Comparative outcomes of daptomycin and linezolid in vancomycin-resistant enterococcal intra-abdominal infections with bacteraemia.

OBJECTIVE

We set out to see if daptomycin or linezolid (8-12 mg/kg) is effective for vancomycin-resistant enterococci (VRE) intra-abdominal infections (IAIs) because of its efficacy for VRE bloodstream infections (BSIs).

METHODS

We conducted a multicentre observational study. Between April 2010 and October 2024, we screened all patients with VRE-BSIs and included those with a documented VRE-IAI treated with daptomycin or linezolid. Limiting enrolment to patients with concurrent bloodstream infections reduced misclassification bias. The primary outcome was 28‑day in‑hospital mortality.

RESULTS

Of the 184 patients included, 149 received daptomycin and 35 received linezolid. Most patients (98.3%) underwent source control procedures. A total of 96 patients (52.2%) had hepatobiliary IAI, while 88 (47.8%) had non-biliary IAI. The 28-day mortality did not differ significantly between the daptomycin and linezolid groups (29.5% vs. 37.1%; P = .42). Multivariable logistic regression identified independent predictors of mortality, including higher Pitt bacteraemia score (adjusted OR [95% CI], 1.22 [1.06-1.41]; P = .006), lower platelet count (0.97 [0.94-0.99]; P = .02), and malignancy (2.41 [1.10-5.25]; P = .03). Daptomycin was not associated with increased mortality compared with linezolid (adjusted OR [95% CI], 0.63 [0.28-1.44]; P = .27). Daptomycin ≥11 mg/kg was linked to reduced mortality (adjusted OR [95% CI], 0.29 [0.09-0.91]; P = .03), whereas daptomycin 8-11 mg/kg showed no significant difference (0.79 [0.34-1.85]; P = .59). Findings were consistent in an augmented inverse probability weighting analysis.

CONCLUSIONS

Daptomycin is comparable with linezolid for treating VRE-IAI and BSI, with daptomycin ≥11 mg/kg associated with improved survival. Further investigations are warranted given the small sample size.