Exclusive oral antibiotic treatment for hospitalized community-acquired pneumonia: a post-hoc analysis of a randomized clinical trial.

OBJECTIVES: In this study, we aimed to assess the efficacy of different ways of administration and types of beta-lactams for hospitalized community-acquired pneumonia (CAP). METHODS: In this post-hoc analysis of randomized controlled trials (RCT) on patients hospitalized for CAP (pneumonia short treatment trial) comparing 3-day vs. 8-day durations of beta-lactams, which concluded to non-inferiority, we included patients who received either amoxicillin-clavulanate (AMC) or third-generation cephalosporin (3GC) regimens, and exclusively either intravenous or oral treatment for the first 3 days (followed by either 5 days of oral placebo or AMC according to randomization). The choice of route and molecule was left to the physician in charge. The main outcome was a failure at 15 days after the first antibiotic intake, defined as temperature >37.9°C, and/or absence of resolution/improvement of respiratory symptoms, and/or additional antibiotic treatment for any cause. The primary outcome according to the route of administration was evaluated through logistic regression. Inverse probability treatment weighting with a propensity score model was used to adjust for non-randomization of treatment routes and potential confounders. The difference in failure rates was also evaluated among several sub-populations (AMC vs. 3GC treatments, intravenous vs. oral AMC, patients with multi-lobar infection, patients aged ≥65 years old, and patients with CURB65 scores of 3-4). RESULTS: We included 200 patients from the original trial, with 93/200 (46.5%) patients only treated with intravenous treatment and 107/200 (53.5%) patients only treated with oral therapy. The failure rate at Day 15 was not significantly different among patients treated with initial intravenous vs. oral treatment [25/93 (26.9%) vs. 28/107 (26.2%), adjusted odds ratios (aOR) 0.973 (95% CI 0.519-1.823), p 0.932)]. Failure rates at Day 15 were not significantly different among the subgroup populations. DISCUSSION: Among hospitalized patients with CAP, there was no significant difference in efficacy between initial intravenous and exclusive oral treatment. TRIAL REGISTRATION: This trial is registered with ClinicalTrials.gov, NCT01963442.

Intensified screening for SARS-CoV-2 in 18 emergency departments in the Paris metropolitan area, France (DEPIST-COVID): A cluster-randomized, two-period, crossover trial.

BACKGROUND: Asymptomatic and paucisymptomatic infections account for a substantial portion of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) transmissions. The value of intensified screening strategies, especially in emergency departments (EDs), in reaching asymptomatic and paucisymptomatic patients and helping to improve detection and reduce transmission has not been documented. The objective of this study was to evaluate in EDs whether an intensified SARS-CoV-2 screening strategy combining nurse-driven screening for asymptomatic/paucisymptomatic patients with routine practice (intervention) could contribute to higher detection of SARS-CoV-2 infections compared to routine practice alone, including screening for symptomatic or hospitalized patients (control). METHODS AND FINDINGS: We conducted a cluster-randomized, two-period, crossover trial from February 2021 to May 2021 in 18 EDs in the Paris metropolitan area, France. All adults visiting the EDs were eligible. At the start of the first period, 18 EDs were randomized to the intervention or control strategy by balanced block randomization with stratification, with the alternative condition being applied in the second period. During the control period, routine screening for SARS-CoV-2 included screening for symptomatic or hospitalized patients. During the intervention period, in addition to routine screening practice, a questionnaire about risk exposure and symptoms and a SARS-CoV-2 screening test were offered by nurses to all remaining asymptomatic/paucisymptomatic patients. The primary outcome was the proportion of newly diagnosed SARS-CoV-2-positive patients among all adults visiting the 18 EDs. Primary analysis was by intention-to-treat. The primary outcome was analyzed using a generalized linear mixed model (Poisson distribution) with the center and center by period as random effects and the strategy (intervention versus control) and period (modeled as a weekly categorical variable) as fixed effects with additional adjustment for community incidence. During the intervention and control periods, 69,248 patients and 69,104 patients, respectively, were included for a total of 138,352 patients. Patients had a median age of 45.0 years [31.0, 63.0], and women represented 45.7% of the patients. During the intervention period, 6,332 asymptomatic/paucisymptomatic patients completed the questionnaire; 4,283 were screened for SARS-CoV-2 by nurses, leading to 224 new SARS-CoV-2 diagnoses. A total of 1,859 patients versus 2,084 patients were newly diagnosed during the intervention and control periods, respectively (adjusted analysis: 26.7/1,000 versus 26.2/1,000, adjusted relative risk: 1.02 (95% confidence interval (CI) [0.94, 1.11]; p = 0.634)). The main limitation of this study is that it was conducted in a rapidly evolving epidemiological context. CONCLUSIONS: The results of this study showed that intensified screening for SARS-CoV-2 in EDs was unlikely to identify a higher proportion of newly diagnosed patients. TRIAL REGISTRATION: Trial registration number: ClinicalTrials.gov NCT04756609.

