Pilot study the aim of which is to obtain reliable data on the tolerance, compliance and efficacy of Tedizolid used as prolonged (≥ 6 weeks) monotherapy or in combination therapy for the treatment of patients with orthopedic device infections due to Gram positive cocci.

Background: The antibiotic treatment of patients with orthopedic device infections (e.g. prosthetic joint and osteosynthesis) is limited by the tolerance of prolonged administration of antibiotics and the high level of antibiotic resistance of some pathogens.

The prolonged intravenous administration of antibiotics exposes the patients to the occurrence of adverse events and it is generally recommended to favor oral treatment provided high oral bioavailable agents can be used with regard to the patient's characteristics and the antibiotic susceptibility profile of the pathogens.

Gram positive cocci especially coagulase negative staphylococci (CoNS) are predominant bacteria responsible for orthopedic device infections. The use of the oxazolidinone agent Linezolid in these settings has been validated by some studies in particular in combination with Rifampin but both hematologic, neurologic and metabolic potential toxicity limits treatment durations of more than two to three weeks. The risk of drug-drug interaction with any product having a mono-amine-oxydase inhibitor (MAOI) activity is another limiting problem with Linezolid use.

In addition, the wide use of Linezolid has resulted in the emergence of CoNS carrying cfr genes responsible for high levels of Linezolid resistance. This is unfortunate as in many cases there is almost no other alternative for the oral treatment of orthopedic device infections due to these strains.

Tedizolid intrinsic properties may improve the oxazolidinone treatment long term safety. Plus tedizolid should be active on CoNS strains resistant to linezolid.

Objectives: Obtain reliable data on the tolerance, compliance and efficacy of Tedizolid used as prolonged (≥ 6 weeks) monotherapy or in combination therapy for the treatment of patients with orthopedic device infections due to Gram positive cocci.

Hypothesis: As no data are currently available on long term safety of Tedizolid treatment, the investigators will compare the results of the present study regarding tolerance and efficacy with those of a historical cohort of comparable patients from our cohorts treated with Linezolid monotherapy or combination therapy for equivalent indications (data published in Journal of Antimicrobial Chemotherapy Legout L et al..2010).

Study Design: Prospective multicenter cohort study.

The objectives of the study are :

(i) to assess the tolerance of TEDIZOLID determined by the proportion of patients who experienced any adverse event attributable to TEDIZOLID during treatment and during 6 weeks after the antibiotic treatment, and (ii) to assess the efficacy of TEDIZOLID as single agent treatment or combined therapy for orthopedic infections due to TEDIZOLID susceptible bacteria determined by the proportion of patient with remission of the infection (i.e. absence of any local and systemic sign of infection in relation with the initial infection, any surgery for an infectious reason at the initial site or death related to the initial infection) determined one year after the end of the antibiotic treatment.

Microbiologic data from failure cases will be recorded in order to assess the presence of Tedizolid-resistant strains, relapsing infections, or superinfection.

Treatment: Tedizolid 200 mg once a day, administered orally for the entire treatment will be prescribed in patients after the definite culture results of peroperative samples will be available.

Daily doses of the antibiotics associated with tedizolid will be at the discretion of the clinician and will have to follow the institutional therapeutical protocols.

Inclusion Criteria:

• Patient at least 18 years;
• Orthopedic device infection defined according to the French recommendations published in 2009 (Med Mal Infect 2009; 39:745-774) for which TEDIZOLID treatment is proposed according to the investigator's decision;
• Bacterial documentation of the infection will only be based on the results of reliable samples such as joint aspiration and peroperative samples.
• Requiring TEDIZOLID administration as a single antibiotic therapy or in combination therapy including another agent with proven activity against the involved pathogen(s);
• No contraindication to TEDIZOLID;
• Provide a signed informed consent for the trial.

Exclusion Criteria:

• pregnant women or of childbearing age without contraception, breastfeeding,
• intolerance to TEDIZOLID;
• allergy to LINEZOLID;
• bactéria non susceptible to TEDIZOLID;
• patient with uncertainty regarding the possibility to achieve one-year follow-up after the end of treatment.