University of Louisville, Department of Medicine, Division of Infectious Diseases, Infectious Diseases Laboratory, 511 S. Floyd St, Medical Dental Research Building Room 104, Louisville, KY 40292 USA.
Ticks Tick Borne Dis. 2020 May;11(3):101387. doi: 10.1016/j.ttbdis.2020.101387. Epub 2020 Feb 1.
Cases of tick-borne diseases are increasing in the United States, and new tick-borne pathogen species causing human illness are being discovered. The specific etiology is generally difficult to diagnose based on clinical signs and symptoms alone, because of their generalized nature and often lack of a known tick bite. For some infections, such as Lyme disease and spotted fever group rickettsioses, serology remains the most appropriate laboratory diagnostic tool, but for others such as anaplasmosis, ehrlichiosis, and babesiosis, direct detection in the blood is preferred for rapid diagnosis. In Kentucky, USA, the area served by our laboratory, the most commonly reported tick-borne illnesses include spotted fever group rickettsiosis, ehrlichiosis and Lyme disease, but of these three diseases, only ehrlichiosis is well-suited for direct detection using PCR methods during the acute stage of illness. We report here the validation of a duplex real-time PCR assay using whole blood specimens on the Luminex ARIES® instrument, combining DNA extraction, amplification and detection into a one-step process. This method allows for rapid and sensitive detection of acute infections with Ehrlichia spp. and Anaplasma phagocytophilum using whole blood specimens. We included A. phagocytophilum to monitor emergence of this pathogen in Kentucky, since surrounding states have reported many more cases than Kentucky.
美国的蜱传疾病病例正在增加，并且新的蜱传病原体正在被发现，可导致人类疾病。由于其普遍性，且通常缺乏已知的蜱叮咬，仅根据临床体征和症状通常难以诊断具体病因。对于某些感染，如莱姆病和斑点热群立克次体病，血清学仍然是最适当的实验室诊断工具，但对于其他感染，如无形体病、埃立克体病和巴贝斯虫病，直接在血液中检测更适合快速诊断。在美国肯塔基州，我们实验室服务的地区，最常报告的蜱传疾病包括斑点热群立克次体病、埃立克体病和莱姆病，但在这三种疾病中，只有埃立克体病在疾病的急性阶段非常适合使用 PCR 方法进行直接检测。我们在此报告了一种使用 Luminex ARIES®仪器上的全血标本的双重实时 PCR 检测方法的验证，该方法将 DNA 提取、扩增和检测结合到一个步骤中。该方法允许使用全血标本快速和敏感地检测急性感染的埃立克体病和嗜吞噬细胞无形体。我们包括嗜吞噬细胞无形体来监测这种病原体在肯塔基州的出现，因为周围的州报告的病例比肯塔基州多得多。
