Enterococcal bacteraemia: predictive and prognostic risk factors for ampicillin resistance

Abstract

To identify the predictive and prognostic factors associated with ampicillin-resistant enterococcal bacteraemia, we retrospectively reviewed demographic, microbiological and clinical data of patients attending the Kyoto University Hospital, Japan, between 2009 and 2015. Logistic regression and Cox regression analyses were performed to determine the predictive and prognostic factors, respectively. In total, 235 episodes of enterococcal bacteraemia were identified. As ampicillin susceptibility was uniform for Enterococcus faecalis isolates and almost all ampicillin-resistant isolates were E. faecium, bacteraemia due to these species was investigated separately. E. faecalis and E. faecium accounted for 41.7% (98/235) and 48.1% (113/235) of the isolates, respectively and 91.2% of all E. faecium were ampicillin resistant. Nosocomial E. faecium bacteraemia acquisition (odds ratio (OR), 13.6; 95% confidence intervals, 3.16-58.3) was associated with ampicillin-resistant isolates. Bacteraemia from an unknown source (hazard ratio (HR), 2.91; 95% CI 1.36-6.21) and an increased Pitt bacteraemia score (PBS) (HR, 1.36; 95% CI 1.21-1.52) were associated with 30-day mortality in E. faecium infections. Likewise, bacteraemia from an unknown source (HR, 4.17; 95% CI 1.25-13.9) and increased PBS (HR, 1.27; 95% CI 1.09-1.48) were associated with 30-day mortality in patients with E. faecalis bacteraemia. The empirical therapeutic administration of glycopeptides is recommended for patients with bacteraemia from an unknown source in whom severe E. faecium bacteraemia is suspected.

Clinical Impact of Vancomycin Treatment in Ampicillin-Susceptible Enterococci Bloodstream Infections

“…Patients who had severe illness were treated as having enterococcal infection by physicians. Unsurprisingly, we found that the severity of illness and comorbidities were independent factors related to mortality, consistent with related studies [ 4 , 7 , 9 , 10 ].…”

“…The reported mortality rate of enterococcal bloodstream infections (BSI) was approximately 23 to 50% [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ]. Ampicillin or vancomycin resistance in enterococcal infections is a factor that had been associated with mortality [ 4 , 12 ].…”

“…However, few studies focused on vancomycin increasing mortality among patients with ASE BSI. The other reported risk factors associated with mortality from enterococcal bacteremia were the type of enterococcal species, the severity of infections, and comorbidities [ 3 , 6 , 9 , 10 ].…”

Ampicillin-susceptible Enterococcus faecium infections: clinical features, causal clades, and contribution of MALDI-TOF to early detection

“…In this context, it would be useful to be able to precisely identify the E. faecium strains responsible for severe infections. The clinical and epidemiological data associated with resistance (e.g., nosocomial acquisition) ( 14 ) must be taken into account when selecting the most appropriate treatment. However, tools accelerating the identification of enterococcal species could also provide a robust and complementary means of improving this choice.…”

Daptomycin versus Glycopeptides for the Treatment of Enterococcus faecium Bacteraemia: A Cohort Study

“…Concerning enterococcal bacteraemia, its incidence is increasing, especially that Antibiotics 2021, 10, 716 2 of 13 of E. faecium, which presents a worrisome annual increase of 19% in Europe [3]. Enterococcal BSI mortality ranges from 14-50%, being higher in the case of E. faecium compared to E. faecalis [2,4,5]. Specifically, ampicillin resistant and glycopeptide susceptible E. faecium (GSEF)-BSI mortality is 25-35% [6], whereas vancomycin resistant strains present a higher mortality [7].…”