title: Determination of synergy between sulbactam, meropenem and colistin in carbapenem-resistant Klebsiella pneumoniae and Acinetobacter baumannii isolates and correlation with the molecular mechanism of resistance.
abstract: Treatment of infections with carbapenem-resistant Gram negative organism is a major challenge especially among intensive care patients. Combinations of sulbactam, meropenem and colistin was studied for its synergistic activity against 100 invasive isolates of carbapenem-resistant Klebsiella pneumoniae and Acinetobacter baumannii-calcoaceticus complex by checkerboard assay and time kill assay (TKA). In addition, presence of carbapenemase production was determined by multiplex PCR. Time kill assay detected more synergy than checkerboard assay. Good bactericidal activity of 70-100% was noted with the combinations tested. Among K. pneumoniae, isolates producing NDM carbapenemase alone showed significantly more synergy than isolates producing OXA-48-like carbapenemases. In treatment of infection with carbapenem-resistant organisms, the site of infection and the type of carbapenemase produced may help to determine the most effective combination of antimicrobials.
authors.affiliation: a Department of Microbiology , Christian Medical College , Vellore , Tamil Nadu , India.
authors.forename: Shakti
authors.initials: S
authors.lastname: Laishram
authors.affiliation: a Department of Microbiology , Christian Medical College , Vellore , Tamil Nadu , India.
authors.forename: Shalini
authors.initials: S
authors.lastname: Anandan
authors.affiliation: a Department of Microbiology , Christian Medical College , Vellore , Tamil Nadu , India.
authors.forename: Bakthavatchalam Yamuna
authors.initials: BY
authors.lastname: Devi
authors.affiliation: a Department of Microbiology , Christian Medical College , Vellore , Tamil Nadu , India.
authors.forename: Munusamy
authors.initials: M
authors.lastname: Elakkiya
authors.affiliation: a Department of Microbiology , Christian Medical College , Vellore , Tamil Nadu , India.
authors.forename: Babu
authors.initials: B
authors.lastname: Priyanka
authors.affiliation: a Department of Microbiology , Christian Medical College , Vellore , Tamil Nadu , India.
authors.forename: Thukkaram
authors.initials: T
authors.lastname: Bhuvaneshwari
authors.affiliation: b Medical Intensive Care Unit , Christian Medical College , Vellore , Tamil Nadu , India.
authors.forename: John Victor
authors.initials: JV
authors.lastname: Peter
authors.affiliation: c Surgical Intensive Care Unit , Christian Medical College , , Vellore , Tamil Nadu , India.
authors.forename: Kandasmy
authors.initials: K
authors.lastname: Subramani
authors.affiliation: a Department of Microbiology , Christian Medical College , Vellore , Tamil Nadu , India.
authors.forename: Veeraraghavan
authors.initials: V
authors.lastname: Balaji
mesh_terms: D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D015780:Carbapenems / Q000494:pharmacology*; D003091:Colistin / Q000494:pharmacology; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004357:Drug Synergism; D006801:Humans; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000302:isolation & purification; D000077731:Meropenem; D008826:Microbial Sensitivity Tests; D013407:Sulbactam / Q000494:pharmacology; D013845:Thienamycins / Q000494:pharmacology; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D013845:Thienamycins; D001618:beta-Lactamases; C063912:carbapenemase; D000077731:Meropenem; D013407:Sulbactam; D003091:Colistin
keywords: Acinetobacter baumannii; Carbapenem resistant; Colistin; OXA-48 like; Klebsiella pneumoniae; Meropenem; NDM; Sulbactam; Synergy