Efficacy of ceftazidime/avibactam in various combinations for the treatment of experimental osteomyelitis in rabbits caused by OXA-48-/ESBL-producing Escherichia coli.

BACKGROUND: While the treatment of ESBL-producing Enterobacterales osteomyelitis relies on carbapenems, the optimal regimen for OXA48 types remains unclear. We evaluated the efficacy of ceftazidime/avibactam in different combinations in an experimental model of OXA-48-/ESBL-producing Escherichia coli osteomyelitis. METHODS: E. coli pACYC184 is a clinical strain harbouring blaOXA-48 and blaCTX-M-15 inserts, with 'increased exposure susceptibility' to imipenem (MIC, 2 mg/L), gentamicin (MIC, 0.5 mg/L), colistin (MIC, 0.25 mg/L), ceftazidime/avibactam (MIC, 0.094 mg/L) and fosfomycin (MIC, 1 mg/L), and resistance to ceftazidime (MIC, 16 mg/L). Osteomyelitis was induced in rabbits by tibial injection of 2 × 108 cfu of OXA-48/ESBL E. coli. Treatment started 14 days later for 7 days in six groups: (1) control, (2) colistin 150.000 IU/kg subcutaneously (SC) q8h, (3) ceftazidime/avibactam 100/25 mg/kg SC q8h, (4) ceftazidime/avibactam + colistin, (5) ceftazidime/avibactam + fosfomycin 150 mg/kg SC q12h, (6) ceftazidime/avibactam + gentamicin 15 mg/kg intramuscularly (IM) q24h. Treatment was evaluated at Day 24 according to bone cultures. RESULTS: In vitro, time-kill curves of ceftazidime/avibactam in combination showed a synergistic effect. In vivo, compared with controls, rabbits treated with colistin alone had similar bone bacterial density (P = 0.50), whereas ceftazidime/avibactam alone or in combinations significantly decreased bone bacterial densities (P = 0.004 and P < 0.0002, respectively). Bone sterilization was achieved using ceftazidime/avibactam in combination with colistin (91%) or fosfomycin (100%) or gentamicin (100%) (P < 0.0001), whereas single therapies were not different from controls. No ceftazidime/avibactam-resistant strains emerged in rabbits treated, regardless of the combination. CONCLUSIONS: In our model of E. coli OXA-48/ESBL osteomyelitis, ceftazidime/avibactam in combination was more effective than any single therapy, whatever the companion drug used (gentamicin or colistin or fosfomycin).

Short treatment duration for community-acquired pneumonia.

PURPOSE OF REVIEW: Lower respiratory tract infections are one of the most common indications for antibiotic use in community and hospital settings. Usual guidelines for adults with community-acquired pneumonia (CAP) recommend 5-7 days of antibiotic treatment. In daily practice, physicians often prescribe 9-10 days of antibiotic treatment. Among available strategies to decrease antibiotic use, possibly preventing the emergence of bacterial resistance, reducing treatment durations is the safest and the most acceptable to clinicians. We aim to review data evaluating the efficacy of short antibiotic duration in adult CAP and which criteria can help clinicians to reduce antibiotic treatment. RECENT FINDINGS: Several studies and meta-analyses demonstrated that the treatment duration of 7 days or less was sufficient for CAP. Two trials found that 3-day treatments were effective, even in hospitalized CAP.To customize and shorten duration, clinical and biological criteria have been studied and reflect patient's response. Indeed, stability criteria were recently shown to be effective to discontinue antibiotic treatment. Procalcitonin was also studied but never compared with clinical criteria. SUMMARY: Treatment duration for CAP is still under debate, but several studies support short durations. Clinical criteria could be possibly used to discontinue antibiotic treatment.

Efficacy of ceftazidime-avibactam in various combinations for the treatment of experimental osteomyelitis due to Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae.

