Zhang Yuxian, Qu Xiaoxia, Wang Lishui, Song Lijun
Department of Rheumatology, Qilu Hospital, Shandong University, Jinan, China.
Qilu Hospital, Shandong Provincial Clinical Research Center for Immune Diseases and Gout, Jinan, China.
Front Med (Lausanne). 2024 Jan 19;11:1346609. doi: 10.3389/fmed.2024.1346609. eCollection 2024.
The presence of urinary autoantibodies in patients with systemic lupus erythematosus (SLE) has been confirmed by several studies; however, the significance of their presence in urine remains unclear. This study aims to further investigate the association between urine autoantibodies and disease activity as well as organ involvement in SLE.
This cross-sectional study included 89 SLE patients. Data collected included anti-nuclear antibody (ANA), anti-ENA antibodies, and anti-dsDNA antibody levels in both serum and urine, complement (C) 3, C4 levels in serum, SLE disease activity index-2000 (SLEDAI-2000), renal domains of SLEDAI (RSLEDAI) and non-renal SLEDAI (NRSLEDAI).
The rate of positive urine ANA (uANA) was 33.3% (29/87) among the enrolled patients. Compared to the uANA negative group, the positive group exhibited significantly higher SLEDAI-2000 scores (7.85 ± 5.88 vs. 18.69 ± 6.93, < 0.001), RSLEDAI scores [0 (0, 4.0) vs. 12.0 (8.0, 16.0), < 0.001], and NRSLEDAI [4 (2.0, 8.0) vs. 6.0 (4.0, 9.5), = 0.038]. Patients with positive urine anti-Sm antibody demonstrated significantly elevated SLEDAI-2000 scores compared to those who were negative (25.0 ± 8.80 vs. 10.09 ± 6.63, < 0.001). Similarly, they also had higher RSLEDAI [16.0 (12.0, 16.0) vs. 4.0 (0, 8.0), < 0.001] and NRSLEDAI [9.5 (6.0, 13.5) vs. 4.0 (3.0, 8.0), = 0.012], as well as a greater prevalence of renal involvement compared to their negative counterparts (100% vs. 58.2, = 0.022). There was a positive correlation between uANA titer and both SLEDAI-2000 ( = 0.663, < 0.001) and RSLEDAI ( = 0.662, < 0.001). The serum anti-dsDNA antibody level did not exhibit a significant correlation with RSLEDAI ( = 0.143, = 0.182). Conversely, the urine anti-dsDNA antibody level demonstrated a significant positive correlation with RSLEDAI ( = 0.529, < 0.001).
Urine ANA is associated with both global SLEDAI and RSLEDAI scores. Urine anti-Sm antibody is associated with an increased incidence of renal involvement in SLE. The urine anti-dsDNA antibody level, rather than the serum anti-dsDNA antibody level, exhibits a significant association with RSLEDAI in SLE.
多项研究已证实系统性红斑狼疮（SLE）患者尿液中存在自身抗体；然而，其在尿液中存在的意义仍不明确。本研究旨在进一步探究尿液自身抗体与SLE疾病活动度以及器官受累情况之间的关联。
本横断面研究纳入了89例SLE患者。收集的数据包括血清和尿液中的抗核抗体（ANA）、抗可提取核抗原（ENA）抗体、抗双链DNA（dsDNA）抗体水平、血清补体（C）3、C4水平、SLE疾病活动指数2000（SLEDAI - 2000）、SLEDAI的肾脏部分（RSLEDAI）和非肾脏部分（NRSLEDAI）。
在纳入的患者中，尿液ANA（uANA）阳性率为33.3%（29/87）。与uANA阴性组相比，阳性组的SLEDAI - 2000评分显著更高（7.85±5.88对18.69±6.93，P<0.001）、RSLEDAI评分[0（0，4.0）对12.0（8.0，16.0），P<0.001]以及NRSLEDAI评分[4（2.0，8.0）对6.0（4.0，9.5），P = 0.038]。尿液抗Sm抗体阳性的患者与阴性患者相比，SLEDAI - 2000评分显著升高（25.0±8.80对10.09±6.63，P<0.001）。同样，他们的RSLEDAI[16.0（12.0，16.0）对4.0（0，8.0），P<0.001]和NRSLEDAI[9.5（6.0，13.5）对4.0（3.0，8.0），P = 0.012]也更高，并且与阴性患者相比，肾脏受累的患病率更高（100%对58.2%，P = 0.022）。uANA滴度与SLEDAI - 2000（r = 0.663，P<0.001）和RSLEDAI（r = 0.662，P<0.001）均呈正相关。血清抗dsDNA抗体水平与RSLEDAI无显著相关性（r = 0.143，P = 0.182）。相反，尿液抗dsDNA抗体水平与RSLEDAI呈显著正相关（r = 0.529，P<0.001）。
尿液ANA与整体SLEDAI及RSLEDAI评分相关。尿液抗Sm抗体与SLE患者肾脏受累发生率增加相关。在SLE中，尿液抗dsDNA抗体水平而非血清抗dsDNA抗体水平与RSLEDAI显著相关。
