title: A delivery system of linezolid to enhance the MRSA osteomyelitis prognosis: in vivo experimental assessment.
abstract: Staphylococcus aureus, a major responsible microorganism of osteomyelitis, represents a challenge to treat because of the poor penetration of antibiotics in bone and increasing minimum inhibitory concentrations (MICs) to glycopeptides. The calcium-deficient apatites (CDA), closer to the biological components found in bone and other calcified tissues, have osteoconductive properties. So, to process severe osseous infections, CDA can be used to deliver in the infectious site antibiotics like linezolid. The acute experimental osteomyelitis due to methicillin-resistant Staphylococcus aureus (MRSA) was induced in rabbit's femurs and surgery mimicking human procedures was performed at day three after inoculation. Animals were randomly assigned to treatment groups: L((IV)) [4-day linezolid IV infusion, human-equivalent dose of 10 mg/kg/12 h], L((CDA50%)) (100 mg CDA with linezolid 500 μg/mg) and L((CDA50%)) + L((IV)). Surviving bacteria were counted in bone marrow (BM) and bone (Bo) at day 3 (before treatment), day 7 (4-day treatment) or day 17 (14-day treatment). L(iv) was effective after a 4-day treatment with a log(10)CFU/g decrease of -2.63 ± 1.92 and -2.17 ± 1.58 in bone marrow and bone, respectively. CDA loaded with linezolid enhance the efficacy of the IV linezolid regimen by more than one log(10)CFU/g.
authors.affiliation: Faculté de Médecine, UPRES EA 3826, Université de Nantes, 1 rue Gaston Veil, Nantes 44000, France.
authors.forename: A
authors.initials: A
authors.lastname: Gaudin
authors.forename: C
authors.initials: C
authors.lastname: Jacqueline
authors.forename: H
authors.initials: H
authors.lastname: Gautier
authors.forename: C
authors.initials: C
authors.lastname: Desessard
authors.forename: V
authors.initials: V
authors.lastname: Le Mabecque
authors.forename: A-F
authors.initials: AF
authors.lastname: Miegeville
authors.forename: G
authors.initials: G
authors.lastname: Potel
authors.forename: J-M
authors.initials: JM
authors.lastname: Bouler
authors.forename: P
authors.initials: P
authors.lastname: Weiss
authors.forename: J
authors.initials: J
authors.lastname: Caillon
authors.forename: G
authors.initials: G
authors.lastname: Amador
mesh_terms: D000081:Acetamides / Q000008:administration & dosage*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D001031:Apatites / Q000008:administration & dosage*; D001853:Bone Marrow / Q000382:microbiology; D001842:Bone and Bones / Q000382:microbiology; D015169:Colony Count, Microbial; D004195:Disease Models, Animal; D016503:Drug Delivery Systems; D005260:Female; D000069349:Linezolid; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D010019:Osteomyelitis / Q000188:drug therapy* / Q000382:microbiology; D023303:Oxazolidinones / Q000008:administration & dosage*; D011817:Rabbits; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology; D016896:Treatment Outcome
chemical_list: D000081:Acetamides; D000900:Anti-Bacterial Agents; D001031:Apatites; D023303:Oxazolidinones; D000069349:Linezolid