BACKGROUND: Optimal treatment of carbapenemase-producing Enterobacterales (CPE) bone infections is poorly defined. This study evaluated the efficacy of the novel beta-lactam-beta-lactamase inhibitor-ceftazidime-avibactam (CAZ-AVI)-with different antibiotic combinations in an experimental model of CPE osteomyelitis. METHODS: KPC-99YC is a clinical strain of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae with intermediate susceptibility to meropenem (MIC 4 mg/L), gentamicin (MIC 0.25 mg/L), colistin (MIC 0.25 mg/L), fosfomycin (MIC 4 mg/L) and ceftazidime-avibactam (MIC 1 mg/L). Time-kill curves were performed at 4x MIC. Osteomyelitis was induced in rabbits by tibial injection of 2×108 CFU of KPC-99YC. Six groups started treatment 14 days later for 7 days: control, colistin, CAZ-AVI, CAZ-AVI plus gentamicin, CAZ-AVI plus colistin and CAZ-AVI plus fosfomycin. Antibiotic dosages were selected to simulate plasma concentrations obtained in humans. Treatment was evaluated according to bone cultures quantified in log10 CFU. RESULTS: In vitro, CAZ-AVI plus colistin or gentamicin were rapidly bactericidal in contrast with CAZ-AVI plus fosfomycin. In vivo, compared with controls, colistin alone (P = 0.045) and CAZ-AVI alone or in combination significantly lowered bone bacterial counts (P < 0.001). Bone sterilisation was achieved in 67% and 100% of animals with combinations of CAZ-AVI plus colistin or gentamicin (P = 0.001 and P < 0.001, respectively) whereas other treatments were no different from controls. CAZ-AVI plus gentamicin provided greater bone bacterial reduction than CAZ-AVI plus colistin (P = 0.033). No CAZ-AVI-resistant strains emerged in treated rabbits, regardless of combination. CONCLUSIONS: CAZ-AVI plus gentamicin was the best effective combination therapy. Combinations with CAZ-AVI appear to be a promising treatment of KPC-producing Klebsiella pneumoniae osteomyelitis.

Factors Associated With Treatment Failure in Moderately Severe Community-Acquired Pneumonia: A Secondary Analysis of a Randomized Clinical Trial.

Importance: Failure of treatment is the most serious complication in community-acquired pneumonia (CAP). Objective: To assess the potential risk factors for treatment failure in clinically stable patients with CAP. Design, Setting, and Participants: This secondary analysis assesses data from a randomized clinical trial on CAP (Pneumonia Short Treatment [PTC] trial) conducted from December 19, 2013, to February 1, 2018. Data analysis was performed from July 18, 2019, to February 15, 2020. Patients hospitalized at 1 of 16 centers in France for moderately severe CAP who were clinically stable at day 3 of antibiotic treatment were included in the PTC trial and analyzed in the per-protocol trial population. Interventions: Patients were randomly assigned (1:1) on day 3 of antibiotic treatment to receive ß-lactam (amoxicillin-clavulanate [1 g/125 mg] 3 times daily) or placebo for 5 extra days. Main Outcomes and Measures: The main outcome was failure at 15 days after first antibiotic intake, defined as a temperature greater than 37.9 °C and/or absence of resolution or improvement of respiratory symptoms and/or additional antibiotic treatment for any cause. The association among demographic characteristics, baseline clinical and biological variables available (ie, at the first day of ß-lactam treatment), and treatment failure at day 15 among the per-protocol trial population was assessed by univariate and multivariable logistic regressions. Results: Overall, 310 patients were included in the study; this secondary analysis comprised 291 patients (174 [59.8%] male; mean [SD] age, 69.6 [18.5] years). The failure rate was 26.8%. Male sex (odds ratio [OR], 1.74; 95% CI, 1.01-3.07), age per year (OR, 1.03; 95% CI, 1.01-1.05), Pneumonia Severe Index score (OR, 1.01; 95% CI, 1.00-1.02), the presence of chronic lung disease (OR, 1.85; 95% CI, 1.03-3.30), and creatinine clearance (OR, 0.99; 95% CI, 0.98-1.00) were significantly associated with failure in the univariate analysis. When the Pneumonia Severe Index score was excluded to avoid collinearity with age and sex in the regression model, only male sex (OR, 1.92; 95% CI, 1.08-3.49) and age (OR, 1.02; 95% CI, 1.00-1.05) were associated with failure in the multivariable analysis. Conclusions and Relevance: In this secondary analysis of a randomized clinical trial, among patients with CAP who reached clinical stability after 3 days of antibiotic treatment, only male sex and age were associated with higher risk of failure, independent of antibiotic treatment duration and biomarker levels. Another randomized clinical trial is needed to evaluate the impact of treatment duration in populations at higher risk for treatment failure.

