There is a critical need for an improved rapid diagnostic for enteric fever. We have previously demonstrated that serum IgA responses targeting Salmonella enterica serovar Typhi hemolysin E (HlyE) and lipopolysaccharide (LPS) are able to discriminate patients with acute typhoid from healthy controls in areas where enteric fever is endemic (healthy endemic controls) and from patients with other bacterial infections. We now have data demonstrating that IgA antibody responses against these antigens also work well for identifying patients with acute S. Paratyphi A infection. To develop a test for acute enteric fever detection, we have adapted a point-of-care immunochromatographic dual-path platform technology (DPP), which improves on the traditional lateral flow technology by using separate sample and conjugate paths and a compact, portable reader, resulting in diagnostics with higher sensitivity and multiplexing abilities. In this analysis, we have compared our standard enzyme-linked immunosorbent assay (ELISA) method to the DPP method in detecting acute phase plasma/serum anti-HlyE and anti-LPS IgA antibodies in a cohort of patients with culture-confirmed S. Typhi (n = 30) and Paratyphi A infection (n = 20), healthy endemic controls (n = 25), and febrile endemic controls (n = 25). We found that the DPP measurements highly correlated with ELISA results, and both antigens had an area under the curve (AUC) of 0.98 (sensitivity of 92%, specificity of 94%) with all controls and an AUC of 0.98 (sensitivity of 90%, specificity of 96%) with febrile endemic controls. Our results suggest that the point-of-care DPP Typhoid System has high diagnostic accuracy for the rapid detection of enteric fever and warrants further evaluation.

中文翻译：

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快速护理点多重免疫层析检测诊断肠热病的评估。


迫切需要改进肠热病的快速诊断方法。我们之前已经证明，针对肠沙门氏菌伤寒血清型伤寒溶血素 E (HlyE) 和脂多糖 (LPS) 的血清 IgA 反应能够将急性伤寒患者与肠热病流行地区的健康对照者（健康地方性对照）以及患有肠热病的患者区分开来。其他细菌感染。我们现在有数据表明，针对这些抗原的 IgA 抗体反应也可以很好地识别急性甲型副伤寒沙门氏菌感染患者。为了开发急性肠热病检测测试，我们采用了即时免疫色谱双路径平台技术 (DPP)，该技术通过使用单独的样品和结合路径以及紧凑的便携式读取器，改进了传统的侧流技术，从而实现具有更高灵敏度和多重能力的诊断。在本分析中，我们将标准酶联免疫吸附测定 (ELISA) 方法与 DPP 方法在检测一组经培养确诊的伤寒沙门氏菌患者的急性期血浆/血清抗 HlyE 和抗 LPS IgA 抗体方面进行了比较( n = 30) 和甲型副伤寒感染 ( n = 20)、健康地方病对照 ( n = 25) 和发热地方病对照 ( n = 25)。我们发现 DPP 测量值与 ELISA 结果高度相关，两种抗原的曲线下面积 (AUC) 均为 0.98（敏感性为 92%，特异性为 94%），所有对照的曲线下面积 (AUC) 均为 0.98（敏感性为 90%） ，特异性为 96%）与发热性地方病对照。 我们的结果表明，护理点 DPP 伤寒系统对于快速检测肠热病具有较高的诊断准确性，值得进一步评估。