title: Postoperative atypical hemolytic uremic syndrome associated with complement c3 mutation.
abstract: Atypical hemolytic uremic syndrome (aHUS) can be distinguished from typical or Shiga-like toxin-induced HUS. The clinical outcome is unfavorable; up to 50% of affected patients progress to end-stage renal failure and 25% die during the acute phase. Multiple conditions have been associated with aHUS, including infections, drugs, autoimmune conditions, transplantation, pregnancy, and metabolic conditions. aHUS in the nontransplant postsurgical period, however, is rare. An 8-month-old boy underwent surgical repair of tetralogy of Fallot. Neurological disturbances, acute renal failure, thrombocytopenia, and microangiopathic hemolytic anemia developed 25 days later, and aHUS was diagnosed. Further evaluation revealed that his complement factor H (CFH) level was normal and that anti-FH antibodies were not detected in his plasma. Sequencing of his CFH, complement factor I, membrane cofactor protein, complement factor B, and thrombomodulin genes was normal. His ADAMTS-13 (a disintegrin-like and metalloprotease with thrombospondin-1 repeats 13) activity was also normal. However, he had a potentially causative mutation (R425C) in complement component C3. Restriction fragment length polymorphism analysis revealed that his father and aunt also had this mutation; however, they had no symptoms of aHUS. We herein report a case of aHUS that developed after cardiovascular surgery and was caused by a complement C3 mutation.
authors.affiliation: Department of Pediatrics, Gifu Prefectural General Medical Center, 4-6-1 Noishiki, Gifu 500-8717, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Matsukuma
authors.affiliation: Department of Pediatrics, Gifu Prefectural General Medical Center, 4-6-1 Noishiki, Gifu 500-8717, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Imamura
authors.affiliation: Department of Pediatric Cardiovascular Surgery, Gifu Prefectural General Medical Center, 4-6-1 Noishiki, Gifu 500-8717, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Iwata
authors.affiliation: Department of Pediatric Cardiovascular Surgery, Gifu Prefectural General Medical Center, 4-6-1 Noishiki, Gifu 500-8717, Japan.
authors.forename: Takamasa
authors.initials: T
authors.lastname: Takeuchi
authors.affiliation: Department of Blood Transfusion Medicine, Nara Medical University, 840 Shijyou-cho, Kashihara, Nara 634-8521, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yoshida
authors.affiliation: Department of Blood Transfusion Medicine, Nara Medical University, 840 Shijyou-cho, Kashihara, Nara 634-8521, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fujimura
authors.affiliation: Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, 5-7-1 Fujishirodai, Suita, Osaka 565-8565, Japan.
authors.forename: Xinping
authors.initials: X
authors.lastname: Fan
authors.affiliation: Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, 5-7-1 Fujishirodai, Suita, Osaka 565-8565, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Miyata
authors.affiliation: Department of Pediatric Cardiology, Gifu Prefectural General Medical Center, 4-6-1 Noishiki, Gifu 500-8717, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kuwahara