Acceptability of Nurse-Driven HIV Screening for Key Populations in Emergency Departments: A Mixed-Methods Study.

BACKGROUND: Optimizing care continuum entry interventions is key to ending the HIV epidemic. Offering HIV screening to key populations in emergency departments (EDs) is a strategy that has been demonstrated to be effective. Analyzing patient and provider perceptions of such screening can help identify implementation facilitators and barriers. OBJECTIVES: The aim of this study was to investigate the acceptability of offering nurse-driven HIV screening to key populations based on data collected from patients, nurses, and other service providers. METHODS: This convergent mixed-methods study was a substudy of a cluster-randomized two-period crossover trial conducted in eight EDs to evaluate the effectiveness of the screening strategy. During the DICI-VIH (Dépistage Infirmier CIblé du VIH) trial, questionnaires were distributed to patients aged 18-64 years. Based on their responses, nurses offered screening to members of key populations.Over 5 days during the intervention period in four EDs, 218 patients were secondarily questioned about the acceptability of screening. Nurses completed 271 questionnaires pre- and posttrial regarding acceptability in all eight EDs. Descriptive analyses were conducted on these quantitative data. Convenience and purposeful sampling was used to recruit 53 providers to be interviewed posttrial. Two coders conducted a directed qualitative content analysis of the interview transcripts independently. RESULTS: The vast majority of patients (95%) were comfortable with questions asked to determine membership in key populations and agreed (89%) that screening should be offered to key populations in EDs. Nurses mostly agreed that offering screening to key populations was well accepted by patients (62.2% pretrial and 71.4% posttrial), was easy to implement, and fell within the nursing sphere of competence. Pretrial, 73% of the nurses felt that such screening could be implemented in EDs. Posttrial, the proportion was 41%. Three themes emerged from the interviews: preference for targeted screening and a written questionnaire to identify key populations, facilitators of long-term implementation, and implementation barriers. Nurses were favorable to such screening provided specific conditions were met regarding training, support, collective involvement, and flexibility of application to overcome organizational and individual barriers. DISCUSSION: Screening for key populations was perceived as acceptable and beneficial by patients and providers. Addressing the identified facilitators and barriers would help increase screening implementation in EDs.

Discontinuing ß-lactam treatment after 3 days for patients with community-acquired pneumonia in non-critical care wards (PTC): a double-blind, randomised, placebo-controlled, non-inferiority trial.

