The etiology and bacteriology of healthcare-associated empyema are quite different from those of community-acquired empyema

Abstract

Objects: Changes in patients' background and life environment could contribute to increase healthcare-associated (HCA) empyema. There are no guidelines and statements for HCA empyema.

Methods: We retrospectively reviewed all patients with empyema who were admitted to the Aichi Medical University Hospital, Japan between 2008 and 2015. We evaluated patients' characteristics, microbial profiles, treatment and outcomes, and analyzed prognostic factors for 90-day mortality.

Results: A total of 48 patients were enrolled in this study. They were categorized into community-acquired (CA) empyema (16 patients) and healthcare-associated (HCA) empyema (32 patients). HCA empyema patients had higher Charlson comorbidity index (CCI) scores, and poorer performance status (PS) than CA empyema patients. Potentially-drug resistant (PDR) pathogens were seen more frequently in HCA empyema than in CA empyema. Compared with survival and death groups, the death group showed higher CCI scores and poorer PSs than the survival group. The death group had more malignancy than the survival group. PDR pathogens were detected more frequently in the death group than in the survival group. Multivariate analysis showed that emergence of PDR pathogens and malignancies were independent poor prognostic factors for 90-days mortality among empyema.

Conclusion: The etiology and bacteriology of HCA empyema are quite different from those of CA empyema. Especially, the mortality of HCA empyema was higher than the one of CA empyema. Emergence of PDR pathogens in the pleural fluid detected by culture, pulmonary disease and malignancies were independent poor prognostic factors among CA and HCA empyema by multivariate logistic regression analysis.

Keywords: Empyema; Healthcare-associated infection; Parapneumonic effusion; Pleural infection.