Enterococci in Diabetic Foot Infections: Prevalence, Clinical Characteristics, and Outcomes

Ofer Perzon; Avivit Cahn; Yechiel N Gellman; Michal Leibovitch; Shahar Peled; Ofer Elishoov; Amir Haze; Karen Olshtain-Pops; Hila Elinav

doi:10.1093/ofid/ofad238

Enterococci in Diabetic Foot Infections: Prevalence, Clinical Characteristics, and Outcomes

Open Forum Infect Dis. 2023 May 3;10(5):ofad238. doi: 10.1093/ofid/ofad238. eCollection 2023 May.

Authors

Ofer Perzon^{1

2}, Avivit Cahn^{3

2}, Yechiel N Gellman^{4

2}, Michal Leibovitch^{5

6}, Shahar Peled^{5

6}, Ofer Elishoov^{4

2}, Amir Haze^{4

2}, Karen Olshtain-Pops^{7

2}, Hila Elinav^{7

2}

Affiliations

¹ Department of Internal Medicine, Hadassah Hebrew University Medical Center, Ein Kerem, Jerusalem, Israel.
² Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
³ Diabetes Unit, Department of Endocrinology and Metabolism, Hadassah Hebrew University Medical Center, Ein Kerem, Jerusalem, Israel.
⁴ Diabetic Foot Unit, Department of Orthopedics, Hadassah Hebrew University Medical Center, Ein Kerem, Jerusalem, Israel.
⁵ Department of Military Medicine and "Tzameret," Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
⁶ Medical Corps, Israel Defense Forces, Israel.
⁷ Department of Clinical Microbiology and Infectious diseases, Hadassah Hebrew University Medical Center, Ein Kerem, Jerusalem, Israel.

Abstract

Background: Diabetic foot infections (DFIs) are frequently polymicrobial, yet the relevance of each isolated pathogen, remains ill-defined. Specifically, the prevalence and pathogenicity of enterococcal DFIs and the impact of targeted antienterococcal treatment remain elusive.

Methods: We collected demographic, clinical, and outcome-related data on patients admitted with DFIs to the Hadassah Medical Center diabetic foot unit between 2014 and 2019. The primary outcome was a composite of in-hospital death or major amputation. Secondary outcomes included any amputation, major amputation, length of stay (LOS), and 1-year major amputation or mortality rate.

Results: Enterococci were isolated in 35% of 537 eligible DFI case patients, who were notable for a higher prevalence of peripheral vascular disease, increased levels of C-reactive protein, and higher Wagner scores. Infection in enterococci-positive individuals was mostly polymicrobial (96.8% vs 61.0% in non-enterococci-infected patients; P < .001). Enterococci-infected patients were more likely to undergo amputation (72.3% vs 50.1%; P < .001) and had longer hospital stays (median LOS, 22.5 vs 17 days; P < .001), but the primary end point of major amputation or in-hospital death did not differ between groups (25.5% vs 21.0%; P = .26). Appropriate antienterococcal antibiotics were used in 78.1% of enterococci-infected patients and, compared with results in untreated patients, were associated with a trend toward a lower rate of major amputations (20.4% vs 34.1%; P = .06) but longer hospitalization (median LOS, 24 vs 18 days; P = .07).

Conclusions: Enterococci are common in DFIs and associated with higher rates of amputation and longer hospitalization. A reduction in major amputation rates with appropriate enterococci treatment is suggested retrospectively, meriting validation by future prospective studies.

Keywords: amputation; diabetic foot infection; enterococci.