Legionnaires’ disease at a medical center in southern Taiwan

Background/purpose: Legionella pneumophila had been recognized as a pathogen for both healthcare-associated and community-acquired pneumonia. We aimed to evaluate clinical features and outcomes of patients with Legionnaires’ disease at a tertiary medical center in southern Taiwan. Methods: From January 2005 to December 2013, a retrospective study of adult cases of Legionnaires’ disease was conducted in a 1200-bed tertiary hospital. Their medical records were reviewed for further evaluation and analysis. Results: A total of 61 cases of Legionnaires’ disease were identified during the study period. Their mean age was 61.1 years, with male predominance (43, 70.5%). Among them, 30 (49.2%) had healthcare-associated pneumonia (HCAP), 20 (32.8%) had community-acquired pneumonia, and notably 11 (18.0%) were caregivers. Patients with healthcare-associated pneumonia tend to have higher Charlson comorbidity scores than those with community-acquired pneumonia (3.6 ± 2.4 vs. 1.9 ± 1.9, p = 0.008) and caregivers (0.5 ± 0.5, p < 0.001). Six patients died, resulting in an in-hospital mortality rate of 9.8%. Underlying cancer (66.7% vs. 20.0%, p = 0.028) and a higher Charlson comorbidity score (4.7 ± 2.6 vs. 2.2 ± 2.2, p = 0.013) were related to a fatal outcome. Conclusion: L. pneumophila remains an important pathogen for pneumonia acquired from the community or associated with healthcare facility. Healthy caregivers may potentially be at risk for Legionella infection in certain clinical settings.