Randomized comparison trial of teicoplanin i.v., teicoplanin i.m., and cefazolin therapy for skin and soft tissue infections caused by gram-positive bacteria

Native valve right sided infective endocarditis

Right-sided infective endocarditis (RSIE) accounts for 5-10% of all cases of infective endocarditis (IE), and is predominantly encountered in the injecting drug user (IDU) population, where HIV and HCV coinfections often coexist. Staphylococcus aureus is the most common pathogen. The pathogenesis of RSIE is still not well understood. RSIE usually presents as a persistent fever with respiratory symptoms whilst signs of systemic embolisation as seen in left-sided IE are notably absent. The prompt diagnosis of RSIE thus requires a high index of suspicion. Transthoracic echocardiography (TTE) can detect the majority of RSIE, whilst transoesophageal echocardiography (TOE) can increase sensitivity. Virulence of the causative organism and vegetation size are the major determinants of prognosis. Most cases of RSIE resolve with appropriate antibiotic administration.

Comparative effectiveness of antibiotics for the treatment of MRSA complicated skin and soft tissue infections

OBJECTIVE

With a growing number of studies and comparators in MRSA skin infections, a unified framework for comparing treatments is needed for health technology assessment (HTA). The objective was to systematically assess the success rates of common antimicrobial agents for the treatment of complicated skin and soft tissue infections (cSSTIs) caused by MRSA.

METHODS

MEDLINE, EMBASE, and Cochrane databases were searched to identify published clinical trials in which dalbavancin, daptomycin, linezolid, telavancin, teicoplanin, tigecycline, and vancomycin were used to treat cSSTIs. Pooled efficacy estimates were generated from clinical and microbiological determinations of success for the MRSA-subgroups in cSSTI clinical trials using a Bayesian meta-analytic approach. Success rates for each antibiotic were reported with 95% Bayesian confidence intervals (called credible intervals [CrI]). In sensitivity analyses the impact of different model parameters and article quality were investigated.

RESULTS

Out of 36 identified studies, 14 studies on six antibiotics with 28 treatment arms (n = 1840) were included in the analysis. No MRSA data in cSSTI were found for teicoplanin. The pooled success rate and CrI(95%) for each agent was: vancomycin (74.7%; CrI(95%): 64.1%-83.5%), dalbavancin (87.7%; CrI(95%): 74.6%-95.4%), linezolid (84.4%; CrI(95%): 76.6%-90.6%), telavancin (83.5%; CrI(95%): 73.6%-90.8%), daptomycin (78.1%; CrI(95%): 54.6%-93.2%) and tigecycline (70.4%; CrI(95%): 48.0%-87.6%). Comparisons between antibiotics suggested differences versus vancomycin for linezolid (+9.7%; CrI(95%): 4.4%-15.8%), dalbavancin (+13.1%; CrI(95%): 1.0%-23.8%), and telavancin (+8.8%; CrI(95%): 1.5-16.7%). The finding of lower vancomycin efficacy in MRSA cSSTI did not change in sensitivity analyses.

CONCLUSION

The results of this meta-analysis suggest higher success rates for linezolid and the new glycopeptides (dalbavancin and telavancin) in MRSA-confirmed cSSTIs. The uncertainty margins reflect the study limitations including number of cases and indirect nature of the comparisons. This example of Bayesian meta-analysis for MRSA cSSTI provides a potential framework for comparisons that is useful for HTA and formulary decision-making.

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.

Daptomycin Versus Other Antimicrobial Agents for the Treatment of Skin and Soft Tissue Infections: A Meta-Analysis

BACKGROUND

Skin and soft tissue infections (SSTIs) are common in everyday clinical practice. Daptomycin has been shown to achieve very good concentrations in skin and soft tissues.

OBJECTIVE

To compare the effectiveness and toxicity of daptomycin with that of other antimicrobials for the treatment of SSTIs.

