Treatment effectiveness of antibiotic therapy in Veterans with multidrug-resistant Acinetobacter spp. bacteremia

Amanda Vivo; Margaret A Fitzpatrick; Katie J Suda; Geneva M Wilson; Makoto M Jones; Martin E Evans; Charlesnika T Evans

doi:10.1017/ash.2023.500

Treatment effectiveness of antibiotic therapy in Veterans with multidrug-resistant Acinetobacter spp. bacteremia

Antimicrob Steward Healthc Epidemiol. 2023 Dec 12;3(1):e230. doi: 10.1017/ash.2023.500. eCollection 2023.

Authors

Amanda Vivo¹, Margaret A Fitzpatrick^#^{2

3}, Katie J Suda^{4

5}, Geneva M Wilson^{1

6}, Makoto M Jones^{7

8}, Martin E Evans^{9

10}, Charlesnika T Evans^{1

6}

Affiliations

¹ Center of Innovation for Complex Chronic Healthcare (CINCCH), Edward Hines Jr. VA Medical Center, Hines, IL, USA.
² Center of Innovation for Veteran Centered and Value Drive Care, Rocky Mountain Regional VA Medical Center, Aurora, CO, USA.
³ University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
⁴ Center for Health Equity Research and Promotion, VA Pittsburgh Health Care System, Pittsburgh, PA, USA.
⁵ Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
⁶ Department of Preventive Medicine, Center for Health Services and Outcomes Research, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
⁷ Veterans Affairs Salt Lake City Health Care System, Salt Lake City, UT, USA.
⁸ Division of Epidemiology, Department of Internal Medicine, Spencer Fox Eccles School of Medicine, University of Utah, Salt Lake City, UT, USA.
⁹ VHA MRSA/MDRO Program Office, the National Infectious Diseases Service, Patient Care Services, VA Central Office and the Lexington VA Medical Center, Lexington, KY, USA.
¹⁰ Department of Internal Medicine, University of Kentucky School of Medicine, Lexington, KY, USA.

^# Contributed equally.

Abstract

Objective: To describe antimicrobial therapy used for multidrug-resistant (MDR) Acinetobacter spp. bacteremia in Veterans and impacts on mortality.

Methods: This was a retrospective cohort study of hospitalized Veterans Affairs patients from 2012 to 2018 with a positive MDR Acinetobacter spp. blood culture who received antimicrobial treatment 2 days prior to through 5 days after the culture date. Only the first culture per patient was used. The association between treatment and patient characteristics was assessed using bivariate analyses. Multivariable logistic regression models examined the relationship between antibiotic regimen and in-hospital, 30-day, and 1-year mortality. Generalized linear models were used to assess cost outcomes.

Results: MDR Acinetobacter spp. was identified in 184 patients. Most cultures identified were Acinetobacter baumannii (90%), 3% were Acinetobacter lwoffii, and 7% were other Acinetobacter species. Penicillins-β-lactamase inhibitor combinations (51.1%) and carbapenems (51.6%)-were the most prescribed antibiotics. In unadjusted analysis, extended spectrum cephalosporins and penicillins-β-lactamase inhibitor combinations-were associated with a decreased odds of 30-day mortality but were insignificant after adjustment (adjusted odds ratio (aOR) = 0.47, 95% CI, 0.21-1.05, aOR = 0.75, 95% CI, 0.37-1.53). There was no association between combination therapy vs monotherapy and 30-day mortality (aOR = 1.55, 95% CI, 0.72-3.32).

Conclusion: In hospitalized Veterans with MDR Acinetobacter spp., none of the treatments were shown to be associated with in-hospital, 30-day, and 1-year mortality. Combination therapy was not associated with decreased mortality for MDR Acinetobacter spp. bacteremia.