title: Susceptibility of important Gram-negative pathogens to tigecycline and other antibiotics in Latin America between 2004 and 2010.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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 Escherichia coli. Susceptibility to amikacin was also >95% for non-ESBL E. coli. 24.3% of E. coli were ESBL producers, ranging from 11.2% (58/519) in Colombia to 40.3% (31/77) in Honduras. Greater than 90% of non-ESBL Klebsiella pneumoniae were susceptible to tigecycline, carbapenems and amikacin. 35.3% of K. pneumoniae 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 Klebsiella oxytoca, Enterobacter spp., and Serratia marcescens were susceptible to amikacin, carbapenems and tigecycline. The highest rates of susceptibility against Acinetobacter baumannii were seen for minocycline (89.4%) and imipenem (62.5%), while 95.8% of the A. baumannii isolates displayed an MIC≤2 μg/mL for tigecycline.
  
  
  CONCLUSIONS
  In this study carbapenems and tigecycline remain active against Enterobacteriaceae and A. baumannii; however, there is cause for concern with carbapenem non-susceptible isolates reported in all countries included in this study.
authors.affiliation: Laboratorio de Microbiología, Hospital Aleman, Pueyrredón 1640, PB, Ciudad Autónoma de Buenos Aires, Argentina. lfcanigia@labdl.com.ar
authors.forename: Liliana
authors.initials: L
authors.lastname: Fernández-Canigia
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Dowzicky
mesh_terms: D040981:Acinetobacter baumannii / Q000187:drug effects / Q000302:isolation & purification; D000583:Amikacin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology; D024901:Drug Resistance, Multiple, Bacterial; D004754:Enterobacter / Q000187:drug effects / Q000302:isolation & purification; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism; D015378:Imipenem / Q000494:pharmacology; D041121:Klebsiella oxytoca / Q000187:drug effects / Q000302:isolation & purification; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000302:isolation & purification; D007843:Latin America; D000077731:Meropenem; D008826:Microbial Sensitivity Tests; D008911:Minocycline / Q000031:analogs & derivatives* / Q000494:pharmacology; D012706:Serratia marcescens / Q000187:drug effects / Q000302:isolation & purification; D013845:Thienamycins / Q000494:pharmacology; D000078304:Tigecycline; D014481:United States; D014486:United States Food and Drug Administration; D001618:beta-Lactamases / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D013845:Thienamycins; D000078304:Tigecycline; D015378:Imipenem; D000583:Amikacin; D001618:beta-Lactamases; D000077731:Meropenem; D008911:Minocycline