The spread of resistance to vancomycin and other last-resort drugs in Enterococcus spp. remains of concern. In Italy, surveillance data for enterococcal bloodstream isolates in humans are scant. The aim of our study was to assess the incidence trends of bacteremias due to Enterococcus species and their prevalence trends of antimicrobial resistance. We retrospectively included all consecutive not-duplicate Enterococcus species isolated from blood cultures, in patients from 11 Italian hospitals (2011–2017). Incidence was defined as the number of isolates per 10,000 patient-days, while resistance prevalence was defined as the number of resistant strains divided by the number of tested strains. We included 4,858 isolates (59%, 36%, and 5% due to Enterococcus faecalis, E. faecium, and other Enterococcus spp., respectively). Over the study period, the incidence of bacteremias due to E. faecalis (incidence rate ratio [IRR]: 1.02, 95% confidence interval [CI]: 1.00–1.04, p = 0.008) and E. faecium increased (IRR: 1.03, 95% CI: 1.01–1.05, p < 0.001) alongside with the whole enterococcal bacteremias trend (IRR: 1.02, 95% CIs: 1.01–1.04, p = 0.002). A progressive increase in vancomycin-resistant E. faecium (VREfm) bacteremias was observed. Resistance to tigecycline and linezolid was rarely reported. The incidence of enterococcal bloodstream isolates is increasing in Italy, together with the prevalence of VREfm. Resistance to linezolid, a cornerstone drug used in the treatment of VRE bloodstream infection, remains negligible.

中文翻译：

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肠球菌血流分离株的发病率和抗生素耐药性趋势：意大利一项为期 7 年的回顾性多中心流行病学研究

肠球菌属对万古霉素和其他最后的药物耐药性的传播。仍然令人担忧。在意大利，人体内肠球菌血流分离株的监测数据很少。我们研究的目的是评估肠球菌属菌血症的发生趋势及其抗菌素耐药性的流行趋势。我们回顾性地纳入了从 11 家意大利医院（2011-2017 年）的患者的血培养物中分离出的所有连续的非重复肠球菌属物种。发生率定义为每 10,000 个患者日的分离株数，而耐药流行率定义为耐药菌株的数量除以测试菌株的数量。我们纳入了 4,858 个分离株（59%、36% 和 5%，由于粪肠球菌、屎肠球菌和其他肠球菌属）。在研究期间，由于菌血症的发病率粪肠球菌（发病率比[IRR]：1.02，95％置信区间[CI]：1.00-1.04，p  = 0.008）和屎肠球菌增加（IRR：1.03， 95% CI：1.01–1.05，p  < 0.001）以及整个肠球菌菌血症趋势（IRR：1.02，95% CI：1.01–1.04，p  = 0.002）。耐万古霉素的粪肠球菌逐渐增多(VRefm) 菌血症被观察到。很少报道对替加环素和利奈唑胺耐药。在意大利，肠球菌血流分离株的发病率正在增加，同时 VREfm 的流行也在增加。对用于治疗 VRE 血流感染的基石药物利奈唑胺的耐药性仍然可以忽略不计。