Atypical hemolytic uremic syndrome with a C3 variant following COVID-19: a case report - Ando, Masato; Kubota, Kazuo; Kadowaki, Saori; Kawamoto, Minako; Kawamoto, Norio; Okamoto, Haruka; Nagaya, Soichiro; Miwa, Yuki; Ohnishi, Hidenori (Frontiers in Pediatrics, 2025)