BACKGROUND: Shortening the duration of antibiotic therapy for patients admitted to hospital with community-acquired pneumonia should help reduce antibiotic consumption and thus bacterial resistance, adverse events, and related costs. We aimed to assess the need for an additional 5-day course of ß-lactam therapy among patients with community-acquired pneumonia who were stable after 3 days of treatment. METHODS: We did this double-blind, randomised, placebo-controlled, non-inferiority trial (the Pneumonia Short Treatment [PTC]) in 16 centres in France. Adult patients (aged ≥18 years) admitted to hospital with moderately severe community-acquired pneumonia (defined as patients admitted to a non-critical care unit) and who met prespecified clinical stability criteria after 3 days of treatment with ß-lactam therapy were randomly assigned (1:1) to receive ß-lactam therapy (oral amoxicillin 1 g plus clavulanate 125 mg three times a day) or matched placebo for 5 extra days. Randomisation was done using a web-based system with permuted blocks with random sizes and stratified by randomisation site and Pneumonia Severity Index score. Participants, clinicians, and study staff were masked to treatment allocation. The primary outcome was cure 15 days after first antibiotic intake, defined by apyrexia (temperature ≤37·8°C), resolution or improvement of respiratory symptoms, and no additional antibiotic treatment for any cause. A non-inferiority margin of 10 percentage points was chosen. The primary outcome was assessed in all patients who were randomly assigned and received any treatment (intention-to-treat [ITT] population) and in all patients who received their assigned treatment (per-protocol population). Safety was assessed in the ITT population. This study is registered with ClinicalTrials.gov, NCT01963442, and is now complete. FINDINGS: Between Dec 19, 2013, and Feb 1, 2018, 706 patients were assessed for eligibility, and after 3 days of ß-lactam treatment, 310 eligible patients were randomly assigned to receive either placebo (n=157) or ß-lactam treatment (n=153). Seven patients withdrew consent before taking any study drug, five in the placebo group and two in the ß-lactam group. In the ITT population, median age was 73·0 years (IQR 57·0-84·0) and 123 (41%) of 303 participants were female. In the ITT analysis, cure at day 15 occurred in 117 (77%) of 152 participants in the placebo group and 102 (68%) of 151 participants in the ß-lactam group (between-group difference of 9·42%, 95% CI -0·38 to 20·04), indicating non-inferiority. In the per-protocol analysis, 113 (78%) of 145 participants in the placebo treatment group and 100 (68%) of 146 participants in the ß-lactam treatment group were cured at day 15 (difference of 9·44% [95% CI -0·15 to 20·34]), indicating non-inferiority. Incidence of adverse events was similar between the treatment groups (22 [14%] of 152 in the placebo group and 29 [19%] of 151 in the ß-lactam group). The most common adverse events were digestive disorders, reported in 17 (11%) of 152 patients in the placebo group and 28 (19%) of 151 patients in the ß-lactam group. By day 30, three (2%) patients had died in the placebo group (one due to bacteraemia due to Staphylococcus aureus, one due to cardiogenic shock after acute pulmonary oedema, and one due to heart failure associated with acute renal failure) and two (1%) in the ß-lactam group (due to pneumonia recurrence and possible acute pulmonary oedema). INTERPRETATION: Among patients admitted to hospital with community-acquired pneumonia who met clinical stability criteria, discontinuing ß-lactam treatment after 3 days was non-inferior to 8 days of treatment. These findings could allow substantial reduction of antibiotic consumption. FUNDING: French Ministry of Health.

Reasons for Litigation in Arthroplasty Infections and Lessons Learned.

BACKGROUND: Infections complicate a minority of orthopaedic arthroplasties but are the leading cause of malpractice claims. The basis for the claims is unclear. The objective of this study was to identify the main deviations from current recommendations by reviewing patient files recorded by a major French medical liability-specialized insurance company for private practitioners (MACSF [Mutuelle d'Assurance du Corps de Santé Français]) and to analyze legal claims and outcomes of litigation. METHODS: All claims data for periprosthetic joint infections were analyzed retrospectively from 2010 to 2014. Treatment strategies were compared with therapeutic guidelines published by medical societies. RESULTS: Forty-five claims for periprosthetic joint infection were recorded; 82% of patients were men and the mean patient age was 63 years. Twenty-one patients (47%) had a knee arthroplasty, 21 had a hip arthroplasty, 2 had a shoulder arthroplasty, and 1 had an ankle arthroplasty. Twenty-three infections (51%) occurred within 1 month postoperatively. Staphylococcus aureus was isolated from intraoperative samples in 36% of the cases (including 25% of these with methicillin-resistant strains), and coagulase-negative staphylococci were isolated in 51% (44% methicillin-resistant strains) of the cases. Treatment lasted for a median of 9.5 months (range, 1.5 to 96 months), with a median of 6 months (range, 1.5 to 20 months) of antibiotics and 3 surgical procedures (range, 0 to 7 surgical procedures). A total of 18% of patients had antibiotic-related side effects, 2% of patients died, and 76% of patients had persistent sequelae. An infectious disease specialist's advice was required for 56% of the patients. Discordances with therapeutic guidelines were found in 76% of the patient files, including delay in diagnosis (44%) and inadequate medical treatment (18%) or medico-surgical treatment (13%). CONCLUSIONS: Late diagnosis of early postoperative infections appears to be the major cause of inappropriate management and malpractice litigation. Discordance with current guidelines was identified. Early consultation with an infectious disease specialist may help to reduce malpractice claims. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Implementation of Nurse-Driven HIV Screening Targeting Key Populations in Emergency Departments: A Multilevel Analysis From the DICI-VIH Trial.

