship, good infection prevention and the development of further new antibiotics.

Antibiotic therapy for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) in non surgical wounds

BACKGROUND

Non surgical wounds include chronic ulcers (pressure or decubitus ulcers, venous ulcers, diabetic ulcers, ischaemic ulcers), burns and traumatic wounds. The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonisation (i.e. presence of MRSA in the absence of clinical features of infection such as redness or pus discharge) or infection in chronic ulcers varies between 7% and 30%. MRSA colonisation or infection of non surgical wounds can result in MRSA bacteraemia (infection of the blood) which is associated with a 30-day mortality of about 28% to 38% and a one-year mortality of about 55%. People with non surgical wounds colonised or infected with MRSA may be reservoirs of MRSA, so it is important to treat them, however, we do not know the optimal antibiotic regimen to use in these cases.

OBJECTIVES

To compare the benefits (such as decreased mortality and improved quality of life) and harms (such as adverse events related to antibiotic use) of all antibiotic treatments in people with non surgical wounds with established colonisation or infection caused by MRSA.

SEARCH METHODS

We searched the following databases: The Cochrane Wounds Group Specialised Register (searched 13 March 2013); The Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2); Database of Abstracts of Reviews of Effects (2013, Issue 2); NHS Economic Evaluation Database (2013, Issue 2); Ovid MEDLINE (1946 to February Week 4 2013); Ovid MEDLINE (In-Process & Other Non-Indexed Citations, March 12, 2013); Ovid EMBASE (1974 to 2013 Week 10); EBSCO CINAHL (1982 to 8 March 2013).

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) comparing antibiotic treatment with no antibiotic treatment or with another antibiotic regimen for the treatment of MRSA-infected non surgical wounds. We included all relevant RCTs in the analysis, irrespective of language, publication status, publication year, or sample size.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified the trials, and extracted data from the trial reports. We calculated the risk ratio (RR) with 95% confidence intervals (CI) for comparing the binary outcomes between the groups and planned to calculate the mean difference (MD) with 95% CI for comparing the continuous outcomes. We planned to perform the meta-analysis using both fixed-effect and random-effects models. We performed intention-to-treat analysis whenever possible.

MAIN RESULTS

We identified three trials that met the inclusion criteria for this review. In these, a total of 47 people with MRSA-positive diabetic foot infections were randomised to six different antibiotic regimens. While these trials included 925 people with multiple pathogens, they reported the information on outcomes for people with MRSA infections separately (MRSA prevalence: 5.1%). The only outcome reported for people with MRSA infection in these trials was the eradication of MRSA. The three trials did not report the review's primary outcomes (death and quality of life) and secondary outcomes (length of hospital stay, use of healthcare resources and time to complete wound healing). Two trials reported serious adverse events in people with infection due to any type of bacteria (i.e. not just MRSA infections), so the proportion of patients with serious adverse events was not available for MRSA-infected wounds. Overall, MRSA was eradicated in 31/47 (66%) of the people included in the three trials, but there were no significant differences in the proportion of people in whom MRSA was eradicated in any of the comparisons, as shown below.1. Daptomycin compared with vancomycin or semisynthetic penicillin: RR of MRSA eradication 1.13; 95% CI 0.56 to 2.25 (14 people).2. Ertapenem compared with piperacillin/tazobactam: RR of MRSA eradication 0.71; 95% CI 0.06 to 9.10 (10 people).3. Moxifloxacin compared with piperacillin/tazobactam followed by amoxycillin/clavulanate: RR of MRSA eradication 0.87; 95% CI 0.56 to 1.36 (23 people).

AUTHORS' CONCLUSIONS

We found no trials comparing the use of antibiotics with no antibiotic for treating MRSA-colonised non-surgical wounds and therefore can draw no conclusions for this population. In the trials that compared different antibiotics for treating MRSA-infected non surgical wounds, there was no evidence that any one antibiotic was better than the others. Further well-designed RCTs are necessary.

Gender analysis of moxifloxacin clinical trials

PURPOSE

To determine the inclusion of women and the sex-stratification of results in moxifloxacin Clinical Trials (CTs), and to establish whether these CTs considered issues that specifically affect women, such as pregnancy and use of hormonal therapies. Previous publications about women's inclusion in CTs have not specifically studied therapeutic drugs. Although this type of drug is taken by men and women at a similar rate, adverse effects occur more frequently in the latter.

