[COVID-19 and Lupus Nephritis Flares in Unvaccinated Patients: A Case Report and Literature Review].

Viral infections are one of the most common triggers of Systemic Lupus Nephritis (SLE) flare-ups. COVID-19 pneumonia can be severe in patients affected by SLE representing a risk factor for lupus nephritis flare. We report the case of a 28-year-old woman with a history of lupus nephritis (LN), who relapsed with severe nephritic-nephritic syndrome after the resolution of COVID-19 pneumonia. In addition, we conducted a literature review to analyze all described cases of LN, vaccinated and unvaccinated, in COVID-19 showing that the course of COVID-19 is more severe in SLE patients with renal involvement, especially in those who have not been vaccinated. Vaccination is the most important measure for preventing COVID-19 in people with rheumatic diseases such as SLE. The case and data we present suggests that LN relapses can occur even after the infection has resolved and illustrates the benefit of vaccination, the role of modulation of immunosuppression during COVID-19 and the specific risk of disease relapse during SARS-CoV-2 infection.