A retrospective cohort study of Epstein-Barr virus infection status and systemic lupus erythematosus.

OBJECTIVES: Systemic lupus erythematosus (SLE) and the Epstein-Barr virus (EBV) are very closely related. This study estimated the impact of EBV infection status on clinical manifestations and disease remission in patients with SLE.

METHOD: A retrospective study was performed using electronic health records of patients with SLE. The SLE disease activity index (SLEDAI-2 K) was used to assess disease activity. VCAIgM or EAIgM positive or EBVDNA copies ≥ 50 IU/mL were defined as lytic infection group, EBNA-IgG or VCAIgG-positive and who were negative for both VCAIgM and EAIgM with EBVDNA copies < 50 IU/mL were defined as the latent infection group. The endpoint (disease remission) was defined as a decrease in SLEDAI-2 K score of ≥ 1 grade or ≥ 4 points from baseline. The association between EBV infection status and disease remission was assessed using propensity score weighting and multivariable Cox regression models.

RESULTS: There were 75 patients with SLE in the EBV lytic infection group and 142 patients in the latent infection group. The SLEDAI-2 K score was higher in the lytic infection group (10.00 (6.25, 16.00) vs. 8.00 (5.00, 10.00), Z = 3.96, P < 0.001). There was a significant difference in the effect of EBV lytic infection on disease remission compared to latent infection (HR 0.30, 95% CI 0.19-0.49, P < 0.001).

CONCLUSIONS: Patients with SLE with lytic EBV infection have higher disease activity and take longer to achieve remission. Our study furthers our understanding of the relationship between SLE and EBV infection and may inform better treatment practices in the future.