METHODS

We reviewed 158 published moxifloxacin trials on humans, retrieved from MedLine and the Cochrane Library (1998-2010), to determine whether they complied with the gender recommendations published by U.S. Food and Drug Administration Guideline.

RESULTS

Of a total of 80,417 subjects included in the moxifloxacin CTs, only 33.7% were women in phase I, in contrast to phase II, where women accounted for 45%, phase III, where they represented 38.3% and phase IV, where 51.3% were women. About 40.9% (n=52) of trials were stratified by sex and 15.3% (n=13) and 9% (n=7) provided data by sex on efficacy and adverse effects, respectively. We found little information about the influence of issues that specifically affect women. Only 3 of the 59 journals that published the moxifloxacin CTs stated that authors should stratify their results by sex.

CONCLUSIONS

Women are under-represented in the published moxifloxacin trials, and this trend is more marked in phase I, as they comprise a higher proportion in the other phases. Data by sex on efficacy and adverse effects are scarce in moxifloxacin trials. These facts, together with the lack of data on women-specific issues, suggest that the therapeutic drug moxifloxacin is only a partially evidence-based medicine.

Sequential intravenous/oral moxifloxacin monotherapy for complicated skin and skin structure infections: a meta-analysis of randomised controlled trials

OBJECTIVES

The presumed superiority of moxifloxacin for the treatment of complicated skin and skin structure infections (cSSSIs) is based on laboratory data, but has not yet been established on clinical grounds. The aim of this meta-analysis was to evaluate the efficacy and safety of sequential intravenous (i.v.)/oral (p.o.) moxifloxacin monotherapy for the treatment of cSSSIs.

METHODS

Randomised controlled trials (RCTs) published prior to November 2012 were systematically retrieved from PubMed, MEDLINE, EMBASE, ScienceDirect, ClinicalTrials.gov and the Cochrane Central Register of Controlled Trials. Finally, a meta-analysis of all RCTs eligible for inclusion criteria was performed.

RESULTS

Three studies that enrolled 2255 patients were included in the meta-analysis. There were no statistically significant differences between patients given moxifloxacin and those given other antibiotics with regard to clinical success rate [1667 patients, odds ratio (OR) = 0.83, 95% confidence interval (CI) 0.63 to 1.09, p = 0.18], bacteriological success rate (bacteriological success rates: 1502 patients, OR = 0.90, 95% CI 0.68-1.18, p = 0.45) or mortality (2207 patients, OR = 1.96, 95% CI 0.79-4.88, p = 0.15). Significantly, more overall adverse events (AEs) were associated with the use of moxifloxacin than with other antibiotics (2207 patients, OR = 1.21, 95%CI 1.00-1.45, p = 0.04). However, there was no statistically significant difference in the occurrence of drug-related AEs, serious AEs or serious drug-related AEs between patients given moxifloxacin and those given other antibiotics.

CONCLUSION

Sequential i.v./p.o. moxifloxacin monotherapy is an effective and relatively safe option for the treatment of cSSSIs. Other benefits of moxifloxacin may make it a more viable option compared with the currently used regimens.

Moxifloxacin in complicated skin and skin structure infections (cSSSIs): A prospective, international, non-interventional, observational study

Introduction

ARTOS was an international, prospective, non-interventional, non-controlled observational study designed to determine the effectiveness, safety, and tolerability of moxifloxacin under daily-life conditions in patients with complicated skin and skin structure infections (cSSSIs) treated in Europe, the Middle East, and Asia–Pacific region.

Methods

Eligible patients included males and females who were hospitalized patients or outpatients requiring antibiotic therapy for cSSSIs and for whom the treating physician had elected to begin moxifloxacin therapy in accordance with its approved indications. Patients were assessed before therapy and then at one or two follow-up visits. Effectiveness was assessed with respect to improvement and resolution of signs and symptoms of cSSSIs and safety with respect to the nature and frequency of adverse events and adverse drug reactions.

Results

A total of 6,594 patients were enrolled of whom 5,444 had data available for analysis; 4,692 patients received sequential intravenous/oral (IV/PO) moxifloxacin and 752 exclusively IV therapy. A majority of patients were aged between 40 and 79 years and had one or more comorbid conditions. Post-surgical wound infection, skin abscess, and diabetic foot infection were the cSSSIs most frequently diagnosed and treated with moxifloxacin, with almost 90% of infections rated moderate or severe. Treating physicians chose sequential moxifloxacin 400 mg for most patients, switching from IV to PO after 3–4 days. On average, treatment was maintained for 10 days. Treatment with moxifloxacin was associated with rapid relief in symptoms, with 93.2% of patients experiencing either complete resolution of symptoms or improvement at follow-up. Moxifloxacin was well tolerated with adverse drug reactions occurring in only 2% of patients.

