Improved sensitivity of the urine CAA lateral-flow assay for diagnosing active Schistosoma infections by using larger sample volumes.
Improved sensitivity of the urine CAA lateral-flow assay for diagnosing active Schistosoma infections by using larger sample volumes.
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DOI：
10.1186/s13071-015-0857-7
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发表时间：
2015-04-22
影响因子：
3.2
通讯作者：
van Dam GJ
中科院分区：
文献类型：
--
作者：
Corstjens PL;Nyakundi RK;de Dood CJ;Kariuki TM;Ochola EA;Karanja DM;Mwinzi PN;van Dam GJ
准确测定低流行地区的血吸虫感染率以检查阻断传播和消除进展情况需要高度灵敏的诊断工具。现有的基于侧流 (LF) 的测试通过检测蠕虫循环阳极抗原 (CAA) 来证明持续感染，通过实施允许增加样本输入的方案，提高了灵敏度。尿液是首选样本，因为采集是非侵入性的，并且样本量通常不受限制。离心过滤装置提供了一种浓缩三氯乙酸（TCA）提取的尿样上清液的方法。对于现场试验，实际样本量为 2 mL 尿液，可以检测到低至 0.3 pg/mL 的 CAA。该方法对来自曼氏链球菌流行地区（肯尼亚基苏木）的一组尿液样本（n = 113）进行了评估，并与粪便显微镜检查（Kato Katz，KK）进行了比较。在此分析中，真阳性被定义为 KK 或 UCAA 测试呈阳性的样本。当尿液样本输入量从标准 10 μL（UCAA10 测定）改为 2000 μL（UCAA2000 测定）时，浓缩方法的实施将临床灵敏度 (Sn) 从 44% 提高到 98%。对于重复的 KK（单次粪便，两张载玻片），KK 的 Sn 变化范围为 23% 至 35%；对于六倍 KK（连续三天的粪便，两张载玻片），KK 的 Sn 变化范围为 52%。 UCAA2000 检测显示 47 个阳性样本的 CAA 浓度高于 0.3 pg/mL。六倍KK检测出25个卵子呈阳性；在 6 倍 KK 中检测到的 1 个含有 2 个鸡蛋的样品未通过 UCAA2000 检测进行鉴定。更大的样本输入将 UCAA 检测的 Sn 增加到表明“真实”感染的水平。只需要 2 mL 尿液样本，但分析更大的样本量仍然可以提高测试准确性。 UCAA2000 测试是准确识别低流行地区所有感染者的合适候选者。分析材料不需要冷藏，收集的尿液样本可以储存并运输到中心测试实验室，无需冷冻。
Accurate determination of Schistosoma infection rates in low endemic regions to examine progress towards interruption of transmission and elimination requires highly sensitive diagnostic tools. An existing lateral flow (LF) based test demonstrating ongoing infections through detection of worm circulating anodic antigen (CAA), was improved for sensitivity through implementation of a protocol allowing increased sample input. Urine is the preferred sample as collection is non-invasive and sample volume is generally not a restriction. Centrifugal filtration devices provided a method to concentrate supernatant of urine samples extracted with trichloroacetic acid (TCA). For field trials a practical sample volume of 2 mL urine allowed detection of CAA down to 0.3 pg/mL. The method was evaluated on a set of urine samples (n = 113) from an S. mansoni endemic region (Kisumu, Kenya) and compared to stool microscopy (Kato Katz, KK). In this analysis true positivity was defined as a sample with either a positive KK or UCAA test. Implementation of the concentration method increased clinical sensitivity (Sn) from 44 to 98% when moving from the standard 10 μL (UCAA10 assay) to 2000 μL (UCAA2000 assay) urine sample input. Sn for KK varied between 23 and 35% for a duplicate KK (single stool, two slides) to 52% for a six-fold KK (three consecutive day stools, two slides). The UCAA2000 assay indicated 47 positive samples with CAA concentration above 0.3 pg/mL. The six-fold KK detected 25 egg positives; 1 sample with 2 eggs detected in the 6-fold KK was not identified with the UCAA2000 assay. Larger sample input increased Sn of the UCAA assay to a level indicating ‘true’ infection. Only a single 2 mL urine sample is needed, but analysing larger sample volumes could still increase test accuracy. The UCAA2000 test is an appropriate candidate for accurate identification of all infected individuals in low-endemic regions. Assay materials do not require refrigeration and collected urine samples may be stored and transported to central test laboratories without the need to be frozen.
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影响因子：
3.8
作者：
Bobosha K;Tjon Kon Fat EM;van den Eeden SJ;Bekele Y;van der Ploeg-van Schip JJ;de Dood CJ;Dijkman K;Franken KL;Wilson L;Aseffa A;Spencer JS;Ottenhoff TH;Corstjens PL;Geluk A
通讯作者：
Geluk A
影响因子：
4.5
作者：
Knopp S;Mohammed KA;Ali SM;Khamis IS;Ame SM;Albonico M;Gouvras A;Fenwick A;Savioli L;Colley DG;Utzinger J;Person B;Rollinson D
通讯作者：
Rollinson D
DOI：
10.1016/0035-9203(89)90507-5
发表时间：
1989-05-01
影响因子：
2.2
作者：
DEJONGE, N;DECALUWE, P;DEELDER, AM
通讯作者：
DEELDER, AM
影响因子：
3.8
作者：
Grimes JE;Croll D;Harrison WE;Utzinger J;Freeman MC;Templeton MR
通讯作者：
Templeton MR
影响因子：
9.4
作者：
Corstjens, Paul L. A. M.;van Lieshout, Lisette;van Dam, Govert J.
通讯作者：
van Dam, Govert J.