Diagnostic accuracy and predictive value of autoantibody profiles in patients with systemic sclerosis: a single-center study

Objective To determine diagnostic accuracy and evaluate the predictive value of autoantibody profiles in patients with systemic sclerosis (SSc). Methods A total of 140 patients with SSc (125 female, mean age 54.2 +/- 14.2 years) were analyzed by a multiplex line immunoassay (Euroimmun) for autoantibodies against 12 SSc-related antigens. Associations between the presence of the autoantibodies and demographic clinical manifestations of patients with SSc were investigated. Results The sensitivity and specificity of this assay were as follows: 32.9% and 99.4% for anti-Scl-70, 29.3% and 88.9% for anti-CENP A, 28.6% and 87.8% for anti-CENP B, 7.1% and 97.8% for anti-RP11, 5.7% and 100% for anti-RP155, 2.9% and 99.4% for anti-NOR 90, 2.9% and 98.9% for anti-Th/To, 1.4% and 96.7% for anti-PM-Scl-100, 5.0% and 98.3% for anti-PM-Scl-75, and 2.9% and 97.2% for anti-Ku, respectively. Anti-Scl-70 was significantly associated with sine scleroderma (P = 0.003), digital ulcers (P = 0.047), and Raynaud's phenomenon as the first clinical manifestation of onset (P = 0.017). SSc-ILD was more common in patients with anti-Scl-70 (P = 0.029) and less frequent in patients with anti-CENP A (P < 0.001) and anti-CENP B (P < 0.001). There was a significant association between PAH with anti-CENP A (P = 0.008) and anti-CENP B (P = 0.025). Renal involvement was significantly related to anti-NOR90 (P = 0.026) and anti-Th/To (P = 0.026). Conclusions This study confirmed the important role of autoantibodies in accurately diagnosing SSc. The autoimmune profile of patients with SSc was related to specific disease manifestations.