Patients with community-acquired bacteremia of unknown origin: clinical characteristics and usefulness of microbiological results for therapeutic issues: a single-center cohort study

Abstract

Bacteremia of unknown origin (BUO) are associated with increased mortality compared to those with identified sources. Microbiological data of those patients could help to characterize an appropriate empirical antibiotic treatment before bloodcultures results are available during sepsis of unknown origin. Based on the dashboard of our ward that prospectively records several parameters from each hospitalization, we report 101 community-acquired BUO selected among 1989 bacteremic patients from July 2005 to April 2016, BUO being defined by the absence of clinical and paraclinical infectious focus and no other microbiological samples retrieving the bacteria isolated from blood cultures. The in-hospital mortality rate was 9%. We retrospectively tested two antibiotic associations: amoxicillin–clavulanic acid + gentamicin (AMC/GM) and 3rd generation cephalosporin + gentamicin (3GC/GM) considered as active if the causative bacteria was susceptible to at least one of the two drugs. The mean age was 71 years with 67% of male, 31 (31%) were immunocompromised and 52 (51%) had severe sepsis. Eleven patients had polymicrobial infections. The leading bacterial species involved were Escherichia coli 25/115 (22%), group D Streptococci 12/115 (10%), viridans Streptococci 12/115 (10%) and Staphylococcus aureus 11/115 (9%). AMC/GM displayed a higher rate of effectiveness compared to 3GC/GM: 100/101 (99%) vs 94/101 (93%) (p = 0.04): one Enterococcus faecium strain impaired the first association, Bacteroides spp. and Enterococcus spp. the second. In case of community-acquired sepsis of unknown origin, AMC + GM should be considered.

Antimicrobial resistance of bacteraemia in the emergency department of a German university hospital (2013–2018): potential carbapenem-sparing empiric treatment options in light of the new EUCAST recommendations

“…Consistent with previously published data [28], Enterobacterales were the most commonly isolated pathogens in cases of true bacteraemia ( n = 439, 59.3%) followed by Staphylococcus aureus ( n = 92, 12.4%). Streptococcus species accounted for 13.5% of true bacteraemia with Streptococcus pneumoniae ( n = 19) being the most frequently isolated, followed by Streptococcus pyogenes ( n = 16).…”

Risk Factors for the Acquisition of Enterococcus faecium Infection and Mortality in Patients with Enterococcal Bacteremia: A 5-Year Retrospective Analysis in a Tertiary Care University Hospital

“…However, corticosteroids not only decrease inflammation but also have side effects, including a reduction in the activity of the immune system, as well as hyperglycemia. A previous study reported that an unknown focus of bacteremia was associated with inappropriate antibiotic therapy and poor clinical outcome [ 36 ]. These findings suggest that the risk factors associated with mortality provide useful information for clinicians to avoid treatment failure, thereby enabling appropriate medical therapy after the onset of bacteremia.…”

Clinical Characteristics and Risk Factors for Mortality due to Bloodstream Infection of Unknown Origin in Hemodialysis Patients: A Single-Center, Retrospective Study

“…Hospital-acquired BSI was defined as the bacteremia and fungemia that occurred after 48 h of admission. BSI was defined when no focus of infection could be specified with medical history, physical examination, clinical data, microbiological tests, and imaging [10, 12]. Owing to the retrospective nature of the study, the consent of patients was not required.…”

“…However, independent risk factors for BSI-associated mortality, especially in case of BSI of unknown origin, remain uncertain. BSIs of unknown origin are prevalent in HD patients and are associated with high mortality as compared to those with identified origin of infection [10]. Therefore, it is important to detect the origin of BSI.…”