Division of Clinical Microbiology, Helsinki University Hospital Laboratory, Helsinki, Finland.
Lancet. 2010 Jan 16;375(9710):224-30. doi: 10.1016/S0140-6736(09)61569-5. Epub 2009 Dec 10.
New DNA-based microarray platforms enable rapid detection and species identification of many pathogens, including bacteria. We assessed the sensitivity, specificity, and turnaround time of a new molecular sepsis assay.
2107 positive blood-culture samples of 3318 blood samples from patients with clinically suspected sepsis were investigated for bacterial species by both conventional culture and Prove-it sepsis assay (Mobidiag, Helsinki, Finland) in two centres (UK and Finland). The assay is a novel PCR and microarray method that is based on amplification and detection of gyrB, parE, and mecA genes of 50 bacterial species. Operators of the test assay were not aware of culture results. We calculated sensitivity, specificity, and turnaround time according to Clinical and Laboratory Standards Institute recommendations.
1807 of 2107 (86%) positive blood-culture samples included a pathogen covered by the assay. The assay had a clinical sensitivity of 94.7% (95% CI 93.6-95.7) and a specificity of 98.8% (98.1-99.2), and 100% for both measures for meticillin-resistant Staphylococcus aureus bacteraemia. The assay was a mean 18 h faster than was the conventional culture-based method, which takes an additional 1-2 working days. 34 of 3284 (1.0%) samples were excluded because of technical and operator errors.
Definitive identification of bacterial species with this microarray platform was highly sensitive, specific, and faster than was the gold-standard culture-based method. This assay could enable fast and earlier evidence-based management for clinical sepsis.
新的基于 DNA 的微阵列平台能够快速检测和鉴定许多病原体，包括细菌。我们评估了一种新的分子败血症检测方法的灵敏度、特异性和周转时间。
对来自 3318 例疑似败血症患者的 3318 份血样中的 2107 份阳性血培养样本，在两个中心（英国和芬兰），使用传统培养和 Prove-it 败血症检测法（芬兰赫尔辛基的 Mobidiag），对细菌种类进行检测。该检测法是一种新型 PCR 和微阵列方法，基于 50 种细菌的 gyB、parE 和 mecA 基因的扩增和检测。该检测法的操作人员不知道培养结果。我们根据临床和实验室标准协会的建议计算灵敏度、特异性和周转时间。
2107 份阳性血培养样本中，1807 份（86%）包含该检测法涵盖的病原体。该检测法的临床灵敏度为 94.7%（95%CI 93.6-95.7），特异性为 98.8%（98.1-99.2），对耐甲氧西林金黄色葡萄球菌菌血症的两种测量方法均为 100%。该检测法比传统的基于培养的方法平均快 18 小时，后者需要额外的 1-2 个工作日。由于技术和操作人员的错误，3284 份样本中有 34 份（1.0%）被排除在外。
使用这种微阵列平台对细菌种类进行明确鉴定具有高度的敏感性、特异性和速度，优于金标准的基于培养的方法。该检测法可实现快速、更早的基于证据的败血症临床管理。
