Fabre Valeria, Hsu Yea-Jen, Carroll Karen C, Milstone Aaron M, Salinas Alejandra B, Abbo Lilian M, Bower Chris, Berry Jennifer, Boyd Sarah, Degnan Kathleen O, Dhaubhadel Pragya, Diekema Daniel J, Dress Marci, Feeser Baevin, Fisher Mark, Flynn Cynthia, Ford Bradley A, Gettler Erin B, Glasser Laurel J, Howard-Anderson Jessica, Johnson J Kristie, Karaba Sara M, Kim Justin J, Kubischta Alyssa, Landrum Benjamin M, Martinez Marvin, Mathers Amy J, Mermel Leonard, Moehring Rebekah W, O'Horo John C, Pepe Dana E, Qasba S Sonia, Rittmann Barry, Robinson Evan D, Rodríguez-Nava Guillermo, Rosa Rossana, Ryder Jonathan H, Salinas Jorge L, Shah Aditya, Schrank Gregory M, Shelly Mark, Spivak Emily S, Stewart Kathleen O, Talbot Thomas R, Van Schooneveld Trevor C, Wasylyshyn Anastasia, Gadala Avinash, Virk Zunaira, Cosgrove Sara E
Department of Medicine, Division of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.
J Clin Microbiol. 2025 Aug 13;63(8):e0053025. doi: 10.1128/jcm.00530-25. Epub 2025 Jul 11.
Clinical and Laboratory Standards Institute (CLSI) recommends a blood culture contamination (BCC) threshold of <3%, with ≤1% considered optimal. However, there is not a standardized definition of BCC, and the effect of multiple definitions on BCC rates or what definitions laboratories use remain unknown. We surveyed 52 hospitals and analyzed 362,078 blood cultures (BCx) collected 1 September 2019 to 31 August 2021 from 62 intensive care units (ICUs) and 231 wards from 48 of these hospitals. We calculated and compared BCC rates using the College of American Pathologists (CAP) or CLSI criteria (both utilize a limited number of skin commensals to define BCC) and the comprehensive National Healthcare Safety Network (NHSN) commensal list. We characterized factors associated with BCC and related outcomes (central-line associated bloodstream infection [CLABSI] and vancomycin use). BCC, BCx positivity, and single BCx rates were monitored by 100%, 39%, and 21% of hospitals, respectively. Hospitals used CAP (65%), CLSI (17%), and NHSN (17%) criteria to define BCC. Mean BCC rate by CAP (CAP-BCC) was 1.38% for ICUs and 0.96% for wards. BCC rates remained similar by CLSI criteria but increased when using NHSN list. Sharing BCC data outside of the laboratory, measuring additional BCx quality indicators, and limiting central catheter-drawn BCx were associated with lower BCC rates. BCC was associated with higher CLABSI rates in ICUs. This study demonstrated variability in laboratory practices and opportunities to optimize BCx stewardship.IMPORTANCEBlood culture contamination (BCC) is associated with patient harm and unnecessary use of healthcare resources. BCC thresholds have been established; however, multiple BCC definitions exist. There is limited data on how BCC rates differ depending on the BCC definition used, what definitions laboratories most commonly use, or their approach to other blood cultures (BCx) quality indicators such as single rates or BCx positivity. A cross-sectional multicenter survey and analysis of BCx data from intensive care unit and wards revealed that most laboratories did not track single BCx or BCx positivity rates and that there was variability in how BCC was defined. Additionally, BCC rates were influenced by the definition used. BCC was associated with increased central-line associated bloodstream infection rates.
临床和实验室标准协会（CLSI）建议血液培养污染（BCC）阈值<3%，≤1%被认为是最佳的。然而，BCC并没有标准化的定义，多种定义对BCC率的影响或实验室使用何种定义仍不清楚。我们调查了52家医院，并分析了2019年9月1日至2021年8月31日期间从其中48家医院的62个重症监护病房（ICU）和231个病房采集的362,078份血培养（BCx）样本。我们使用美国病理学家协会（CAP）或CLSI标准（两者都利用有限数量的皮肤共生菌来定义BCC）以及全面的国家医疗安全网络（NHSN）共生菌列表计算并比较了BCC率。我们对与BCC及相关结果（中心静脉导管相关血流感染[CLABSI]和万古霉素使用）相关的因素进行了特征分析。分别有100%、39%和21%的医院监测了BCC、BCx阳性率和单个BCx率。医院使用CAP标准（65%）、CLSI标准（17%）和NHSN标准（17%）来定义BCC。ICU的CAP标准BCC平均率（CAP - BCC）为1.38%，病房为0.96%。按CLSI标准BCC率保持相似，但使用NHSN列表时BCC率会升高。在实验室之外共享BCC数据、测量额外的BCx质量指标以及限制通过中心静脉导管采集的BCx样本与较低的BCC率相关。在ICU中，BCC与较高的CLABSI率相关。本研究表明实验室操作存在差异以及优化BCx管理的机会。重要性血液培养污染（BCC）与患者伤害和医疗资源的不必要使用相关。已经制定了BCC阈值；然而，存在多种BCC定义。关于根据所使用的BCC定义BCC率如何不同、实验室最常用何种定义或其对其他血培养（BCx）质量指标（如单个率或BCx阳性率）的处理方式的数据有限。一项对来自重症监护病房和病房的BCx数据的横断面多中心调查和分析显示，大多数实验室没有追踪单个BCx或BCx阳性率，并且在BCC的定义方式上存在差异。此外,BCC率受所使用定义的影响。BCC与中心静脉导管相关血流感染率的增加相关。
