Association of levofloxacin resistance with mortality in adult patients with invasive pneumococcal diseases: a post hoc analysis of a prospective cohort

Objective This study was conducted to identify risk factors for mortality and to evaluate the impact of antimicrobial resistance on outcome in adult patients with invasive pneumococcal disease (IPD). Methods A post hoc analysis of an observational cohort study on community-acquired pneumococcal infections was conducted and a total of 136 adult patients with IPD were analyzed in this study. Results Pneumonia was the most common type of infection (n = 84, 61.8 %), followed by primary bacteremia (n = 15, 11.0 %) and meningitis (n = 15, 11.0 %). One hundred and three patients (75.7 %) had concomitant pneumococcal bacteremia. The overall 30-day mortality rate was 26.5 % (36/136), and factors associated with 30-day mortality were corticosteroid use, presentation with septic shock, and development of acute respiratory distress syndrome (ARDS) (all P < 0.05). While penicillin and erythromycin resistance were associated with a lower mortality, an association between levofloxacin resistance and increased mortality was found in the univariate analysis; however, statistical significance was not reached (P = 0.083). Multivariable analysis showed that presentation with septic shock, corticosteroid use, development of ARDS, and levofloxacin resistance were independent factors associated with 30-day mortality. Of the five patients with IPD caused by levofloxacin-resistant Streptococcus pneumoniae, three (60 %) died within 30 days of diagnosis. Conclusion Levofloxacin resistance was associated with increased mortality, along with septic shock, prior use of corticosteroids, and development of ARDS, in adult patients with IPD. Our data suggest that the emergence of levofloxacin resistance among invasive pneumococcal isolates is now becoming a challenge for clinicians managing community-acquired bacterial infections.