Risk factors for acquisition of levofloxacin-resistant Streptococcus pneumoniae: A case-control study

A case-control study was conducted to identify the risk factors associated with levofloxacin-resistant Streptococcus pneumoniae (LRSP) colonization or infection. Twenty-seven case patients (patients with LRSP) were compared w ith 54 controls (patients with levofloxacin-susceptible S. pneumoniae). Ris k factors that were significantly associated with LRSP colonization or infe ction, according to univariate analysis, included an older age (median age, 75 years for case patients versus 72.5 years for controls), residence in a nursing home (odds ratio [OR], 7.2), history of recent (OR, 4.6) and multi ple (OR, 4.4) hospitalizations, prior exposure to fluoroquinolones (OR, 10. 6) and beta -lactams (OR, 8.6), presence of chronic obstructive pulmonary d isease (COPD; OR, 5.9), and nosocomial origin of the bacteria (OR, 5.7). Mu ltivariate analysis showed that presence of COPD (OR, 10.3), nosocomial ori gin of the bacteria (OR, 16.2), residence in a nursing home (OR, 7.4), and exposure to fluoroquinolones (OR, 10.7) were independently associated with LRSP colonization or infection. Thus, a distinct group of patients with COP D is the reservoir of LRSP.