Predictors of flares in Systemic Lupus Erythematosus: Preventive therapeutic intervention based on serial anti-dsDNA antibodies assessment. Analysis of a monocentric cohort and literature review.

Patients with Systemic Lupus Erythematosus (SLE) may experience flare of disease activity. The aim of this study was to assess incidence, clinical features and predictors of flares, focusing on the relationship with serially assessed anti-double stranded DNA antibodies (anti-dsDNA) serum levels by Farr assay and pre-emptive therapeutic approaches of flares, through the analysis of a monocentric cohort of SLE patients and a literature review. Clinical and laboratory data of 120 out of 334 SLE patients, fulfilling inclusion criteria for enrolment and followed up between 1997 and 2012, were retrospectively collected. For the purposes of the study, a flare was defined as any new SLE manifestation or worsening of a pre-existing manifestation resulting in change of therapy. A review of the literature was performed searching for articles published between 1980 and 2015. Over a median (IQR) follow-up of 5.9 (3.0-8.9) years, 87 flares were recorded in 59 (49%) patients. The estimated incidence rate was 0.11 flare per patient-year, at the low-end of values reported in literature (0.19-1.76 patient-year). In our cohort, fluctuating anti-dsDNA serum levels were associated with flare development whereas precautionary change of therapy in presence of increased anti-dsDNA levels >50% was effective in preventing flares (p<0.05). Results from literature review highlighted that increasing anti-dsDNA and precautionary change of therapy were predictive and pre-emptive of flares, respectively, in some studies but not in others. Differences in laboratory methods and patient selection, in terms of ethnicity, disease duration, and background therapy are likely to be crucial in determining discordant results.