[Bacteraemia due to extended-spectrum beta-lactamases (ESBL) and other beta-lactamases (ampC and carbapenemase) producing Enterobacteriaceae: association with health-care and cancer].

Introduction: Bloodstream infections due to multire-sistant Enterobacteriaceae are a major matter of concern nowadays. The present study evaluated the impact of these infections in our area.

Methods: Prospective observational study of a cohort of patients with bacteraemia due to extended-spectrum beta-lactamases (ESBL) and other beta-lactamases producing organisms among hospitalized patients in Cruces Hospital for 2 years. We conducted a descriptive analysis, a subgroup analysis (cancer vs. non-cancer patients) and a mortality analysis.

Results: During the study period, 3409 episodes of bacteraemia were diagnosed, of which 124 (3.6%) were ESBL and other beta-lactamases producing Enterobacteriaceae. 40.3% of the cases were nosocomial, 15.3% community acquired and 44.4% were health-care associated. 44.4% of the cohort had cancer as underlying disease. The most commonly isolated organism was E. coli (83% of cases), regardless of the source of infection. 58.1% of patients received inadequate empirical therapy. 7 day-mortality was 10.5% and 30 day-mortality was 21.8%. None of the analyzed variables showed association with 7 and 14 day-mortality, but the presence of solid cancer (p= 0.032) and advanced HIV infection (p = 0.027), were significantly associated with higher 30 day-mortality.

Conclusions: More than half of bacteraemia episodes affected outpatients and most of them were health-care associated episodes. Even though more than half of the patients received inadequate empirical treatment, this was not related to higher mortality. We only found an association between 30 day-mortality and the presence of underlying solid malignancy or advanced HIV infection.