Diagnostic significance of combined anti-extractable nuclear antigens antibody, anti-cardiolipin antibody and anti-β2-glycoprotein 1 in systemic lupus erythematosus patients.

OBJECTIVE: This study aimed to investigate the diagnostic value of a combination of anti-extractable nuclear antigens (anti-ENA) antibodies, anti-cardiolipin antibodies (ACA), and anti-β2-glycoprotein 1 (anti-β2 GPI) antibodies in patients with systemic lupus erythematosus (SLE).

METHODS: A total of 646 SLE patients diagnosed in our hospital between January 2020 and April 2023 were randomly selected as study subjects, while 2075 non-SLE subjects during the same period were selected as the control group. The levels of anti-extractable nuclear antigen (ENA) antibody, ACA, and anti-β2 GPI antibodies were measured, and their diagnostic value for SLE was analyzed using binary logistic regression and receiver operating characteristic (ROC) analysis.

RESULTS: The rates of positive anti-RNP, anti-Sm, anti-Sjögren's syndrome (SS-A), and anti-SS-B antibodies in the SLE patient group were significantly higher than those in the control group, with all differences being statistically significant (P < 0.01). The rates of positive ACA, as well as the levels of ACA IgA, ACA IgG, and ACA IgM, were significantly higher in the SLE patients group compared to the control group, with statistically differences (P < 0.05). Similarly, the rates of positive anti-β2 GPI antibodies, anti-β2 GPI antibody IgA, IgG, and IgM, were significantly higher in the SLE patient group compared to the control group, with all differences being statistically significant (P < 0.01). Gender, age, positive anti-JO1 antibodies, positive anti-RNP antibodies, positive anti-SS-A antibodies, positive ACA, high level ACA IgG and ACA IgM, positive anti-β2 GPI antibodies, and high level of anti-β2 GPI antibody IgA were identified as independent risk factors for the development of SLE (P < 0.05). The combined use of age, sex, anti-ENA antibodies, ACA, and anti-β2 GPI antibodies yielded a sensitivity of 82.12% (80.41%-83.71%) and a specificity of 80.03% (76.77%-82.93%) for the diagnosis of SLE.

CONCLUSION: The combination of age, sex, anti-ENA antibodies, ACA, and anti-β2 GPI antibodies shows high diagnostic value for SLE and holds potential for clinical application as an auxiliary diagnostic tool for SLE.