METHODS

PubMed, Scopus, and the Cochrane Central Register of Controlled Trials were searched for articles published up to March 2009. Comparative studies in which daptomycin was used in the intervention group were included in this meta-analysis. The primary outcome of interest was clinical success; secondary outcomes were microbiologic success, clinical success in subsets with complicated SSTIs (cSSTIs) or infections due to methicillin-resistant Staphylococcus aureus; (MRSA), clinical success of daptomycin-versus vancomycin-treated patients, time to clinical cure, treatment-related adverse events, withdrawal from treatment due to toxicity, all-cause mortality, and development of resistance.

RESULTS

Four studies were included in the analysis (3 were randomized controlled trials [RCTs]). Vancomycin and semisynthetic penicillins were used in the comparator arm. Three studies reported on patients with cSSTIs. The intention-to-treat (ITT) population was 1557 patients. No statistically significant difference between daptomycin and comparators was found regarding clinical success in clinically evaluable (OR 0.89; 95% CI 0.63 to 1.25 in the 3 RCTs and OR 1.34; 95% CI 0.38 to 4.66 with all 4 studies included), ITT, MRSA-infected patients, and those with cSSTIs. Two studies reported that significantly fewer patients with cSSTIs required prolonged treatment in the daptomycin arm and that clinical cure was faster than with comparators. No difference between the compared regimens was found in other outcomes.

CONCLUSIONS

Daptomycin is effective and safe for the treatment of SSTIs. Studies evaluating the optimal duration of daptomycin therapy for cSSTIs, comparing daptomycin with new agents, and focusing on proven MRSA SSTIs will be helpful for the further evaluation of the drug.

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.

Once-Daily Cefazolin and Probenecid for Skin and Soft Tissue Infections

OBJECTIVE

To review the pharmacokinetic and clinical evidence for the use of once-daily cefazolin and probenecid in the treatment of skin and soft tissue infections (SSTI).

DATA SOURCES

MEDLINE (1966–July 2003), EMBASE (1980–July 2003), and PubMed (1966–July 2003) databases for English language, human reports were searched. Search terms included cefazolin, probenecid, cellulitis, and soft tissue infections.

STUDY SELECTION AND DATA EXTRACTION

Studies that described pharmacokinetic and clinical outcomes that evaluated the use of cefazolin in conjunction with probenecid for SSTI were included. All studies were evaluated independently by both authors. For pharmacokinetic studies, the effect of probenecid on the pharmacokinetics of cefazolin was evaluated. For clinical trials, efficacy and safety endpoints were evaluated. For efficacy endpoints, definition of cure was used as defined by each trial.

DATA SYNTHESIS

In all 3 pharmacokinetic studies identified, the addition of probenecid to cefazolin therapy prolonged the half-life and increased serum concentrations of cefazolin. This process allowed serum concentrations to be above the minimal inhibitory concentrations (MIC) for the most likely skin pathogens ( Staphylococcus aureus, β-hemolytic streptococci) at the end of the dosing interval. In the first of 2 clinical trials, 7 (7%) of 96 patients receiving intravenous ceftriaxone 2 g and oral probenecid 1 g daily were reported to fail therapy compared with 8 (8%) of 98 patients receiving intravenous cefazolin 2 g and oral probenecid 1 g daily. In the second clinical trial, clinical success was reported in 51 (86%) of 59 patients receiving the same doses of cefazolin and probenecid as above compared with 55 (96%) of 57 patients receiving intravenous ceftriaxone 1 g and oral placebo daily.

CONCLUSIONS

Limited pharmacokinetic and clinical data suggest that intravenous cefazolin 2 g and oral probenecid 1 g daily is an effective regimen in the treatment of SSTI.

