PRTN3 and vasculitis: We performed an electronic search of the MEDLINE, EMBASE, CINAHL, and EMCARE databases for research studies and case series and reports published in the English language between April 2020 and February 2022. Our review suggests that patients with COVID-19 infection who had proteinase 3-ANCA positive vasculitis with diffuse alveolar haemorrhage had fatal outcomes.