Dataset Information

Epidemiology of Bloodstream Infections Caused by Escherichia coli and Klebsiella pneumoniae That Are Piperacillin-Tazobactam-Nonsusceptible but Ceftriaxone-Susceptible.

ABSTRACT:

Background

Piperacillin-tazobactam-nonsusceptible (TZP-NS) Enterobacteriaceae are typically also resistant to ceftriaxone. We recently encountered bacteremias due to Escherichia coli (Ec) and Klebsiella pneumoniae (Kp) that were TZP-NS but ceftriaxone-susceptible (CRO-S).

Methods

We reviewed all Ec and Kp bacteremias from 2011 to 2015 at our center and assessed the prevalence, antimicrobial susceptibilities, genetic profiles, patient characteristics, treatments, and outcomes of TZP-NS/CRO-S infections. We identified risk factors for TZP-NS/CRO-S infections compared with Ec and Kp bacteremias that were TZP-S and CRO-S (Control Group 1) and compared outcomes of patients with TZP-NS/CRO-S bacteremias, Control Group 1, and patients bacteremic with extended-spectrum β-lactamase (ESBL)-producing Ec and Kp.

Results

There were 1857 Ec and Kp bacteremia episodes, of which 78 (4.2%) were TZP-NS/CRO-S (Ec: 50/1227 [4.1%]; Kp: 28/630 [4.4%]). All TZP-NS/CRO-S isolates were also ampicillin-sulbactam-NS. Of 32 TZP-NS/CRO-S isolates that were sequenced, 28 (88%) harbored bla _TEM-1 or bla _SHV-1, none had an ESBL or AmpC β-lactamase gene, and many sequence types were represented. Independent risk factors for TZP-NS/CRO-S bacteremia were exposure to β-lactam/β-lactamase inhibitors (BL/BLIs; adjusted odds ratio [aOR], 5.5; P < .001) and cephalosporins (aOR, 3.0; P = .04). Thirty-day mortality after TZP-NS/CRO-S bacteremia was 25%, which was similar to control groups and was similar in patients treated empirically with BL/BLIs compared with those treated with cephalosporins or carbapenems. Targeted therapy with cephalosporins did not yield a higher 30-day mortality rate than carbapenem therapy.

Conclusions

TZP-NS/CRO-S Ec and Kp are emerging causes of bacteremia, and further research is needed to better understand the epidemiology, resistance mechanisms, and clinical impact of these strains.

SUBMITTER: Baker TM

PROVIDER: S-EPMC6290775 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Publications

Epidemiology of Bloodstream Infections Caused by <i>Escherichia coli</i> and <i>Klebsiella pneumoniae</i> That Are Piperacillin-Tazobactam-Nonsusceptible but Ceftriaxone-Susceptible.

Baker Thomas M TM Rogers Wesley W Chavda Kalyan D KD Westblade Lars F LF Jenkins Stephen G SG Nicolau David P DP Kreiswirth Barry N BN Calfee David P DP Satlin Michael J MJ

Open forum infectious diseases 20181119 12

<h4>Background</h4>Piperacillin-tazobactam-nonsusceptible (TZP-NS) Enterobacteriaceae are typically also resistant to ceftriaxone. We recently encountered bacteremias due to <i>Escherichia coli</i> (<i>Ec</i>) and <i>Klebsiella pneumoniae</i> (<i>Kp</i>) that were TZP-NS but ceftriaxone-susceptible (CRO-S).<h4>Methods</h4>We reviewed all <i>Ec</i> and <i>Kp</i> bacteremias from 2011 to 2015 at our center and assessed the prevalence, antimicrobial susceptibilities, genetic profiles, patient chara ...[more]

PMID: 30568979

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