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. 2023 Feb 2;10(3):ofad052.
doi: 10.1093/ofid/ofad052. eCollection 2023 Mar.

Epidemiology and Clinical Outcomes of Non-HACEK Gram-Negative Infective Endocarditis

Sunish Shah  1   2 , Lloyd G Clarke  1   2 , Ryan K Shields  1   3
Affiliations

Epidemiology and Clinical Outcomes of Non-HACEK Gram-Negative Infective Endocarditis

Sunish Shah et al. Open Forum Infect Dis. .

Abstract

Background: The objectives of this study were to describe the changing epidemiology of gram-negative infective endocarditis (GNIE) and to identify factors associated with treatment failure and death.

Methods: Adult patients with GNIE were included if they met modified Duke criteria for definitive infective endocarditis (IE) between April 2010 and December 2021. Patients were identified using Boolean search terms. Clinical failure was a defined as a composite of all-cause 42-day mortality or microbiologic failure. All analyses were performed using Stata, version 15.1.

Results: One-hundred twenty-three patients were included. The most common pathogens were Serratia spp. (43%), Pseudomonas aeruginosa (21%), and Klebsiella spp. (14%). Fifty-two percent of cases were among persons who injection drugs (PWID; n = 64), for whom Serratia spp. (70%) was the most common cause of GNIE. Overall, patients infected with P. aeruginosa had higher microbiologic failure rates than other patients (23% vs 6%; P = .004). Patients who received combination therapy (n = 53) had comparable median lengths of stay (23 vs 19.5 days; P = .412), microbiologic failure rates (11.3% vs 7.1%; P = .528), clinical failure rates (18.9% vs 22.9%; P = .592), and 90-day mortality rates (13.2% vs 25.7%; P = .088) as those treated with monotherapy. After applying stepwise logistic regression, male gender, Pitt Bacteremia Score, and not receiving surgical intervention despite a surgical indication were associated with clinical failure.

Conclusions: This is the first study to identify Serratia spp. as the most common etiology of GNIE, which was particularly true among PWID. Microbiologic failures occurred most commonly among P. aeruginosa, and use of combination antimicrobial therapy did not improve clinical outcomes.

Keywords: IVDA; PWID; Serratia; endocarditis; gram-negative.

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Conflict of interest statement

Potential conflicts of interest. No funding sources were received for this study. R.K.S. has served as a consultant for Allergan, Cidara, Shionogi, Menarini, Melinta, Merck, Entasis, Utility, and Venatorx and has received investigator-initiated funding from Merck, Melinta, Shionogi, and Venatorx. All other authors report no potential conflicts.

Figures

Figure 1.
Figure 1.
Patient screening for study inclusion criteria. aSerratia spp. (n=3), Burkholderia spp., Acinetobacter spp., Klebsiella spp., S. maltophillia, E. coli. bAeromonas spp., P. multicoda, Brucella spp.
Figure 2.
Figure 2.
GNIE cases over time by pathogen. Abbreviation: GNIE, gram-negative infective endocarditis.
See this image and copyright information in PMC

References

    1. Von pycocyaneus-sptikamie mit komplizierender . Pyocyaneous endocarditis in kindesalter. Centrlabl f Bakt 1899; 25:113.
    1. Morpeth S, Murdoch D, Cabell CH, et al. . Non-HACEK gram-negative Bacillus endocarditis. Ann Intern Med 2007; 147:829–35. - PubMed
    1. Mills J, Drew D. Serratia marcescens endocarditis: a regional illness associated with intravenous drug abuse. Ann Intern Med 1976; 84:29–35. - PubMed
    1. Cooper R, Mills J. Serratia endocarditis. A follow-up report. Arch Intern Med 1980; 140:199–202. - PubMed
    1. Reyes MP, Ali A, Mendes RE, Biedenbach DJ. Resurgence of Pseudomonas endocarditis in Detroit, 2006–2008. Medicine (Baltimore) 2009; 88:294–301. - PubMed