New York State Department of Health, Wadsworth Center Parasitology Laboratory, Albany, New York.
Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Parasitic Diseases Branch, Atlanta, Georgia.
Am J Trop Med Hyg. 2021 Nov 9;106(2):671-677. doi: 10.4269/ajtmh.21-0707.
For complex clinical cases where a parasitic infection is suspected, it can be difficult for clinicians to recommend an appropriate laboratory test. These tests are usually pathogen-specific and require a certain degree of suspicion for the precise etiology. A recently described assay, the universal parasite diagnostic (UPDx) can potentially provide a diagnosis of any parasite present in a specimen. Using primers that amplify DNA from all eukaryotes, UPDx differentiates several parasitic infections in blood by amplicon-based next-generation sequencing (NGS) of the 18S rDNA locus. As the state's public health reference laboratory, the Parasitology Laboratory at the Wadsworth Center (Albany, NY) receives specimens from patients who have potentially encountered a wide variety of parasites. As such, the ability to differentiate several blood parasites using a single assay is of interest. We assessed UPDx for its ability to confirm parasitic infections for 20 specimens that were previously identified by real-time PCR (RT-PCR). This included specimens positive for Babesia microti, Trypanosoma cruzi, Leishmania tropica, various Plasmodium species, and specimens comprising mixed Plasmodium sp. infections. Results obtained using UPDx were largely concordant with the RT-PCR assays. A T. cruzi positive specimen was negative by UPDx and for two mixed Plasmodium sp. infections only one species was detected. The results obtained for other specimens were concordant. We conclude that UPDx shows promise for the detection of blood parasites in diagnostic laboratories. As NGS becomes cheaper, assays like UPDx will become increasingly amenable to use in clinical settings.
对于怀疑寄生虫感染的复杂临床病例，临床医生可能难以推荐适当的实验室检测。这些检测通常是针对病原体的，并且需要对精确的病因有一定的怀疑。最近描述的一种检测方法，即通用寄生虫诊断（UPDx），可以潜在地提供标本中存在的任何寄生虫的诊断。UPDx 使用扩增所有真核生物 DNA 的引物，通过基于扩增子的下一代测序（NGS）对 18S rDNA 基因座进行区分，从而区分血液中的几种寄生虫感染。作为该州的公共卫生参考实验室，Wadsworth 中心（纽约州奥尔巴尼）的寄生虫学实验室从可能遇到各种寄生虫的患者那里接收标本。因此，使用单一检测方法区分几种血液寄生虫的能力很有意义。我们评估了 UPDx 对 20 个先前通过实时 PCR（RT-PCR）鉴定的标本的确认寄生虫感染的能力。这包括 B. microti、T. cruzi、L. tropica、各种疟原虫和混合疟原虫感染的标本。使用 UPDx 获得的结果与 RT-PCR 检测方法基本一致。一个 T. cruzi 阳性标本在 UPDx 中为阴性，对于两种混合疟原虫感染，仅检测到一种物种。其他标本的结果也一致。我们得出结论，UPDx 显示出在诊断实验室中检测血液寄生虫的潜力。随着 NGS 变得更便宜，像 UPDx 这样的检测方法将越来越适合在临床环境中使用。
