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Published on: August 30, 2018
Gram-negative bacteraemia in non-ICU patients: factors associated with inadequate antibiotic therapy and impact on
Jonas Marschall1, Denis Agniel, Victoria J Fraser
1Division of Infectious Diseases, Washington University School of Medicine, St Louis, MO, USA. jmarscha@im.wustl.edu
Background:
A considerable number of gram-negative bacteraemias occur outside intensive care units (ICUs). Inadequate antibiotic therapy in ICUs has been associated with adverse outcomes; however, there are no prospective studies in non-ICU patients.
Methods:
A 6 month (1 August 2006-31 January 2007), prospective cohort study of non-ICU patients with gram-negative bacteraemia in a tertiary-care hospital was performed. Inadequate empirical antibiotic therapy was defined as no antibiotic or starting a non-susceptible antibiotic within 24 h after the initial positive blood culture.
Results:
Two hundred and fifty non-ICU patients had gram-negative bacteraemia. The mean age was 56.4 (+/-16.1) years. The predominant bacteria in monomicrobial infections were Escherichia coli (24%), Klebsiella pneumoniae (18%) and Pseudomonas aeruginosa (8%). Sixty-one (24%) patients had polymicrobial bacteraemia. Seventy patients (28%) required ICU transfer and 35 (14%) died. Seventy-nine (31.6%) received inadequate empirical antibiotic therapy. These patients were more likely to have a hospital-acquired infection [odds ratio (OR) = 1.99, 95% confidence interval (CI) = 1.11-3.56, P = 0.02] and less likely to have E. coli monomicrobial bacteraemia [OR 0.40 (95% CI 0.19-0.86), P = 0.02]. There were no differences in occurrence of sepsis [72 (91.1%) patients with inadequate versus 159 (93.0%) with adequate therapy; P = 0.6], ICU transfer [20 (25.3%) versus 50 (29.2%); P = 0.5], post-bacteraemia length of stay (median = 6.8 versus 6.1 days; P = 0.09) or death [11 (13.9%) versus 24 (14.0%); P = 1.0].
Conclusions:
Nearly one-third of the non-ICU patients with gram-negative bacteraemia received inadequate empirical antibiotic therapy. There was no difference in adverse outcomes between patients receiving inadequate or adequate therapy in this study.
Insights
Inadequate antibiotic therapy for gram-negative bacteraemia in non-intensive care unit (ICU) patients was common, affecting nearly one-third of those studied. However, this study found no significant difference in adverse outcomes between patients receiving adequate or inadequate empirical antibiotic therapy.
Area of Science:
- Infectious Diseases
- Clinical Microbiology
- Hospital Epidemiology
Background:
- Gram-negative bacteraemia frequently occurs outside intensive care units (ICUs).
- Previous studies linked inadequate antibiotic therapy in ICUs to adverse outcomes.
- Prospective data on non-ICU patients with gram-negative bacteraemia were lacking.
Purpose of the Study:
- To prospectively evaluate the incidence and outcomes of inadequate empirical antibiotic therapy in non-ICU patients with gram-negative bacteraemia.
Main Methods:
- A 6-month prospective cohort study involving non-ICU patients diagnosed with gram-negative bacteraemia.
- Inadequate empirical antibiotic therapy was defined as no antibiotic or a non-susceptible antibiotic within 24 hours of the first positive blood culture.
- Data collected included patient demographics, infection characteristics, treatment, ICU transfer, and mortality.
Main Results:
- Out of 250 patients, 79 (31.6%) received inadequate empirical antibiotic therapy.
- Inadequate therapy was associated with hospital-acquired infections and less frequently with Escherichia coli monomicrobial bacteraemia.
- No significant differences were observed in sepsis occurrence, ICU transfer, length of stay, or mortality between adequate and inadequate therapy groups.
Conclusions:
- Nearly one-third of non-ICU patients with gram-negative bacteraemia received inadequate empirical antibiotic therapy.
- This study did not find a significant association between inadequate empirical antibiotic therapy and adverse outcomes in non-ICU patients.
- Further research may be needed to explore factors influencing outcomes in this patient population.
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