Longitudinal Assessment of Antimicrobial Susceptibility among Gram-Negative and Gram-Positive Organisms Collected from Italy as Part of the Tigecycline Evaluation and Surveillance Trial between 2004 and 2011

The Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) was initiated in 2004 to longitudinally monitor the activity of the broad-spectrum glycylcycline antimicrobial tigecycline, and a suite of comparator agents, against an array of clinically important bacterial pathogens worldwide. In this report, we examine the activity of tigecycline and comparators against a collection of 13,245 clinical isolates, both Gram-positive (n = 4,078 and Gram-negative (n = 9,167), collected from 27 centres in Italy between 2004 and 2011. Susceptibility was established according to Clinical Laboratory Standards Institute guidelines. Tigecycline and linezolid exhibited very good activity against Gram-positive pathogens, with MIC90s ranging from 0.06 to 0.25 mg/L and 1–4 mg/L, respectively; vancomycin and the carbapenems also showed good activity against select Gram-positive pathogens. Tigecycline was the most active agent against Gram-negative pathogens (except P. aeruginosa), with MIC90s ranging from 0.25–2 mg/L (16 mg/L for P. aeruginosa). Amikacin and the carbapenems also possessed good activity against many Gram-negative pathogens here. ESBL-positive E. coli increased in prevalence from 2004 to 2011, while ESBL-positive Klebsiella spp., vancomycin-resistant enterococci and MRSA decreased in prevalence. Linezolid, tigecycline and vancomycin susceptibility were very stable over the course of this study, while susceptibility to ampicillin, piperacillin-tazobactam, ceftriaxone and levofloxacin varied over time according to pathogen; minocycline and cefepime susceptibility among several pathogens decreased during this study

Assessment of the Activity of Tigecycline against Gram-Positive and Gram-Negative Organisms Collected from Italy between 2012 and 2014, as Part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.)

As part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T) we report the in vitro activity of tigecycline and its comparators against Gram-negative and Gram-positive organisms collected from Italian centers between 2012 and 2014. Minimum inhibitory concentrations were determined according to the broth microdilution methodology of the Clinical and Laboratory Standards Institute, and antimicrobial resistance was determined using the European Committee on Antimicrobial Susceptibility Testing interpretive criteria. Among the Enterobacteriaceae, 31% of Escherichia coli isolates, 22% of Klebsiella pneumoniae, and 1% of Klebsiella oxytoca were extended-spectrum β-lactamase producers (ESBLs). Resistance rates among ESBL-K. pneumoniae and ESBL-E. coli to meropenem were 24% and <1%, respectively. Thirty-seven percent of K. pneumoniae were multidrug resistant (MDR) strains. Resistance rates among isolates of Acinetobacter baumannii to amikacin, levofloxacin and meropenem were between 84% and 94%. Eighty percent of A. baumannii isolates were MDR strains. Methicillin-resistant Staphylococcus aureus (MRSA) accounted for 38% of S. aureus isolates. No isolates of MRSA were resistant to linezolid, tigecycline or vancomycin. Antimicrobial resistance remains a problem in Italy with increasing numbers of MDR organisms. Despite high levels, MRSA rates appear to be stabilising. Tigecycline retains its in vitro activity against the majority of organisms, including those with multidrug resistance

Antimicrobial susceptibility among Gram-positive and Gram-negative organisms collected from the Latin American region between 2004 and 2015 as part of the Tigecycline Evaluation and Surveillance Trial

Abstract Background The in vitro activity of tigecycline and comparator agents was evaluated against Gram-positive and Gram-negative isolates collected in Latin American centers between 2004 and 2015 as part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) global surveillance study. Methods Minimum inhibitory concentrations (MICs) were determined using the broth microdilution methodology according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Antimicrobial susceptibility was determined using CLSI breakpoints, except for tigecycline for which the US Food and Drugs Administration breakpoints were used. Results A total of 48.3% (2202/4563) of Staphylococcus aureus isolates were methicillin-resistant S. aureus (MRSA). All MRSA isolates were susceptible to linezolid and vancomycin, and 99.9% (2199/2202) were susceptible to tigecycline. Among Streptococcus pneumoniae isolates, 13.8% (198/1436) were penicillin-resistant; all were susceptible to linezolid and vancomycin, and 98.0% (194/198) were susceptible to tigecycline. Susceptibility was >99.0% for linezolid and tigecycline against Enterococcus faecium and Enterococcus faecalis isolates. A total of 40.8% (235/576) E. faecium and 1.6% (33/2004) E. faecalis isolates were vancomycin-resistant. Among the Enterobacteriaceae, 36.3% (1465/4032) of Klebsiella pneumoniae isolates, 16.4% (67/409) of Klebsiella oxytoca isolates and 25.4% (1246/4912) of Escherichia coli isolates were extended-spectrum β-lactamase (ESBL) producers. Of the ESBL-producing K. pneumoniae and E. coli isolates, susceptibility was highest to tigecycline [93.4% (1369/1465) and 99.8% (1244/1246), respectively] and meropenem [86.9% (1103/1270) and 97.0% (1070/1103), respectively]. A total of 26.7% (966/3613) of Pseudomonas aeruginosa isolates were multidrug-resistant (MDR). Among all P. aeruginosa isolates, susceptibility was highest to amikacin [72.8% (2632/3613)]. A total of 70.3% (1654/2354) of Acinetobacter baumannii isolates were MDR, and susceptibility was highest to minocycline [88.3% (2079/2354) for all isolates, 86.2% (1426/1654) for MDR isolates]. Tigecycline had the lowest MIC90 (2 mg/L) among A. baumannii isolates, including MDR isolates. Conclusions This study of isolates from Latin America shows that linezolid, vancomycin and tigecycline continue to be active in vitro against important Gram-positive organisms such as MRSA, and that susceptibility rates to meropenem and tigecycline against members of the Enterobacteriaceae, including ESBL-producers, were high. However, we report that Latin America has high rates of MRSA, MDR A. baumannii and ESBL-producing Enterobacteriaceae which require continued monitoring

