Driscoll Amanda J, Karron Ruth A, Bhat Niranjan, Thumar Bhagvanji, Kodani Maja, Fields Barry S, Whitney Cynthia G, Levine Orin S, O'Brien Katherine L, Murdoch David R
International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
J Microbiol Methods. 2014 Dec;107:222-6. doi: 10.1016/j.mimet.2014.10.009.
Several commercial assays are now available to detect the nucleic acid of multiple respiratory pathogens from a single specimen. Head-to-head comparisons of such assays using a single set of standard specimens provide additional information about key assay parameters such as sensitivity, specificity and lower limits of detection, and help to inform the decision regarding which method to use. We evaluated two real-time PCR platforms: the Fast-track Diagnostics® (FTD) multiplex respiratory panel and a TaqMan array card (TAC) for simultaneous uniplex detection of multiple respiratory pathogens. Two sets of samples were used to evaluate the assays. One set was created by spiking pooled nasal wash or phosphate buffered saline with specified volumes of known concentrations of virus and/or bacteria. Clinical nasal wash specimens from children with lower respiratory tract illness comprised the other set. Thirteen pathogen targets were compared between the two platforms. Testing with a validation panel of spiked samples revealed a sensitivity of 96.1% and 92.9% for the FTD and TAC assays, respectively. Specificity could not be reliably calculated due to a suspected contamination of the sample substrate. Inter-assay agreement was high (> 95%) for most targets. Previously untested clinical specimens tested by both assays revealed a high percent agreement (> 95%) for all except rhinovirus, enterovirus and Streptococcus pneumoniae. Limitations of this evaluation included extraction of the validation samples by two different methods and the evaluation of the assays in different laboratories. However, neither of these factors significantly impacted inter-assay agreement for these sets of samples, and it was demonstrated that both assays could reliably detect clinically relevant concentrations of bacterial and viral pathogens.
现在有几种商业检测方法可用于从单个样本中检测多种呼吸道病原体的核酸。使用同一组标准样本对这些检测方法进行直接比较，可提供有关关键检测参数（如灵敏度、特异性和检测下限）的更多信息，并有助于就使用哪种方法做出决策。我们评估了两种实时PCR平台：Fast-track Diagnostics®（FTD）多重呼吸道检测板和TaqMan阵列卡（TAC），用于同时对多种呼吸道病原体进行单重检测。使用两组样本对这些检测方法进行评估。一组样本是通过向混合的鼻腔灌洗样本或磷酸盐缓冲盐水中加入特定体积的已知浓度的病毒和/或细菌制成的。另一组样本包括患有下呼吸道疾病儿童的临床鼻腔灌洗标本。在两个平台之间比较了13种病原体靶点。对加标样本验证组进行检测发现，FTD和TAC检测的灵敏度分别为96.1%和92.9%。由于怀疑样本底物受到污染，无法可靠地计算特异性。对于大多数靶点，检测间的一致性较高（>95%）。两种检测方法对之前未检测过的临床标本进行检测，结果显示除鼻病毒、肠道病毒和肺炎链球菌外，所有标本的一致性百分比都很高（>95%）。本次评估的局限性包括通过两种不同方法提取验证样本，以及在不同实验室对检测方法进行评估。然而，这些因素均未对这几组样本的检测间一致性产生显著影响，并且证明两种检测方法均能可靠地检测出临床相关浓度的细菌和病毒病原体。