Conclusions

This study, conducted in a ‘real-world’ setting, confirms the effectiveness and safety of moxifloxacin in the treatment of a wide spectrum of cSSSIs seen in routine clinical practice.

Efficacy and safety of IV/PO moxifloxacin and IV piperacillin/tazobactam followed by PO amoxicillin/clavulanic acid in the treatment of diabetic foot infections: results of the RELIEF study

OBJECTIVE

The aim was to compare the efficacy and safety of two antibiotic regimens in patients with diabetic foot infections (DFIs).

METHODS

Data of a subset of patients enrolled in the RELIEF trial with DFIs requiring surgery and antibiotics were evaluated retrospectively. DFI was diagnosed on the basis of the modified Wagner, University of Texas, and PEDIS classification systems. Patients were randomized to receive either intravenous/oral moxifloxacin (MXF, N = 110) 400 mg q.d. or intravenous piperacillin/tazobactam 4.0/0.5 g t.d.s. followed by oral amoxicillin/clavulanate 875/125 mg b.d. (PIP/TAZ-AMC, N = 96), for 7-21 days until the end of treatment (EOT). The primary endpoint was clinical cure rates in the per-protocol (PP) population at the test-of-cure visit (TOC, 14-28 days after EOT).

RESULTS

There were no significant differences between the demographic characteristics of PP patients in either treatment group. At TOC, MXF and PIP/TAZ-AMC had similar efficacy in both the PP and intent-to-treat (ITT) populations: MXF: 76.4 % versus PIP/TAZ-AMC: 78.1 %; 95 % confidence interval (CI) -14.5 %, 9.0 % in the PP population; MXF: 69.9 % versus PIP/TAZ-AMC: 69.1 %; 95 % CI -12.4 %, 12.1 % in the ITT population. The overall bacteriological success rates were similar in both treatment groups (MXF: 71.7 % versus PIP/TAZ-AMC: 71.8 %; 95 % CI -16.9 %, 10.7 %). A similar proportion of patients (ITT population) experienced any adverse events in both treatment groups (MXF: 30.9 % versus PIP/TAZ-AMC: 31.8 %, respectively). Death occurred in three MXF-treated patients and one PIP/TAZ-AMC-treated patient; these were unrelated to the study drugs.

CONCLUSION

Moxifloxacin has shown favorable safety and efficacy profiles in DFI patients and could be an alternative antibiotic therapy in the management of DFI.

CLINICAL TRIAL

NCT00402727.

A randomized trial of the efficacy and safety of sequential intravenous/oral moxifloxacin monotherapy versus intravenous piperacillin/tazobactam followed by oral amoxicillin/clavulanate for complicated skin and skin structure infections

OBJECTIVES

The primary aim of the RELIEF study was to evaluate the efficacy and safety of two sequential intravenous (iv)/oral regimens: moxifloxacin iv/oral versus piperacillin/tazobactam (TZP) iv followed by oral amoxicillin/clavulanate (AMC).

PATIENTS AND METHODS

The study had a prospective, randomized, double-dummy, double-blind, multicentre design. Patients ≥18 years were prospectively stratified according to complicated skin and skin structure infection (cSSSI) subtype/diagnosis (major abscess, diabetic foot infection, wound infection or infected ischaemic ulcer), surgical intervention and severity of illness. Diagnoses and disease severity were based on predetermined criteria, documented by repeated photographs, and confirmed by an independent data review committee. Patients were randomized to receive either 400 mg of moxifloxacin iv once daily followed by 400 mg of moxifloxacin orally once daily or 4.0/0.5 g of TZP iv thrice daily followed by 875/125 mg of AMC orally twice daily for 7-21 days. The primary efficacy variable was clinical response at test of cure (TOC) for the per-protocol (PP) population. Clinical efficacy was assessed by the data review committee based on repeated photographs and case descriptions. Clinical trials registry number: NCT 00402727.