Antimicrobial susceptibility among gram-negative isolates collected from intensive care units in north america, europe, the Asia-pacific rim, latin america, the middle East, and Africa between 2004 and 2009 as part of the tigecycline evaluation and surveillance trial.

International audienceBACKGROUND: The Tigecycline Evaluation and Surveillance Trial is an antimicrobial susceptibility surveillance program that collects gram-positive and gram-negative organisms globally. OBJECTIVE: This analysis reports on antimicrobial susceptibility among 23,918 gram-negative isolates collected from intensive care units globally between 2004 and 2009. METHODS: MICs and susceptibility were determined according to the guidelines of the Clinical and Laboratory Standards Institute (US Food and Drug Administration breakpoints were applied against tigecycline). RESULTS: Gram-negative isolates were collected from 6 geographical regions: North America, 8099 isolates; Europe, 9244; Asia-Pacific Rim, 1573; Latin America, 3996; the Middle East, 635; and Africa, 371. North America reported the lowest rates of extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli both overall (12.8% and 4.7%, respectively) and in each year of collection. High rates of ESBL production were reported among K pneumoniae from Latin America (45.5%) and Africa (54.9%) and for E coli from the Middle East (32.4%). Imipenem and tigecycline maintained >90% susceptibility against K pneumoniae, E coli, Klebsiella oxytoca, Enterobacter cloacae, and Serratia marcescens for all regions. Susceptibility to meropenem was >90% against all K oxytoca and S marcescens. Large regional variations in susceptibility among Acinetobacter baumannii were reported, with the largest variations reported for amikacin (75.2% in North America, 21.8% in the Middle East) and meropenem (60.4% in North America, 15.9% in Africa). MIC(90) values for tigecycline against A baumannii were low (1-2 mg/L) for all regions. Against P aeruginosa, susceptibility to amikacin (97.5% in North America, 67.5% in Latin America) and meropenem (79.1% in North America, 51.4% in Africa) had the largest variations. CONCLUSIONS: Antimicrobial resistance among gram-negative intensive care unit isolates was highly variable between geographic regions. The carbapenems were active in vitro against Enterobacteriaceae, A baumannii and P aeruginosa, and tigecycline continued to be active in vitro against members of the Enterobacteriaceae and A baumannii collected from intensive care units in North America, Europe, the Asia-Pacific Rim, Latin America, the Middle East, and Africa

Susceptibility of important Gram-negative pathogens to tigecycline and other antibiotics in Latin America between 2004 and 2010

<p>Abstract</p> <p>Background</p> <p>The Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) is a global surveillance study of antimicrobial susceptibility. This study reports data from Gram-negative isolates collected from centers in Latin America between 2004 and 2010.</p> <p>Methods</p> <p>Consecutive bacterial isolates were tested at each center using broth microdilution methodology as described by the Clinical Laboratory Standards Institute (CLSI). Susceptibility was determined using the CLSI interpretive criteria. For tigecycline the US Federal Drug Administration (FDA) criteria were used.</p> <p>Results</p> <p>A total of 16 232 isolates were analyzed. Susceptibility to imipenem, meropenem, and tigecycline was >95% against both non-extended-spectrum β-lactamase (ESBL) and ESBL producing <it>Escherichia coli</it>. Susceptibility to amikacin was also >95% for non-ESBL <it>E. coli</it>. 24.3% of <it>E. coli</it> were ESBL producers, ranging from 11.2% (58/519) in Colombia to 40.3% (31/77) in Honduras. Greater than 90% of non-ESBL <it>Klebsiella pneumoniae</it> were susceptible to tigecycline, carbapenems and amikacin. 35.3% of <it>K. pneumoniae</it> were ESBL producers, ranging from 17.2% (36/209) in Venezuela to 73.3% (55/75) in Honduras, with only imipenem and tigecycline maintaining >90% susceptibility. Greater than 90% of <it>Klebsiella oxytoca</it>, <it>Enterobacter</it> spp., and <it>Serratia marcescens</it> were susceptible to amikacin, carbapenems and tigecycline. The highest rates of susceptibility against <it>Acinetobacter baumannii</it> were seen for minocycline (89.4%) and imipenem (62.5%), while 95.8% of the <it>A. baumannii</it> isolates displayed an MIC ≤2 μg/mL for tigecycline.</p> <p>Conclusions</p> <p>In this study carbapenems and tigecycline remain active against Enterobacteriaceae and <it>A. baumannii</it>; however, there is cause for concern with carbapenem non-susceptible isolates reported in all countries included in this study.</p