Treatment of bacterial skin and skin structure infections

Bacterial skin and skin structure infections (SSSIs) are among the most frequently seen infectious entities in the community setting and occasionally in the institutional setting. A wide variety of SSSIs exist, with cellulitis, impetigo and folliculitis being the most common. Most SSSIs are caused by aerobic staphylococci and streptococci, with aerobic Gram-negative bacilli and anaerobes being involved in more complicated infections. Systemic therapy with a variety of beta-lactams, macrolides and lincosamides (clindamycin) have been the cornerstone of SSSI therapy for many years. With the exception of mupirocin, topical therapy occupies a small therapeutic niche. Despite the emergence of antimicrobial resistance among the pathogens most commonly associated with SSSIs (for example, Streptococcus pyogenes and macrolides; Staphylococcus aureus and methicillin, vancomycin, penicillin and mupirocin), few treatment failures have been reported. The newest antimicrobials reviewed herein (linezolid, quinupristin/dalfopristin, gatifloxacin, gemifloxacin and moxifloxacin) are not a significant improvement upon older agents in the treatment of SSSIs. Perhaps this assessment will change if the penetrance of the antimicrobial resistance patterns described above reach a critical threshold and clinical failures become more widespread.

Once-daily intravenous cefazolin plus oral probenecid is equivalent to once-daily intravenous ceftriaxone plus oral placebo for the treatment of moderate-to-severe cellulitis in adults

A once-daily regimen of cefazolin (2 g intravenously [iv]) plus probenecid (1 g by mouth) was compared with a once-daily regimen of ceftriaxone (1 g iv) plus oral placebo in a randomized, double-blind equivalence trial of home-based therapy for moderate-to-severe cellulitis in adults. For the assessable recipients of cefazolin-probenecid (n=59) and ceftriaxone-placebo (n=57), clinical cure occurred at the end of treatment in 86% and 96% (P=.11), respectively, and was maintained at 1 month of follow-up in 96% and 91% (P=.55), respectively. The mean number of treatment doses (+/-standard deviation) given was similar in the 2 treatment arms (6.97+/-2.6 for cefazolin-probenecid and 6.12+/-2.1 for ceftriaxone-placebo; P=.06). The median antibiotic trough concentrations were 2.35 microgram/mL for cefazolin and 15.45 microgram/mL for ceftriaxone. Patients in the 2 treatment arms were similar with regard to overall rates of adverse reaction (P=.15), but nausea was more common among those in the cefazolin-probenecid arm (P=.048). The once-daily regimen of cefazolin-probenecid is a cheap, practical, and effective treatment option for moderate-to-severe cellulitis, and it avoids the need to use third-generation cephalosporins in most patients.

ED management of cellulitis: a review of five urban centers

Cellulitis is a common problem presenting to the emergency department (ED). This study examines the epidemiology of cellulitis in 5 Canadian urban EDs and determines the practice variation in this management among sites. From computerized provincial ED diagnosis information, 10% of cellulitis charts from April 1, 1997 to March 31, 1998 were randomly selected for review. All 5 EDs in one urban region were sampled; physicians were unaware of the study when seeing patients. A standardized audit form was used to collect information pertaining to visits for the incident infection case. Cases were excluded if simple cellulitis was not the primary diagnosis or if procedures such as incision and drainage were initially required. A total of 416 adult charts were retrospectively identified. The mean age was 46 years and 61% were men; 38% had seen another physician before the ED presentation. Cellulitis was most commonly located in the upper (41%) and lower (48%) extremities. Most cases were treated with intravenous cefazolin (58%; range among sites: 49%-66%); however, over 25 different antibiotics and doses were initially prescribed. Each case required a median of 4 (interquartile range [IQR]: 1, 9) ED visits. Some patients (14%) received an increase in dose (3%) or a change in antibiotic regimen (11%) during their treatment. Few patients (3%) required a second change in regimen. Specialist consultations were obtained in only 6% of patients and hospitalization was rare (7%). The most common discharge prescription was oral cephalexin (62%); however; many different regimens were prescribed. Cellulitis is a common ED problem which consumes considerable resources to treat. Considerable practice variation exists with respect to in-ED and post-ED management. These results suggest the need for the development of practice guidelines for the treatment of this common ED problem.