RESULTS

A total of 813 patients were randomized. Clinical success rates at TOC were similar for moxifloxacin and TZP-AMC in the PP [320/361 (88.6%) versus 275/307 (89.6%), respectively; P = 0.758] and intent-to-treat (ITT) [350/426 (82.2%) versus 305/377 (80.9%), respectively; P = 0.632] populations. Thus, moxifloxacin was non-inferior to TZP-AMC. Bacteriological success rates were high in both treatment arms [moxifloxacin: 432/497 (86.9%) versus TZP-AMC: 370/429 (86.2%), microbiologically valid (MBV) population]. Moxifloxacin was non-inferior to TZP-AMC at TOC in both the MBV and the ITT populations. Both treatments were well tolerated.

CONCLUSIONS

Once-daily iv/oral moxifloxacin monotherapy was clinically and bacteriologically non-inferior to iv TZP thrice daily followed by oral AMC twice daily in patients with cSSSIs.

Moxifloxacin in the treatment of skin and skin structure infections

Moxifloxacin is a recent addition to the fluoroquinolone class, differing from ciprofloxacin and other older agents in having much better in vitro activity against Gram-positive aerobes while retaining potent activity against Gram-negative aerobes. It is also active against the pathogens of human and animal bite wounds and those species of atypical mycobacteria associated with dermatologic infections. Its activity against anaerobes is quite variable. Moxifloxacin penetrates well into inflammatory blister fluid and muscle and subcutaneous adipose tissues. Moxifloxacin should thus be a reasonable option for the treatment of skin and skin structure infections (SSSIs). In 3 randomized controlled trials (RCTs), oral moxifloxacin was as effective as cephalexin in the treatment of uncomplicated SSSIs in adults while in 2 RCTs, intravenous/oral moxifloxacin was as effective as intravenous/oral β-lactam/β-lactamase inhibitor therapy in the treatment of complicated SSSIs in adults. Moxifloxacin does not inhibit cytochrome P450 enzymes and thus interact with warfarin or methylxanthines. However, multivalent cations can reduce its oral bioavailability substantially. Dosage adjustment is not required in the presence of renal or hepatic impairment. The clinical relevance of its electrophysiologic effects (QT_c prolongation) remains unresolved.

[Empirical antibiotic therapy of complicated skin and soft tissue infections in dermatological practice]

Erysipelas is an acute bacterial infection of the skin predominantly caused by Streptococcus pyogenes. According to the international classification complicated erysipelas belongs to the complicated skin and soft tissue infections. Complicated infections are defined as severe skin involvement or when the infection occurs in compromised hosts. These infections frequently involve Gram-negative bacilli and anaerobic bacteria.

AIMS

The aim of this study was to compare the efficacy of the empirical antibiotic therapy for the patients who were admitted to the Department of Dermatology and Allergology, University of Szeged.

METHODS

The empirical therapy was started according to a previously determined protocol. The data of 158 patients with complicated skin and soft tissue infections were analyzed and the microbiology culture specimens and the isolates were also examined.

RESULTS AND CONCLUSIONS

The results show that penicillin is the first choice for the treatment of erysipelas. However, the complicated skin and soft tissue infections require broad-spectrum antibiotics.

Efficacy of topically delivered moxifloxacin against wound infection by Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus

Wound infection is a common risk for patients with chronic nonhealing wounds, causing high morbidity and mortality. Currently, systemic antibiotic treatment is the therapy of choice, despite often leading to several side effects and the risk of an insufficient tissue penetration due to impaired blood supply. If systemically delivered, moxifloxacin penetrates well into inflammatory blister fluid, muscle, and subcutaneous adipose tissues and might therefore be a possible option for the topical treatment of skin and infected skin wounds. In this study, topical application of moxifloxacin was investigated in comparison to mupirocin, linezolid, and gentamicin using a porcine wound infection and a rat burn infection model. Both animal models were performed either by an inoculation with methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa. Wound fluid, tissue, and blood samples were taken, and bacterial counts as well as the moxifloxacin concentration were determined for a 14-day follow-up. A histological comparison of the rat burn wound tissues was performed. Both strains were susceptible to moxifloxacin and gentamicin, whereas mupirocin and linezolid were effective only against MRSA. All antibiotics showed efficient reduction of bacterial counts, and except with MRSA, infected burn wounds reached bacterial counts below 10(5) CFU/g tissue. Additionally, moxifloxacin was observed to promote wound healing as determined by histologic analysis, while no induction of bacterial resistance was observed during the treatment period. The use of topical antibiotics for the treatment of infected wounds confers many benefits. Moxifloxacin is therefore an ideal candidate, due to its broad antibacterial spectrum, its high efficiency, and its potential to promote wound healing.