Antimicrobial activity against a global collection of skin and skin structure pathogens: results from the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.), 2010–2014

Background: As part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) we report antimicrobial resistance among Gram-positive and Gram-negative isolates collected globally from integumentary sources between 2010 and 2014. Methods: Minimum inhibitory concentrations and antimicrobial resistance were determined according to Clinical and Laboratory Standards Institute guidelines (US Food and Drug Administration breakpoints against tigecycline). The Cochran–Armitage trend test was used to identify statistically significant changes in resistance. Results: Global rates of methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Acinetobacter baumannii were 38% and 43%, respectively. No S. aureus isolates were resistant to linezolid or vancomycin; all isolates were susceptible to tigecycline. Two percent of Enterococcus faecalis and 28% of Enterococcus faecium were vancomycin-resistant. Extended-spectrum β-lactamase (ESBL) producers accounted for 22% of Klebsiella pneumoniae and 16% of Escherichia coli. Resistance to minocycline among E. faecalis, E. faecium, K. pneumoniae, and E. coli decreased significantly (p < 0.0001). There were significant increases (p < 0.0001) in A. baumannii resistance to cefepime, ceftazidime, ceftriaxone, levofloxacin, meropenem, and piperacillin–tazobactam. Conclusions: Among isolates from integumentary sources, rates of MRSA and ESBL-producing Enterobacteriaceae are stabilizing. Carbapenems and tigecycline have retained their in vitro activity against Gram-positive and Gram-negative organisms. Few agents were active against A. baumannii; its increasing resistance is cause for concern

In vitro activity of tigecycline and comparators (2014-2016) among key WHO 'priority pathogens' and longitudinal assessment (2004-2016) of antimicrobial resistance: a report from the TEST study

We report contemporary (2014-2016) Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) global data on activity of tigecycline and comparators against WHO 'priority pathogens', and global trends (2004-2016) in antimicrobial resistance. MICs were determined using CLSI broth microdilution methodology. Antimicrobial resistance was determined using CLSI breakpoints (FDA breakpoints for tigecycline). Data are reported for Africa, Asia, Europe, North America and South America. From 2014-2016, Africa, Asia and South America reported highest resistance rates among Acinetobacter baumannii; North America lowest (all antimicrobials tested). The tigecycline MIC90 against A. baumannii was 2 mg/L in all regions except South America (1 mg/L). Among Enterobacteriaceae, meropenem resistance was low and tigecycline resistance was <= 1.3% in all regions (Escherichia coli, 0.0-0.3%; Klebsiella pneumoniae 0.0-1.3%; Enterobacter spp. 0.5-1.1%; Serratia marcescens 0.0-1.3%). Ceftriaxone resistance among E. coli ranged from 14.5% (North America) to 54.7% (Asia), and among K. pneumoniae from 9.1% (North America) to 54.0% (South America). North America reported highest rates of vancomycin-resistant Enterococcus faecium (64.6%); Europe lowest (17.7%). The tigecycline MIC90 against methicillin-resistant Staphylococcus aureus (MRSA) ranged from 0.12 mg/L (Africa and North America) to 0.5 mg/L (Asia). From 2004-2016, carbapenem resistance increased among A. baumannii (all regions), reaching 92.3% in Africa and 85.7% in South America (2016). Rates of ceftriaxone-resistant E. coli increased in all regions except Asia. Ceftriaxone resistance in K. pneumoniae increased in Europe. Rates of vancomycin-resistant E. faecium and MRSA were highest in North America and South America (and Asia for MRSA); lowest in Europe. (C) 2018 Elsevier B.V. and International Society of Chemotherapy. All rights reserved

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

CITATION: Kanj, S., Whitelaw, A. & Dowzicky, M.J. 2014. 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. International Journal of Antimicrobial Agents, 43(2): 170–178, doi: 10.1016/j.ijantimicag.2013.10.011.The original publication is available at http://www.ijaaonline.comThe 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 2 mg/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.http://www.ijaaonline.com/article/S0924-8579(13)00375-0/abstractPost print versio