Dataset Information

Treatment of Piperacillin-Tazobactam–Nonsusceptible/Ceftriaxone-Susceptible Infections With Carbapenem Versus Carbapenem-Sparing Antimicrobials

ABSTRACT: Abstract

Background

Escherichia coli and Klebsiella pneumoniae with a piperacillin-tazobactam–nonsusceptible/ceftriaxone-susceptible (TZP-NS/CRO-S) phenotype have been increasingly identified, with limited available literature evaluating treatment strategies.

Methods

This was a retrospective study of noncritically ill adults hospitalized between 2013 and 2021 and treated at least 48 hours for TZP-NS/CRO-S E coli or K pneumoniae infections. The primary composite endpoint included escalation to intensive care unit, infection- or treatment-related readmission, mortality, and infection recurrence. Outcomes were compared between groups who received carbapenem (CG) versus carbapenem-sparing agents (CSG) as targeted gram-negative therapy.

Results

Of 1062 patients screened, 200 were included (CG, n = 51; CSG, n = 149). Baseline characteristics, including Charlson Comorbidity Index (CCI; median [interquartile range], 6 [3–9] vs 6 [4–9]; P = .704), were similar between groups, except for more immunocompromised CG patients (29% vs 11%, P = .001). The most common infection sources were urinary (31% vs 57%, P = .002) and bloodstream (18% vs 17%, P = .887). Eighty-eight percent of the CG received meropenem, while 58% of the CSG received ceftriaxone as targeted therapy. There was no statistical difference in the primary endpoint between overall groups (27% vs 17%, P = .123), nor when stratified by infection source. More patients in the CSG switched to oral therapy (15 [29%] vs 100 [67%], P < .001). In multivariate analysis, CCI was an independent predictor of the primary outcome (odds ratio [OR], 1.199 [95% confidence interval, 1.074–1.340]; P = .001), while treatment with carbapenem-sparing therapy was not.

Conclusions

Our study did not find improved clinical outcomes with targeted carbapenem therapy for TZP-NS/CRO-S infections. Carbapenem-sparing agents may be considered to spare carbapenems in noncritically ill patients similar to those included in our cohort. Piperacillin-tazobactam–nonsusceptible/ceftriaxone-susceptible Enterobacterales have been increasingly identified in the New York metropolitan area. In noncritically ill patients with uncomplicated infections of this phenotype, carbapenem-sparing agents, including third-generation cephalosporins, may be considered.

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PROVIDER: S-EPMC10249260 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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