BACKGROUND: In countries with concentrated HIV epidemics, optimizing screening to reach individuals with undiagnosed infection is essential. The DICI-VIH study, a cluster-randomized crossover trial conducted in eight French emergency departments (EDs), found that a strategy combining nurse-driven targeted HIV screening with routine diagnostic testing was effective. AIM: The aim was to investigate factors associated with the implementation of HIV screening targeting key populations in EDs. METHODS: A self-administered questionnaire was distributed at registration to patients aged 18-64 years and able to give consent during the DICI-VIH intervention. Based on their responses, those belonging to key populations were offered a rapid test by triage nurses. Two key stages of the process were evaluated: questionnaire distribution by providers and test acceptance by patients. Patient information, daily workload, and ED characteristics were collected. The associations between these variables and (a) the proportion of questionnaires distributed and (b) the proportion of tests accepted were evaluated using multilevel modeling in order to examine differences in screening implementation between EDs. RESULTS: Questionnaire distribution proportions varied from 23% to 48% across EDs. They were higher on weekdays than weekends (odds ratio, OR: 3.77; 95% CI: 3.57-3.99) and when research staff participated (OR: 1.31; 95% CI: 1.26-1.37). They decreased over time (OR: 0.76; 95% CI: 0.71-0.82; 4th [Q3] vs. 1st quartile [Q0] of intervention days) and with increased patient flow (OR: 0.61; 95% CI: 0.56-0.67; Q3 vs. Q0 of eligible patients). Test acceptance varied from 64% to 77% across EDs, increased with research staff participation (OR 1.20; 95% CI: 1.03-1.40), and decreased over time (OR: 0.75; 95% CI: 0.60-0.92; Q3 vs. Q0). Patients who accepted were more likely to be younger (OR: 0.76; 95% CI: 0.61-0.96; 50-64-year-old vs. 30-39-year-old patients). LINKING EVIDENCE TO ACTION: Patient flow, intervention duration, weekdays, and research staff participation were important determinants of targeted screening implementation. These findings could help guide future implementation in similar settings.

Efficacy of colistin alone and in various combinations for the treatment of experimental osteomyelitis due to carbapenemase-producing Klebsiella pneumoniae.

OBJECTIVES: In a new experimental model of carbapenemase-producing Klebsiella pneumoniae osteomyelitis we evaluated the efficacy of colistin alone and in various combinations and examined the emergence of colistin-resistant strains and cross-resistance to host defence peptides (HDPs). METHODS: KPC-99YC is a clinical strain with intermediate susceptibility to meropenem (MIC = 4 mg/L) and full susceptibility to gentamicin, colistin and tigecycline (MICs = 1 mg/L) and fosfomycin (MIC = 32 mg/L). Time-kill curves were performed at 4× MIC. Osteomyelitis was induced in rabbits by tibial injection of 2 × 108 cfu. Treatment started 14 days later for 7 days in seven groups: (i) control; (ii) colistin; (iii) colistin + gentamicin; (iv) colistin + tigecycline; (v) colistin + meropenem; (vi) colistin + meropenem + gentamicin; and (vii) colistin + fosfomycin. RESULTS: In vitro, colistin was rapidly bactericidal, but regrowth occurred after 9 h. Combinations of colistin with meropenem or fosfomycin were synergistic, whereas combination with tigecycline was antagonistic. In vivo, colistin alone was not effective. Combinations of colistin with meropenem or fosfomycin were bactericidal (P < 0.001) and the addition of gentamicin enhanced the efficacy of colistin + meropenem (P = 0.025). Tigecycline reduced the efficacy of colistin (P = 0.007). Colistin-resistant strains emerged in all groups except colistin + fosfomycin and two strains showed cross-resistance to HDP LL-37. CONCLUSIONS: In this model, combinations of colistin plus meropenem, with or without gentamicin, or colistin plus fosfomycin were the only effective therapies. The combination of colistin and tigecycline should be administered with caution, as it may be antagonistic in vitro and in vivo.

Native joint septic arthritis due to Clostridium tarantellae.

Clostridium is a diverse genus including more than 200 species involved in varied clinical presentations in infectious diseases. Septic arthritis caused by Clostridium sp. are however uncommon. We report here the first septic arthritis due to Clostridium tarantellae, formerly called Eubacterium tarantellae, in a patient under anti-TNF therapy.

Benefits of Polymerase Chain Reaction Combined With Culture for the Diagnosis of Bone and Joint Infections: A Prospective Test Performance Study.

