title: In vitro activity of tigecycline and comparators against Gram-positive and Gram-negative isolates collected from the Middle East and Africa between 2004 and 2011.
abstract: The Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) was established in 2004 to monitor longitudinal changes in bacterial susceptibility to numerous antimicrobial agents, specifically tigecycline. In this study, susceptibility among Gram-positive and Gram-negative isolates between 2004 and 2011 from the Middle East and Africa was examined. Antimicrobial susceptibilities were determined using Clinical and Laboratory Standards Institute (CLSI) interpretive criteria, and minimum inhibitory concentrations (MICs) were determined by broth microdilution methods. US Food and Drug Administration (FDA)-approved breakpoints were used for tigecycline. In total, 2967 Gram-positive and 6322 Gram-negative isolates were examined from 33 participating centres. All Staphylococcus aureus isolates, including meticillin-resistant S. aureus, were susceptible to tigecycline, linezolid and vancomycin. Vancomycin, linezolid, tigecycline and levofloxacin were highly active (>97.6% susceptibility) against Streptococcus pneumoniae, including penicillin-non-susceptible strains. All Enterococcus faecium isolates were susceptible to tigecycline and linezolid, including 32 vancomycin-resistant isolates. Extended-spectrum β-lactamases were produced by 16.6% of Escherichia coli and 32.9% of Klebsiella pneumoniae. More than 95% of E. coli and Enterobacter spp. were susceptible to amikacin, tigecycline, imipenem and meropenem. The most active agents against Pseudomonas aeruginosa and Acinetobacter baumannii were amikacin (88.0% susceptible) and minocycline (64.2% susceptible), respectively; the MIC90 (MIC required to inhibit 90% of the isolates) of tigecycline against A. baumannii was low at 2mg/L. Tigecycline and carbapenem agents were highly active against most Gram-negative pathogens. Tigecycline, linezolid and vancomycin showed good activity against most Gram-positive pathogens from the Middle East and Africa.
authors: Department of Internal Medicine, Division of Infectious Diseases, American University of Beirut Medical Center, P.O. Box 11-0236, Riad El-Solh, 1107 2020 Beirut, Lebanon. Electronic address: sk11@aub.edu.lb.
authors: Souha S
authors: SS
authors: Kanj
authors: Division of Medical Microbiology, Faculty of Health Sciences, University of Stellenbosch, Cape Town, South Africa; National Health Laboratory Service, Tygerberg Hospital, Cape Town, South Africa.
authors: Andrew
authors: A
authors: Whitelaw
authors: Pfizer Inc., Collegeville, PA 19426, USA.
authors: Michael J
authors: MJ
authors: Dowzicky
mesh_terms: D000349:Africa; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology; D006094:Gram-Positive Bacteria / Q000187:drug effects* / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D008877:Middle East; D008911:Minocycline / Q000031:analogs & derivatives* / Q000494:pharmacology; D000078304:Tigecycline
chemical_list: D000900:Anti-Bacterial Agents; D000078304:Tigecycline; D008911:Minocycline
keywords: Africa; Antimicrobial susceptibility; Gram-negative; Gram-positive; Middle East; Tigecycline