Impact of first wave of SARS-CoV-2 infection in patients with Systemic Lupus Erythematosus: Weighting the risk of infection and flare

INTRODUCTION: The aim of this study was to investigate the incidence and clinical presentation of SARS-CoV-2 infections in a Systemic Lupus Erythematosus (SLE) cohort; to assess correlations with disease characteristics and rheumatic therapy; and to evaluate the occurrence of treatment discontinuation and its impact on disease activity. MATERIALS AND METHODS: SLE patients monitored by a single Italian centre were interviewed between February and July 2020. Patients were considered to be positive for SARS-CoV-2 infections in case of 1) positive nasopharyngeal swab; 2) positive serology associated with COVID19 suggesting symptoms. The following data were also recorded: clinical symptoms, adoption of social distancing measures, disease activity and treatment discontinuation. RESULTS: 332 patients were enrolled in the study. Six patients (1.8%) tested positive for SARS-CoV-2 infection, with the incidence being significantly higher in the subgroup of patients treated with biological Disease-Modifying Anti-Rheumatic Drugs (p = 0.005), while no difference was observed for other therapies, age at enrollment, disease duration, type of cumulative organ involvement or adoption of social isolation. The course of the disease was mild. Thirty-six patients (11.1%) discontinued at least part of their therapy during this time period, and 27 (8.1%) cases of disease flare were recorded. Correlation between flare and discontinuation of therapy was statistically significant (p<0.001). No significant increase of rate of flare in a subgroup of the same patients during 2020 was observed. CONCLUSION: Treatment discontinuation seems to be an important cause of disease flare. Our findings suggest that abrupt drug withdrawal should be avoided or evaluated with caution on the basis of individual infection risk and comorbidities.