title: Emergence of levofloxacin-resistant pneumococci in immunocompromised adults after therapy for community-acquired pneumonia.
abstract: We describe 4 patients infected with levofloxacin-resistant pneumococci after therapy for community-acquired pneumonia (CAP). The 4 patients had 15 episodes of CAP; Streptococcus pneumoniae was isolated from blood or sputum samples obtained during 14 of the episodes. The underlying medical condition was Bruton agammaglobulinemia in 3 patients and chronic lymphoid leukemia in the other. The initial episode of CAP in each patient was due to a levofloxacin-susceptible strain. One of 4 reinfections and 5 of 6 relapses were due to levofloxacin-resistant strains. All of these strains had amino acid substitutions in the quinolone-resistance-determining region of the genes parC and gyrA. The time between episodes of pneumonia varied from 1 to 4 months. In immunocompromised patients with suspected or proven pneumococcal infection, it may be prudent not to use fluoroquinolone monotherapy empirically when the patient has a history of fluoroquinolone therapy in at least the past 4 months.
authors.affiliation: Summa Health System, Akron, Ohio 44304, USA.
authors.forename: Kevin B
authors.initials: KB
authors.lastname: Anderson
authors.forename: James S
authors.initials: JS
authors.lastname: Tan
authors.forename: Thomas M
authors.initials: TM
authors.lastname: File
authors.forename: Joseph R
authors.initials: JR
authors.lastname: DiPersio
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Willey
authors.forename: Donald E
authors.initials: DE
authors.lastname: Low
mesh_terms: D000328:Adult; D000890:Anti-Infective Agents / Q000627:therapeutic use*; D017714:Community-Acquired Infections / Q000188:drug therapy; D004352:Drug Resistance, Microbial; D006801:Humans; D016867:Immunocompromised Host; D064704:Levofloxacin; D008297:Male; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin / Q000627:therapeutic use*; D011008:Pneumococcal Infections / Q000188:drug therapy*; D011018:Pneumonia, Pneumococcal / Q000188:drug therapy*; D013296:Streptococcus pneumoniae / Q000187:drug effects
chemical_list: D000890:Anti-Infective Agents; D064704:Levofloxacin; D015242:Ofloxacin