Complicated skin and soft tissue infection

Skin and soft tissue infections (SSTIs) are common, and complicated SSTIs (cSSTIs) are the more extreme end of this clinical spectrum, encompassing a range of clinical presentations such as deep-seated infection, a requirement for surgical intervention, the presence of systemic signs of sepsis, the presence of complicating co-morbidities, accompanying neutropenia, accompanying ischaemia, tissue necrosis, burns and bites. Staphylococcus aureus is the commonest cause of SSTI across all continents, although its epidemiology in terms of causative strains and antibiotic susceptibility can no longer be predicted with accuracy. The epidemiology of community-acquired and healthcare-acquired strains is constantly shifting and this presents challenges in the choice of empirical antibiotic therapy. Toxin production, particularly with Panton-Valentine leucocidin, may complicate the presentation still further. Polymicrobial infection with Gram-positive and Gram-negative organisms and anaerobes may occur in infections approximating the rectum or genital tract and in diabetic foot infections and burns. Successful management of cSSTI involves prompt recognition, timely surgical debridement or drainage, resuscitation if required and appropriate antibiotic therapy. The mainstays of treatment are the penicillins, cephalosporins, clindamycin and co-trimoxazole. β-Lactam/β-lactamase inhibitor combinations are indicated for polymicrobial infection. A range of new agents for the treatment of methicillin-resistant S. aureus infections have compared favourably with the glycopeptides and some have distinct pharmacokinetic advantages. These include linezolid, daptomycin and tigecycline. The latter and fluoroquinolones with enhanced anti-Gram-positive activity such as moxifloxacin are better suited for polymicrobial infection.

Treatment of complicated skin and soft-tissue infections caused by resistant bacteria: value of linezolid, tigecycline, daptomycin and vancomycin

Antibiotic-resistant organisms causing both hospital- and community-acquired complicated skin and soft-tissue infections (cSSTI) are increasingly reported. A substantial medical and economical burden associated with MRSA colonisation or infection has been documented. The number of currently available appropriate antimicrobial agents is limited. Good quality randomised, controlled clinical trial data on antibiotic efficacy and safety is available for cSSTI caused by MRSA. Linezolid, tigecycline, daptomycin and vancomycin showed efficacy and safety in MRSA-caused cSSTI. None of these drugs showed significant superiority in terms of clinical cure and eradication rates.To date, linezolid offers by far the greatest number of patients included in controlled trials with a strong tendency of superiority over vancomycin in terms of eradication and clinical success.. - Tigecycline is an alternative in polymicrobial infections except by diabetic foot infections. Daptomycin might be a treatment option for cases of cSSTI with MRSA bacteremia. cSSTI caused by resistant Gram-negative bacteria are a matter of great concern. The development of new antibiotics in this area is an urgent priority to avoid the risk of a postantibiotic era with no antimicrobial treatment options. An individual approach for every single patient is mandatory to evaluate the optimal antimicrobial treatment regimen.

Moxifloxacin: update and perspectives after 8 years of usage

Moxifloxacin has a broad spectrum of activity, including Gram-positive and Gram-negative organisms, atypical respiratory pathogens, anaerobes and penicillin- and macrolide-resistant Streptococcus pneumoniae. It achieves good tissue penetration and high concentrations in clinically relevant tissues and fluids. It is available in both an oral and intravenous formulation, has a once-daily administration and a good tolerance and safety profile. Moxifloxacin is used mainly for the treatment of acute bacterial exacerbation of chronic bronchitis, community-acquired pneumonia, acute bacterial sinusitis, complicated skin and skin-structure infections and complicated intra-abdominal infections, as well as pulmonary TB, although it is not approved in this indication. The most recent studies covering these clinical indications are discussed.

Interventions for cellulitis and erysipelas

BACKGROUND

Cellulitis and erysipelas are now usually considered manifestations of the same condition, a skin infection associated with severe pain and systemic symptoms. A range of antibiotic treatments are suggested in guidelines.

OBJECTIVES

To assess the efficacy and safety of interventions for non-surgically-acquired cellulitis.

SEARCH STRATEGY

In May 2010 we searched for randomised controlled trials in the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials in The Cochrane Library, MEDLINE, EMBASE, and the ongoing trials databases.

SELECTION CRITERIA

We selected randomised controlled trials comparing two or more different interventions for cellulitis.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data.

