Rapidly progressive paucimmune glomerulonephritis following COVID-19 infection

ABSTRACT

Case Report A 78-year-old female presented to our observation for asthenia, low-grade fever and arthralgia from some months. Past medical history at September 2020 SARS-Cov 2 infection with asymptomatic course;at July 2021 second SARS-CoV2 infection complicated by interstitial pneumonia with one intercurrent dose of ChAdOx1 nCoV-19 vaccine. Diagnostic tests revealed acute renal failure, severe anemia subjected to blood transfusions, COVID-19 RT-PCR negativity and p-ANCA positivity. CT thorax showed 5% lung involvement suggestive of outcomes of COVID- 19. Renal needle biopsy diagnosed with rapidly progressive paucimmune glomerulonephritis, therefore she started steroids and first infusion of Rituximab. Discussion: The relationship between SARS-CoV-2 and ANCA-vasculitis could involve high virus affinity for ACE2 receptors, with endothelial cell invasion, activation of the inflammatory cascade, cytokine storm, abnormalities in the coagulation/fibrinolytic system, thrombotic microangiopathy, and endothelial cell damage. ANCA is produced by cytokines, activated neutrophils, and macrophages, with induction of vasculitis by neutrophil extracellular traps, including onset of necrotizing crescentic glomerulonephritis. Furthermore the virus could directly damage renal tissues. In literature ANCA-vasculitis in the setting of COVID-19 has been already reported in 5 patients. Conclusions: COVID-19 may be a trigger of this life-threatening autoimmune disease. More clinical and experimental investigations are necessary to further establish and confirm a causal link between these diseases.