BACKGROUND: The microbiological diagnosis of bone and joint infections (BJI) currently relies on cultures, and the relevance of molecular methods is still debated. The aim of this study was to determine whether polymerase chain reaction (PCR) could improve the etiological diagnosis of BJI. METHODS: A prospective study was conducted during a 4-year period at Lariboisiere University Hospital (Paris, France), including patients with suspicion of infectious spondylodiscitis, septic arthritis, prosthetic joint infections, and respective noninfected groups. Clinical and radiological data were collected at inclusion and during follow-up. All samples were analyzed by conventional cultures and 16S ribosomal deoxyribonucleic acid (rDNA) gene (16S-PCR). Specific cultures and PCR targeting Mycobacterium tuberculosis were also performed for spondylodiscitis samples. Case records were subsequently analyzed by an independent expert committee to confirm or invalidate the suspicion of infection and definitively classify the patients in a case or control group. The sensitivity of the combination of culture and PCR was compared with culture alone. RESULTS: After expert committee analysis, 105 cases of BJI cases and 111 control patients were analyzed. The most common pathogens of BJI were staphylococci (30%), M tuberculosis (19%), and streptococci (14%). Adding PCR enhanced the sensitivity compared with culture alone (1) for the diagnosis of M tuberculosis spondylodiscitis (64.4% vs 42.2%; P < .01) and (2) for nonstaphylococci BJI (81.6% vs 71.3%; P < .01). It is interesting to note that 16S-PCR could detect BJI due to uncommon bacteria such as Mycoplasma and fastidious bacteria. CONCLUSIONS: Our study showed the benefit of 16S-PCR and PCR targeting M tuberculosis as add-on tests in cases of suspected BJI.

In vivo daptomycin efficacy against experimental vancomycin-resistant Enterococcus faecium endocarditis.

Objectives: Daptomycin has become a first-line therapeutic option for vancomycin-resistant Enterococcus faecium infective endocarditis (IE). Although high doses (≥8 mg/kg) are often recommended, optimal doses, particularly for strains with MICs close to the susceptibility breakpoint (4 mg/L), are still debated. Methods: Daptomycin efficacy at doses equivalent to 8 mg/kg daptomycin (DAP8) and 12 mg/kg daptomycin (DAP12) in humans was evaluated in a rabbit model of aortic valve IE induced by 108 cfu of E. faecium reference strain Aus0004 (daptomycin MIC = 2 mg/L) or its in vitro mutant strain Mut4 (daptomycin MIC = 4 mg/L). Treatment began 48 h post-inoculation and lasted 5 days. Results: With Aus0004, the median log10 cfu/g of vegetations was significantly lower after DAP8 and DAP12 versus controls [6.05 (n = 12) and 2.15 (n = 10) versus 9.14 (n = 11), respectively; P < 0.001], with DAP12 being more effective than DAP8 concerning vegetation bacterial load (P < 0.001) and percentages of sterile vegetations (100% versus 0%, respectively; P < 0.001). Daptomycin-resistant Aus0004 mutants were detected in 8.3% of DAP8-treated vegetations. With Mut4, the median log10 cfu/g of vegetations was significantly lower after DAP8 and DAP12 versus controls [7.7 (n = 11) and 6.95 (n = 10) versus 9.59 (n = 11), respectively; P = 0.001 and P = 0.002], without any between-dose difference, but no vegetation was sterile. Moreover, 7 of 11 (63.6%) and 7 of 9 (77.8%) vegetations contained resistant mutants after DAP8 and DAP12, respectively. Conclusions: DAP12 was the most successful strategy against IE due to a WT E. faecium strain (daptomycin MIC = 2 mg/L). To treat IE strains with MIC = 4 mg/L, DAP8 or DAP12 monotherapy was poorly effective with the risk of resistant mutant emergence. Reassessment of the daptomycin susceptibility breakpoint for enterococci seems necessary.

Grafting of Bioactive Polymers with Various Architectures: A Versatile Tool for Preparing Antibacterial Infection and Biocompatible Surfaces.

The aim of this Research Article is to present three different techniques of poly(sodium styrene sulfonate) (polyNaSS) covalent grafting onto titanium (Ti) surfaces and study the influence of their architecture on biological response. Two of them are "grafting from" techniques requiring an activation step either by thermal or UV irradiation. The third method is a "grafting to" technique involving an anchorage molecule onto which polyNaSS synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization is clicked. The advantage of the "grafting to" technique when compared to the "grafting from" technique is the ability to control the architecture and length of the grafted polymers on the Ti surface and their influence on the biological responses. This investigation compares the effect of the three different grafting processes on the in vitro biological responses of bacteria and osteoblasts. Overall outcomes of this investigation confirmed the significance of the sulfonate functional groups on the biological responses, regardless of the grafting method. In addition, results showed that the architecture and distribution of grafted polyNaSS on Ti surfaces alter the intensity of the bacteria response mediated by fibronectin.

