Global in vitro activity of tigecycline and comparator agents: Tigecycline Evaluation and Surveillance Trial 2004–2013

Abstract

BackgroundThe Tigecycline Evaluation and Surveillance Trial (TEST) is a global antimicrobial susceptibility surveillance study which has been ongoing since 2004. This report examines the in vitro activity of tigecycline and comparators against clinically important pathogens collected globally between 2004 and 2013.MethodsAntimicrobial susceptibility was determined using guidelines published by the Clinical and Laboratory Standards Institute. The Cochran Armitage Trend Test was used to identify statistically significant changes in susceptibility between 2004 and 2013.ResultsAmong the Enterobacteriaceae susceptibility was highest to the carbapenems [imipenem 97.1% (24,655/25,381), meropenem 97.0% (90,714/93,518)], tigecycline (97.0%, 115,361/118,899) and amikacin (96.9%, 115,200/118,899). Against Acinetobacter baumannii the highest rates of susceptibility were for minocycline (84.5%, 14,178/16,778) and imipenem (80.0%, 3,037/3,795). The MIC90 for tigecycline was 2 mg/L. 40% (6,743/16,778) of A. baumannii isolates were multidrug-resistant. Enterococci were highly susceptible to tigecycline and linezolid (>99%); vancomycin resistance was observed among 2% of Enterococcus faecalis (325/14,615) and 35% of Enterococcus faecium (2,136/6,167) globally. 40% (14,647/36,448) of Staphylococcus aureus were methicillin-resistant while 15% (2,152/14,562) of Streptococcus pneumoniae were penicillin-resistant. Against S. aureus and S. pneumoniae susceptibility to linezolid, vancomycin, and tigecycline was ≥99.9%. Globally, 81% (331/410) of statistically significant susceptibility changes during the study period were decreases in susceptibility.ConclusionsAmikacin, the carbapenems, and tigecycline were active against most gram-negative pathogens while linezolid, tigecycline, and vancomycin retained activity against most gram-positive pathogens collected in TEST during 2004–2013.Electronic supplementary materialThe online version of this article (doi:10.1186/s12941-015-0085-1) contains supplementary material, which is available to authorized users.

Global Assessment of the Activity of Tigecycline against Multidrug-Resistant Gram-Negative Pathogens between 2004 and 2014 as Part of the Tigecycline Evaluation and Surveillance Trial

“…Stone et al (17) reported the development of resistance in vivo after 53 days of tigecycline treatment, and Spanu et al (18) reported resistance after 21 days of treatment. Despite these reports of development of tigecycline resistance among E. coli isolates, the current TEST study shows that tigecycline remains active against the majority of MDR E. coli isolates, and the TEST publication by Hoban et al (12) reported that tigecycline was active against carbapenem-resistant E. coli isolates collected between 2004 and 2013.…”

“…This study describes the activity of tigecycline against MDR Gram-negative isolates collected globally between 2004 and 2014. Isolates collected during the earlier years of the study period have been included in previous TEST publications, including reports focused on MDR A. baumannii (10) and MDR Enterobacteriaceae (11) isolates that were collected in the United States between 2004 and 2006 and on MDR Gram-negative isolates collected globally between 2004 and 2013 (12). …”

Prescription Patterns for Tigecycline in Severely Ill Patients for Non-FDA Approved Indications in a Developing Country: A Compromised Outcome

“…Burkhardt et al showed that tigecycline plasma concentrations reach 0.43 ± 0.19 mg/L at 1 h and 0.36 ± 0.2 mg/L at 4 h after infusion (Burkhardt et al, 2009). These values are lower than MIC 90 of most gram-negative bacteria and some of the gram-positive bacteria (Hoban et al, 2015). …”

“…In these trials, gram-positive species were predominant, including 13% methicillin-resistant S. aureus and 8% vancomycin-sensitive Enterococci . The global MIC 90 of these organisms does not exceed 0.25 mg/L (Hoban et al, 2015); however, that of ESBL-producing E. coli, Klebsiella species, and A. baumannii is ~2 mg/L (Hoban et al, 2015). Based on the poor therapeutic outcome of tigecycline in our study and its low mean peak concentration in the skin (0.56 ± 0.25 mg/L) reported elsewhere (Stein et al, 2011), we suggest that a double dose of tigecycline be used in the treatment of cSSTIs when resistant gram-negative ecology similar to ours is suspected and when there is no other alternative.…”

“…It is well-known that the antibiotic concentration in ELF and ACs is an important indicator for treatment success in lower respiratory tract infections (Mouton et al, 2008). Despite its low tissue concentration, tigecycline has proven activity in cases of CAP in which Streptococcus pneumoniae and other atypical bacteria with low MIC (0.06 mg/L) are suspected (Hoban et al, 2015). However, when other organisms with higher MIC (2 mg/L) are suspected, such as non-lactose fermenting gram-negative rods in patients with pulmonary pathology or in cases of HAP, the use of tigecycline becomes questionable.…”