ABSTRACT
Many reports have described a high incidence of acute kidney injury (AKI) among patients with COVID-19. Acute tubular necrosis has been reported to be the most common damage in these patients, probably due to hemodynamic instability. However, other complex processes may be involved, related to the cytokine storm and the activation of innate and adaptive immunity. Here, we describe a patient who developed an antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis with rapidly progressive glomerulonephritis and lung involvement and an antiphospholipid syndrome soon after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. After viral pneumonia was excluded by bronchoalveolar lavage, the patient has been treated with rituximab for amelioration of kidney function and resolution of thrombosis without any adverse event. We conclude that COVID-19 may trigger autoimmune diseases including ANCA-associated vasculitis. Thus, this diagnosis should be taken in consideration in COVID-19 patients, especially when they develop AKI with active urinary sediment. In addition, considering the relationship between these 2 diseases, SARS-CoV-2 infection should be excluded in all patients with a new diagnosis ANCA-associated vasculitis before starting immunosuppressive therapy.