Teicoplanin for skin and soft tissue infections: An open study and a randomized, comparative trial versus cefazolin

An open trial and a multicenter, three-group, randomized trial versus cefazolin were performed to study the use of teicoplanin in the treatment of serious skin and soft tissue infections caused by Gram-positive bacteria. A total of 418 patients were entered into the randomized trial, 293 of whom were available for efficacy analysis, and 262 patients were entered in the open trial. The randomized trial had three arms: intramuscular (125 patients) vs intravenous (148 patients) teicoplanin vs cefazolin (145 patients). In both trials teicoplanin was administered once daily, originally as 3 mg/kg per day, with the option of higher doses in the open trial. Cefazolin was given at a dose of 1.5-4 g/day, in three divided doses. In the randomized trial, teicoplanin and cefazolin showed similar overall efficacy. The higher dose of teicoplanin (6 mg/kg) was significantly more effective than the lower dose (3 mg/kg), particularly in patients with diabetes. In the open trial, teicoplanin had a clinical success rate of 93%. There was no significant difference in the incidence of adverse events between the cefazolin and teicoplanin groups. Outpatient ambulatory therapy was shown to be a practical method of administering teicoplanin. Once-daily dosing with teicoplanin may allow physicians to treat skin and soft tissue infections on a totally outpatient basis.

Home-based treatment of cellulitis with twice-daily cefazolin

OBJECTIVE

To assess the clinical outcome and pharmacokinetics of therapy with cefazolin for patients with cellulitis in a hospital-in-the-home (HIH) program.

DESIGN

Observational study with outcome data compared with previously published reports of therapy for cellulitis.

SETTING

A university teaching hospital and HIH unit, July 1996-December 1997.

PARTICIPANTS

Patients with cellulitis were eligible for inclusion provided their medical condition was stable, they did not require surgical intervention, and their social circumstances allowed home-based therapy.

INTERVENTION

Cefazolin 2 g intravenously twice daily, with regular nursing and medical assessment.

MAIN OUTCOME MEASURES

Clinical efficacy; peak and trough serum concentrations of cefazolin.

RESULTS

Fifty-seven patients (37 were men) with a mean age of 48 years (range, 18-90 years) had 61 episodes of moderate to severe cellulitis (41, lower limb; 17, upper limb; and three, face). They received a median of 11 doses of cefazolin (range, 3-27 doses). Clinical outcomes were: cure in 54, improvement in one, treatment failure in three, and in the remaining three episodes the outcome was indeterminate. Cefazolin concentrations were measured in 27 patients. All peak concentrations were more than 40 micrograms/mL, while trough concentrations were all above the MIC90 of the expected pathogens: median, 3.2 micrograms/mL (range: 0.4-18.5 micrograms/mL). Cefazolin was well tolerated.

CONCLUSIONS

Twice-daily cefazolin 2 g intravenously is a convenient and effective option for home-based treatment of patients with cellulitis. Its clinical efficacy is comparable with other treatment regimens.

Ceftriaxone versus cefazolin with probenecid for severe skin and soft tissue infections

To evaluate the hypothesis that a single daily administration of cefazolin and probenecid and a single daily administration of ceftriaxone and probenecid would be equally effective, in combination with oral antibiotics, for the outpatient treatment of skin and soft tissue infections, a randomized, double-blind study was completed. Patients presenting to the Emergency Department with the primary diagnosis of cellulitis or soft tissue infection, excluding patients requiring immediate hospital admission, received either 2 g of ceftriaxone or 2 g of cefazolin, each with 1 g of probenecid, on a daily basis as outpatients from the Emergency Department. The patients were given a prescription for oral penicillin and cloxacillin for independent procurement. Outcome was assessed based on reduction in the size of the infected area, and the need for additional treatment (other antibiotics or hospital admission). A total of 194 patients were randomized to receive ceftriaxone (96) or cefazolin (98). There was no statistical difference in cause of infection, site of infection, duration of treatment, noncompliance or need for incision or drainage of the wound. The outcome, as determined by the ratio of the involved infected area on initial and last treatment day, and the frequency of failure were similar. The single daily administration of 2 g of either cefazolin, in combination with probenecid, or ceftriaxone are equivalent in efficacy in the outpatient treatment of skin and soft tissue infections. There is the potential for significant cost savings in utilizing outpatient cefazolin therapy over ceftriaxone for treatment of these infections.