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Published on: July 7, 2020
Effects of reducing beta-lactam antibiotic pressure on intestinal colonization of antibiotic-resistant gram-negative
Saskia Nijssen1, Ad Fluit, David van de Vijver
1Department of Medical Microbiology, St. Elisabethziekenhuis, Hilvarenbeekse Weg 60, 5022 GC Tilburg, The Netherlands.
Background:
We determined the effects of two antibiotic policies (predominance of either beta-lactam antibiotics or fluroquinolones) on acquisition with third-generation cephalosporin-resistant Enterobacteriaceae (CRE) and fluoroquinolone-resistant CRE (FCRE) in two ICUs, with monitoring of other variables that may influence acquisition.
Methods:
After an 8-month baseline period, units were randomized to a predominant beta-lactam antibiotic regimen (weekly cycling of ceftriaxone, amoxicillin-clavulanic acid and fluroquinolones) or a fluoroquinolone regimen for 3 months, with cross-over for another 3 months. Acquisition of CRE and FCRE was determined by microbiological surveillance.
Results:
During baseline, acquisition rates for CRE and FCRE were 14/1,000 and 2/1,000 patient days at risk, respectively. Cross-transmission of CRE accounted for
Conclusion:
A 35-39% reduction of beta-lactam exposure was not associated with reduced acquisition of CRE, whereas a 243% increase of fluoroquinolone use increased acquisition of FCRE.
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