Monitoring of Serum TWEAK Level Guides Glucocorticoid Dosages in the Treatment of Systemic Lupus Erythematosus

Objective: Accurate assessment of systemic lupus erythematosus (SLE) disease activity is critical. This study explored the relationship between the serum level of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) and the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score as well as the role of TWEAK in guiding the glucocorticoid dosage in SLE treatment. Methods: This study involved 131 patients with SLE, 34 with subacute cutaneous lupus erythematosus (SCLE), 22 with discoid lupus erythematosus (DLE), and 32 healthy volunteers. The serum and urinary TWEAK levels were determined. Monomeric C-reactive protein (mCRP), anti-dsDNA IgG, antinuclear antibody (ANA), complements in serum and urinary albumin level were measured. The SLEDAI 2000 (SLEDAI-2K) was used to evaluate disease activity. The correlation of the SLEDAI-2K score with all biomarkers was determined. Methylprednisolone was orally administered to patients with SLE depending on the serum level of TWEAK. Results: TWEAK levels were higher in patients with SLE or SCLE than in patients with DLE or healthy controls. The serum TWEAK level was positively correlated with the SLEDAI-2K score in patients with SLE ( P < 0.001), and was more strongly correlated with the SLEDAI-2K score than other parameters ( P < 0.001). Moreover, TWEAK-based glucocorticoid therapy was associated with lower SLEDAI-2K scores, better tapering of glucocorticoid doses, and fewer lupus flares in patients with SLE. Conclusions: Serum TWEAK is a useful biomarker reflecting SLE disease activity. Monitoring of the serum TWEAK level can improve the outcomes of glucocorticoid therapy in patients with SLE.