MAIN RESULTS

We included 25 studies with a total of 2488 participants. Our primary outcome 'symptoms rated by participant or medical practitioner or proportion symptom-free' was commonly reported. No two trials examined the same drugs, therefore we grouped similar types of drugs together.Macrolides/streptogramins were found to be more effective than penicillin antibiotics (Risk ratio (RR) 0.84, 95% CI 0.73 to 0.97). In 3 trials involving 419 people, 2 of these studies used oral macrolide against intravenous (iv) penicillin demonstrating that oral therapies can be more effective than iv therapies (RR 0.85, 95% CI 0.73 to 0.98).Three studies with a total of 88 people comparing a penicillin with a cephalosporin showed no difference in treatment effect (RR 0.99, 95% CI 0.68 to 1.43).Six trials which included 538 people that compared different generations of cephalosporin, showed no difference in treatment effect (RR 1.00, 95% CI 0.94 to1.06).We found only small single studies for duration of antibiotic treatment, intramuscular versus intravenous route, the addition of corticosteroid to antibiotic treatment compared with antibiotic alone, and vibration therapy, so there was insufficient evidence to form conclusions. Only two studies investigated treatments for severe cellulitis and these selected different antibiotics for their comparisons, so we cannot make firm conclusions.

AUTHORS' CONCLUSIONS

We cannot define the best treatment for cellulitis and most recommendations are made on single trials. There is a need for trials to evaluate the efficacy of oral antibiotics against intravenous antibiotics in the community setting as there are service implications for cost and comfort.

Moxifloxacin distribution in the interstitial space of infected decubitus ulcer tissue of patients with spinal cord injury measured by in vivo microdialysis

We investigated the distribution of moxifloxacin in the interstitial space of normal and infected subcutaneous tissue in patients with spinal cord injury and decubitus ulcers using in vivo microdialysis. Drug concentrations achieved in serum, saliva, normal and infected tissues showed approximately parallel time profiles. The interstitial tissue fluids reached bactericidal levels for common bacteria found in infected skin lesions. Our findings suggest that moxifloxacin exhibits good and similar penetration into the interstitial space fluid in normal subcutaneous tissue and infected decubitus ulcers in patients with spinal cord injury.

Factors associated with treatment failure in patients with diabetic foot infections: An analysis of data from randomized controlled trials

BACKGROUND

Although several antibiotics have been studied for the treatment of foot infections, their effectiveness has been considered to be similar. The scope of this analysis was the identification of factors that are associated with treatment failure based on evidence from randomized controlled trials (RCTs).

METHODS

Two reviewers independently extracted data from published RCTs comparing different antibiotics for diabetic foot infections (DFIs).

RESULTS

The combined observed treatment failure was 22.7% in the 18 RCTs included in the analysis. When different regimens of various antibiotics (penicillins, carbapenems, cephalosporins, and fluoroquinolones) were directly compared in the individual RCTs, they were associated with similar frequency of treatment failure. However, when all patients were combined, carbapenems were associated with fewer treatment failures. Also, treatment failure in patients with DFIs from whom methicillin-resistant S. aureus (MRSA) alone or as part of a polymicrobial infection was isolated was more common than in patients from whom other bacteria were isolated [24/68 (35.3%) versus 350/1522 (23%), p=0.02]. Among patients with DFIs due to MRSA the use of linezolid was not associated with better effectiveness in comparison to other antibiotics [treatment failure: 6/19 (31.6%) versus 18/49 (36.7%), p=0.69]. Of interest, treatment failure was similar in patients with and without osteomyelitis [44/169 (26.5%) versus 330/1424 (23.2%), p=0.34].

CONCLUSIONS

The isolation of MRSA seems to be a significant factor associated with treatment failure in patients with DFIs. Further research efforts are needed for the identification of additional risk factors for treatment failure and optimization of the management of patients with DFIs.

New drugs to treat skin and soft tissue infections

Due to increasing antimicrobial resistance, a pressing need exists for new antibiotics to treat skin and soft tissue infections. Several newer agents such as tigecycline, daptomycin, and linezolid have been important additions for the treatment of multidrug-resistant pathogens. New drugs in development such as dalbavancin and ceftobiprole will further enhance our ability to treat mixed infections and improve patient compliance. These promising new antimicrobials will likely grow in importance as resistant bacterial strains increase in community-acquired infections.

