Strömdahl Martin, Hagman Karl, Hedman Karolina, Westman Anna, Hedenstierna Magnus, Ursing Johan
Department of Infectious Diseases, Danderyd Hospital, Stockholm, Sweden.
Department of Clinical Sciences, Karolinska Institutet, Danderyd Hospital, Stockholm.
Clin Infect Dis. 2025 Apr 30;80(4):727-734. doi: 10.1093/cid/ciae628.
Endocarditis occurs in approximately 10%-15% of patients with Staphylococcus aureus bacteremia (SAB). Short time to positivity (TTP) in blood culture flasks has been linked to endocarditis in smaller studies. This study evaluated the association between TTP and endocarditis in SAB in a large cohort.
Adult patients with ≥1 S. aureus positive blood culture treated at a tertiary-level, 500-bed hospital in Stockholm, Sweden between 2011-2021 were retrospectively identified. The primary outcome was the presence of infective endocarditis.
A total of 1703 episodes of SAB (23/1703 methicillin-resistant) in 1610 patients were included. Median age was 75 (interquartile range [IQR], 63-84) years and median Charlson comorbidity index score was 2 (IQR, 1-3). Echocardiography was performed in 1102/1703 (65%). Thirty-day mortality was 406/1703 (24%) and endocarditis was found in 154/1703 (9%). Median TTP was shorter in patients with endocarditis (9 [IQR, 7-12] hours) compared to patients without endocarditis (13 [interquartile range, 10-18] hours; P < .001). The risk of endocarditis decreased with 11% per hour (odds ratio [OR], 0.89 [95% confidence interval {CI}, .54-.92]; P < .001) in a univariate analysis using TTP as a continuous variable. In multivariate analysis, TTP <13 hours (the median) was independently associated with endocarditis (OR, 3.59 [95% CI, 2.35-5.3]; P < .001). The negative predictive value of TTP >13 hours for endocarditis was 96% (95% CI, 95%-97%).
Short TTP was associated with endocarditis. The negative predictive value of >95% suggests that TTP >13 hours can be used to risk-stratify patients with SAB.
金黄色葡萄球菌菌血症（SAB）患者中约10%-15%会发生感染性心内膜炎。在一些较小规模的研究中，血培养瓶中较短的阳性时间（TTP）与感染性心内膜炎有关。本研究在一个大型队列中评估了SAB患者TTP与感染性心内膜炎之间的关联。
回顾性纳入2011年至2021年期间在瑞典斯德哥尔摩一家拥有500张床位的三级医院接受治疗的血培养≥1次金黄色葡萄球菌阳性的成年患者。主要结局是感染性心内膜炎的存在。
共纳入1610例患者的1703次SAB发作（23/1703例耐甲氧西林）。中位年龄为75岁（四分位间距[IQR]，63-84岁），中位查尔森合并症指数评分为2分（IQR，1-3）。1102/1703例（65%）患者进行了超声心动图检查。30天死亡率为406/1703例（24%），154/1703例（9%）患者发现感染性心内膜炎。与无感染性心内膜炎的患者相比，感染性心内膜炎患者的中位TTP更短（9小时[IQR，7-12小时]）（13小时[四分位间距，10-18小时]；P<.001）。在以TTP作为连续变量的单因素分析中，感染性心内膜炎的风险每小时降低11%（比值比[OR]，0.89[95%置信区间{CI}，0.54-0.92]；P<.001）。在多因素分析中，TTP<13小时（中位数）与感染性心内膜炎独立相关（OR，3.59[95%CI，2.35-5.3]；P<.001）。TTP>13小时对感染性心内膜炎的阴性预测值为96%（95%CI，95%-97%）。
较短的TTP与感染性心内膜炎有关。>95%的阴性预测值表明TTP>13小时可用于对SAB患者进行风险分层。
