title: In vitro antibacterial activity of doripenem against clinical isolates from French teaching hospitals: proposition of zone diameter breakpoints.
abstract: The aims of the study were to determine the in vitro activity of doripenem, a new carbapenem, against a large number of bacterial pathogens and to propose zone diameter breakpoints for clinical categorization in France according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) minimum inhibitory concentration (MIC) breakpoints. The MICs of doripenem were determined by the broth microdilution method against 1,547 clinical isolates from eight French hospitals. The disk diffusion test was performed (10-μg discs) according to the Comité de l'Antibiogramme de la Société Française de Microbiologie (CASFM) method. The MIC(50/90) (mg/L) values were as follows: methicillin-susceptible Staphylococcus aureus (MSSA) (0.03/0.25), methicillin-resistant Staphylococcus aureus (MRSA) (1/2), methicillin-susceptible coagulase-negative staphylococci (MSCoNS) (0.03/0.12), methicillin-resistant coagulase-negative staphylococci (MRCoNS) (2/8), Streptococcus pneumoniae (0.016/0.25), viridans group streptococci (0.016/2), β-hemolytic streptococci (≤0.008/≤0.008), Enterococcus faecalis (2/4), Enterococcus faecium (128/>128), Enterobacteriaceae (0.06/0.25), Pseudomonas aeruginosa (0.5/8), Acinetobacter baumannii (0.25/2), Haemophilus influenzae (0.12/0.25), and Moraxella catarrhalis (0.03/0.06). According to the regression curve, the zone diameter breakpoints were 24 and 19 mm for MICs of 1 and 4 mg/L, respectively. This study confirms the potent in vitro activity of doripenem against Pseudomonas aeruginosa, Acinetobacter, Enterobacteriaceae, MSSA, MSCoNS, and respiratory pathogens. According to the EUCAST MIC breakpoints (mg/L) ≤1/>4 for Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter, and ≤1/>1 for streptococci, pneumococci, and Haemophilus, the zone diameter breakpoints could be (mm) ≥24/<19 and ≥24/<24, respectively.
authors.affiliation: Service de Bactériologie-Virologie-Hygiène, CHU Henri Mondor, Assistance Publique-Hôpitaux de Paris, Université Paris 12, 51 Avenue du Maréchal de Lattre de Tassigny, 94010, Créteil Cedex, France. c.lascols@gmail.com
authors.forename: C
authors.initials: C
authors.lastname: Lascols
authors.forename: P
authors.initials: P
authors.lastname: Legrand
authors.forename: A
authors.initials: A
authors.lastname: Mérens
authors.forename: R
authors.initials: R
authors.lastname: Leclercq
authors.forename: L
authors.initials: L
authors.lastname: Armand-Lefevre
authors.forename: H B
authors.initials: HB
authors.lastname: Drugeon
authors.forename: M D
authors.initials: MD
authors.lastname: Kitzis
authors.forename: C
authors.initials: C
authors.lastname: Muller-Serieys
authors.forename: M E
authors.initials: ME
authors.lastname: Reverdy
authors.forename: M
authors.initials: M
authors.lastname: Roussel-Delvallez
authors.forename: C
authors.initials: C
authors.lastname: Moubareck
authors.forename: A
authors.initials: A
authors.lastname: Lemire
authors.forename: A
authors.initials: A
authors.lastname: Miara
authors.forename: M
authors.initials: M
authors.lastname: Gjoklaj
authors.forename: C-J
authors.initials: CJ
authors.lastname: Soussy
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D000077726:Doripenem; D005602:France; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology; D006095:Gram-Positive Cocci / Q000187:drug effects* / Q000302:isolation & purification; D006784:Hospitals, Teaching / Q000379:methods; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods / Q000592:standards
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D000077726:Doripenem