title: Decreased ceftriaxone susceptibility in emerging (35B and 6C) and persisting (19A) Streptococcus pneumoniae serotypes in the United States, 2011-2012: ceftaroline remains active in vitro among β-lactam agents.
abstract: Totals of 8.7% (103/1,190) and 21.0% (249/1,190) of the Streptococcus pneumoniae isolates recovered from specimens collected in the United States during the 2011-2012 AWARE (Assessing Worldwide Antimicrobial Resistance Evaluation) Surveillance Program were ceftriaxone nonsusceptible according to the CLSI (≤ 1 μg/ml for susceptible) and EUCAST (≤ 0.5 μg/ml for susceptible) criteria, respectively. Decreased susceptibility to ceftriaxone (MIC, 1 μg/ml) was frequently observed among serotypes 19 A (51.4%; 128/249) and 35 B (29.7%; 74/249), which were most often observed in the East South Central and South Atlantic U.S. Census regions. Ceftaroline (MIC50/90, 0.12/0.25 μg/ml) remained active (≥ 96.8% susceptible) when tested against these less susceptible isolates.
authors.affiliation: JMI Laboratories, North Liberty, Iowa, USA rodrigo-mendes@jmilabs.com.
authors.forename: Rodrigo E
authors.initials: RE
authors.lastname: Mendes
authors.affiliation: Cerexa, Inc., Oakland, California, USA.
authors.forename: Donald
authors.initials: D
authors.lastname: Biek
authors.affiliation: Cerexa, Inc., Oakland, California, USA.
authors.forename: Ian A
authors.initials: IA
authors.lastname: Critchley
authors.affiliation: JMI Laboratories, North Liberty, Iowa, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Farrell
authors.affiliation: JMI Laboratories, North Liberty, Iowa, USA.
authors.forename: Helio S
authors.initials: HS
authors.lastname: Sader
authors.affiliation: JMI Laboratories, North Liberty, Iowa, USA.
authors.forename: Ronald N
authors.initials: RN
authors.lastname: Jones
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002443:Ceftriaxone / Q000494:pharmacology*; D002511:Cephalosporins / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D011008:Pneumococcal Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D065288:Serogroup; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification; D014481:United States / Q000453:epidemiology; D018440:beta-Lactam Resistance; D000097583:Ceftaroline
chemical_list: D000900:Anti-Bacterial Agents; D002443:Ceftriaxone; D002511:Cephalosporins; D000097583:Ceftaroline