In vitro activity of tigecycline against multidrug-resistant Enterobacteriaceae isolates from a Belgian hospital

• Published in: European journal of clinical microbiology & infectious diseases 2009-04, Vol.28 (4), p.381-384
• Main Authors: Naesens, R, Ursi, J. P, Van Schaeren, J, Jeurissen, A
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - pharmacology; Antibacterial agents; Antibiotics; Antibiotics. Antiinfectious agents. Antiparasitic agents; Bacteria; Belgium; beta-Lactam Resistance; Biological and medical sciences; Biomedical and Life Sciences; Biomedicine; Concise Article; Drug resistance; Drug Resistance, Multiple, Bacterial; E coli; Enterobacter; Enterobacteriaceae; Enterobacteriaceae - drug effects; Enterobacteriaceae - isolation & purification; Enterobacteriaceae Infections - microbiology; Escherichia coli; Gram-negative bacteria; Hospitals; Humans; Infectious diseases; Internal Medicine; Klebsiella; Medical Microbiology; Medical sciences; Microbial Sensitivity Tests; Minocycline - analogs & derivatives; Minocycline - pharmacology; Nosocomial infections; Pathogens; Pharmacology. Drug treatments; Streptococcus infections
• ISSN: 0934-9723; 1435-4373
• DOI: 10.1007/s10096-008-0629-9

Bacterial resistance among Gram-negative pathogens is a challenging clinical problem. Tigecycline has been developed specifically to overcome resistance. The aim of this study was to assess the in vitro activity of tigecycline against ESBL-producing Escherichia coli, ESBL-producing Klebsiella spp., and multidrug-resistant Enterobacter spp. Between May 2007 and March 2008, 26 strains of ESBL-producing Escherichia coli, 10 strains of ESBL-producing Klebsiella spp., and 27 strains of multidrug-resistant Enterobacter spp. were isolated consecutively from inpatients with a documented infection in which the collected isolate was identified as the probable causative organism. The in vitro susceptibility against tigecycline was measured by the E-test method. MIC₅₀ values were 1 μg/ml, 2 μg/ml, and 3 μg/ml respectively. MIC₉₀ values were respectively 1.5 μg/ml, 4 μg/ml, and 12 μg/ml. Nonsusceptibility rates of 35%, 100%, and 96% respectively were found using EUCAST breakpoints. Despite the limited number of strains tested, our in vitro data suggest that tigecycline is unsuitable for the treatment of infections with multidrug-resistant Enterobacteriaceae in our setting. Therefore, we suggest that larger multicenter studies should be conducted to reconsider the value of tigecycline for the treatment of infections with multidrug-resistant, Gram-negative bacteria.