Targeted HIV Screening in Eight Emergency Departments: The DICI-VIH Cluster-Randomized Two-Period Crossover Trial.

STUDY OBJECTIVE: This study compares the effectiveness and cost-effectiveness of nurse-driven targeted HIV screening alongside physician-directed diagnostic testing (intervention strategy) with diagnostic testing alone (control strategy) in 8 emergency departments. METHODS: In this cluster-randomized, 2-period, crossover trial, 18- to 64-year-old patients presenting for reasons other than potential exposure to HIV were included. The strategy applied first was randomly assigned. During both periods, diagnostic testing was prescribed by physicians following usual care. During the intervention periods, patients were asked to complete a self-administered questionnaire. According to their answers, the triage nurse suggested performing a rapid test to patients belonging to a high-risk group. The primary outcome was the proportion of new diagnoses among included patients, which further refers to effectiveness. A secondary outcome was the intervention's incremental cost (health care system perspective) per additional diagnosis. RESULTS: During the intervention periods, 74,161 patients were included, 16,468 completed the questionnaire, 4,341 belonged to high-risk groups, and 2,818 were tested by nurses, yielding 13 new diagnoses. Combined with 9 diagnoses confirmed through 97 diagnostic tests, 22 new diagnoses were established. During the control periods, 74,166 patients were included, 92 were tested, and 6 received a new diagnosis. The proportion of new diagnoses among included patients was higher during the intervention than in the control periods (3.0 per 10,000 versus 0.8 per 10,000; difference 2.2 per 10,000, 95% CI 1.3 to 3.6; relative risk 3.7, 95% CI 1.4 to 9.8). The incremental cost was €1,324 per additional new diagnosis. CONCLUSION: The combined strategy of targeted screening and diagnostic testing was effective.

Phenol-Soluble Modulins Contribute to Early Sepsis Dissemination Not Late Local USA300-Osteomyelitis Severity in Rabbits.

INTRODUCTION: In bone and joint infections (BJIs), bacterial toxins are major virulence factors: Panton-Valentine leukocidin (PVL) expression leads to severe local damage, including bone distortion and abscesses, while α-hemolysin (Hla) production is associated with severe sepsis-related mortality. Recently, other toxins, namely phenol-soluble modulins (PSMs) expressed by community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strain USA300 (LAC WT) were shown to have ex vivo intracellular cytotoxic activity after S. aureus invasion of osteoblasts, but their in vivo contribution in a relatively PVL-sensitive osteomyelitis model remains poorly elucidated. MATERIALS AND METHODS: We compared the outcomes of experimental rabbit osteomyelitises induced with pvl+hla+psms+ LAC WT and its isogenic Δpsm derivatives (LAC Δpsmα and LAC Δpsmαßhld) using an inoculum of 3 × 108 CFUs. Mortality, hematogenous spread (blood culture, spleen and kidney), lung and bone involvements were assessed in two groups (non-survivors of severe sepsis and survivors sacrificed on day (D) 14). RESULTS: Severe sepsis-related mortality tended to be lower for Δpsm derivatives (Kaplan-Meier curves, P = .06). Non-survivors' bone LAC-Δpsmα (6.9 log10 CFUs/g of bone, P = .04) or -Δpsmαßhld (6.86 log10 CFUs/g of bone, P = .014) densities were significantly higher than LAC WT (6.43 log10 CFUs/g of bone). Conversely, lung Δpsmαßhld CFUs were significantly lower than LAC WT (P = .04). LAC Δpsmα, Δpsmαßhld and WT induced similar bone damage in D14 survivors, with comparable bacterial densities (respectively: 5.89, 5.91, and 6.15 log10 CFUs/g of bone). Meanwhile, pulmonary histological scores of inflammation were significantly higher for LAC Δpsmα- and Δpsmαßhld-infected rabbits compared to LAC WT (P = .04 and .01, respectively) but with comparable lung bacterial densities. CONCLUSION: Our experimental results showed that deactivating PSM peptides significantly limited bacterial dissemination from bone during the early phase of infection, but did not affect local severity of USA300 rabbit osteomyelitis.