title: Bacteremia due to Klebsiella pneumoniae isolates producing the TEM-52 extended-spectrum beta-lactamase: treatment outcome of patients receiving imipenem or ciprofloxacin.
abstract: The treatment outcome of 35 cases of bacteremia due to Klebsiella pneumoniae isolates producing TEM-52 extended-spectrum beta-lactamase was studied. Twenty-eight cases, classified as "nonfatal disease" using the McCabe and Jackson classification, were investigated with regard to ciprofloxacin and imipenem response. Because ciprofloxacin was active in vitro against 21 of 28 isolates, only the treatment outcome of the ciprofloxacin-susceptible subgroup was evaluated. Eight of 10 cases occurred in patients who experienced a complete response to imipenem; 2 of 10 failed to respond. In contrast, only 2 of 7 cases had a partial response to ciprofloxacin, and, in 5 of 7 cases, the treatment failed. Statistical analysis revealed a significant difference in the treatment outcome of the 2 groups (P=.03). Because the isolates had minimum inhibitory concentrations of ciprofloxacin close to the susceptibility breakpoint, treatment failure could be ascribed to the inability of the drug to reach therapeutic concentrations at infected sites.
authors.affiliation: Laboratorio di Microbiologia, Ospedale di Circolo and Università dell'Insubria, Varese, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Endimiani
authors.forename: Francesco
authors.initials: F
authors.lastname: Luzzaro
authors.forename: Mariagrazia
authors.initials: M
authors.lastname: Perilli
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Lombardi
authors.forename: Alessandra
authors.initials: A
authors.lastname: Colì
authors.forename: Antonio
authors.initials: A
authors.lastname: Tamborini
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Amicosante
authors.forename: Antonio
authors.initials: A
authors.lastname: Toniolo
mesh_terms: D016470:Bacteremia / Q000188:drug therapy*; D002939:Ciprofloxacin / Q000627:therapeutic use*; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D015378:Imipenem / Q000627:therapeutic use*; D007710:Klebsiella Infections / Q000188:drug therapy*; D007711:Klebsiella pneumoniae; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D016896:Treatment Outcome; D001618:beta-Lactamases / Q000032:analysis* / Q000235:genetics
chemical_list: D002939:Ciprofloxacin; D015378:Imipenem; C445691:TEM-52 beta-lactamase; D001618:beta-Lactamases