Anti-Smith antibody is associated with disease activity in patients with new-onset systemic lupus erythematosus
- 112 Downloads
Although anti-Smith (Sm) antibody is a highly specific antibody for systemic lupus erythematosus (SLE), the significance of anti-Sm antibody in patients with SLE is unclear. This study aimed to evaluate the association between anti-Sm antibodies and disease activity in patients with new-onset SLE. We included patients who were tested for anti-Sm antibodies at SLE diagnosis and within 12 months after diagnosis. SLE disease activity index (SLEDAI) was obtained at the time of the anti-Sm antibody test. The baseline disease activity was compared between patients with and without anti-Sm antibodies. The longitudinal association between disease activity and anti-Sm antibodies was also evaluated in total patients and in those with anti-Sm antibodies. Among 92 patients who were tested for anti-Sm antibodies at SLE diagnosis, 67 and another 67 patients were followed up for the presence of anti-Sm antibodies at 6 and 12 months, respectively. Although the baseline SLEDAI was comparable in patients with and without anti-Sm antibodies, the serum level of anti-Sm antibody was significantly correlated with SLEDAI (P = 0.003). At 12 months, anti-Sm antibody positivity was associated with higher SLEDAI and anti-dsDNA titer (P = 0.002, both). In addition, the changes in anti-Sm antibody titer over 12 months were correlated with the alterations in SLEDAI (P = 0.029).Anti-Sm antibody was associated with the baseline disease activity and the alteration of disease activity in patients with new-onset SLE. Monitoring of anti-Sm antibody titer may help assess the disease activity in SLE.
KeywordsSystemic lupus erythematosus Anti-Smith antibody Disease activity Systemic lupus erythematosus disease activity index
This study was supported for English editing service from Editage by Cactus.
SS Ahn and SM Jung conceived and designed the work; SS Ahn, J Yoo, and SM Jung acquired and analyzed the data; SS Ahn, S-W Lee, JJ Song, Y-B Park, and SM Jung interpreted the data; all authors contributed to drafting and revising the work, and approved the final version of the manuscript; all authors agreed to all aspects of the work.
Compliance with ethical standards
Conflict of interest
The authors declare no conflicts of interest.