Duthie Malcolm S, Orcullo Florenda M, Abbelana Junie, Maghanoy Armi, Balagon Marivic F
Infectious Disease Research Institute, 1616 Eastlake Ave E, Seattle, WA, 98102, USA.
Leonard Wood Memorial Center for Leprosy Research, Cebu, Philippines.
Appl Microbiol Biotechnol. 2016 Apr;100(7):3267-75. doi: 10.1007/s00253-016-7328-8. Epub 2016 Jan 28.
Despite control efforts, leprosy persists as a significant health concern in many regions. Diagnosis is achieved by a combination of clinical, histopathological, and bacteriological examinations, each of which presents a barrier to expeditious diagnosis, particularly by non-experts. Immunological investigations in research laboratories have clearly indicated that antibody detection tests could aid the diagnosis of leprosy. In this study, we detected circulating antibodies with two rapid diagnostic tests (RDT) involving immunochromatographic lateral flow platforms and one rapid ELISA system. Leprosy patients were identified with a high degree of sensitivity in each assay (over 80% in all; over 90% among cases with bacterial indices >1+), although critical differences were observed in specificity. While the specificity of CTK OnSite Leprosy Ab Rapid Test and InBios Leprosy Detect™ fast ELISA were high (96.4 and 93.7% in the general population, respectively), there was a marked reduction in OrangeLife NDO-LID® RDT (only 25.0%). As anticipated, seropositivity rates were marginally higher in contacts of leprosy patients than in endemic controls. Although we observed a slight drop in test band intensity when blood, rather than serum, was used to develop OnSite Leprosy Ab Rapid Tests, the sensitivity and specificity of these tests was unaffected. When we contrasted test performance with clinical and bacteriological information, we found that RDT and ELISA results positively correlated with the bacteriological index. These data indicate that these assays could be a ready replacement of invasive, insensitive, and time consuming skin slit smear procedures that additionally require expert microscopic examinations. We propose that, due to their speed and point of care applicability, the RDT could be used as an initial entry point to the diagnostic protocols, with confirmation of results attained in a highly quantitative manner following serum transfer to a reference laboratory.
尽管采取了防控措施，但麻风病在许多地区仍是一个重大的健康问题。麻风病的诊断需要结合临床、组织病理学和细菌学检查，而这些检查中的每一项都给快速诊断带来了障碍，尤其是对于非专业人员而言。研究实验室的免疫学调查清楚地表明，抗体检测试验有助于麻风病的诊断。在本研究中，我们使用两种基于免疫层析侧向流动平台的快速诊断试验（RDT）和一种快速酶联免疫吸附测定（ELISA）系统检测循环抗体。在每项检测中，麻风病患者均具有较高的敏感性（总体上超过80%；细菌指数>1+的病例中超过90%），尽管在特异性方面观察到了显著差异。虽然CTK现场麻风病抗体快速检测和InBios麻风病检测™快速ELISA的特异性较高（在普通人群中分别为96.4%和93.7%），但OrangeLife NDO-LID®RDT的特异性显著降低（仅为25.0%）。正如预期的那样，麻风病患者接触者的血清阳性率略高于地方性对照。尽管我们观察到，在使用血液而非血清进行现场麻风病抗体快速检测时，检测条带强度略有下降，但这些检测的敏感性和特异性并未受到影响。当我们将检测性能与临床和细菌学信息进行对比时，发现RDT和ELISA结果与细菌学指数呈正相关。这些数据表明，这些检测方法可以替代侵入性、不敏感且耗时的皮肤刮片涂片检查程序，而后者还需要专业的显微镜检查。我们建议，由于其速度和即时检测适用性，RDT可作为诊断方案的初始切入点，将血清转至参考实验室后，以高度定量的方式确认结果。
