Brève histoire du plan antibiotique du ministère de la Santé en France

Les mécanismes de résistance des bactéries ont été évoqués par Alexander Fleming dès les années 40. En France, les premières actions de lutte contre cette menace ont d’abord concerné les infections nosocomiales. Le premier plan gouvernemental de 1994 concernait avant tout l’hygiène des hôpitaux, sans chercher à réduire la consommation d’antibiotiques. À la fin des années 90, la coordination européenne a multiplié les rapports sur le sujet, conduisant, en France, à la création du premier Plan intersectoriel de lutte contre l’antibiorésistance et à la première grande campagne de communication. Depuis 2003, ce plan est moins visible et, surtout, la consommation d’antibiotiques est repartie à la hausse.Although, the antibioresistance is well known since the 40’s, the first governmental actions against this threat, in France, was first concerned by nosocomial infections. The first governmental Plan was focusing on this aspect of the problem, and did not attempt to reduce the consumption of antibiotics. At the end of the 90’s, the pressure of the European coordination led to the creation of another more ambitious Plan to tackle antibioresistance and to the first communication campaign. Since 2003, the Plan is less visible and the consumption of antibiotics is rising again

Emergence of daptomycin resistance in daptomycin-naïve rabbits with methicillin-resistant Staphylococcus aureus prosthetic joint infection is associated with resistance to host defense cationic peptides and mprF polymorphisms.

BackgroundPrevious studies of both clinically-derived and in vitro passage-derived daptomycin-resistant (DAP-R) Staphylococcus aureus strains demonstrated the coincident emergence of increased DAP MICs and resistance to host defense cationic peptides (HDP-R).MethodsIn the present investigation, we studied a parental DAP-susceptible (DAP-S) methicillin-resistant Staphylococcus aureus (MRSA) strain and three isogenic variants with increased DAP MICs which were isolated from both DAP-treated and DAP-untreated rabbits with prosthetic joint infections. These strains were compared for: in vitro susceptibility to distinct HDPs differing in size, structure, and origin; i.e.; thrombin-induced platelet microbicidal proteins [tPMPs] and human neutrophil peptide-1 [hNP-1]; cell membrane (CM) phospholipid and fatty acid content; CM order; envelope surface charge; cell wall thickness; and mprF single nucleotide polymorphisms (SNPs) and expression profiles.ResultsIn comparison with the parental strain, both DAP-exposed and DAP-naive strains exhibited: (i) significantly reduced susceptibility to each HDP (P<0.05); (ii) thicker cell walls (P<0.05); (iii) increased synthesis of CM lysyl-phosphatidylglycerol (L-PG); (iv) reduced content of CM phosphatidylglycerol (PG); and (v) SNPs within the mprF locus No significant differences were observed between parental or variant strains in outer CM content of L-PG, CM fluidity, CM fatty acid contents, surface charge, mprF expression profiles or MprF protein content. An isolate which underwent identical in vivo passage, but without evolving increased DAP MICs, retained parental phenotypes and genotype.ConclusionsTHESE RESULTS SUGGEST: i) DAP MIC increases may occur in the absence of DAP exposures in vivo and may be triggered by organism exposure to endogenous HDPs: and ii) gain-in-function SNPs in mprF may contribute to such HDP-DAP cross-resistance phenotypes, although the mechanism of this relationship remains to be defined

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

Short treatment duration for community-acquired pneumonia

International audiencePurpose 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 and quality of antibacterial generic products approved for human use: a systematic review.

International audienceBACKGROUND: Concerns have recently emerged about the efficacy and the quality of antibacterial generic products approved for use in humans. METHODS: We searched Medline and Embase for original research articles on antibacterial generic products published in English or French before July 2013. RESULTS: We selected 37 original research articles: 15 on β-lactams, 10 on glycopeptides, and 12 on other antibacterial agents. The majority of articles (73.0%) were published during 2008-2012. Study designs included analytical chemistry (n = 9), in vitro susceptibility studies (n = 14), animal experiments (n = 6, including 5 using the neutropenic mouse thigh infection model), and clinical studies in humans (n = 15). Of the 37 studies, 14 (37.8%) suggested that some generic products may be inferior to the innovator in terms of purity (n = 2), in vitro activity (n = 3), in vivo efficacy in experimental models (n = 4), clinical efficacy (n = 2), taste (n = 2), or compliance and acceptability in children (n = 1). The majority of in vitro studies (78.6%) found no significant difference between generic products and the innovator. Most (5/6) in vivo studies suggesting a difference between generic products and the innovator were performed in an animal model that is not validated for the evaluation of the efficacy of antibacterial agents. The level of evidence was constantly low in clinical studies. CONCLUSIONS: Published data on antibacterial generic products are limited and heterogeneous, thus precluding any attempt to generalize the study results. This systematic review suggests that additional evidence would be needed before considering a revision of the marketing authorization process for antibacterial generic products

Teicoplanin-Containing Cement Spacers for Treatment of Experimental Staphylococcus aureus Joint Prosthesis Infection

Using a rabbit model of methicillin-resistant Staphylococcus aureus knee-prosthesis infection, we studied the efficacy of teicoplanin cement alone or in combination with systemic intramuscular (i.m.) injections of teicoplanin. Seven days after infection, surgical debridement and removal of the infected prostheses were performed, and five rabbits were randomly assigned to one of five different treatment groups: untreated controls, prosthesis replacement by drug-free cement spacer, prosthesis replacement by teicoplanin-loaded cement spacer (1.2 g of teicoplanin/40 g of cement), i.m. injections of teicoplanin (20 mg/kg of body weight, twice a day for 7 days), or systemic antibiotic treatment combined with teicoplanin-loaded spacers. The most effective regimen combined systemic teicoplanin and antibiotic spacers

Emergence of Resistance in Normal Human Aerobic Commensal Flora during Telithromycin and Amoxicillin-Clavulanic Acid Treatments

Mean fecal global yeast counts increased similarly during 7 days of treatment with telithromycin (800 mg once daily) or amoxicillin-clavulanic acid (amoxiclav) (1 g of amoxicillin and 125 mg of clavulanic acid 3 times daily) in human volunteers and decreased slowly thereafter. On skin, coagulase-negative staphylococci of decreased susceptibility (DS) to telithromycin increased in the telithromycin group, whereas those with DS to methicillin increased in the amoxiclav group. A similar antibiotic-related shift towards homologous DS was observed for oral nongroupable streptococci (NGS), but in addition, the prevalence of NGS resistant to both classes of antibiotics was significantly greater in the amoxiclav group at days 8 (P < 0.01) and 45 (P < 0.015)

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

International audienceBackground: : 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 &lt; 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 &lt; 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