Ji Huimin, Chang Le, Yan Ying, Jiang Xinyi, Sun Huizhen, Guo Fei, Wang Lunan
National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China.
Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, China.
Front Microbiol. 2020 Jun 3;11:1151. doi: 10.3389/fmicb.2020.01151. eCollection 2020.
Serological tests have been widely used for detecting human T-cell lymphotropic virus type 1/2 (HTLV-1/2) antibodies in the endemic areas, but their performance in low-risk populations is rarely reported. The aim of this study was to evaluate the performance of four HTLV-1/2 screening assays and to discuss a strategy for diagnosis of HTLV-1/2 infection in a non-endemic area. At the present study, 1546 specimens repeatedly reactive (RR) by one screening ELISA were collected from blood centers/banks from January 2016 to April 2019. Avioq-ELISA, Murex-ELISA, Roche-ECLIA and Fujirebio-CLIA were independently performed on each plasma sample and compared to WB and LIA confirmatory tests. Positive or indeterminate specimens with blood available were quantified by qPCR. The results showed that 48 samples were finally confirmed as HTLV-1 positive, 13 were HTLV positive, 151 were indeterminate, and 387 were negative. All the WB-positive samples were also LIA-positive. Roche-ECLIA showed the highest sensitivity that was able to detect 91.8% positives and combined with the Murex-ELISA would significantly increase the positive detection rate (98.4%). In addition, LIA yield more indeterminate and HTLV-untyped results than WB (152 vs. 27), but was able to resolve infection status of some individuals with an indeterminate WB. Besides, 3 WB indeterminate and 1 LIA-untyped samples were confirmed as HTLV-1 positive by qPCR. Based on these findings, we put forward a proper test strategy for HTLV-1/2 diagnosis in low-prevalence areas. If possible, the Roche-ECLIA with the highest sensitivity is suggested as a second screening assay in primary labs. If not, all RR specimens are recommended to be firstly retested by Roche-ECLIA and Murex-ELISA in the reference lab. Secondly, samples reactive to any one of the two tests were quantified by qPCR, and then the NAT-negatives were furtherly submitted to LIA for confirmation. Thereby, the cost can be reduced and the diagnostic accuracy would be improved.
血清学检测已广泛用于在流行地区检测人类嗜T细胞病毒1型/2型（HTLV-1/2）抗体，但其在低风险人群中的表现鲜有报道。本研究的目的是评估四种HTLV-1/2筛查检测方法的性能，并讨论在非流行地区诊断HTLV-1/2感染的策略。在本研究中，2016年1月至2019年4月期间从血液中心/血库收集了1546份经一种筛查酶联免疫吸附测定（ELISA）反复呈反应性（RR）的标本。对每份血浆样本独立进行Avioq-ELISA、Murex-ELISA、罗氏电化学发光免疫分析（ECLIA）和富士瑞必欧化学发光免疫分析（CLIA），并与免疫印迹法（WB）和线性免疫分析（LIA）确证试验进行比较。对有可用血液的阳性或不确定标本进行定量聚合酶链反应（qPCR）检测。结果显示，最终确认48份样本为HTLV-1阳性，13份为HTLV阳性，151份为不确定，387份为阴性。所有WB阳性样本LIA也呈阳性。罗氏ECLIA显示出最高的灵敏度，能够检测出91.8%的阳性样本，与Murex-ELISA联合使用可显著提高阳性检出率（98.4%）。此外，LIA产生的不确定和HTLV未分型结果比WB更多（152对27），但能够解决一些WB结果不确定个体的感染状态。此外，3份WB不确定和1份LIA未分型样本经qPCR确认为HTLV-1阳性。基于这些发现，我们提出了在低流行地区诊断HTLV-1/2的合适检测策略。如果可能，建议在初级实验室将灵敏度最高的罗氏ECLIA作为二次筛查检测方法。如果不行，建议在参考实验室首先对所有RR标本用罗氏ECLIA和Murex-ELISA进行重新检测。其次，对两种检测中任何一种呈反应性的样本进行qPCR定量检测，然后将核酸检测阴性的样本进一步送LIA进行确证。从而可以降低成本并提高诊断准确性。
