Clinical Predictors And Outcomes Of Klebsiella Pneumoniae Bacteremia In A Regional Hospital In Hong Kong

Abstract

Introduction: Klebsiella pneumoniae (KP) infection is associated with high morbidity and mortality in different clinical settings. Multi-drug resistance associated with extended spectrum beta-lactamase (ESBL) among KP is endemic worldwide. Our study aims to evaluate the clinical characteristics and outcomes of patients with KP bacteraemia in the critical care and general ward settings. Methods: Adult patients admitted to a regional hospital in Hong Kong from 1 January 2009 to 30 June 2016 (7.5 years) with KP bacteremia were included. Demographics, disease severity, clinical features, microbiological characteristics and outcome were analyzed. Results: Among the 853 patients, 178 (20.9%) required critical care and 176 (20.6%) died within 30 days of hospital admission. 30-day survivors were younger (p < 0.001), had lower disease severity (defined by SOFA score) (p < 0.001), presented with hepatobiliary sepsis (p <0.001) or urosepsis (p < 0.001), less septic shock (p = 0.013) or requirement of invasive organ support (p < 0.001) and received appropriate empirical antibiotics (p < 0.001). Cox regression analysis showed that respiratory tract (HR = 2.99; 95% CI = 2.061-4.337;p = <0.001), gastrointestinal tract (excluding hepatobiliary system) infection (HR = 2.763; 95% CI = 1.761-4.337; p = <0.001), use of mechanical ventilation (HR = 2.202; 95% CI = 1.506-3.221; p = <0.001), medical case (HR = 1.830; 95% CI = 1.253-2.672; p = 0.002), inappropriate empirical antibiotics (HR = 1.716; 95% CI = 1.267-2.324; p = <0.001), female (HR = 1.699, CI = 1.251-2.307, p < 0.001), age >65 (HR = 1.692; 95% CI = 1.160-2.467; p = 0.006) and presence of solid tumor (HR = 1.457; 95% CI = 1.056- 2.009; p = 0.022) were independent risk factors for 30-day mortality. Unexpectedly, presence of diabetes mellitus was associated with a better 30-day survival (p = 0.002). ESBL-producing strains were identified in 102 patients (12.0%). Non-hepatobiliary sepsis, use of systemic steroid within 30 days before positive blood culture, presence of solid tumor and use of central venous catheter independently predicted the occurrence of ESBL KP bacteremia. However, presence of an ESBL strain was not associated with higher 30-day mortality. Conclusions: KP bacteremia is associated with high 30-day mortality. Site of infection, patient’s comorbidities and appropriate use of empirical antibiotics are important predictors of patients’ outcome. Early empirical antibiotics in high-risk groups is warranted.