title: Quinolone-resistant Haemophilus influenzae in a long-term care facility: clinical and molecular epidemiology.
abstract: We describe a clonal outbreak of quinolone-resistant Haemophilus influenzae (QRHI) from an affiliated long-term care facility (LTCF-A); the outbreak was associated with the clinical use of levofloxacin, which was determined to be a risk factor for acquisition of QRHI. The minimum inhibitory concentration to which 90% of isolates were susceptible (MIC90), as determined by broth microdilution, was >4 microg/mL for levofloxacin, >2 microg/mL for moxifloxacin, >2 microg/mL for gatifloxacin, and 8 microg/mL for gemifloxacin. The MIC90, as determined by Etest (AB Biodisk), was >32 microg/mL for levofloxacin, ciprofloxacin, moxifloxacin, and gatifloxacin. Having been a resident at LTCF-A and having chronic obstructive pulmonary disease were significant risk factors for acquisition of QRHI at our 500-bed hospital (New York Hospital Queens). All QRHI isolates were found to be genetically related by pulsed-field gel electrophoresis, were nontypeable, were susceptible to ceftriaxone and azithromycin, and were negative for beta -lactamase production. Emphasis on patient contact and respiratory isolation and placing colonized or infected patients in cohorts yielded a marked reduction in the prevalence of QRHI at LTCF-A.
authors.affiliation: Infectious Disease Section, New York Hospital Queens, Flushing, New York 11355, USA.
authors.forename: Jawad
authors.initials: J
authors.lastname: Nazir
authors.forename: Carl
authors.initials: C
authors.lastname: Urban
authors.forename: Noriel
authors.initials: N
authors.lastname: Mariano
authors.forename: Janice
authors.initials: J
authors.lastname: Burns
authors.forename: Barbara
authors.initials: B
authors.lastname: Tommasulo
authors.forename: Carl
authors.initials: C
authors.lastname: Rosenberg
authors.forename: Sorana
authors.initials: S
authors.lastname: Segal-Maurer
authors.forename: James J
authors.initials: JJ
authors.lastname: Rahal
mesh_terms: D000367:Age Factors; D000890:Anti-Infective Agents / Q000378:metabolism / Q000627:therapeutic use; D016022:Case-Control Studies; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods / Q000706:statistics & numerical data; D005260:Female; D006192:Haemophilus Infections / Q000453:epidemiology* / Q000235:genetics* / Q000517:prevention & control / Q000635:transmission; D006193:Haemophilus influenzae / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D017053:Infection Control / Q000379:methods / Q000706:statistics & numerical data; D020128:Inhibitory Concentration 50; D064704:Levofloxacin; D008134:Long-Term Care / Q000639:trends*; D008297:Male; D008826:Microbial Sensitivity Tests / Q000379:methods / Q000706:statistics & numerical data; D017720:Molecular Epidemiology / Q000379:methods*; D015999:Multivariate Analysis; D015242:Ofloxacin / Q000378:metabolism* / Q000627:therapeutic use; D012737:Sex Factors
chemical_list: D000890:Anti-Infective Agents; D004269:DNA, Bacterial; D064704:Levofloxacin; D015242:Ofloxacin