Piperacillin-tazobactam: a beta-lactam/beta-lactamase inhibitor combination

Piperacillin-tazobactam is a beta-lactam/beta-lactamase inhibitor combination with a broad spectrum of antibacterial activity that includes Gram-positive and -negative aerobic and anaerobic bacteria. Piperacillin-tazobactam retains its in vitro activity against broad-spectrum beta-lactamase-producing and some extended-spectrum beta-lactamase-producing Enterobacteriaceae, but not against isolates of Gram-negative bacilli harboring AmpC beta-lactamases. Piperacillin-tazobactam has recently been reformulated to include ethylenediaminetetraacetic acid and sodium citrate; this new formulation has been shown to be compatible in vitro with the two aminoglycosides, gentamicin and amikacin, allowing for simultaneous Y-site infusion, but not with tobramycin. Multicenter, randomized, double-blinded clinical trials have demonstrated piperacillin-tazobactam to be as clinically effective as relevant comparator antibiotics. Clinical trials have demonstrated piperacillin-tazobactam to be effective for the treatment of patients with intra-abdominal infections, skin and soft tissue infections, lower respiratory tract infections, complicated urinary tract infections, gynecological infections and more recently, febrile neutropenia. Piperacillin-tazobactam has an excellent safety and tolerability profile and continues to be a reliable option for the empiric treatment of moderate-to-severe infections in hospitalized patients.

Treating diabetic foot infections with sequential intravenous to oral moxifloxacin compared with piperacillin–tazobactam/amoxicillin–clavulanate

OBJECTIVES

Complicated skin and skin structure infections (cSSSIs), including diabetic foot infections (DFIs), are often polymicrobial, requiring combination or broad-spectrum therapy. Moxifloxacin, a broad-spectrum fluoroquinolone, is approved for cSSSI and can be administered by either intravenous (iv) or oral routes. To assess the efficacy of moxifloxacin for treating DFIs, we analysed a subset of patients with these infections who were enrolled in a prospective, double-blind study that compared the efficacy of moxifloxacin with piperacillin-tazobactam and amoxicillin-clavulanate.

METHODS

Patients>or=18 years of age with a DFI requiring initial iv therapy were randomized to either moxifloxacin (400 mg/day) or piperacillin-tazobactam (3.0/0.375 g every 6 h) for at least 3 days followed by moxifloxacin (400 mg/day orally) or amoxicillin-clavulanate (800 mg every 12 h orally), if appropriate, for 7-14 days. DFI was usually defined as any foot infection plus a history of diabetes. Our primary efficacy outcome was the clinical response of the infection at test-of-cure (TOC), 10-42 days post-therapy.

RESULTS

Among 617 patients enrolled in the original study, 78 with DFIs were evaluable for treatment efficacy. Clinical cure rates at TOC were similar for moxifloxacin and piperacillin-tazobactam/amoxicillin-clavulanate (68% versus 61%) for patients with investigator-defined infection (P=0.54). Overall pathogen eradication rates in the microbiologically-valid population were 69% versus 66% for moxifloxacin and comparator, respectively (P=1.00).

CONCLUSIONS

Intravenous+/-oral moxifloxacin was as effective as iv piperacillin-tazobactam+/-amoxicillin-clavulanate in treating moderate-to-severe DFIs. Moxifloxacin may have potential as a monotherapy regimen for DFIs.

Skin and skin structure infections: treatment with newer generation fluoroquinolones

Skin and skin structure infections (SSSI) are an emerging issue in healthcare. They are responsible for increasing heathcare utilization, both in hospitalizations and intravenous antibiotic use. SSSI are caused by an evolving variety of pathogens, including Gram-positive, Gram-negative, and anaerobic bacteria. In combination with mounting resistance patterns, this diverse range of bacteria mandate empiric broad-spectrum antibiotic coverage. Historically, cephalosporins and penicillins have been the mainstay of treatment, but recent data suggest newer generation fluoroquinolones are being used with increasing frequency. In 2005, moxifloxacin joined gatifloxacin and levofloxacin as newer generation fluoroquionolones with Food and Drug Administration indications for SSSIs. Even within this group there exist subtle differences that impact optimal management. This paper offers the clinician a comparative review of the antimicrobial spectrum, pharmacodynamics, pharmacokinetics, and clinical efficacy data to support the appropriate use of fluoroquinolones in SSSIs.

