Kocaeli Üniversitesi Tıp Fakültesi Tıbbi Mikrobiyoloji Anabilim Dalı, Kocaeli, Turkey.
Kocaeli Üniversitesi Tıp Fakültesi Tıbbi Mikrobiyoloji Anabilim Dalı, Kocaeli, Turkey.
J Immunol Methods. 2020 May;480:112754. doi: 10.1016/j.jim.2020.112754. Epub 2020 Feb 11.
It is has been proposed that the presence of anti-DFS70 antibodies could be used to eliminate a SARD diagnosis. However, anti-DFS70 antibodies were also observed at relatively high frequency in patients with SARD. The clinical significance of these antibodies is therefore not yet clear. In this study, we assessed the clinical significance of the presence of anti-DFS70 antibodies.
A total of 3432 sera samples were obtained from patients who underwent routinely requested ANA screening in the clinical laboratory of a University Hospital, between June 2017 and June 2019. Antinuclear antibody testing was performed by indirect immunofluorescence (IIF) on Hep-2 cell substrates (Euroimmun, Germany), and anti-ENA were measured by LIA (Euroimmun, Germany).
Among 3432 serum samples tested for ANA, 57.3% were ANA positive by IIF. Participants had mean age of 46.4 and 74.8% of the participants were female. Only 11.4% of the study population had SARD. The frequency of DFS pattern by IIF was 8.1%. Analysis of the DFS pattern positive samples by LIA revealed the presence of anti-DFS70 autoantibodies in 67.5% of all DFS, AC-2 pattern ANAs. When using the results of the ANA IIF HEp-2 DFS pattern/Anti-DFS70 LIA, likelihood ratio (LR) for SARD was 0.33. When comparing the ANA IIF HEp-2 DFS pattern with anti-DFS70 LIA, the ANA IIF HEp-2 DFS pattern's LR was lower (0.63 vs 0.85).
Although the DFS pattern cannot exclude the presence of SARD, the likelihood is lower than with other patterns. Therefore, anti-DFS70 antibodies represent an important biomarker that can aid in the interpretation of positive ANA patients and, therefore, should be included in test algorithms for ANA testing. The optimal test algorithm might be laboratory specific being dependent on referral patterns for ANA testing.
据提出，抗 DFS70 抗体的存在可用于排除 SARD 诊断。然而，抗 DFS70 抗体在 SARD 患者中也观察到相对较高的频率。因此，这些抗体的临床意义尚不清楚。在这项研究中，我们评估了抗 DFS70 抗体存在的临床意义。
本研究共纳入 2017 年 6 月至 2019 年 6 月期间在某大学附属医院临床实验室进行常规抗核抗体（ANA）筛查的 3432 例血清样本。采用间接免疫荧光法（IIF）在 Hep-2 细胞底物上检测抗核抗体（ANA）（德国 Euroimmun），采用 LIA 法（德国 Euroimmun）检测抗可提取性核抗原（ENA）抗体。
在 3432 例接受 ANA 检测的血清样本中，IIF 法检测到 57.3%的患者 ANA 阳性。参与者的平均年龄为 46.4 岁，74.8%为女性。仅有 11.4%的研究人群患有 SARD。IIF 法检测到 DFS 模式的频率为 8.1%。通过 LIA 对 DFS 模式阳性样本进行分析显示，所有 DFS（AC-2 模式 ANA）中 67.5%存在抗 DFS70 自身抗体。当使用 ANA IIF HEp-2 DFS 模式/抗 DFS70 LIA 结果时，SARD 的似然比（LR）为 0.33。与 ANA IIF HEp-2 DFS 模式相比，抗 DFS70 LIA 的 LR 更低（0.63 对 0.85）。
尽管 DFS 模式不能排除 SARD 的存在，但可能性低于其他模式。因此，抗 DFS70 抗体是一种重要的生物标志物，可辅助解释阳性 ANA 患者的结果，因此应纳入 ANA 检测的试验算法中。最佳的试验算法可能因实验室而异，取决于 ANA 检测的转诊模式。
