PDF(Pubmed)
Abstract：
Antidouble-stranded DNA (dsDNA) antibodies are essential for diagnosis and follow-up of systemic lupus erythematous (SLE). To ensure the best diagnostic approach, most healthcare laboratories opt for a combination of highly sensitive methods, such as solid-phase immunoassays, and highly specific methods, such as the Crithidia luciliae indirect immunofluorescence test (CLIFT). Even so, discordant results are common, thus hindering the diagnostic process. Therefore, this study aimed to characterise a cohort of patients with discrepant results for a dsDNA fluorescence enzyme immunoassay (FEIA) and CLIFT during 2016-2018 and to follow patients up until December 2021.
We performed an observational, longitudinal and retrospective study on 417 samples from 257 patients who had been referred for suspected connective tissue diseases or followed up after diagnosis. All of them were positive for antinuclear antibodies (ANAs) using an indirect immunofluorescence assay (IFA) on Hep-2 cells, the entry criterion in our laboratory, and positive for FEIA dsDNA. Samples were then tested with CLIFT according to our routine protocol, which includes CLIFT testing after FEIA dsDNA results ≥10 UI/ml. After the assessment of data quality, the final analysis was based on 222 patients.
Eighty-three patients (37.4%) had positive results in both tests and met the diagnostic criteria for SLE. However, 139 patients (62.6%) had discrepant results (FEIA+, CLIFT-). Of these, 58 patients (41.7%) had a diagnosis of SLE, with 47 (33.8%) having been previously diagnosed and under treatment. The remaining 11 patients (7.9%) had a new diagnosis of SLE, which was made up within 4 years of the initial screening. A total of 81 of the 139 patients (57.5%) with discrepant results did not meet lupus criteria during the follow-up period.
The study showed that CLIFT could be negative in both treated and newly diagnosed SLE, thus underlining the importance of follow-up of dsDNA-positive results using solid-phase tests. Therefore, quantitative tests such as FEIA could add value to the diagnosis and management of patients with suspected SLE.
We performed an observational, longitudinal and retrospective study on 417 samples from 257 patients who had been referred for suspected connective tissue diseases or followed up after diagnosis. All of them were positive for antinuclear antibodies (ANAs) using an indirect immunofluorescence assay (IFA) on Hep-2 cells, the entry criterion in our laboratory, and positive for FEIA dsDNA. Samples were then tested with CLIFT according to our routine protocol, which includes CLIFT testing after FEIA dsDNA results ≥10 UI/ml. After the assessment of data quality, the final analysis was based on 222 patients.
Eighty-three patients (37.4%) had positive results in both tests and met the diagnostic criteria for SLE. However, 139 patients (62.6%) had discrepant results (FEIA+, CLIFT-). Of these, 58 patients (41.7%) had a diagnosis of SLE, with 47 (33.8%) having been previously diagnosed and under treatment. The remaining 11 patients (7.9%) had a new diagnosis of SLE, which was made up within 4 years of the initial screening. A total of 81 of the 139 patients (57.5%) with discrepant results did not meet lupus criteria during the follow-up period.
The study showed that CLIFT could be negative in both treated and newly diagnosed SLE, thus underlining the importance of follow-up of dsDNA-positive results using solid-phase tests. Therefore, quantitative tests such as FEIA could add value to the diagnosis and management of patients with suspected SLE.
摘要：
目的：抗双链DNA（dsDNA）抗体对于系统性红斑狼疮（SLE）的诊断和随访至关重要。为了确保最佳诊断方法，大多数医疗保健实验室选择高度敏感的方法的组合，如固相免疫测定，和非常具体的方法，如Crithidialucliae间接免疫荧光试验（CLIFT）。即便如此,不一致的结果很常见，从而阻碍了诊断过程。因此,本研究旨在对2016-2018年间dsDNA荧光酶免疫测定(FEIA)和CLIFT结果不一致的一组患者进行定性,并对患者进行随访至2021年12月.
方法：我们进行了观察，对257例疑似结缔组织疾病转诊或诊断后随访的患者的417个样本进行纵向和回顾性研究.在Hep-2细胞上使用间接免疫荧光测定（IFA），所有这些抗体均为抗核抗体（ANA）阳性，我们实验室的进入标准，FEIAdsDNA呈阳性。然后根据我们的常规方案用CLIFT测试样品，其中包括FEIAdsDNA结果≥10UI/ml后的CLIFT测试。经过对数据质量的评估,最终分析基于222例患者.
结果：83例患者（37.4%）在两项测试中均有阳性结果，符合SLE的诊断标准。然而,139例患者(62.6%)的结果不一致(FEIA+，CLIFT-).其中,58例（41.7%）诊断为SLE，其中47人(33.8%)先前已被诊断并正在接受治疗。其余11例患者（7.9％）新诊断为SLE，这是最初筛查后4年内完成的。在随访期间，139例结果不一致的患者中有81例（57.5％）不符合狼疮标准。
结论：研究表明，CLIFT在治疗和新诊断的SLE中均可能为阴性，因此强调了使用固相测试对dsDNA阳性结果进行随访的重要性。因此,FEIA等定量检测可以为疑似SLE患者的诊断和治疗增加价值.
方法：我们进行了观察，对257例疑似结缔组织疾病转诊或诊断后随访的患者的417个样本进行纵向和回顾性研究.在Hep-2细胞上使用间接免疫荧光测定（IFA），所有这些抗体均为抗核抗体（ANA）阳性，我们实验室的进入标准，FEIAdsDNA呈阳性。然后根据我们的常规方案用CLIFT测试样品，其中包括FEIAdsDNA结果≥10UI/ml后的CLIFT测试。经过对数据质量的评估,最终分析基于222例患者.
结果：83例患者（37.4%）在两项测试中均有阳性结果，符合SLE的诊断标准。然而,139例患者(62.6%)的结果不一致(FEIA+，CLIFT-).其中,58例（41.7%）诊断为SLE，其中47人(33.8%)先前已被诊断并正在接受治疗。其余11例患者（7.9％）新诊断为SLE，这是最初筛查后4年内完成的。在随访期间，139例结果不一致的患者中有81例（57.5％）不符合狼疮标准。
结论：研究表明，CLIFT在治疗和新诊断的SLE中均可能为阴性，因此强调了使用固相测试对dsDNA阳性结果进行随访的重要性。因此,FEIA等定量检测可以为疑似SLE患者的诊断和治疗增加价值.
