Healthcare-Associated Bloodstream Infections in a Community Hospital

Background: Cases of healthcare-associated infection are expected to increase in number during the next decade, but data on healthcare-associated bloodstream infections are limited in Taiwan. Objectives: To characterize the clinical features, microbiological factors, and outcome among patients with community-acquired bloodstream infection (CAB), hospital-acquired bloodstream infection (HAB) and healthcare-associated bloodstream infection (HCAB). Methods: This 12-month prospective study was conducted at the Erlin branch of Changhua Christian Hospital from January 1, 2005 to December 31, 2005. All admitted patients over 18 years old with microbiologically confirmed bloodstream infections (BSIs) were enrolled. Data were collected on demographics, places before hospitalization, comorbid medical conditions, clinical profile, microorganisms, source of infection, antimicrobial susceptibility testing, empirical antibiotic therapy, and hospital outcome. The prognostic value was determined using the multivariate logistic regression procedure. Results: During the study period, a total of 194 episodes of BSIs were reported; 110 (56.7%) had CAB, 52 (26.8%) had HCAB, and 32 (16.5%) had HAB. Underlying malignancy and neurological disorders with poor performance were more common in patients with HCAB or HAB than in patients with CAB. Patients with HCAB had less frequency of urinary tract and had more intra-vascular catheters as the source of BSI when compared with patients with CAB (both p＜0.001); more uncertain source of BSIs was found in patients with HAB than in those with HCAB (p＜0.01). Gram- negative bacteria were isolated from the blood in 67.3% of episodes of HCAB. Susceptibility test results of Enterobacteriaciae family revealed that resistance to first-, second-, or third-generation cephalosporins were more common in isolates from HCAB and HAB than in isolates from CAB (all p＜0.05). Empirical antibiotic treatment was appropriate in 85% of CAB subgroup, in 79% of HCAB subgroup, and in 66% of HAB subgroup. Mortality rates were 11.8%, 19.3%, and 34.4% in patients with CAB, HCAB, and HAB, respectively. Multivariate analysis revealed the independent predictors of mortality for patients with HCAB to be comorbidity of underlying cancer (OR, 9.8; 95% CI, 1.5-62.1; p=0.015) and presence of severe sepsis or septic shock (OR, 12; 95% CI, 2.1-77.3; p=0.006). Conclusions: Although HCAB patients admitted to the hospital from outpatient setting, patients with HCAB represent a distinct situation in comparison with CAB patients. HCAB deserve to be categorized into the intermediate position between CAB and HAB.