An infectious disease update on antibiotics: emerging resistance

Podiatric physicians often encounter infectious processes in the lower extremity in inpatient and outpatient settings. Bacterial resistance to antibiotics is a growing concern for clinicians treating these infections, especially in complex patients who have immune compromise such as diabetes. Although a number of antibiotic options are available for the treatment of lower-extremity soft tissue and bone infections, a careful examination of bacterial susceptibilities, drug resistance, and treatment efficacy can result in better patient care and limb salvage.

An improved high-performance liquid chromatographic method with a solid-phase extraction for the determination of piperacillin and tazobactam: application to pharmacokinetic study of different dosage in Chinese healthy volunteers

An improved HPLC method was developed for the determination of piperacillin and tazobactam in human plasma and pharmacokinetic study in Chinese healthy volunteers. Piperacillin and tazobactam in human plasma were extracted by solid-phase extraction and separated on a C(18) column and detected at 220 nm. The mobile phase for piepracillin consisted of 0.01 mol/L sodium dihydrogen phosphate (pH = 4.65) and acetonitrile (71:29, v/v), and that for tazobactam was 0.05 mol/L sodium dihydrogen phosphate (pH = 4.45) and methanol (90:10, v/v). The method was linear in the range 0.25-320.00 microg/mL for piperacillin (r(2) = 0.995) and 0.25-64.00 microg/mL for tazobactam (r(2) = 0.994). The lower limit of quantification of both compounds was 0.25 microg/mL. The intra- and inter-day precisions of piperacillin and tazobactam at three concentrations were all less than 9.2% and accuracies were within the range 97.0-108.0%. The method was used to investigate the pharmacokinetics of piperacillin and tazobactam in 12 volunteers who were intravenously given a dosage of 1.25, 2.50 and 3.75 g in three periods. The results showed that piperacillin sodium-tazobactom sodium (4:1) for injection in Chinese people fits linear dynamics, and the administred dosage can be adjusted with therapeutic effect.

Fluoroquinolones vs beta-lactams for empirical treatment of immunocompetent patients with skin and soft tissue infections: a meta-analysis of randomized controlled trials

OBJECTIVE

To compare the effectiveness and safety of fluoroquinolones with beta-lactams in the treatment of patients with skin and soft tissue infections (SSTIs).

METHODS

We searched the PubMed database, Cochrane Database of Controlled Trials, and references of relevant articles for study reports published between January 1980 and February 2006.

RESULTS

Twenty randomized controlled trials that enrolled 4817 patients were included in the analysis. Fluoroquinolones as empirical treatment of patients with SSTIs were more effective than beta-lactams for the clinically evaluable patients (90.4% vs 88.2%; odds ratio [OR], 1.29; 95% confidence interval [CI], 1.00-1.66). This was also true in subset analyses of randomized controlled trials that studied ciprofloxacin (OR, 2.49; 95% CI, 1.45-4.26) and for patients with mild to moderate infections (OR, 1.83; 95% CI, 1.13-2.96). In contrast, no difference was found between the compared regimens for patients with moderate to severe infections (OR, 1.12; 95% CI, 0.80-1.55), for patients who did not receive third-generation cephalosporins as the comparator antibiotic (OR, 0.99; 95% CI, 0.73-1.34), or for the microbiologically evaluable patients (OR, 1.19; 95% CI, 0.89-1.59). Fluoroquinolones were also associated with more adverse effects (19.2% vs 15.2%; OR, 1.33; 95% CI, 1.13-1.57).

CONCLUSION

The high proportion of successfully treated patients in the compared groups of antibiotics and the development of more adverse effects associated with fluoroquinolone use suggest that these antibiotics do not have substantial advantages compared with beta-lactams for empirical treatment of patients with SSTIs.

Fluoroquinolones and Anaerobes

The usefulness of fluoroquinolones for the treatment of mixed aerobic and anaerobic infections has been investigated since these agents started being used in clinical practice. Newer compounds have increased in vitro activity against anaerobes, but clinically relevant susceptibility breakpoints for these bacteria have not been established. Pharmacodynamic analyses and corroboration by new data from clinical trials have enhanced our knowledge concerning the use of fluoroquinolones to treat selective anaerobic pathogens. These studies suggest that newer agents could be useful in the treatment of several types of mixed aerobic and anaerobic infections, including skin and soft-tissue, intra-abdominal, and respiratory infections. The major concerns with expanding the use of fluoroquinolones to treat anaerobic infections have been reports of increasing resistance in Bacteroides group isolates and the impact of these antibiotics on the incidence of Clostridium difficile-associated disease.