LAUSR

BACKGROUND Carbapenems are considered the treatment of choice for extended-spectrum β-lactamase (ESBL) or AmpC β-lactamase-producing Enterobacteriaceae bacteremia. Data on the effectiveness of non-intravenous carbapenem-sparing antibiotic options are limited. OBJECTIVE To compare the 30 day-mortality and clinical failures associated with the use of carbapenems vs an alternative non-intravenous antibiotic for the definitive treatment of ESBL/AmpC positive Enterobacteriaceae bacteremia. METHODS A 12-year retrospective study (2004 - 2015) including all patients with bacteremia due to ESBL/AmpC-producing Enterobacteriaceae. Given the lack of randomization of the initial therapies, a propensity score for receiving carbapenems was calculated. RESULTS There were 1115 patients with a first episode of bacteremia due to E. coli or K. pneumoniae, of which 123 were ESBL/Amp C-positive (11%). There were 101 eligible patients: 59 in the carbapenem group and 42 in the alternative treatment group (cotrimoxazole 59.5%, quinolones 21.4%). The most frequent sources of infection were urinary (63%) and biliary (15%). Compared to the carbapenem group, patients treated with the alternative regimen had a shorter hospital stay (median [IQR]: 7 days [5-10] vs 12 days [9-18], p<0,001). The use of an alternative non-IV treatment did not increase mortality (OR 0.27; 95% CI 0.05-1.61; p=.15). After controlling for confounding factors with the propensity score, the adjusted OR of carbapenem treatment was 4.95; 95% CI (0.94-26.01, p=.059). CONCLUSION Alternative non-IV carbapenem-sparing antibiotics could have a role in the definitive treatment of ESBL/AmpC-positive Enterobacteriaceae bloodstream infections, allowing a reduction in carbapenem use. The use of cotrimoxazole in our serie has shown favourable results.